GFRP systems for. for diaphragm walls and piles

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1 GFRP systems for for diaphragm walls and piles 0 U n d e r g r o u n d & C i v i l W o r k s d i v i s i o n

2 ATP is present in the FRP market for more than thirty years and it is today one of the leading company in the production of composite materials made out of carbon and glass. fibers. Field applications of such materials are spread and vary from transportation to energy, from chemistry to telecommunications. In the construction arena, the use of composites is getting more and more consensus among practitioners, contractors, and owners. Engineering and supplying Our services include strengthening of existing concrete members with FRP as well as the use of GFRP bars to replace steel in new concrete structures. The ATP team: prepares a preliminary design to be discussed with the engineer-of-record. ATP prepares the tender on the basis of the preliminary design. In case of green light by the engineer-of-record and following the material order to ATP will prepare the final document based on the comments suggested with the engineer-of-record. The final document will include the bill of material needed and the drawing of the GFRP cages. The specs: ACI 440.1R-06. ACI 440.3R- -Reinforced Polymers (FRPs) for. CNR-DT. (ACI, American Concrete Institute). (CNR, Italian National Research Council). 1

SOFT-EYES AND LARGE-DIAMETR ROUND PILES REINFORCED WITH GFRP BARS Introduction to Soft Eye Composite materials (FRP, Fiber Reinforced Polymer) are today widely used in applications related to

Originally developed in aeronautic-aerospace environment, they found a niche in the building material arena to be used as external strengthening of existing RC (Reinforced Concrete) structures and as

For the latter reason FRPs are mostly employed to replace steel reinforcement in harsh environment conditions.

3 SOFT-EYES AND LARGE-DIAMETR ROUND PILES REINFORCED WITH GFRP BARS Introduction to Soft Eye Composite materials (FRP, Fiber Reinforced Polymer) are today widely used in applications related to structural engineering. Originally developed in aeronautic-aerospace environment, they found a niche in the building material arena to be used as external strengthening of existing RC (Reinforced Concrete) structures and as steel-replacement in new RC members. Their principal advantages are high tensile strength, lightweight, and corrosion-free properties. For the latter reason FRPs are mostly employed to replace steel reinforcement in harsh environment conditions. One of the most used field application of FRP material is the replacement of steel reinforcing bars in RC members for the realization of subways and underground wastewater treatment systems. More in general, FRP is successfully used when RC members need to be drilled to allow the creation of underground lines by means of TBMs (Tunnel Boring Machines). The advantage of the combined used of FRP and TBM stems from the peculiar characteristic of FRP bars to be extremely resistant in the fiber direction and extremely easy to cut in the orthogonal direction. The term Soft-Eyes has been introduced to indicate those portion of the structures reinforced with FRP bars where a TBM will pass through. Soft-Eyes expedite boring operations and allow time and money saving during the realization of the line. 2

processes that involve removing materials

Fiberglass stirrup made of E-glass polyester

as a closed ring without joint or overlapping.

4 REBAR-ROCKWORM TM by ATP THE PRODUCT Fiberglass rebar made of E-glass polyester resin with improved external surface adherence obtained without milling or other processes that involve removing materials and/or reducing the resistant section. Fiberglass stirrup made of E-glass polyester resin with improved external surface adherence obtained without milling or other processes that involve removing materials and/or reducing the resistant section. A new generation stirrup: the stirrup is made as a closed ring without joint or overlapping. 3

Physical/Mechanical Properties Rockworm RWBp (polyester resin) Rebar diameter (mm) Minimum guaranteed Tensile

its value must be not less than 40 KN/mm 2 for GRP bars; the value is independent from dimension or shape of the

14 675 16 655 18 630 The tensile elastic modulus is derived from test samples as per ASTM D7205/D7205M specs;

The producer is obliged to report data of each test performed.

9 (ASTM D792) 26 540 28 525 30 505 32 480 40 450 50 450 Maximum bond stress to concrete 10,5 MPa Average value in

5 Physical/Mechanical Properties Rockworm RWBp (polyester resin) Rebar diameter (mm) Minimum guaranteed Tensile Strength (N/mm 2 ) Elastic Modulus The Tensile Elastic Modulus (nominal value) is given to certify the product; its value must be not less than 40 KN/mm 2 for GRP bars; the value is independent from dimension or shape of the cross section The tensile elastic modulus is derived from test samples as per ASTM D7205/D7205M specs; frequency and number of test samples is given in paragraph n 10 of the specs. The producer is obliged to report data of each test performed Glass fiber content: 70% (ASTM D2584) Specific gravity: 1.9 (ASTM D792) Maximum bond stress to concrete 10,5 MPa Average value in accordance to pull out test performed using testing method proposed in ACI440.3R-04. HOW COMPOSITES SHALL BE TESTED Tests for determining cross sectional properties. Tests for determining mechanical properties: Ultimate tensile strength. Ultimate tensile strain. Modulus of elasticity. GRP rebar before testing Typical rupture for GRP rebar 4

6 Some official laboratory test report Tensile strength test made following ACI 440 3R.04 recommendations Elastic moduls test made following ACI 440 3R.04 recommendations 5

7 Stirrups made of E-glass polyester resin with improved external surface adherence obtained without milling or other processes that involve removing materials and/or reducing the resistant section. Some available stirrups A [mm] B [mm] R=57 mm Minimum dimensions Maximum dimensions A new generation stirrup: the stirrup is made as a closed ring without joint or overlapping. 6

8 Design Design for Ultimate Limit State Flexure Shear Design for Service Limit State FRP Creep rupture Maximum concrete compressive stress Information needed for the design of GRP cages PROJECT NAME LOCATION OWNER NAME CONTRACTOR CONSTRACTION PERIOD TBM DIAMETER CONCRETE COMPRESSIVE STRENGTH NUMBER OF CAGES TO BE DESIGNED TYPE OF CONSTRUCTION (select with an x) GEOMETRY TBM LOCATION (see Fig. 1) MOMENT (see Fig. 2) SHEAR (see Fig. 2) CONTACT DIAPHRAGMS ROUND PILES OTHER diaphragms round piles other (please specify) width height thickness diameter height spacing please indicate member geometry upper limit lower limit ULS SLS ULS name telephone fax company 7

9 Design PROFONDITA' ,000-4,000-3,000-2,000-1, ,000 2,000 3, LATO SCAVO CONTRO TERRA MOMENTO O TAGLIO PERCORSO FRESA 5000 Legend Red Line Blue Line Black Line Magenta Line phimn [knm/m] f'c [MPa] Depth (m) ,000-4,000-3,000-2,000-1, ,000 2,000 3,000 Excavation Face Earth Face TBM Path phimn M n, M u (knm/m) 8

Handling and Placement Clamps/connectors (utilized to connect steel to fiberglass cages) To allow handling and

below); these plates should be utilized for hooking the assembled cage.

2000*200*20 mm. to fix n 15 couples of GRP 32 mm. diameter rods.

10 Handling and Placement Clamps/connectors (utilized to connect steel to fiberglass cages) To allow handling and positioning of GRP cages it is recommended to use some steel plates fixed to the cage at the ends (look at images below); these plates should be utilized for hooking the assembled cage. The images below represent an example of the application where the steel plates utilized have dimensions 2000*200*20 mm. to fix n 15 couples of GRP 32 mm. diameter rods. The clamps are composed by FE42 steel plates with dimensions 100*40*20 mm. with n 2 holes and n 2 M16 bolts welded to the plate to facilitate the assembly on job site. The assembly design is the one shown in the next figure. 9

Tests of clamps/connectors The pull out strength of a couple of clamps can be verified by applying a load scheme as

LLOYD T50K) and applying the load at the rate of 10 mm.

The nuts have been serrated with a dynamometric wrench set at 50-60 Nm.

1 An average value of 1200 kg has been calculated.

11 Tests of clamps/connectors The pull out strength of a couple of clamps can be verified by applying a load scheme as following: The tests have been performed by applying fixing the hook to the fixed plate of a dynamometer (type LLOYD T50K) and applying the load at the rate of 10 mm. per second; the load is measured utilizing a 50 KN load cell. The nuts have been serrated with a dynamometric wrench set at Nm. Number 5 tests have been run with the following results: Test n Max load (kn) An average value of 1200 kg has been calculated. To be noted that at reaching the maximum load values it has been experienced slipping of the GRP bars. The above indicated values should be utilized for the design and determination of the number of clamps necessary, obviously taking in the account the total weight of the cage. For the calculation a safety factor usually 3 should be applied. 10

Handling and positioning in site of assembled GRP cages. Handling to position the cages in place is performed by utilizing steel plates (see figure 9), bolted to the vertical rods (see figure 10).

The coupling of any two cages can be done by utilizing steel couplers which will rigidly clamp the bars (see figure 11).

12 Handling and positioning in site of assembled GRP cages. Handling to position the cages in place is performed by utilizing steel plates (see figure 9), bolted to the vertical rods (see figure 10). Figure 9 Detail handling steel plate. The positioning plates can be removed once the cage is in place. The coupling of any two cages can be done by utilizing steel couplers which will rigidly clamp the bars (see figure 11). In the figure we are showing a typical connection of n 2 cages either both GRP or one GRP and one steel. barrae interne tipo V-1 barrae esterne tipo V-1 barrae interne tipo V-1 barrae esterne tipo V-1 uncino di serraggio piastra metallica Figure 10 Positioning of lifting plates piastra metallica ganci di serraggio bulloni di fissaggio barre gabbia superiore manicotto in acciaio bulloni di fissaggio manicotto in acciaio barre gabbia inferiore barre gabbia superiore barre gabbia inferiore Figure 11 Detail of connection between 2 cages 11

13 V-1 gabbia 1 a) Sezione trasversale V-1 gabbia 2 V-1 gabbia 2 V-1 gabbia 1 b) Vista frontale Figure 12 Connection between cages, GRP/GRP GRP/STEEL 12

ATP Civil engineering, environmental engineering and geotechnical engineering projects and jobs are becoming more and more complex and operate at very large scale and needs of new cost effective and

14 ATP Civil engineering, environmental engineering and geotechnical engineering projects and jobs are becoming more and more complex and operate at very large scale and needs of new cost effective and environmental friendly solution are required. The value of the overall project is no longer bound only to the quality of the single components, i.e. to smart engineering solution and single simple product, but also to an efficient coordination of the overall process and to the capacity of finding quickly the most convenient solution and strongly related to cooperation between engineering and industry. Efficient coordination and knowledge brokerage services require a deep insight in the engineering domain, in industrial product availability and in informatics technologies capable of deliver services and cross-link the designer-industry-client market. The peculiarities of the ATP Group is a fortunate mix of know-how perfectly corresponding to the market needs: Flexible and dynamic R&D department. Flexible and dynamic Production. Reactive-Search and development of new products based on effective needs of the market. ATP aims at offering new solutions to construction market applying the latest technologies available in composite FRP materials. ATP desires to establish a valuable worldwide connection becoming a reference point for FRP composite solutions in the construction market. ATP s.r.l. via Casa Pagano, Angri (SA) Italy ph (pbx) - fax underground@atp.sa.it - 13

SOFT EYE. TBM passage through. RWB rebar. U n d e r g r o u n d & C i v i l W o r k s d i v i s i o n

SOFT EYE. TBM passage through. RWB rebar. U n d e r g r o u n d & C i v i l W o r k s d i v i s i o n SOFT EYE TBM passage through RWB rebar U n d e r g r o u n d & C i v i l W o r k s d i v i s i o n TBM breaking through GFRP Reinforced Wall The typical application is the so-called soft-eye. When the