Post installed rebar connections

Transcription

1 Post installed rebar connections Post installed rebar connections Basics of post installed rebar connections Hilti HIT-RE 500 post installed rebar Hilti HIT-HY 150 post installed rebar Hilti HIT- HY 150 MAX post installed rebar 1 /

2 Basics of post installed rebar connections Basics of post installed rebar connections 1 Applications 1.1 Advantages of post-installed rebar connections With the use of the Hilti-HIT injection systems it is possible to connect new reinforcement to existing structures with maximum confidence and flexibility. design flexibility reliable like cast in horizontal, vertical and form work simplification defined load characteristics overhead simple, high confidence application 1.2 Application examples Post installed rebar connections are widely used within the construction industry in a wide range of applications, which vary from new construction projects, to structure upgrades and infrastructure requalifications. Post-installed rebar connections in new construction projects Diaphragm walls Slab connections Misplaced bars Vertical/horizontal connections / 2009

3 Basics of post installed rebar connections Post-installed rebar connections in structure updgrades Wall strenghtening New slab constructions Joint strenghtening Cantilevers/balconies Post-installed rebar connections in infrastructure requalifications Slab widening Structural upgrade Slab strenghtening Side-walk upgrade 1 /

4 Basics of post installed rebar connections 2 Rebar basics 2.1 Definition of rebar Rebar is standing for REinforcement BAR. At Hilti the word is used for a reinforcement bar inserted into a borehole filled with Hilti HIT in reinforced concrete structures, in other words for post-installed reinforcement. Post-installed reinforcement can be split up into four different main applications: Good detailing practice Shear studs Rebar as structural rebar Rebar as an anchor In the course of the Anchor FTM the focus will be on the last two types of applications. Chapter 3, Adhesive Anchoring Systems, deals with rebar as an anchor. The current chapter focuses on rebar as structural rebar, where the reinforcement is purely loaded in the longitudinal direction. l v l 0 l bd 2 / 3 l bd 10 d s Figure 2.1: Example of structural rebar application Structural rebar is characterized by very high loads. The reinforcement is often loaded up to steel yielding. The concrete structure (connection) shows a good serviceability. The deformations are small and due to this the crack width and therefore the influences by the environment (corrosion) are limited. The concrete connections behave as a monolithic structure or in other words as if the concrete was poured in one go. The high loads which can occur in either the anchorage or the splice can lead to an embedment length up to 15 till 80 times the diameter of the reinforcement. The design can be done according to two design concepts; Structural code, for instance EC2 EN :2004 chapter 8.4 anchorage of longitudinal reinforcement, based on approvals (e.g. ETA according to EOTA TR023) See paragraph 4 of this chapter for an overview of the approvals Hilti HIT-Rebar design concept, based on the American Standard (ACI ), where the allowable bond stress is controlled by splitting / spalling behaviour. For this type of connections an engineer is usually involved in the design / 2009

5 Basics of post installed rebar connections 2.2 Rebar as an anchor Rebar as an anchor is characterized by the fact it is not possible to splice the reinforcement (due to e.g. lack of useable reinforcement). The loads are typically smaller as in the case of structural rebar and the serviceability is slightly lower. The anchor failure modes like concrete cone failure or combined concrete cone and pull-out failure are considered in this application according to standard anchor design. For this type of connections an engineer is usually involved in the design. 2.3 Cast-in ribbed bars Generally, for load transfer in reinforced concrete only tensile or compressive forces in bars are considered. For ribbed bars, the load transfer in concrete is governed by the bearing of the ribs against the concrete (figure 2.3.a). The force reaction in the concrete is assumed to form a compressive strut in the direction of 45. For higher bond stress values, the concentrated bearing forces in front of the ribs cause the formation of cone-shaped cracks starting at the crest of the ribs. The resulting concrete keys between the ribs transfer the bearing forces into the surrounding concrete, but the wedging action of the ribs remains limited. In this stage the displacement of the bar with respect to the concrete (slip) consists of bending of the keys and crushing of the concrete in front of the ribs. The bearing forces, which are inclined with respect to the bar axis, can be decomposed into directions parallel and perpendicular to the bar axis. The sum of the parallel components equals the bond force, whereas the radial components induce circumferential tensile stresses in the surrounding concrete, which may result in longitudinal radial (splitting / spalling) cracks. Figure 2.3.a: Load transfer from ribbed bars into concrete Two failure modes can be considered: a) Bond failure (fig. 2.3.a): If the confinement (concrete cover, transverse reinforcement) is sufficient to prevent splitting of the concrete cover, bond failure is caused by pull-out of the bar. In that case the concrete keys are sheared off and a sliding plane around the bar is created. Thus, the force transfer mechanism changes from rib bearing to friction. The shear resistance of the keys can be considered as a criterion for this transition. It is attended by a considerable reduction of the bond stress. Under continued loading the sliding surface is smoothed due to wear and compaction, which will result in a further decrease of the bond stress, similar to the case of plain bars. 1 /

6 Basics of post installed rebar connections b) Splitting failure (fig. 2.3.b): If the radial cracks propagate through the entire cover, bond splitting failure is decisive. In that case the maximum bond stress follows from the maximum concrete confinement, which is reached when the radial cracks have penetrated the cover for about 70%. Further crack propagation results in a decrease of the confining stresses. At reaching the outer surface these stresses are strongly reduced, which results in a sudden drop of the bond stress. Figure 2.3.b 2.4 Lapped bar splices Model for load transfer at lapped bar splices The load transfer between bars is performed by means of compressive struts in the concrete (fig ). A 45 truss model is assumed. The resulting perpendicular forces act in a similar way as the splitting forces. The splitting forces normally are taken up by the transverse reinforcement. Small splitting forces are attributed to the tensile capacity of the concrete. The amount of the transverse or tie reinforcement necessary is specified in the design codes. Figure 2.4.1: Load transfer at lap splices Influence of spacing and cover on splitting and spalling of concrete In most cases the reinforcement bars are placed close to the surface of the concrete member to achieve good crack distribution and economical bending capacity. For splices at wide spacing (normally in slabs, fig a), the bearing capacity of the concrete depends only on the thickness of the concrete cover. At narrow spacing (normally in beams, fig b) the bearing capacity depends on the spacing and on the thickness of the cover. In the design codes the reduction of bearing capacity of the cover is taken into account by means of multiplying factors for the splice length. Figure a Figure b Bond behaviour of post-installed ribbed bars The load transfer for post-installed bars is similar to cast in bars if the stiffness of the overall load transfer mechanism is similar to the cast-in system. The efficiency depends on the strength / 2009

7 Basics of post installed rebar connections of the adhesive mortar against the concentrated load near the ribs and on the capacity of load transfer at the interface of the drilled hole. In many cases the bond values of post-installed bars are higher compared to cast in bars due to better performance of the adhesive mortar. But for small edge distance and/or narrow spacing splitting or spalling forces become decisive due to the low tensile capacity of the concrete. 3 Design basics 3.1 Rebar design methods Post-installed reinforcement connections can basically be designed in compliance with the national codes. Hilti is offering two design methods of which one is based on the Eurocode 2 (EC2 EN :2004) and the other one on the American Standard (ACI ). The most important characteristics will be explained in the following paragraphs. 3.2 Rebar design according to EC2/ETA approach The new technical report EOTA TR 023 (Assessment of post-installed rebar connections) establishes a common method to qualify chemical anchors in compliance with EC2. Chemical anchors must comply with a predefined step-diagram for the different concrete classes (Figure 3.2: Chemical anchors without limitations). In general it shall be shown by the tests as described in the TR 023 that the post-installed rebar systems can develop the same design values of bond resistance with the same safety margin as cast-in place rebars according to EC2. In EC2 no requirements for testing are given, but the values for fbd are published. These values are valid for worst case conditions, minimum concrete cover, minimum spacing and minimum transverse reinforcement. In Figure 3.2 a comparison is given which bond resistance in the tests and evaluation according TR 023 have to be reached (on y- axis) to show equivalence with the values f bd (on x- axis). A European Technical Approvals according to the EOTA TR023 allows a design according to EC2. However a design for fire resistance, fatigue, dynamic or seismic loading are excluded. The ETA for Rebar proves that approved systems are robust and durable. Influences of bad cleaning, wet holes, creep, freeze/thaw, durability, corrosion resistance, installation directions are tested within the approval. The post-installed rebar connections assessed according to TR 023 shall be designed as straight cast-in reinforcement according to EC2 using the values of the design bond resistance fbd for deformed bars. The definition of the bond region in EC2 is valid also for post-installed reinforcement. The conditions in EC2 concerning detailing (e.g. concrete cover in respect to bond and corrosion resistance, bar spacing, transverse reinforcement) shall be complied with. 1 /

8 Basics of post installed rebar connections Figure 3.2: Chemical anchors without limitations from EOTA TR023 The following additional provisions have to be taken into account. To prevent damage of the concrete during drilling the following requirements have to be met: c min = ,06l v 2d s (mm) for hammer drilled holes, with ds being the diameter of the rebar c min = ,08l v 2d s (mm) for compressed air drilled holes The factors 0,06 and 0,08 take into account the possible deviations during the drilling process. This value might be smaller if special drilling aid devices are used. Minimum clear spacing between two post-installed rebars a = 40 mm 4d s To account for potentially different behaviour of post-installed and cast-in rebars in cracked concrete, in general, the minimum embedment length l b,min and l 0,min given in EC2 for anchorages and overlap splices shall be increased by a factor of 1,5. This increase may be neglected if it can be shown that the bond strength of the selected postinstalled rebars and cast-in rebars in cracked concrete (w = 0,3 mm) is similar. In this case the influence of cracks openings (crack movement tests) can be neglected because for rebar connections several rebars are present (redundant fastening) and not all of the rebars will be situated in a longitudinal crack. The transfer of shear forces between new and old concrete shall be designed according to EC2. See also paragraph 3.4 strut-and-tie model. The reader is referred to the paragraph 4 EC2 Design for more detail about this design concept / 2009

9 Basics of post installed rebar connections 3.3 Hilti HIT-Rebar design and ACI approach The American Standard ACI (American Concrete Institute) gives an explicit formula for the design of anchorages and splices that considers splitting and spalling as a function of concrete cover and bar spacing. This function is adapted and extended for post-installed reinforcement for the Hilti HIT-Rebar design concept. The embedment length of an anchorage or splice is defined as a function of concrete strength, the bar diameter, the minimum edge distance or spacing and a coefficient taking into account the transverse reinforcement. In figure 3.3 a typical design bond stress f bd curve as a function of the minimum edge distance/spacing distance, c d is shown for a concrete class C20/25 and for a rebar with a diameter of 12 mm (EC2/ETA approach). In this figure the equivalent design bond stresses resulting from the ACI and the EC2/ETA approaches are plotted to illustrate the two methods (the design bond stresses shown in the figure shall not be used for design purposes). The reduction of anchoring length allowed by ACI and EC2/ETA in specific conditions can be assimilated to an increase of the equivalent design bond stress if c d changes within certain limits. The equivalent design bond stress is defined by an inclined line and it increases with larger values of c d. The increase in the design bond stress is limited by the maximum pull-out bond stress, which is a value which is given by the standards in the case of a cast-in reinforcement. For post-installed reinforcement, the maximum design bond stress is a function of the bonding agent and not necessarily equals that of cast-in bars. Thus, the limitation for bond failure in the code has been replaced by the specific design bond stress of the bonding agent for the specific application conditions and the splitting function has been adapted according to the tests. fbd N/mm N/mm c ACI approach d,min c d C20/25, Ø = 12 mm EC2/ETA approach c d = min(a/2, c, c 1 ) Figure 3.3: equivalent design bond stress f bd as a function of c d., derived from reduction of anchoring lenght according to ACI and EC2/ETA. 1 /

10 Basics of post installed rebar connections Interaction of concrete cover and transverse reinforcement (splitting reinforcement) Tests show that transverse reinforcement improves the splitting capacity. Transverse reinforcement can be taken into account by adding a substitute value for the cover. The ACI code explicitly takes into account the influence of transverse reinforcement able to prevent splitting by means of the transverse reinforcement index K tr. f bd = f ck c + K tr 4 φ ξ ; A tr f yt K tr = ; s n c + K tr φ 2.5 for cast - in bars with: A tr total cross-sectional area of all transverse reinforcement that is within the spacing s and that crosses the potential plane of splitting through the reinforcement being developed [mm 2 ] f yt yield strength of transverse reinforcement [N/mm 2 ] s maximum spacing of transverse reinforcement within b, center to center [mm] n number of bars being developed along the plane of splitting [-] ξ substitute for various adjustment factors Hilti HIT-Rebar design concept c + K for tr 2. 5 (post-installed reinforcement and cast-in reinforcement): φ f bd f ck c + K = 4 γ φ tr for c + K tr > 2. 5 φ (bonded-in bars only): f bd = f ck c + K tr γ φ where: f bd design bond strength φ nominal bar size f ck characteristic concrete cylinder strength c = c d = min(a/2, c, c 1 ) K tr see above γ bar size factor For more detailed Information see: Kunz, J.; Münger, F.: Splitting- and bond failure of post-installed rebar splices and anchoring. ; Bond in Concrete from research to standards, Proceedings of the 3rd International Symposium held at the Budapest University of Technology and Economics, Budapest, Hungary, 20 to 22 November 2002, p (Copy available from Hilti Technical Service) / 2009

11 Basics of post installed rebar connections 3.4 Strut-and-tie model The tensile bearing capacity of concrete is very low compared to its compressive strength. For this reason tensile forces are attributed to the steel reinforcement of the concrete member. The reinforcement should be adequately anchored in the nodes {Clause 6.5.3(2), EC2: EN :2004}. Joint to be roughened Crack limitation Tension cord Figure 3.4: Strut-and-tie-model Compression cord and strut (concrete) Tension ties A strut-and-tie model is used to calculate the load path in reinforced concrete members. Where a non-linear strain distribution exists (e.g. supports) strut-and-tie models may be used {Clause 6.5.1(1), EC2: EN :2004}. Strut-and-tie models consist of struts representing compressive stress fields, of ties representing the reinforcement and of the connecting nodes. The forces in the elements of a strut-and-tie model should be determined by maintaining the equilibrium with the applied loads in ultimate limit state. The ties of a strut-and-tie model should coincide in position and direction with the corresponding reinforcement {Clause 5.6.4, EC2: EN :2004 Analysis with strut and tie models}. 3.5 Joint to be roughened The model of inclined compressive struts is used to transfer the shear forces through the construction joint at the interface between concrete cast at different times. Therefore a rough interface is required to provide sufficient cohesion in the construction joint {Clause 6.2.5(2), EC2: EN :2004}. Rough means a surface with at least 3 mm roughness (R t > 3 mm), achieved by raking, exposing the aggregate or other methods giving an equivalent behaviour. 3.6 Anchorage of reinforcement The reinforcement has to be anchored at places where it is no longer needed. These situations may occur: when the load path of the tensile force has ended (e.g. support, figure 3.6.a) at curtailment of reinforcement (see figure 3.6.b) compression bar anchorage (see figure 3.6.c). 1 /

12 Basics of post installed rebar connections Figure 3.6.a: Support, truss Figure 3.6.b: Tensile force has ended Figure 3.6.c: Compression 3.7 Lapped splice of reinforcement Lapped splices are used to achieve continuity in the tensile tie of the truss model at construction joints. The load from one bar to the other is transferred by means of compressive struts in the concrete. A 45 -truss model is assumed. The resulting splitting force (design bond stress) is limited to a value depending on the surface characteristics of the reinforcement, the tensile strength of the concrete and confinement of surrounding concrete. This depends on sufficient concrete cover, spacing of bar, transverse pressure and by the transverse reinforcement {Clause 6.6, EC2: EN :2004}. Figure 3.7: Lapped splice 4 EC2 design 4.1 General The actual position of the reinforcement in the existing structure shall be determined on the basis of the construction documentation and taken into account when designing. The transfer of shear forces between new concrete and existing structure shall be designed according to EC2 EN :2004. See also paragraph 3.4 Strut-and-tie model The joints for concreting must be roughened to at least such an extent that aggregate protrude. See also paragraph 3.5 Joint to be roughened. The design of post-installed rebar connections and determination of the internal section forces to be transferred in the construction joint shall be verified in accordance with EC2 EN :2004. When ascertaining the tensile force in the rebar, allowance shall be made for the statically effective height of the bonded-in reinforcement. See also paragraph 5.2 Example with overlap joint / 2009

13 Basics of post installed rebar connections 4.2 Determination of the basic anchorage length The calculation of the required anchorage length shall take into consideration the type of steel and bond properties of the reinforcement. The required basic anchorage length l b,rqd shall be determined in accordance with clause 8.4.3, EC2: EN :2004: l b,rqd = (d s / 4) (σ sd / f bd ) with: d s = diameter of the rebar σ sd = calculated design stress of the rebar f bd = design value of bond strength according to corresponding ETA, in consideration of the coefficient related to the quality of bond conditions and, of the coefficient related to the bar diameter and of the drilling technique. Refer to the relevant approval or technical data sheet for details. 4.3 Determination of the design anchorage length The required design anchorage length l bd shall be determined in accordance with clause 8.4.4, EC2: EN :2004: l bd = α 1 α 2 α 3 α 4 α 5 l b,rqd l b,min Where α 1, α 2, α 3, α 4 and α 5 are coefficients given in Table 4.1. α 1 is for the effect of the form of the bars assuming adequate cover (post-installed reinforcement is always straight) α 2 is for the effect of concrete minimum cover α2 = 1 0,15 ( c d d0 )/d0 straight bars; min ( a/2;c ;c) c d = 1 With no edge distance, α 2 = 0,7 if the spacing given in the table below are fulfilled: d s (mm) Spacing (mm) a (mm) α 3 is for the effect of confinement by transverse reinforcement α 4 is for the influence of one or more welded transverse bars along the design anchorage length l bd. (no welded transverse reinforcement possible with postinstalled reinforcement) α 5 is for the effect of the pressure transverse to the plane of splitting along the design anchorage length. The product (α 2 α 3 α 5 ) 0,7 1 /

14 Basics of post installed rebar connections l b,rqd = according to section 5.2 l b,min = minimum anchorage length according to clause 8.4.4, EC2: EN :2004 = max {0.3 l b,rqd ; 10d s ; 100 mm} under tension = max {0.6 l b,rqd ; 10d s ; 100 mm} under compression (Please note that the minimum anchorage length may be increased by factor 1,5 according to EOTA TR023, 4.2. Refer to the relevant approval or technical data sheet for details.) Table 4.1: Values of α 1, α 2, α 3, α 4 and α 5 coefficients Influencing factor Type of anchorage Reinforcement bar In tension In compression Shape of bars Straight α 1 = 1.0 α 1 = 1.0 Concrete cover Straight α 2 = (c d α 2 = 1.0 ø)/ø Confinement by Straight α 3 = 1 Kλ α 3 = 1.0 transverse reinforcement Confinement by welded transverse Straight α 4 = 1.0 α 4 = 1.0 reinforcement Confinement by transverse pressure where: λ Straight α 5 = p = (ΣA st - ΣA st,min )/ A s ΣA st cross-sectional area of the transverse reinforcement along the design anchorage length lbd ΣA st,min cross-sectional area of the minimum transverse reinforcement = 0.25 As for beams and 0 for slabs As area of a single anchored bar with maximum bar diameter K values shown in Figure 4.10 p transverse pressure [MPa] at ultimate limit state along lbd - Figure 4.3 : Values of K for beams and slabs 4.4 Overlap joints Forces are transmitted from one bar to another by lapping the bars. The detailing of laps between bars shall be such that: - the transmission of the forces from one bar to the next is assured - spalling of the concrete in the neighbourhood of the joints does not occur - large cracks which affect the performance of the structure do not occur / 2009

15 Basics of post installed rebar connections Laps between bars should not be located in areas of high moments / forces (e.g. plastic hinges) and at any section normally be arranged symmetrically. The arrangement of lapped bars should comply with Figure 4.4. The clear distance between lapped bars should be 4ø and 50 mm, otherwise the lap length should be increased by a length equal to the clear space where it exceeds 4ø or 50 mm. 3ø Figure 4.4: Adjacent laps The required design lap length l 0 shall be determined in accordance with clause 8.7.3, EC2: EN :2004: l 0 = α 1 α 2 α 3 α 5 α 6 l b,rqd l 0,min with: l b,rqd = according to section 4.2 l 0,min = minimum lap length = max {0.3α 6 l b,rqd ; 15d s ; 200 mm} (Please note that the minimum anchorage length may be increased by factor 1,5 according to EOTA TR023, 4.2. Refer to the relevant approval or technical data sheet for details.) Values of α 1, α 2, α 3 and α 5 may be taken from Table 4.1; however, for the calculation of α 3, ΣA st,min should be taken as 1,0 A s (σ sd /f yd ), with A s = area of one lapped bar. α 6 = (ρ 1 /25)0.5 but neither not exceeding 1,5 nor less than 1,0, where ρ 1 is the percentage of reinforcement lapped within 0.65l 0 from the centre of the lap length considered. Values of α 6 are given in Table 4.2. (Note: For postinstalled rebar applications α 6 = 1,5 for the majority of the cases) Table 4.2: Values of the coefficient α 6 Percentage of lapped bars < 25% 33% 50% > 50% relative to the total crosssection area α 6 1 1,15 1,4 1,5 4.5 Embedment depth for overlap joints Overlap joint for rebars: For calculation of the effective embedment depth of overlap joints the concrete cover at end-face of the postinstalled rebar c1 shall be considered: l v l 0 + c 1 with: l 0 = required lap length according to paragraph 4.4. c 1 = concrete cover at end-face of bonded-in rebar. See Figure /

16 Basics of post installed rebar connections Figure 4.5: Concrete cover c 1 If the clear distance between the overlapping bars is greater than 4d s the lap length shall be enlarged by the difference between the actual clear distance and 4d s. 4.6 Concrete cover The minimum concrete cover required for bonded-in rebars is shown in the ETA approvals in relation to the drilling method and the hole tolerance. Furthermore the minimum concrete cover given in clause , EC2: EN : 2004 shall be observed. 4.7 Transverse reinforcement The requirements of transverse reinforcement in the area of the post-installed rebar connection shall comply with clause 8.7.4, EC2: EN : Connection joint In case of a carbonated surface of the existing concrete structure the carbonated layer shall be removed in the area of the post installed rebar connection with a diameter of d s + 60 mm prior to the installation of the new rebar. The depth of concrete to be removed shall correspond to at least the minimum concrete cover for the respective environmental conditions in accordance with EC2: EN : / 2009

17 Basics of post installed rebar connections 5 Design examples 5.1 Anchorage: End support of slab, simply supported h = 300 d = 260 a 1 = 130 a l = 260 l n = 6,50 m h = 300 slab: l n = 6,50 m, Q k = 5 kn/m 2,h = 300 mm,d = 260 mm wall: h = 300 mm Concrete strength class: C20/25, dry concrete Properties of reinforcement: f yk = 500 N/mm2 Short-term/long-term temperature is 20 C Fire resistance: F90 (90 minutes) Loads: G d = 1,35 x 7,5 = 10,1 kn/m²; Q d = 1,5 x 5,0 = 7,5 kn/m² = 17,6 kn/m² Structural analysis (design forces) based on l eff : M Sd = 17,6 x 6,762 / 8 = 100,5 knm/m V Sd = 17,6 x (6,76 / 2) = 59,5 kn/m Bottom reinforcement required at mid span: A s,req = 100,5 x 1,15 / (0,26 x 0,9 x 0,5) = 988 mm²/m reinforcement provided: 16, s = 200 mm; A s,prov = 1010 mm²/m Bottom reinforcement at support: A s,min = 0,4 x 1 x 2,2 x 150 x 1000 / 500 = 264 mm²/m {Clause 7.3.2(2), EC2: EN :2004} A s,min = 0,50 x 988 = 494 mm 2 /m {Clause (1), EC2: EN :2004} {Clause (4), EC 2: EN :2004} A s,min = 0,25 x 988 = 247 mm²/m {Clause (1), EC2: EN :2004} A s,req = 59,5 x 1 / 0,9 x 1,15 / 0,5 = 152 mm 2 /m (al =d) {Clause (2), EC2: EN :2004} Decisive is 494 mm²/m reinforcement provided: 12, s = 200 mm; A s,prov = 565 mm²/m a) Anchorage according to European Technical Approval (ETA) 08/0105, Post-installed rebar connections with Hilti injection mortar HIT-RE 500 Determination of the basic anchorage length The required basic anchorage length l b,rqd shall be determined in accordance with EC2: EN :2004, section 8.4.3: l b,rqd = (d s / 4) x (σ sd / f bd ) with: d s = diameter of the rebar = 12 mm σ sd = calculated design stress of the rebar = (494 / 565) x (500 / 1,15) = 380 N/mm² f bd = design value of bond strength according to corresponding ETA = 2,3 N/mm² l b,rqd = (12 / 4) x (380 / 2,3) = 496 mm 1 /

18 Basics of post installed rebar connections Determination of the design anchorage length The required design anchorage length l bd shall be determined in accordance with EC2: EN :2004, section 8.4.4: l bd = α 1 α 2 α 3 α 4 α 5 l b,rqd l b,min with: l b,rqd as above α 1 = 1,0 for straight bars α 2 = 1 0,15(c d ø)/ø α 2 is for the effect of concrete minimum cover 0,7 1,0 a = = 188 mm a/2 = 94 mm with c1 and c > 94 mm ø = 12 mm α 2 = 0,7 Straight bars, c d = min (a/2, c 1, c) α 3 = 1,0 because of no transverse reinforcement α 4 = 1,0 because of no welded transverse reinforcement α 5 = 1,0 influence of transverse pressure is neglected in this example l bd = 0,7 x 496 = 347 mm 2/3l bd = 231 mm 230 mm l b,min = minimum anchorage length {Clause 8.4.4(1), EC2: EN :2004} = max {0,3 x 496; 10 x 12; 100} = 149 mm b) Anchorage according to Hilti HIT-Rebar design method (splitting): Reinforcement provided: 12, s = 200 mm; A s,prov = 565 mm²/m Mortar: Hilti HIT-RE 500 F Sd = 494 x 0,5 / 1,15 = 214,8 kn/m Steel: F Rd = 5 x (f yk x π x 2 x ¼) / у s = 245,9 kn/m > 214,8 kn/m ok Concrete (splitting) / Mortar (pull-out): Due to large edge distances in all directions (confined concrete) the failure mode splitting of concrete is not becoming decisive, but the pull out failure mode: f bd = 6.9 N/mm 2 F Rd = n(l bd x x π x f bd ) = 5(l bd x 12 x π x 6.9) = kn/m l bd = 165 mm l b,min = 120 mm (10 x ) ok Fire resistance: Fire rating class F 90 (90 min.) (design table see paragraph 4.7): F st,req = 0,6 x 66,1 = 39,7 kn/m = 7,9 kn/bar {Clause (4) and (5), EC2: ENV :1995} Hilti HIT-RE 500: 12 l inst = 14,5 cm; F s,t = 6,02 kn l inst = 18 cm; F s,t = 15,0 kn / 2009

19 Basics of post installed rebar connections Intermediate values may be interpolated linearly: l inst = 16,5 cm; F s,t = 11,2 kn/bar > 7,9 kn/bar l inst = 165 mm Top reinforcement 300 d = 260 a 1 = 130 a l = 260 l n = 6.50 m h = 300 Top reinforcement at support: Minimum reinforcement: 25% of bottom steel required at mid-span {Clause (2), EC2: EN :2004} A s,req = 0,25 x 988 = 247 mm 2 /m A s,min = 0,4 x 1 x 2,2 x 150 x 1000 / 500 = 264 mm 2 /m {Clause 7.3.2(2), EC2: EN :2004} Decisive is 264 mm²/m reinforcement provided: 12, s = 300 mm; A s,prov = 377 mm²/m a) Anchorage according to European Technical Approval (ETA) 08/0105, Post-installed rebar connections with Hilti injection mortar HIT-RE 500 Determination of the basic anchorage length The required basic anchorage length l b,rqd shall be determined in accordance with EC2: EN :2004, section 8.4.3: l b,rqd = (d s / 4) x (σ sd / f bd) with: d s = diameter of the rebar = 12 mm σ sd = calculated design stress of the rebar = (264 / 377) x (500 / 1.15) = 304 N/mm² f bd = design value of bond strength according to corresponding ETA = 2,3 N/mm² l b,rqd = (12 / 4) x (304 / 2,3) = 397 mm Determination of the design anchorage length The required design anchorage length l bd shall be determined in accordance with EC2: EN :2004, section 8.4.4: l bd = α 1 α 2 α 3 α 4 α 5 l b,rqd l b,min with: l b,rqd as above α 1 = 1,0 for straight bars α 2 = 1 0,15(c d ø)/ø α 2 is for the effect of concrete minimum cover 0,7 1,0 a = = 288 mm a/2 = 144 mm with c1 and c > 144 mm ø = 12 mm 0,7 α 3 = 1,0 because of no transverse reinforcement α 4 = 1,0 because of no welded transverse reinforcement α 5 = 1,0 influence of transverse pressure is neglected in this example l bd = 0,7 x 397 = 278 mm 280 mm Can be critical with drilling! l b,min = minimum anchorage length {Clause 8.4.4(1), EC2: EN :2004} = max {0.3 x 397; 10 x 12; 100} = 120 mm ok 1 /

20 Basics of post installed rebar connections b) Anchorage according to Hilti HIT-Rebar design method (shear): Reinforcement provided: 12, s = 300 mm; A s,prov = 377 mm 2 /m Mortar: Hilti HIT-RE 500 F Sd = 264 x 0,5 / 1,15 = 114,8 kn/m Steel: F Rd = 3,33(f yk x π x 2 x ¼) / уs = 163,7 kn/m > 114,8 kn/m ok Mortar (pull-out): f bd = 6,9 N/mm 2 F Rd = n(l bd x x π x f bd ) = 3,33(l bd x 12 x π x 6,9) = 114,8 kn/m (if h ef < 18 ) l bd = 132 mm l b,min = 120 mm (10 x ) ok Concrete (shear): Uncracked concrete = rebar-cc method situation 1 s 18 ; c 9 ƒ AN = 1,0 (s = 300 mm > 216 mm; c > 108 mm) F Rd = F 0Rd x ƒ AN = 114,8 x 1.0 = 114,8 kn/m (with l bd = 132 mm) l bd = 135 mm 5.2 Example with overlap joint 30 l v l 0 c s = 50 d = h = 300 Bending moment: M Sd = 120 knm/m slab: h = 300 mm; d = 250 mm, cs = 50 mm Concrete strength class: C25/30, Properties of reinforcement: f yk = 500 N/mm² Fire resistance: F60 (60 minutes), Light weight plaster for fire protection: 30 mm 10 top reinforcement: 16, s = 150 mm; A s,prov = 1340 mm²/m cover to face c 1 = 30 mm bottom reinforcement: 10, s = 200 mm; A s,prov = 393 mm²/m Note: reduced load in cast-in bar due to lever arm: η = 250 / 270 = 0,93 a) Overlap joints according to European Technical Approval (ETA) 08/0105, Post-installed rebar connections with Hilti injection mortar HIT-RE 500 Post-installed reinforcement The required design lap length l 0 shall be determined in accordance with EC2: EN :2004, section 8.7.3: l 0 = α 1 α 2 α 3 α 5 α 6 l b,rqd l 0,min with: l b,rqd the basic anchorage length, l b,rqd = (d s / 4) x (σ sd / f bd ) d s = diameter of the rebar = 16 mm σ sd = calculated design stress of the rebar d = 250 mm, z 0,9 x 250 = 225 mm A s,req = 120 x 1,15 / (0,225 x 0,5) = 1227 mm 2 /m σ sd = (1227 / 1340) x (500 / 1,15) = 398 N/mm 2 f bd = design value of bond strength according to corresponding ETA = 2,7 N/mm / 2009

21 Basics of post installed rebar connections l b,rqd = (16 / 4) x (398 / 2.7) = 590 mm α 1 = 1,0 for straight bars α 2 = 1 0,15(c d ø)/ø α 2 is for the effect of concrete minimum cover 0,7 1,0 c = 50-8 = 42 mm c d = 42 mm ø = 16 mm 0,76 α 3 = 1,0 because of no transverse reinforcement α 5 = 1,0 influence of transverse pressure is neglected in this example α 6 = 1,5 influence of percentage of lapped bars relative to the total cross-section area {Clause 8.7.3(1), EC2: EN :2004} l 0 = 0,76 x 1,5 x 590 = 673 mm 675 mm l 0,min = minimum lap length {Clause 8.7.3(1), EC2: EN :2004} = max{0.3 x 1.5 x 590; 15 x 16; 200} = 266 mm ok Cast-in reinforcement l 0 = α 1 α 2 α 3 α 5 α 6 l b,rqd l 0,min with: l b,rqd the basic anchorage length, l b,rqd = (d s / 4) x (σ sd / f bd ) d s = diameter of the rebar = 16 mm σ sd = calculated design stress of the rebar d = 270 mm, z 0,9 x 270 = 243 mm A s,req = 120 x 1,15 / (0,243 x 0,5) = 1136 mm 2 /m σ sd = (1136 / 1340) x (500 / 1,15) = 369 N/mm 2 f bd = design value of bond strength according to corresponding ETA = 2,7 N/mm 2 l b,rqd = (16 / 4) x (369 / 2.7) = 547 mm α 2 = 1 0,15(c d ø)/ø α 2 is for the effect of concrete minimum cover 0,7 1,0 c = 30-8 = 22 mm c d = 22 mm ø = 16 mm 0,94 l 0 = 0,94 x 1,5 x 547 = 771 mm 770 mm Cast-in reinforcement is decisive! l 0,min = minimum lap length {Clause 8.7.3(1), EC2: EN :2004} = max{0,3 x 1,5 x 547; 15 x 16; 200} = 246 mm ok Embedment depth for overlap joints for rebars: l v l 0 + c 1 with: l 0 = required lap length = 770 mm (see above) c 1 = concrete cover at end face of cast-in rebar = 30 mm l v = 800 mm If the clear distance between the overlapping rebars is greater than 4d s (4 x 16 = 64 mm) the lap length shall be enlarged by the difference between the clear distance and 4d s. Most unfavorable case post-installed rebar is located right in the middle between the cast-in rebars. The clear distance between the overlap is: s 22 = (75 8)2 + (20 8)2 = 4633 s 2 = 68 mm = 4 mm 5 mm l v = = 805 mm 1 /

22 Basics of post installed rebar connections b) Overlap joints according to Hilti HIT-Rebar design method (splitting): Post-installed reinforcement Reinforcement provided: 16, s = 150 mm; A s,prov = 1340 mm²/m Mortar: Hilti HIT-RE 500 F Sd = 1340 x 398 = 533,3 kn/m (see above) Steel: F Rd = 6,66(f yk x π x 2 x ¼) / уs = 582,2 kn/m > 533,3 kn/m ok Mortar (pull-out): f bd = 7,1 N/mm 2 ' tr f Concrete (splitting): c (c + Ktr) / = 3.1 > 2.5 f bd is calculated φ f bd = according with: c = min{c, s/2} = 50 mm 4γ Ktr = 0 = 16 mm ' f c = compressive strength of concrete = 25 N/mm2 for C25/30 γ = reinforcement size factor = 0.8 for 18 f bd = 4,6 N/mm 2 Due to edge distances (c = 50 mm) and spacing (s = 150 mm) the failure mode splitting of concrete is decisive. α 6 = 1,5 f bd = 3,1 N/mm 2 {Clause 8.7.3(1), EC2: EN :2004} F Rd = n(l 0 x x π x f bd ) = 6.66( 0 x 16 x π x 3,1) = 533,3 kn/m l 0 = 514 mm Cast-in reinforcement (as above) l 0 = 770 mm Cast-in reinforcement is decisive! Embedment depth for overlap joints for rebars: l v = 805 mm Fire resistance: Fire rating class F 60 (60 minutes) (design table see paragraph 4.7): Clear concrete cover including light weight plaster: c = = 7 cm F st,req = 0.6 x 120 / 0,225 = 320 kn/m = 48 kn/bar {Clause (4) und (5), EC2: ENV :1995} τ T,req = / (16 x π x 770) = 1,2 N/mm 2 Hilti HIT-RE 500: τ T = 1,0 N/mm2 < 1,2 N/mm 2 increase plaster to 4 cm c = 8 cm, τ T = 1,4 N/mm 2 ok c + K / 2009

23 Basics of post installed rebar connections 6 Corrosion behavior The Swiss Association for Protection against Corrosion (SGK) was given the assignment of evaluating the corrosion behavior of fastenings post-installed in concrete using the Hilti HIT-HY 150, Hilti HIT-HY 150 MAX and Hilti HIT-RE 500 injection systems. Corrosion tests were carried out. The behavior of the two systems had to be evaluated in relation to their use in field practice and compared with the behavior of cast-in reinforcement. The SGK can look back on extensive experience in this field, especially on expertise in the field of repair and maintenance work. The result can be summarized as follows: Hilti HIT-HY Hilti HIT-HY 150 MAX The Hilti HIT-HY 150 and Hilti HIT-HY 150 MAX systems in combination with reinforcing bars can be considered resistant to corrosion when they are used in sound, alkaline concrete. The alkalinity of the adhesive mortar safeguards the initial passivation of the steel. Owing to the porosity of the adhesive mortar, an exchange takes place with the alkaline pore solution of the concrete. If rebars are bonded-in into chloride-free concrete using this system, in the event of later chloride exposure, the rates of corrosion are about half those of rebars that are cast-in. In concrete containing chlorides, the corrosion behavior of the system corresponds to that of cast-in rebars. Consequently, the use of unprotected steel in concrete exposed to chlorides in the past or possibly in the future is not recommended because corrosion must be expected after only short exposure times. Hilti HIT-RE 500 If the Hilti HIT-RE 500 system is used in corrosive surroundings, a sufficiently thick coat of adhesive significantly increases the time before corrosion starts to attack the bonded-in steel. The HIT-RE 500 system may be described as resistant to corrosion, even in concrete that is carbonated and contains chlorides, if a coat thickness of at least 1 mm can be ensured. In this case, the unprotected steel in the concrete joint and in the new concrete is critical. If the coat thickness is not ensured, the HIT-RE 500 system may be used only in sound concrete. A rebar may then also be in contact with the wall of the drilled hole. At these points, the steel behaves as though it has a thin coating of epoxy resin. In none of the cases investigated did previously rusted steel (without chlorides) show signs of an attack by corrosion, even in concrete containing chlorides. Neither during this study an acceleration of corrosion was found at defective points in the adhesive nor was there any reference to this in literature. Even if a macro-element forms, the high resistance to it spreading inhibits a locally increased rate of corrosion. Information in reference data corresponds with the results of this study. 7 Fire design If passive fire prevention requirements have to be met, the suitability of rebar connections should be verified additionally to ULS cold design. Large-area building components (walls and floors) can be verified according to tables 1 and 2. The design tables are derived from tests at the University / IBMB Braunschweig following the Standard ISO 834 temperature/time curve. Design for fire resistance is carried out in line with several specific standards. On the following pages only the fire data for Standard according EC2 are given. Details to all available Standards and specific reports are named below the following tables. Note for the following tables 1 to 6: F s,t = force in bar when exposed to fire. Intermediate values may be interpolated linearly. Extrapolating is not permitted. 1 /

24 Basics of post installed rebar connections Hilti HIT-HY 150 rebar Bar perpendicular to slab or wall surface exposed to fire Temperature time curve (acc. ISO 834) l inst Table 1: Maximum force in rebar in conjuction with HIT-HY 150 as a function of embedment depth for the fire resistance classes F30 to F180 (yield strength f yk = 500 N/mm²) according EC2 a) Bar Drill hole F30 F60 F90 F120 F180 [mm] [mm] l inst [mm] F S,T [kn] l inst [mm] F S,T [kn] l inst [mm] F S,T [kn] l inst [mm] F S,T [kn] l inst [mm] F S,T [kn] , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , / 2009

25 Basics of post installed rebar connections Bar Drill hole F30 F60 F90 F120 F180 [mm] [mm] l inst [mm] F S,T [kn] l inst [mm] F S,T [kn] l inst [mm] F S,T [kn] l inst [mm] F S,T [kn] l inst [mm] F S,T [kn] , , , , , , , , , , , , , ,2 Remark: The minimum setting depth is related to l > 15 x d s a) For tables according British- and Singapore Standard (resistance class up to F240) see Warringtonfire report WF or/and IBMB Braunschweig report No 3162/6989 (including supplements). Hilti HIT-HY 150 rebar Bar connection parallel to slab or wall surface exposed to fire Max. bond stress, τ T, depending on actual clear concrete cover for classifying the fire resistance. It must be verified that the actual force in the bar during a fire, F s,t, can be taken up by the bar connection of the selected length, l inst. Note: Cold design for ULS is mandatory. F s, T (l inst c f ) π τ T where: (l inst c f ) l s ; l s = lap length = nominal diameter of bar l inst c f = selected overlap joint length; this must be at least l s, but may not be assumed to be more than 80 τ T = bond stress when exposed to fire Temperature time curve (acc. ISO 834) l inst c f c Table 2: Critical temperature-dependent bond stress, τ crit,t, concerning overlap joint for Hilti-HIT-HY 150 injection adhesive in relation to fire resistance class and required minimum concrete coverage c. Clear concrete cover c Max. bond stress, τ T [N/mm²] [mm] F30 F60 F90 F120 F , ,4 0, ,9 0, ,4 1,2 0,4 60 2,8 1,7 0,7 0,3 70 4,9 2,2 1,2 0,7 1 /

26 Basics of post installed rebar connections Clear concrete cover c Max. bond stress, τ T [N/mm²] [mm] F30 F60 F90 F120 F ,5 1,7 1,0 0,2 90 2,8 2,0 1,5 0, ,0 2,3 1,9 0, ,5 2,7 2,3 1, ,5 2,9 2,6 1, ,0 2,8 1, ,5 3,0 2, ,5 2, ,0 6,5 2, , ,7 7, ,8 7, ,9 7, , , , ,0 Hilti HIT-HY 150 MAX rebar Bar perpendicular to slab or wall surface exposed to fire Temperature time curve (acc. ISO 834) l inst Table 3: Maximum force in rebar in conjuction with HIT-HY 150 MAX as a function of embedment depth for the fire resistance classes F30 to F180 (yield strength f yk = 500 N/mm²) according EC2 a). Bar Drill hole Max. F s,t l inst F30 F60 F90 F120 F180 [mm] [mm] [kn] [mm] [kn] [kn] [kn] [kn] [kn] 80 2,18 0,73 0,24 0, ,21 2,90 1,44 0,82 0, ,2 9,95 5,99 3,69 1, , ,2 13,01 9,52 3, ,2 13,04 5, ,2 9, , ,87 1,95 0,84 0, ,86 8,06 4,45 2,82 0, ,3 16,83 11,86 7,65 2, , ,3 20,66 16,29 7, ,3 22,89 13, ,3 18, , / 2009

27 Basics of post installed rebar connections Bar Drill hole Max. F s,t l inst F30 F60 F90 F120 F180 [mm] [mm] [kn] [mm] [kn] [kn] [kn] [kn] [kn] ,32 4,35 2,16 1,23 0, ,15 17,56 11,59 7,14 2, ,4 28,12 22,15 16,91 6, , ,4 32,7 27,47 16, ,4 32,75 21, ,4 27, , ,53 8,77 4,74 2,95 0, ,08 29,72 22,76 16,66 6, ,6 38,96 32,0 25,89 13, , ,6 44,31 38,21 25, ,6 44,36 31, ,6 40, , ,5 16,38 9,26 5,77 2, ,65 44,53 36,57 29,59 15, ,8 51,56 43,61 36,63 22, , ,8 57,68 50,70 36, ,8 61,26 46, ,8 57, , ,72 38,06 28,12 19,39 7, ,71 60,06 50,11 41,39 23, ,2 86,45 76,5 67,78 49, , ,2 94,09 85,37 67, ,2 94,16 75, ,2 84, , ,13 75,07 62,46 51,73 28, ,63 91,56 79,13 68,23 45, ,1 141,04 128,61 117,71 94, , ,1 150,60 139,70 116, ,1 150,69 127, ,1 138, ,1 a) For HIT-HY 150 MAX rebar only the standard acc. EC2 is available (Data also in Warringtonfire report WF or/and IBMB Braunschweig report No 3884/8246-CM. Hilti HIT-HY 150 MAX rebar Bar connection parallel to slab or wall surface exposed to fire Max. bond stress, τ T, depending on actual clear concrete cover for classifying the fire resistance. It must be verified that the actual force in the bar during a fire, F s,t, can be taken up by the bar connection of the selected length, l inst. Note: Cold design for ULS is mandatory. F s, T (l inst c f ) π τ T where: (l inst c f ) l s ; l s = lap length = nominal diameter of bar l inst c f = selected overlap joint length; this must be at least l s, but may not be assumed to be more than 80 = bond stress when exposed to fire τ T 1 /

28 Basics of post installed rebar connections Table 4: Critical temperature-dependent bond stress, τ crit,t, concerning overlap joint for Hilti-HIT-HY 150 MAX injection adhesive in relation to fire resistance class and required minimum concrete coverage c. Clear concrete cover c Max. bond stress, τ T [N/mm²] [mm] F30 F60 F90 F120 F , , , ,84 0, ,04 0, ,22 0, ,47 0, ,85 0,73 0, ,87 0, ,02 0, ,21 0,59 0, ,35 0,67 0, ,52 0,78 0, ,74 0,91 0, ,02 1,07 0, ,21 0,77 0, ,39 0,91 0, ,61 1,05 0, ,89 1,21 0, ,12 1,37 0, ,20 1,57 0, ,82 0, ,13 0, ,89 2, , , ,20 1, ,22 2, , , , , ,20 Hilti HIT-RE 500 rebar Bar perpendicular to slab or wall surface exposed to fire Temperature time curve (acc. ISO 834) l inst / 2009

29 Basics of post installed rebar connections Table 5: Maximum force in rebar in conjuction with HIT-RE 500 as a function of embedment depth for the fire resistance classes F30 to F240 (yield strength f yk = 500 N/mm²) according EC2 a). Bar Drill hole Max. F s,t l inst Fire resistance of bar in [kn] [mm] [mm] [kn] [mm] F30 F60 F90 F120 F180 F ,38 0,57 0,19 0, ,35 1,02 0,47 0, ,87 1,68 0,88 0,55 0, ,3 3,07 1,71 1,14 0,44 0, , ,19 8,15 4,59 3,14 1,41 0, ,19 9,99 6,75 2,94 1, ,19 12,38 5,08 2, ,19 6,95 3, ,19 8, , ,94 1,27 0,59 0, ,68 2,45 1,31 0,85 0, ,66 4,44 2,48 1,68 0,68 0, ,57 7,76 4,38 2,99 1,33 0, , ,29 15,06 8,5 5,79 2,58 1, ,29 17,63 12,18 5,12 2, ,29 20,66 8,69 4, ,29 11,8 6, ,29 13, , ,8 2,52 1,32 0,83 0, ,79 5,33 2,97 2,01 0,82 0, ,16 10,68 6,02 4,12 1,84 1, ,42 24,29 14,99 10,12 4,41 2, , ,42 27,38 20,65 8,47 4, ,42 312,01 14,16 7, ,42 19,13 9, ,42 21, , ,92 4,65 2,55 1,7 0,61 0, ,60 10,87 6,13 4,19 1,86 1, ,12 23,50 13,55 9,2 4,07 2, ,6 24,69 17,05 7,17 4, ,20 31,34 13,48 7, ,44 22,32 11, ,49 15, , ,59 9,42 5,30 3,61 1,56 0, ,17 21,33 11,95 8,15 3,65 2, ,76 37,92 24,45 17,25 7,35 4, ,75 48,98 36,51 27,53 11,29 6, , ,75 53,10 44,12 20,88 11, ,75 57,94 33,7 17, ,75 42,0 22, ,75 44, ,75 1 /

30 Basics of post installed rebar connections Bar Drill hole Max. F s,t l inst Fire resistance of bar in [kn] [mm] [mm] [kn] [mm] F30 F60 F90 F120 F180 F ,97 26,67 14,93 10,18 4,56 2, ,61 54,31 38,73 27,5 11,42 6, ,18 81,96 66,37 55,15 26,10 13, , ,18 87,11 75,88 45,58 23, ,18 93,16 62,86 35, ,18 73,23 45, ,18 76, , ,77 67,89 48,41 34,37 14,27 8, ,96 111,09 91,60 77,51 39,86 20, ,09 132,69 113,2 99,17 61,30 31, , ,09 139,12 125,09 87,22 52, ,09 146,69 108,82 74, ,09 121,77 87, ,09 126, , ,40 147,72 122,78 104,82 56,35 28, ,52 169,84 144,90 126,94 78,46 40, ,02 225,13 200,19 182,23 133,75 89, , ,02 238,89 220,93 172,46 128, ,02 243,05 194,58 150, ,02 211,16 167, ,02 216, , ,87 209,73 181,67 161,46 106,93 59, ,41 253,27 225,21 205,01 150,47 100, ,82 290,59 262,54 242,33 187,80 138, , ,82 299,86 279,65 225,12 175, ,82 310,75 256,22 206, ,82 274,88 225, ,82 281, , ,10 274,50 243,33 220,87 160,28 105, ,48 322,88 291,71 269,25 208,66 153, ,71 364,35 333,18 310,72 250,13 195, , ,71 374,64 352,19 291,60 236, ,71 386,75 326,16 271, ,71 346,89 291, ,71 354, ,71 a) For tables according the standards to DIN , NF-ENV (EC2), Österreichische Norm B , British-, Singapore- and Australian Standards see Warringtonfire report WF or/and IBMB Braunschweig report No 3357/ Hilti HIT-RE 500 rebar Bar connection parallel to slab or wall surface exposed to fire Max. bond stress, τ T, depending on actual clear concrete cover for classifying the fire resistance. It must be verified that the actual force in the bar during a fire, F s,t, can be taken up by the bar connection of the selected length, l inst. Note: Cold design for ULS is mandatory. F s, T (l inst c f ) π τ T where: (l inst c f ) l s ; / 2009

31 Basics of post installed rebar connections l s = lap length = nominal diameter of bar l inst c f = selected overlap joint length; this must be at least l s, but may not be assumed to be more than 80 τ T = bond stress when exposed to fire Table 6: Critical temperature-dependent bond stress, τ crit,t, concerning overlap joint for Hilti-HIT RE 500 injection adhesive in relation to fire resistance class and required minimum concrete coverage c. Clear concrete cover c Max. bond stress, τ T [N/mm²] [mm] F30 F60 F90 F120 F180 F , , ,897 0, ,209 0, ,630 0,806 0, ,197 1,043 0,655 0, ,962 1,351 0,835 0, ,992 1,748 1,065 0,775 0, ,382 2,263 1,358 0,977 0, ,255 2,930 1,733 1,233 0,669 0, ,780 3,792 2,210 1,556 0,810 0, ,909 2,818 1,963 0,980 0, ,355 3,594 2,477 1,185 0, ,226 4,584 3,125 1,434 0, ,846 3,943 1,735 1, ,456 4,974 2,099 1, ,510 6,276 2,540 1, ,918 3,037 1, ,990 3,718 1, ,498 2, ,00 5,442 2, ,584 3, ,00 7,966 3, ,00 9,639 4, ,00 5, , ,214 11, , , ,00 1 /

32 Basics of post installed rebar connections 8 Fatigue of bonded-in reinforcement for joints with predominantly cyclical imposed loading 8.1 General notes For loadbearing elements which are subjected to considerable cyclic stress the bonded-in connections should be designed for fatigue. In that case evidence for fatigue of reinforcing steel bars, concrete and bond should be provided separately. For simple cases it is reasonable to use simplified methods on the safe side. The partial safety factors for loads are specified in the code for reinforced concrete. The partial safety factors for material are specified in Table 4.3. Table 4.3: Partial safety factors for materials subjected to cyclic loading Evidence for concrete bond reinforcing bars (steel) Partial safety factor Fatigue of reinforcing bars (steel) The resistance for fatigue of reinforcing bars (steel) is specified in the actual code for reinforced concrete. The behaviour of the steel of reinforcing bars bonded-in by means of Hilti HIT is at least as good as cast-in place reinforcement. 8.3 Fatigue of bond and concrete (simplified approach) As a simple and conservative approach on the safe side evidence for fatigue is proven if the following equation is valid: F Sd,fat N Rd f fat where: F Sd,fat N Rd Design value of the anchorage force for the ruling loading model for fatigue. Design resistance for static load of the anchorage (bond and concrete). f fat Reduction factor for fatigue for bond and concrete: f fat = 0.5 If max/min of cycles is known, reduction factors are shown in Figure Diagram for a simplified approach with cycles (Weyrauch diagram) Sd,fat max / N Rd F Sd,fat F Sd,fat max Sd,fat min / N Rd 0 time F Sd,fat min Figure 4.13: Reduction factors for fatigue for bond and concrete Hilti design software for rebar connections does also the fatigue design. If the simplified method is not satisfying, additional information using the Woehler - lines is available. Ask Hilti Technical Service for the Hilti Guideline: TWU-TPF 06a/02 Hilti HIT-Rebar: Fatigue / 2009

33 Basics of post installed rebar connections 1 /

34 Hilti HIT-RE 500 post installed rebars Hilti HIT-RE 500 post installed rebars Injection mortar system Benefits Hilti HIT-RE ml foil pack (also available as 500 ml and 1400 ml foil pack) Static mixer Rebar - suitable for non-cracked concrete C 20/25 to C 50/60 - high loading capacity - suitable for dry and water saturated concrete - under water application - large diameter applications - high corrosion resistant - long working time at elevated temperatures - odourless epoxy - embedment depth range: from mm for M8 to mm for M30 Concrete Fire resistance Fatigue European Technical Approval DIBt approval Drinking water appoved Corossion tested Marque NF Hilti anchor design software Hilti rebar design software Service temperature range Temperature range: -40 C to +80 C (max. long term temperature +50 C, max. short term temperature +80 C). Approvals / certificates Description Authority / Laboratory No. / date of issue European technical approval a) DIBt, Berlin ETA-08/0105 / DIBt approval DIBt, Berlin Z / Fire test report IBMB Braunschweig 3357/ / Assessment report (fire) Warringtonfire WF / a) All data given in this section according ETA-08/0105, issue / 2009

35 Hilti HIT-RE 500 post installed rebars Materials Reinforcmenent bars according to EC2 Annex C Table C.1 and C.2N. Properties of reinforcement Product form Bars and de-coiled rods Class B C Characteristic yield strength f yk or f 0,2k (MPa) 400 to 600 Minimum value of k = (f t /f y ) k 1,08 1,15 < 1,35 Characteristic strain at maximum force, ε uk (%) 5,0 7,5 Bendability Maximum deviation from nominal mass (individual bar) (%) Bond: Minimum relative rib area, f R,min Nominal bar size (mm) 8 > 8 Nominal bar size (mm) 8 to 12 > 12 Bend / Rebend test ± 6,0 ± 4,5 0,040 0,056 Setting details For detailed information on installation see instruction for use given with the package of the product. Curing time for general conditions Data according ETA-08/0105, issue Temperature of the base material Working time in which anchor can be inserted and adjusted t gel Initial curing time t cure,ini Curing time before anchor can be fully loaded t cure 5 C T BM < 10 C 2 h 18 h 72 h 10 C T BM < 15 C 90 min 12 h 48 h 15 C T BM < 20 C 30 min 9 h 24 h 20 C T BM < 25 C 20 min 6 h 12 h 25 C T BM < 30 C 20 min 5 h 12 h 30 C T BM < 40 C 12 min 4 h 8 h T BM = 40 C 12 min 4 h 4 h For dry concrete curing times may be reduced according to the following table. For installation temperatures below +5 C all load values have to be reduced according to the load reduction factors given below. Curing time for dry concrete Temperature of the base material Working time in which anchor can be inserted and adjusted t gel Additional Hilti technical data Initial curing time t cure,ini Reduced curing time before anchor can be fully loaded t cure Load reduction factor T BM = -5 C 4 h 36 h 72 h 0,6 T BM = 0 C 3 h 25 h 50 h 0,7 T BM = 5 C 2 ½ h 18 h 36 h 1 T BM = 10 C 2 h 12 h 24 h 1 T BM = 15 C 1 ½ h 9 h 18 h 1 T BM = 20 C 30 min 6 h 12 h 1 T BM = 30 C 20 min 4 h 8 h 1 T BM = 40 C 12 min 2 h 4 h 1 1 /

36 Hilti HIT-RE 500 post installed rebars Dry and water-saturated concrete, hammer drilling a) a ) Note: Manual cleaning for element sizes d 16mm and embedment depth h ef 20 d only! / 2009

37 Hilti HIT-RE 500 post installed rebars Dry and water-saturated concrete, diamond coring drilling; Hilti technical information only a) Note: Manual cleaning for element sizes d 16mm and embedment depth h ef 20 d only! Fitness for use Some creep tests have been conducted in accordance with ETAG guideline 001 part 5 and TR 023 in the following conditions : in dry environnement at 50 C during 90 days. These tests show an excellent behaviour of the post installed connection made with HIT-RE 500: low displacements with long term stability, failure load after exposure above reference load. 1 /

38 Hilti HIT-RE 500 post installed rebars Resistance to chemical substances Categories Chemical substances resistant Alkaline products Acids Solvents Products from job site Environnement Drilling dust slurry ph = 12,6 Potassium hydroxide solution (10%) ph = 14 Acetic acid (10%) Nitric acid (10%) Hydrochloric acid (10%) Sulfuric acid (10%) Benzyl alcohol Ethanol Ethyl acetate Methyl ethyl keton (MEK) Trichlor ethylene Xylol (mixture) Concrete plasticizer Diesel Engine oil Petrol Oil for form work Sslt water De-mineralised water Sulphurous atmosphere (80 cycles) Non resistant Electrical Conductivity HIT-RE 500 in the hardened state is not conductive electrically. Its electric resistivity is Ω.m (DIN IEC ). It is adapted well to realize electrically insulating anchorings (ex: railway applications, subway) / 2009

39 Hilti HIT-RE 500 post installed rebars Basic design data for rebar design according to ETA Bond strength Bond strength in N/mm² according to ETA for good bond conditions for hammer drilling, compressed air drilling, dry diamond core drilling Rebar (mm) Concrete class C12/15 C16/20 C20/25 C25/30 C30/37 C35/45 C40/50 C45/55 C50/60 8 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 10 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 12 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 14 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 16 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 18 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 20 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 22 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 24 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 25 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 26 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 28 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 30 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 32 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 34 1,6 2,0 2,3 2,6 2,9 3,3 3,6 3,9 4,2 36 1,5 1,9 2,2 2,6 2,9 3,3 3,6 3,8 4,1 40 1,5 1,8 2,1 2,5 2,8 3,1 3,4 3,7 4,0 1 /

40 Hilti HIT-RE 500 post installed rebars Bond strength in N/mm² according to ETA for good bond conditions for wet diamond core drilling Rebar (mm) Concrete class C12/15 C16/20 C20/25 C25/30 C30/37 C35/45 C40/50 C45/55 C50/60 8 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 10 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 12 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 14 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 16 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 18 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 20 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 22 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 24 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 25 1,6 2,0 2,3 2,7 3,0 3,4 3,7 4,0 4,3 26 1,6 2,0 2,3 2,7 2,7 2,7 2,7 2,7 2,7 28 1,6 2,0 2,3 2,7 2,7 2,7 2,7 2,7 2,7 30 1,6 2,0 2,3 2,7 2,7 2,7 2,7 2,7 2,7 32 1,6 2,0 2,3 2,7 2,7 2,7 2,7 2,7 2,7 34 1,6 2,0 2,3 2,6 2,6 2,6 2,6 2,6 2,6 36 1,5 1,9 2,2 2,6 2,6 2,6 2,6 2,6 2,6 40 1,5 1,8 2,1 2,5 2,5 2,5 2,5 2,5 2,5 Minimum anchorage length According to ETA-08/0105, issue , the minimum anchorage length shall be increased by factor 1,5 for wet diamond core drilling. For all the other given drilling methods the factor is 1, / 2009

41 Hilti HIT-RE 500 post installed rebars Minimum and maximum embedment depths and lap lengths for C20/25 according to ETA Diameter d s [mm] Rebar f y,k [N/mm²] Hammer drilling, Compressed air drilling, Dry diamond coring drilling l b,min * [mm] l 0,min * [mm] Wet diamond coring drilling l b,min * [mm] l 0,min * [mm] l max [mm] l b,min (8.6) and l 0,min (8.11) are calculated for good bond conditions with maximum utilisation of rebar yield strength f yk = 500 N/mm² and α 6 = 1,0 1 /

42 Hilti HIT-RE 500 post installed rebars Precalculated values Example of pre-calculated values for anchoring Rebar yield strength f yk = 500 N/mm², concrete C25/30, good bond conditions For all drilling procedures, excluding wet diamond core drilling (DD) Rebar Anchorage Design Mortar Anchorage Design Mortar length l bd value N Rd volume length l bd value N Rd volume [mm] [mm] [kn] [ml] [mm] [kn] [ml] α 1 =α 2 =α 3 =α 4 =α 5 =1.0 α 2 or α 5 = 0.7 α 1 = α 3 = α 4 = , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , * Values corresponding to the minimum anchorage length. The maximum permissible load is valid for good bond conditions as described in EN For all other conditions multiply by the value by 0,7. The volume of mortar correspond to the formula 1,2 (d 0 ²-d²) π lb/ / 2009

43 Hilti HIT-RE 500 post installed rebars Example of pre-calculated values for anchoring Rebar yield strength f yk = 500 N/mm², concrete C25/30, good bond conditions For all drilling procedures, excluding wet diamond core drilling (DD) Rebar Anchorage Design Mortar Anchorage Design Mortar length l bd value N Rd volume length l bd value N Rd volume [mm] [mm] [kn] [ml] [mm] [kn] [ml] α 1 =α 2 =α 3 =α 4 =α 5 =1.0 α 2 or α 5 = 0.7 α 1 = α 3 = α 4 = , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , * Values corresponding to the minimum anchorage length. The maximum permissible load is valid for good bond conditions as described in EN For all other conditions multiply by the value by 0,7. The volume of mortar correspond to the formula 1,2 (d 0 ²-d s ²) π lb/4 for hammer drilling 1 /

44 Hilti HIT-RE 500 post installed rebars Example of pre-calculated values for overlap joints Rebar yield strength f yk = 500 N/mm², concrete C25/30, good bond conditions For all drilling procedures, excluding diamond wet (DD) Rebar Anchorage Design Mortar Anchorage Design Mortar length l bd value N Rd volume length l bd value N Rd volume [mm] [mm] [kn] [ml] [mm] [kn] [ml] α 1 =α 2 =α 3 =α 5 =α 6 =1,0 α 2 or α 5 = 0,7 α 1 = α 3 = α 6 = 1, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Values corresponding to the minimum anchorage length. The maximum permissible load is valid for good bond conditions as described in EN For all other conditions multiply by the value by 0,7. The volume of mortar correspond to the formula 1,2 (d 0 ²-d s ²) π lb/4 for hammer drilling / 2009

45 Hilti HIT-RE 500 post installed rebars Example of pre-calculated values for overlap joints Rebar yield strength f yk = 500 N/mm², concrete C25/30, good bond conditions For all drilling procedures, excluding diamond wet (DD) Rebar Anchorage Design Mortar Anchorage Design Mortar length l bd value N Rd volume length l bd value N Rd volume [mm] [mm] [kn] [ml] [mm] [kn] [ml] α 1 =α 2 =α 3 =α 4 =α 5 =1.0 α 2 or α 5 = 0.7 α 1 = α 3 = α 4 = , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , * Values corresponding to the minimum anchorage length. The maximum permissible load is valid for good bond conditions as described in EN For all other conditions multiply by the value by 0,7. The volume of mortar correspond to the formula 1,2 (d 0 ²-d s ²) π lb/4 for hammer drilling 1 /

46 Hilti HIT-HY 150 post installed rebars Hilti HIT-HY 150 post installed rebars Injection mortar system Benefits Hilti HIT-HY ml foil pack (also available as 500 ml and 1400 ml foil pack) Statik mixer Rebar - suitable for concrete C 12/15 to C 50/60 - high loading capacity and fast cure - suitable for dry and water saturated concrete - for rebar diameters up to 25 mm - non corrosive to rebar elements - good load capacity at elevated temperatures - hybrid chemistry - suitable for embedment length till 2000 mm - suitable for applications down to - 5 C Concrete Fire resistance Fatigue DIBt approval Drinking water appoved Corossion tested Hilti anchor design software Hilti rebar design software Service temperature range Temperature range: -40 C to +80 C (max. long term temperature +50 C, max. short term temperature +80 C). Approvals / certificates a) Description Authority / Laboratory No. / date of issue DIBt approval a) DIBt, Berlin Z / Fire test report IBMB Braunschweig 3162/6989 / Assessment report (fire) Warringtonfire WF / The data given in this section are derived from DIBt Z issue and adapted to fit EC2 design method. Materials Reinforcmenent bars according to EC2 Annex C Table C.1 and C.2N / 2009

47 Hilti HIT-HY 150 post installed rebars Properties of reinforcement Product form Bars and de-coiled rods Class B C Characteristic yield strength f yk or f 0,2k (MPa) 400 to 600 Minimum value of k = (f t /f y ) k 1,08 1,15 < 1,35 Characteristic strain at maximum force, ε uk (%) 5,0 7,5 Bendability Maximum deviation from nominal mass (individual bar) (%) Bond: Minimum relative rib area, f R,min Nominal bar size (mm) 8 > 8 Nominal bar size (mm) 8 to 12 > 12 Bend / Rebend test ± 6,0 ± 4,5 0,040 0,056 Setting details For detailed information on installation see instruction for use given with the package of the product. Working time, Curing time Temperature of the base material T BM Working time t gel Curing time t cure * -5 C T BM < 0 C 90 min 9 h 0 C T BM < 5 C 45 min 4,5 h 5 C T BM < 10 C 20 min 2 h 10 C T BM < 20 C 6 min 90 min 20 C T BM < 30 C 4 min 50 min 30 C T BM 40 C 2 min 40 min * The curing time data are valid for dry anchorage base only. For water saturated anchorage bases the curing times must be doubled. 1 /

48 Hilti HIT-HY 150 post installed rebars Dry and water-saturated concrete, hammer drilling a) a) Note: Manual cleaning for element sizes d 16mm and embedment depth h ef 10 d only! / 2009

49 Hilti HIT-HY 150 post installed rebars Fitness for use Creep behaviour Creep tests have been conducted in accordance with national standards in different conditions: in wet environnement at 23 C during 90 days in dry environnement at 43 C during 90 days. These tests show an excellent behaviour of the post installed connection made with HIT-HY 150: low displacements with long term stabilisation, failure load after exposure above reference load. Resistance to chemical products HIT-HY 150 has been tested to its resistance to chemical products and the results are given in the table below: Chemical product Concentration First effects Resistance (in % of weight) (in days) Acetic acid Pure 6 o 10 % + Hydrochloric Acid 20 % + Nitric Acid 40 % < 1 - Phosphoric Acid 40 % + Sulphuric acid 40 % + Ethyl acetate Pure 8 - Acetone Pure 1 - Ammoniac 5 % 21 - Diesel Pure + Gasoline Pure + Ethanol 96 % 30 o Machine oils Pure + Methanol Pure 2 - Peroxide of hydrogen 30% 3 o Solution of phenol Saturated < 1 - Silicate of sodium 50% ph=14! + Solution of chlorine saturated + Solution of hydrocarbons 60 % vol Toluene; 30 % vol + Xylene 10 % vol Naphtalene of methyl Salted solution (sodium 10 % + chloride) Suspension of cement Saturated + Carbon tetrachloride Pure + Xylene Pure + We can retain that HIT-HY 150 behaves well as alkaline middle and that it is very resistant: in aqueous solutions in elevated ph (ex: silicate of sodium): no risk of saponification under weathering in salty solutions (ex: sea water) in solutions saturated in chlorine (ex: applications in swimming pool). Electrical conductivity HIT-HY 150 in cured state shows low electrical conductivity. Its electric resistivity is Ω.m (DIN VDE 0303T3). It suits well electrically insulating anchoring (ex: railway applications, subway). 1 /

50 Hilti HIT-HY 150 post installed rebars Basic design data for rebar design Bond strength Bond strength in N/mm² according to EC2 for good bond conditions for all drilling methods Rebar (mm) Concrete class C12/15 C16/20 C20/25 C25/30 C30/37 C35/45 C40/50 C45/55 C50/60 8 1,6 2,0 2,3 2,7 3,0 3,0 3,0 3,0 3,0 10 1,6 2,0 2,3 2,7 3,0 3,0 3,0 3,0 3,0 12 1,6 2,0 2,3 2,7 3,0 3,0 3,0 3,0 3,0 14 1,6 2,0 2,3 2,7 3,0 3,0 3,0 3,0 3,0 16 1,6 2,0 2,3 2,7 3,0 3,0 3,0 3,0 3,0 18 1,6 2,0 2,3 2,7 3,0 3,0 3,0 3,0 3,0 20 1,6 2,0 2,3 2,7 3,0 3,0 3,0 3,0 3,0 22 1,6 2,0 2,3 2,7 3,0 3,0 3,0 3,0 3,0 24 1,6 2,0 2,3 2,7 3,0 3,0 3,0 3,0 3,0 25 1,6 2,0 2,3 2,7 3,0 3,0 3,0 3,0 3,0 Minimum anchorage length The multiplication factor for minimum anchorage length shall be considered as 1,5 for all drilling methods. Minimum and maximum embedment depth and lap lengths Diameter d s [mm] Rebar f y,k [N/mm²] l b,min * [mm] Hammer drilling, Compressed air drilling l 0,min * [mm] lmax [mm] *l b,min (8.6) and l 0,min (8.11) are calculated for good bond conditions with maximum utilisation of rebar yield strength f yk = 500 N/mm² and α 6 = 1, / 2009

51 Hilti HIT-HY 150 post installed rebars Precalculated values Example of pre-calculated values for anchoring Rebar yield strength f yk = 500 N/mm², concrete C25/30, good bond conditions Rebar Anchorage Design Mortar Anchorage Design Mortar length l bd value N Rd volume length l bd value N Rd volume [mm] [mm] [kn] [ml] [mm] [kn] [ml] α 1 =α 2 =α 3 =α 4 =α 5 =1.0 α 2 or α 5 = 0.7 α 1 = α 3 = α 4 = , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , * Values corresponding to the minimum anchorage length. The maximum permissible load is valid for good bond conditions as described in EN For all other conditions multiply by the value by 0,7. The volume of mortar correspond to the formula 1,2 (d 0 ²-d²) π lb/4 1 /

52 Hilti HIT-HY 150 post installed rebars Example of pre-calculated values for overlap joints Rebar yield strength f yk = 500 N/mm², concrete C25/30, good bond conditions Rebar Anchorage Design Mortar Anchorage Design Mortar length l bd value N Rd volume length l bd value N Rd volume [mm] [mm] [kn] [ml] [mm] [kn] [ml] α 1 =α 2 =α 3 =α 5 =α 6 =1,0 α 2 or α 5 = 0,7 α 1 = α 3 = α 6 = 1, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , * Values corresponding to the minimum anchorage length. The maximum permissible load is valid for good bond conditions as described in EN For all other conditions multiply by the value by 0,7. The volume of mortar correspond to the formula 1,2 (d 0 ²-d s ²) π lb/ / 2009

53 Hilti HIT-HY 150 post installed rebars 1 /

54 Hilti HIT-HY 150 MAX post installed rebars Hilti HIT-HY 150 MAX post installed rebars Injection mortar system Benefits Hilti HIT-HY 150 MAX 330 ml foil pack (also available as 500 ml and 1400 ml foil pack) Static mixer Rebar - suitable for concrete C 12/15 to C 50/60 - high loading capacity and fast cure - suitable for dry and water saturated concrete - for rebar diameters up to 25 mm - non corrosive to rebar elements - good load capacity at elevated temperatures - hybrid chemistry - multiplication factor for minimum anchoring and splice length suitable for embedment length till 2000 mm - suitable for applications down to - 10 C Concrete Fire resistance Fatigue European Technical Approval CE conformity Drinking water appoved Corossion tested Hilti anchor design software Hilti rebar design software Service temperature range Temperature range: -40 C to +80 C (max. long term temperature +50 C, max. short term temperature +80 C). Approvals / certificates a) Description Authority / Laboratory No. / date of issue European technical approval a) CSTB, France ETA-08/0202 / Fire test report IBMB Braunschweig 3884/8246 / Assessment report (fire) Warringtonfire WF / All data given in this section according ETA-08/0202, issue Materials Reinforcmenent bars according to EC2 Annex C Table C.1 and C.2N / 2009

55 Hilti HIT-HY 150 MAX post installed rebars Properties of reinforcement Product form Bars and de-coiled rods Class B C Characteristic yield strength f yk or f 0,2k (MPa) 400 to 600 Minimum value of k = (f t /f y ) k 1,08 1,15 < 1,35 Characteristic strain at maximum force, ε uk (%) 5,0 7,5 Bendability Maximum deviation from nominal mass (individual bar) (%) Bond: Minimum relative rib area, f R,min Nominal bar size (mm) 8 > 8 Nominal bar size (mm) 8 to 12 > 12 Bend / Rebend test ± 6,0 ± 4,5 0,040 0,056 Setting details For detailed information on installation see instruction for use given with the package of the product. Working time, Curing time Temperature of the base material T BM Working time t gel Curing time t cure -10 C T BM < -5 C 180 min 12 h -5 C T BM < -0 C 90 min 9 h 0 C T BM < 5 C 45 min 4,5 h 5 C T BM < 10 C 20 min 2 h 10 C T BM < 15 C 7 min 50 min 15 C T BM < 20 C 6 min 40 min 20 C T BM < 25 C 5 min 30 min 25 C T BM < 30 C 3 min 30 min 30 C T BM 40 C 2 min 30 min 1 /

56 Hilti HIT-HY 150 MAX post installed rebars Dry and water-saturated concrete, hammer drilling a) a) Note: Manual cleaning for element sizes d 16mm and embedment depth h ef 10 d only! / 2009