RSMA COMPLIANCE STANDARD FOR TRAFFIC SIGNS 2008

Transcription

1 2008

2 RSMA COMPLIANCE STANDARD FOR TRAFFIC SIGNS 2008 DETAILS OF DOCUMENT AMENDMENT No.1 (16/03/2010) Section amended Description of amendment A (iii) Reference to CHS posts added Note 2 Reference to Post Selection Charts added with required finishing for steel posts. Charts B3 & B7 Post sizes amended to readily available sizes Copyright Road Safety Manufacturers Association All rights reserved. Parts may be copied with permission.

3 ALL IMPORTANT NOTE FOR THE READER This document (2008 Copyright) supersedes all previous publications and is available electronically on the RSMA website ( While this document is believed to be correct at the time of publication, The Road Safety Manufacturers Association (RSMA) and their employees or agents involved in its preparation and publication cannot accept any liability for its contents or for any consequences arising from its use. Users of the document and its contents should apply and rely on their own skill and judgement along with other sources of information and advice. The Standard will be updated periodically to incorporate advances in technology and changes within the industry and so the RSMA website may be checked to ensure copies of the Standard are current.

4

5 ROAD SAFETY MANUFACTURERS ASSOCIATION MISSION STATEMENT The Road Safety Manufacturers Assn (RSMA) is a non-profit, non-political service organisation promoting excellence and best practice regarding road safety on the roading infrastructure in New Zealand by setting and raising industry standards. GOAL Our goal is to foster the implementation of road safety initiatives of the Minister of Transport, Transit New Zealand, Land Transport New Zealand, the Police and other road safety organisations and to provide the appropriate professional support. RSMA MEMBERS A list of current RSMA members is published on the RSMA website ( Road controlling authorities and contractors relying on the members' authenticity and credibility should refer to the list on the website for proof of membership.

6 CONTENTS MISSION STATEMENT GOAL RSMA MEMBERS 1 SCOPE RELATED DOCUMENTS DEFINITIONS DESIGN Signface Wind Resistance Sign Supports MANUFACTURING Materials for Sign Substrates Materials for Posts UV Stabilised Plastics Sign Blanks Stiffening Preparation and Painting Application of Retroreflective Sheeting Imaging Post Caps Brackets and Fittings Fabrication Tolerances Identification Marking Street Name Signs INSTALLATION Packing and Handling Positioning Foundations and Location Assembly MAINTENANCE Cleaning Repairs... 17

7 8 COMPLIANCE Alternative Means of Compliance Right of Review APPENDICES: Appendix A : Stiffening of Non-Directional Permanent Warning and Regulatory Signage Appendix B : Post Selection Charts for Small Signs Appendix C : Foundation Selection Tables for Small Signs Appendix D : Worked Sample Using Post & Foundation Selection Charts in Appendices B & C

8 1 SCOPE This standard was compiled by the Road Safety Manufacturers Association (RSMA) as a means of compliance document for the Transit New Zealand Performance Based Specification for Traffic Signs (TNZ P/24). The Transit TNZ P/24 Specification is performance based and so does not prescribe features that signs must have to comply, but rather the performance levels that signs must meet. This Standard prescribes materials and designs that are deemed to comply with the Transit New Zealand Performance Based Specification for Traffic Signs, TNZ P/24, and provides a standard for the manufacture and installation of street name signs. The Standard does not give complete coverage of all possible materials, designs and components, but describes current industry practice and existing sign systems that have proved to have satisfactory performance. Notwithstanding the contents of this document, all signs and installations shall comply with current legal requirements. Page 1

9 2 RELATED DOCUMENTS AASHTO LTS-4-M AS 1163:1991 Standard Specifications for Structural Supports for Highway Signs, Luminaries and Traffic Signals, 4 th Edition Structural steel hollow sections AS/NZS 1170 Structural design actions Parts 0 to 3, 5 AS/NZS :2004 AS/NZS 1734:1997 AS/NZS 1866:1997 AS/NZS1906.1:2007 NZS 3460:2003 AS/NZS 3678:1996 AS/NZS :1996 NZS 4711:1984 AS/NZS 4680:2006 AS/NZS 4792:2006 BS8442:2006 Manual of Traffic Signs and Markings (MOTSAM) Traffic Control Devices Manual TNZ P/24 SHGDM NCHRP 350 Part 1 Structural steel welding - Part 1: Welding of steel structures Aluminium and aluminium alloys Flat sheets, coiled sheet and plate Aluminium and aluminium alloys Extruded rod, bar, solid and hollow shapes Retro reflective materials and devices for road traffic control purposes - Retro reflective sheeting Chemical preservation of round and sawn timber Structural steel Hot-rolled plates, floor plates and slabs Structural steel Hot-rolled bars and sections Qualification Tests for Metal Arc Welders Hot-dip galvanised (zinc) coatings on fabricated ferrous articles Hot-dip galvanised (zinc) coatings on ferrous hollow sections, applied by a continuous or specialized process Miscellaneous road traffic signs and devices. Requirements and test methods Transit New Zealand/Land Transport New Zealand Land Transport New Zealand Performance Based Specification for Traffic Signs, Transit New Zealand State Highway Geometric Design Manual The National Cooperative Highway Research Project Page 2

10 3 DEFINITIONS Breakaway Support Clear Zone Intended Life Hinge All Types of sign supports that are designed to safely yield, fracture or separate (at or near ground level) when impacted by a vehicle, thereby minimising injury to the occupants of the vehicle and damage to the vehicle. The clear zone is the desirable unobstructed roadside area available for errant vehicles to recover or come to rest safely. The intended life is the period of time a sign shall meet the performance requirements specified, and includes the effects of normal environmental degradation expected at the site, but excludes accidental or wilful damage and the effects of extreme weather events beyond accepted criteria. The weakened section of a sign support designed to allow the post to rotate when impacted by a vehicle. Large Traffic Sign Roadside sign with sign area greater than 4.7m 2 MOTSAM AS/NZS 1170 Posts Signs Manual of Traffic Signs and Markings, Part 1: Traffic Signs, Transit New Zealand / Land Transport Structural design actions A post shall consist of a tube or hollow or solid section to which the traffic sign is attached. In these notes the word sign shall be interpreted as including all the components that make up a sign, including the foundation, support posts, sign panel, brackets, fittings and fastenings. Small Traffic Sign Roadside sign with sign area less than or equal to 4.7m 2 Specification Standard In this standard the word Specification shall be interpreted as referring to the Transit New Zealand Performance Based Specification for Traffic Signs (TNZ P/24). The word Standard shall be interpreted as a reference to this RSMA Compliance Standard for Traffic Signs. Page 3

11 4 DESIGN 4.1 Signface The signface design, including dimensions, lettering, legends, colour and retroflectivity, shall comply with MOTSAM and the LTNZ Traffic Control Devices Manual. 4.2 Wind Resistance The design of the support system shall comply with wind load criteria and other structural requirements in the Specification Wind Resistance Design - Posts Multiple mount signposts are required where the sign area or width is too large for the resistance of the environmental loads with a single post. Multiple posts are normally required for any sign greater than 1.3m wide. Where two-post mounting is required, it is good practice in minimising wind deflection to place the posts equidistant from each end by one-sixth (1/6) or one- fifth (1/5) of the overall sign width. Multiple post mounting shall be restricted to the minimum number of posts required to install the sign compliant with the specification and standard. Timber, steel and aluminium posts dimensions are provided as a guide for common sign configurations, in Appendix B. Charts 1 to 8 are included in Appendix B for the selection of typical post sizes for signs with panel area less than or equal to 4.7m 2 located at the roadside. The charts for the regional wind speed of 45m/s apply to Wellington and the Marlborough Sounds (Region W). The charts for a regional wind speed of 39m/s apply to all other regions (Regions A6 & A7). Wind Regions of New Zealand are identified in Figure 3.1 of AS/NZS Wind Actions. Design to AS/NZS1170 is required for signs at elevations greater than 500m above sea level, in steep terrain, or signs with dimensions not covered by these charts (see chart notes). The charts show typical solutions for a range of materials and cross-section shapes but are not intended to restrict the designer if other materials and cross-section shapes are available provided the design is based on AS/NZS1170 and the factors adopted in the Specification Foundation Design An acceptable method for the design of foundations for posts embedded in the ground, or in bored concrete footings is the Broms method (as presented by H. Poulos and E. Davis, 1980). Tables 1 to 8 are included in Appendix C for the selection of appropriate embedment depths for cast in-situ concrete cylindrical footings in a range of soils based on the Broms method. Table 8 is included for the selection of shallow pad footings in areas where underground services are an issue. The tables are based on a soil strength reduction factor of 0.6. Specific foundation design is required for foundations in soils outside the indicative parameters given in the tables and for large signs with a panel area greater than 4.7m 2 or all signs over a carriageway. Where not specifically designed, the minimum support post planting depth shall be one fifth of the mounting height, but not less than 1 metre depth. Page 4

12 4.3 Sign Supports The following detail refers to Guide, Motorist Service, Tourist and Road Safety Campaign Signs. These Traffic Signs are divided into three main categories: overhead signs, small roadside signs with a sign area less than or equal to 4.7m 2 and large roadside signs with a sign area exceeding 4.7m 2. The hardware and corresponding safety treatment of sign supports varies with the sign category Design Life of Sign Supports The intended design life of sign support structures shall be: Overhead Signs, VMS signs Large Roadside Signs (greater than 4.7m 2 ) Small Roadside Signs (less than or equal to 4.7m 2 ) 50 years 25 years 10 years Overhead Signs Where possible, overhead signs shall be installed on nearby overpasses or other existing structures. Overhead signs, including cantilevered signs, generally require significant support systems that cannot be made breakaway. All overhead sign supports located within the clear zone shall be specifically designed to AS/NZS1170 and be shielded behind a compliant safety barrier system Small Traffic Signs Defined as those signs having a sign panel area less than or equal to 4.7m2 supported on one or two posts and installed less than 500m above sea level. Signs installed 500m above sea level require specific design and are treated under below. Each post shall have a mass less than 25kg/m (a) Single Post Installation. Subject to the requirements of 5.5.1(Aluminium Channel Stiffening Sections) and Appendix B (Post selection Charts for Small Signs), generally signs under 1.3m wide shall be installed on a single breakaway support. Refer to Sign Support Selection Chart for details of sign mounting height, compliant Breakaway Supports and foundation details. (b) Multi Post Installation. Subject to the requirements of 5.5.1(Aluminium Channel Stiffening Sections) and Appendix B (Post Selection Charts for Small Signs), signs over 1.3m wide and with a sign panel area less than or equal to 4.7m 2 shall be installed on a two breakaway supports spaced no further than 2.1m apart. Refer to Sign Support Selection Chart for details of sign mounting height, compliant Breakaway Supports and foundation details Large Traffic Signs Defined as those signs supported on two or more posts that:- (i) (ii) have a sign panel area exceeding 4.7m 2 and/or are installed 500m above sea level and/or Page 5

13 (iii) are installed on posts greater than 2.1m apart. Specific Design is required for breakaway supports refer Schedule B Impact Performance in Urban Areas The road controlling authority may decide that in specific situations the risk of injury to pedestrians from breakaway sign posts exceeds that of the vehicle occupants, in the event of a crash, and so specify that Section 9 of the Specification does not apply. Examples of sites where breakaway supports may be imprudent are adjacent to bus shelters or in areas of pedestrian concentrations Sign Support Selection Chart SIGN TYPE Regulatory Permanent Warning MOUNTING HEIGHT* Rural - not < 1.5m Urban - not < 2.0m Over footpath not < 2.5m No. OF SIGN SUPPORTS 1 COMPLIANT SIGN SUPPORTS Refer Schedule A POST SELECTION Appendix B FOUNDATION DESIGN Appendix C SMALL SIGNS less than 1.3m wide Guide Motorist Service Tourist Road Safety Campaign Rural - not < 1.5m Urban - not < 2.0m Over footpath - not < 2.5m (exception is low mounted Traffic Island IDS signs) 1 Refer Schedule A Appendix B Appendix C SMALL SIGNS - 4.7m 2 & sign supports < 2100mm apart. Installed < 500m above sea level Guide Motorist Service Tourist Road Safety Campaign Not < 2.1m Over footpath - Not < 2.5m (exception is low mounted Traffic Island IDS signs) 2 Refer Schedule A or Schedule B LARGE SIGNS - >4.7m 2 &/or sign supports > 2100mm apart &/or installed over 500m above sea level. Guide Motorist Service Tourist Road Safety Campaign Not < 2.1m Over footpath - not < 2.5m 2 + Refer Schedule B Appendix B Supplied with Schedule B approved products or part of specific design to NZS1170 Appendix C Foundations require specific design. * Mounting Height is measured from underside of sign to surface of adjacent road, trafficable shoulder or top of kerb. Page 6

14 4.3.7 Sign Supports Deemed to Comply with Impact Requirements Schedule A Signs that are constructed within the limitations of this section are deemed to comply with Clause 9.1 of the Specification for Small Traffic Signs: (i) Timber posts 1 (Radiata Pine No: 1 framing, H4 treatment) not exceeding size 100mm x 100mm direct embedment or 125mm diameter posts (Radiata Pine No. 1 framing, H4 treatment) without further treatment. (ii) Timber posts 1 (Radiata Pine No: 1 framing, H4 treatment) not exceeding 100mm x 150mm treated with 40mm diameter holes, 150mm x 150mm treated with 50mm diameter holes and 100mm x 200mm and 150mm x 200mm treated with 75mm diameter holes. Holes to be drilled perpendicular to traffic direction and located 100mm and 460mm above ground level. (iii) Steel posts 1, 2 CHS (circular hollow section) not exceeding 76mm outer diameter and wall thickness 3.2mm, Grade 350, or RHS (rectangular hollow section) 75mm x 50mm outer dimension x 3.0 mm wall thickness, Grade 350. (iv) Aluminium posts 1 manufactured in grade 6261-T5 (255MPa yield strength) not exceeding mm outer diameter with a maximum wall thickness of 4.7mm. (v) Sign supports listed as an approved system under the FHWA Roadside Hardware Acceptable Breakaway Sign Supports listing. (Refer to the FHWA Web Page). Schedule B Signs that are constructed within the limitations of this section are deemed to comply with Clause 9.1 of the Specification for Small and Large Traffic Signs and shall be achieved by: (i) specific design to NZS1170 or (ii) utilising breakaway supports that conform to AASHTO 2001 Standard Specifications for Structural Supports for Highway Signs, Luminaires and Traffic Signals and have been crash tested and FWHA approved in accordance with the requirements of NCHRP350 Test Level 3 (Refer to FWHA Web Page) or (iii) an approval using an alternative means of compliance, as described in Section The following limitations shall apply:- (a) The sign support manufacturer shall provide a post selection formula based on Structural Performance, Breakaway Dynamic Performance, Wind Loading design and Design Life The embedment type for timber posts and the maximum size specified for steel and aluminium posts is based on published FHWA test data. This section relates to the maximum wall thickness/tensile strength that is deemed to comply with Impact Requirements. In order to provide the end user with a sign post that meets these requirements and is readily available, Post Section Charts are provided in Appendix B for steel CHS posts 60 and 76mm outer diameter, wall thickness 2mm, Grade 350. Suppliers of posts outside these properties will have to provide separate Post Selection Charts. All posts shall be galvanised and powder coated to meet the 10 year design life requirements for small signs. NCHRP accept a maximum of 102mm outer diameter. This Standard accepts a maximum of 114mm outer diameter following a determination vide Section 8 of this Standard. Page 7

15 (b) An approved hinge device shall be fitted immediately below the sign panel. No supplementary signs shall be attached below the hinges if such placement is likely to interfere with the breakaway action of the support post or if the supplemental sign is likely to penetrate the windshield of an impacting vehicle. (c) Each post shall have a mass no greater than 65kg/m. The total mass below the hinge but above the shear plane of the breakaway base device, shall not exceed 270kg. (d) The minimum mounting height to the underside of the sign shall be 2.1m. (Note: Although MOTSAM allows a minimum mounting height that in some circumstances is less than 2.1m, such signs do not qualify as deemed to comply with the requirements of the Specification). (e) Breakaway base devices must not be located more than 100mm above the average ground level within 1.5m of the sign post. Refer Section 6.3. (f) Multi (Omni)-Directional breakaway devices should be used where impact from any direction is possible. Inclined Slip Base Breakaway devices shall not be used. (g) Sign Stiffening Channel spacing shall be calculated in accordance with the manufacturers recommendations relating to post centres and overhang to comply with deflection requirements of the Specification. Page 8

16 5 MANUFACTURING 5.1 Materials for Sign Substrates Materials used for signs shall be in accordance with the following standards as well as comply with current legislation. (a) Aluminium: NZS/AS1734:1997 Wrought aluminium and aluminium alloys- Flat sheets, coil sheet and plate. (b) UV Stabilised Plastic: BS8442:2006 Miscellaneous road traffic signs and devices. Requirements and test methods (c) Retroreflective Sheeting: AS/NZS1906.1:2007 Retroreflective materials and devices for road traffic control purposes - retroreflective sheeting. Preparation and application of retroreflective sheeting shall be as per the sheeting suppliers warranty conditions. (Note: The LTSA Gazette Notice in itself does not constitute compliance with AS/NZS ). Materials and finishes shall be compatible so as to avoid failure or deterioration due to electrolytic action or by differential thermal expansion. Alloys and finishes containing copper shall not be used in contact with aluminium alloys. 5.2 Materials for Posts Posts shall be manufactured from one of the following materials: (a) Timber Posts: Timber posts shall conform to: NZS 3631: 1998 New Zealand Timber Grading Rules, No.1 framing grade, H4 treatment, dried to 20% to 24% moisture content. NZS 3640:2003 Chemical Treatment of Round and Sawn Timber, Hazard Class H4 The timber finish may be gauged or dressed, and shall be primed and finished with high gloss white paint above ground level. (b) Steel Posts: Steel posts shall conform to: AS 1163:1991 Structural steel hollow sections AS/NZS :2004 Structural steel welding - Welding of steel structures AS/NZS 3678:1996 Structural steel Hot-rolled plates, floorplates and slabs AS/NZS :1996 Structural steel Hot- rolled bars and sections AS/NZS 4680:2006 Hot-dip galvanised (zinc) coatings on fabricated ferrous articles NZS 4711:1984 Qualification Tests for Metal Arc Welders AS/NZS 4792:2006 Hot-dip galvanised (zinc) coatings on ferrous hollow sections, applied by a continuous or a specialized process Page 9

17 (c) Aluminium Posts: Aluminium posts shall conform to: AS/NZS 1866:1997 Aluminium and aluminium alloys Extruded rod, bar, solid and hollow shapes. To alloy 6261 T5 or equivalent. 5.3 UV Stabilised Plastics (a) When tested under conditions of either: (i) continuous natural exposure for 2 years, or (ii) accelerated weathering for 1200 hours, using the procedure described in BS 8442:2006, samples of the material shall show no sign of deterioration such as cracking, scaling, pitting, blistering, delamination, distortion, staining or chalking. (b) When subjected to the action of a saline mist as described in BS 8442:2006, there shall be no sign of colour change. (c) When subjected to the action of a saline mist as described in BS 8442:2006, Part 1, there shall be no sign of deterioration, corrosion, or evidence of colour change. (d) When subjected to the impact test specified in BS 8442:2006, the sample shall not be deformed at any point by more than 2mm from the plane surface and any cracking or other damage shall be confined within a circle of 5mm radius around the point of impact of the steel ball. 5.4 Sign Blanks Materials The recommended substrate for all sign blanks shall: (a) be constructed from aluminium sheet grade 5251-H34 as referred to in AS/NZS 1734:1997 or equivalent and be a minimum thickness of 2mm over 0.36m 2 stiffened or 2.5mm up to 0.9m 2 unstiffened; (b) be stiffened in accordance with Section Joints Shall be constructed such that the number of sheets be kept to a minimum and the separate sheets be rectangular and approximately the same size and shape. (i) Horizontal panel joints shall not occur through any internal border, or through any word or numeral legend of character height 100mm or less other than the descenders of any lower case legend. (ii) Vertical joints shall be located so as not to have any legend directly over the joint. (iii) Where there are two or more parallel joints in a blank, the centre panel or panels so formed shall not be narrower than the outside panels. Horizontal Joints A length of channel stiffening section as specified in section 5.5 below, terminating 20 ± 5mm short of the edge of the sign may be considered as part of the horizontal bracing when used to cover the joint. Page 10

18 Vertical Joints The backing for vertical joints shall be a cover strip of the same material as the blank, 60 ± 5mm wide, terminating 10 ± 5mm short of the edge of the sign and discontinued at each horizontal stiffening section or cover strip with a gap not exceeding 5mm. A cover strip over a vertical panel joint may be omitted if the calculated length of the cover strip would be less than 100mm. The backing shall be attached to each blank sheet, either by a single row of rivets evenly spaced across the sign at a spacing not exceeding 300mm with an edge distance not exceeding 30mm from the end of the cover strip. A fixing system of equivalent strength and durability may be used. All cover strips shall be coloured on both sides with the same matt colour as the back of the sign. 5.5 Stiffening Aluminium Channel Stiffening Sections All channel extrusions shall be extruded from alloy 6261-T5 or equivalent as referred to in AS/NZS 1866:1997 Aluminium and aluminium alloys. Where channel extrusions form an integral part of the sign blank, they must be firmly attached. Attachment of channel extrusions to aluminium blanks should be by means of 3mm carbon steel and mechanically zinc plated blind rivets fixed through the sign face. Where rivet heads are exposed, the rivet heads shall be coloured to match the sign background. The maximum distance between adjacent rivets shall be not more than 200mm with rivets spaced equally across the sign face except at each end of the channel 2 rivets shall be spaced within 30mm of each other. Alternatively, fixing systems of equivalent strength and durability may be used. Where a sign is required to be finished with unexposed rivet heads, they shall be fitted flush with the sign face. Channel extrusions are to be attached prior to the application of retroreflective sheeting, using either 3mm carbon steel and mechanically zinc plated blind rivets or counter sunk blind rivets of equivalent strength and durability. Alternatively, fixing systems of equivalent strength and durability may be used. Channel extrusions on signs under 6100mm in width must be continuous across the sign blank without breaks or joints, with extrusions terminating not more than 50mm from the edge of the sign. Channel extrusions on signs over 6100mm in width may be joined using an approved channel coupling as per the manufacturer's specification. All channel-stiffening sections adjacent to support posts must be secured by methods given in section 5.10 below. Channel spacing in conjunction with post centres shall be calculated in accordance with manufacturer's recommendations and conform to deflection requirements of the Specification. Channel manufacturers shall make available engineering calculations and channel/post spacing charts with calculations conforming to NZS 4203 if requested Stiffening of non-directional Permanent Warning and Regulatory Signage Stiffening of all panels shall consist of no less than 2 channel extrusions fixed horizontally across the back of the sign, as per the channel manufacturer's recommendations. Typical drawings are provided in Appendix A. Stiffening is to terminate no less than 50mm from each edge of the sign panel with rivets being spaced no more than 200mm equally across the sign Page 11

19 face. In addition, 2 rivets within 30mm of each other are required at channel ends. Alternatively, fixing systems of equivalent strength and durability may be used. 5.6 Preparation and Painting Paint or alternative powder coating used for traffic signs shall be of proven quality consistent with the intended life of the sign. (a) Aluminium sign blanks shall be prepared for painting in accordance with the paint supplier s specifications. Generally sign blanks shall be degreased and oil free etched with self-etching primer or phosphating process. (b) All sign blanks for reflectorised signs shall be prepared in accordance with the retroreflective sheeting manufacturer s specifications. (c) Unless otherwise specified, all panel backs shall be coloured aircraft grey (colour standard Pantone PMS 431) or similar and the finish to be semi-gloss to reduce the effects of specular glare. 5.7 Application of Retroreflective Sheeting Retroreflective sheeting shall be applied to properly prepared blanks by the squeeze roll applicator process. Edges shall be knife trimmed from the face side and cut cleanly and level to the sign panel without overhang. As far as possible retroreflective sheeting should cover the sign panel in one piece. However, if this is not possible, joints should be vertical or horizontal and should overlap by a minimum of 10mm. When horizontal joints overlap, the overlap shall be from the top. Care must be taken in the application of retroreflective sheeting as it should be applied in accordance with the sheeting manufacturer s recommendations. 5.8 Imaging All legends, symbols and borders may be applied by the silk screening process, either before or after application of the sheeting to the flat base panels. To ensure complete compatibility and durability, all process inks, clear coats etc used shall be supplied or recommended by the sheeting manufacturer and applied in a manner as specified by the sheeting supplier. As an alternative process, legends, symbols and borders may be fabricated by an overlay process. Where reflective or non-reflective materials are used in this overlay process, those materials used must be consistent with the intended life of the sign as contained in the Specification. 5.9 Post Caps Post caps shall be manufactured from steel, aluminium or plastic. Post caps shall be the same colour as the posts. Post caps are not required for timber posts Brackets and Fittings Fittings shall be manufactured from durable materials i.e. stainless steel type AISI 201 or 304, cast or extruded aluminium, or steel galvanised to AS/NZS 4680:2006 after manufacture. Fittings finished in zinc or electroplated are not to be used. Brackets and fittings shall form an integral part of the stiffening structure where this is provided on the sign blank. All channel extrusions passing a sign support must have the correct sized and shaped bracket fitted. Page 12

20 Where no stiffening structure is provided the sign shall be bolted, riveted or attached with special purpose fixing systems of equivalent strength and durability directly to the sign plate. Hex head bolts shall not be used in stiffening channel. Bracket manufacturers shall make available engineering calculations including torque settings and failure loads if requested. All brackets and fittings shall be installed to the bracket and stiffening channel manufacturers instructions Fabrication The height or width of the sign blank may be adjusted by a maximum of ±5.0% of the original designed dimension to allow efficient use of raw materials. This adjustment may not be applied to symbols, lettering or any other elements of the signface. Sign plates and extrusions, including cutting, rounding of corners, and punching of holes shall preferably be completed prior to degreasing, etching and the application of the retroreflective sheeting or painting Tolerances Unless otherwise specified on the drawings tolerances on blank dimensions shall be as follows: (a) Overall dimensions of blank (including any dimension adjusted as per section 5.11): ± 3mm or 0.5 percent of dimension, whichever is the greater. (b) Holes: Size, tolerance - 0, + 1mm. Hole centre dimension (geometric position): mating hole centres, tolerance ± 1mm. Nonmating hole centres, tolerance ± 3mm. (c) Maximum allowable warp, twist or departure from flatness, except for any departures prescribed by the drawing to increase stiffness: 3mm/metre. (d) Blank squareness: In the case of a single panel sign, no corner of the panel shall be more than 2mm from its theoretical position relative to other corners. In the case of multi-panel signs, adjacent panels shall be rectangular and fit together so that any gap between panels is not less than 1.0mm and not more than 1.5mm wide along the edge of the join. (e) All permanent signs to have radius corners finished in accordance with sign layouts. (f) All edges shall be smooth and true. Page 13

21 5.13 Identification Marking All signs shall be permanently identified on the back of the sign with the manufacturer s name, month and year of manufacture. The label shall enable the manufacturer to trace the retroreflective sheeting manufacturer's name, and class of sheeting. Identification marking size shall be a maximum of 5000mm 2 durability as the intended life of the sign. and shall be of the same 5.14 Street Name Signs Materials Street Name signs shall be constructed using Materials and Stiffening as per and 5.5. or alternatively: A purpose designed, one piece, " I " section aluminium extrusion manufactured from alloy 6106-T6 or equivalent as referred to in AS/NZS 1866:1997. The thickness of the web of the " I " extrusion shall be no less than 2.5mm. The depth of the " I " extrusion shall be the measurement of the flat surface available for the application of the sign background surface. This measurement is referred to as the "target/reflective depth". The maximum length of cantilevered Street Name Signs shall be as per the bracket manufacturers specifications Brackets and Fittings Brackets and Fittings shall comply with requirements of There shall be a minimum of two (2) brackets per sign (one each top and bottom). Page 14

22 6 INSTALLATION 6.1 Packing and Handling All signs shall be packed and handled in accordance with the retroreflective sheeting manufacturer s recommendations and in all cases signs shall arrive at their destination in new condition. At all stages prior to installation, signs shall be stored on edge and handled in a careful manner to avoid damage, and the recommendation of the sheeting manufacturer shall be followed at all times. At no time during storage at the manufacturing plant, or during delivery, shall packs of signs be allowed to become wet. To avoid damage resulting from moisture, signs should not be stored in their packaging materials. 6.2 Positioning Signs shall be positioned and mounted to comply with New Zealand legal requirements and MOTSAM. Where discretion is available within these requirements regarding the location, orientation and mounting of a sign, the State Highway Geometric Design Manual shall be used, with due regard to visibility, safety and maintenance peculiarities of the site. Ground Installation On tangent sections, position signs so that the vertical axis is plumb, and the horizontal axis is at an angle of 95 with the traffic lane which the sign serves as referred to in Section 1.10 of MOTSAM. On horizontal curve sections, position the sign so that the vertical axis is plumb and the horizontal axis is at an angle of 95 with a straight line between the sign and the point at which the sign is to be read. Support structures shall be permanently secured and free standing in the ground in accordance with Section 8.4 of the Specification, without supplementary props or supports. Overhead Signs Where the road gradient approaching the sign is +2.0% or greater, position the sign so the vertical axis is parallel to a plumb-line and the horizontal axis is at right angles to the road. Where the road gradient approaching the sign is less than +2.0%, the sign should be positioned so its horizontal axis is at a right angle to the road, and the vertical axis of the signface is inclined to face upward at a rate of 3mm per 300mm of vertical sign surface for each one percent the road gradient differs from +2.0%. Cleaning considerations Careful siting may reduce the fouling of a sign and consequent maintenance/cleaning costs. Full advantage of the height range allowable in the Transit New Zealand/Land Transport Safety Authority Manual of Traffic Signs and Marking should be taken to keep signs above traffic spray. Page 15

23 6.3 Foundations and Location Sign supports shall be carefully located to ensure that the breakaway devices perform properly and to minimise the likelihood of impacts by errant vehicles e.g. sign supports should not be placed in drainage ditches where erosion and freezing might affect proper operation of the breakaway mechanism. Supports placed on roadside slopes shall not allow impacting vehicles to snag on either the foundation or any substantial remains of the support. Surrounding terrain shall be graded to permit vehicles to pass over any non-breakaway portion of the installation that remains in the ground or rigidly attached to the foundation. Figure 1 illustrates the method used to measure the required 100mm maximum stub height. Breakaway support mechanisms are designed to function properly when loaded primarily in shear. Mechanisms are designed to be impacted at bumper height, typically 500mm above the ground. If impacted at a significantly higher point, the bending moment in the breakaway base may be sufficient to bind the mechanism resulting in non-activation of the breakaway device. Therefore it is critical that breakaway supports not be located in ditches, on steep slopes or in similar situations where a vehicle is likely to be partially airborne at the time of impact. Figure 1: Breakaway Support Maximum Stub Height 6.4 Assembly All brackets and fittings applicable to a modular system used shall be supplied and installed in accordance with the manufacturer's recommendations to ensure tightness throughout the life of the sign. Page 16

24 7 MAINTENANCE 7.1 Cleaning The surface of the sign face material shall be capable of having road dirt and grime readily removed from it. Signs shall be cleaned in a manner and frequency that maintains visibility of the sign at all times. Cleaning Recommendations Frequent cleaning will maintain sign faces in better condition than infrequent attempts to remove substantial accumulations of dirt. In industrial areas and on roads with high traffic volume where the dirt may be greasy and more adherent, frequent cleaning is essential. Signs should be flushed with clean water to remove loose dirt particles, and then washed with a soft brush or sponge using a non-abrasive dilute neutral cleaner. Signs should be washed from the top down and rinsed thoroughly with clean water to remove all traces of the cleaner. Tar, oil, crayon, lipstick, diesel smut and bituminous material can be removed with mild solvents, in accordance with the sign manufacturer's recommendations. Avoid screenprocessed areas. After solvent wipe, wash with neutral detergent and water, and then rinse with clean water. Strong solvents and alkaline preparations should not be used for cleaning signs. Apart from the possible effects of such materials on the hands of the workmen involved, residue left to dry and concentrate on reflective sheeting and painted surfaces can be very damaging. Transparent protective overlay films, which are designed to facilitate the cleaning, and maintenance of signfaces may be used in accordance with the sheeting manufacturer's recommendations. 7.2 Repairs Covering Signs Temporarily If it is necessary to cover the sign face temporarily following erection, use caution since some coverings may cause permanent damage to the sign face following exposure to moisture, sunlight etc. Porous cloth covers, which are folded over the sign edges and secured at the back of the sign, are recommended. Do not use tape, paper, plastic or sheet metal covers. Page 17

25 8 COMPLIANCE Signs that are manufactured, installed and maintained in accordance with the clauses contained in this Standard are deemed to comply with TNZ P/ Alternative Means of Compliance Compliance of signs or sign components with this Standard, and therefore with the Specification may be established by an independent professional opinion supported by test evidence and/or a reasoned argument based on similarity to an approved product. Matters to be covered by the opinion should include the materials of construction, sign face material, structural and impact performance, design life and wind loading. 8.2 Right of Review Transit New Zealand reserves the right to seek alternative opinions or test evidence on the compliance of any element of a sign. Where this information, or resulting conclusions, are in conflict with the submitted compliance documentation, the sign will not comply with the Specification or this Standard until the supplier has satisfied Transit New Zealand of the fitness for purpose of the sign. Page 18

26 APPENDIX A STIFFENING OF NON-DIRECTIONAL PERMANENT WARNING AND REGULATORY SIGNAGE Notes Relating to Use of Drawings This Appendix relates to Section 5.5.2, Stiffening of non-directional Permanent Warning and Regulatory Signage. The drawings provide guidance as to how to apply stiffening extrusions on four common sign shapes. Note: Small Channel = stiffening extrusion is 18.2 mm wide Medium Channel = stiffening extrusion is 24.5 mm wide Page A1

27 A) RG5 STOP SIGN B) RG6 GIVEWAY SIGN 1015mm (Medium Channel) 1200mm (Medium Channel) mm (Small Channel) 900mm (Small Channel) C) PERMANENT WARNING DIAMONDS x 1200mm (Medium Channel) 900 x 900mm (Small Channel) D) CIRCLES mm dia. (Medium Channel) mm dia. (Small Channel) 149 Page A2

28 mm (Small Channel) mm (Small Channel) x 750mm 600 x 600mm (Small Channel) (Small Channel) mm dia. 600mm dia. 400mm dia. (Small Channel) (Small Channel) (Small Channel) Page A3

29 APPENDIX B POST SELECTION CHARTS FOR SMALL SIGNS B1 Notes Relating to Use of Charts The charts in this appendix can be used for the selection of typical post sizes for small signs (sign panel area less than or equal to 4.7m 2 ) located at the roadside. The following notes apply: 1. Charts are based on open terrain (Terrain Category 2) with gentle topography (M h = 1.0). A conservative approach for signs in hilly terrain (with slopes up to 1 vertical to 5 horizontal), is to multiply the sign area by 1.35 before entering the chart to select the post sizes required. If in shadow lee zones, or areas of known channelling, multiply the sign area by 1.8 before entering the chart. For more severe topography, or a less conservative approach, specific design is required. 2. For posts in terrain category 3 the sign area may be multiplied by 0.8 before entering the chart to select the post sizes required. 3. A structure importance level of 1 has been used, with an annual probability of exceedance for ultimate limit state for wind loading of 1/ A drag force coefficient of 1.5 has been applied, (C d = 1.5). 5. The charts are for single post installations. For multiple post installations refer to Section B below. 6. Design to AS/NZS is required for signs at an elevation greater than 500m above sea level. B1.1 How to Use the Charts 1. Select the appropriate wind speed for the given sign location. The charts for the regional wind speed of 45m/s apply to Wellington and the Marlborough Sounds, (Region W). The charts for a regional wind speed of 39m/s apply to all other regions, (Regions A6 & A7). 2. Consider the local topography as outlined in Section B1 1 above and adjust sign area to be entered if necessary. 3. Select the appropriate post type, (Section B1.2 of this appendix lists the types covered by these charts). 4. For single post installations select the appropriate sign area (A) and follow the chart across to find the intercept with the required sign height (H) measured from ground level to the centre of the sign panel. The section size required is the one for the curve above this point of intersection. 5. For multiple post installations the required sign area (A) must be multiplied by (1.15/n) before entering the chart, where n is the number of posts to be used. Page B1

30 B1.2 List of Charts Included in this Appendix Post Selection Chart for Basic Wind Speed Chart No. Pole Type Wind Speed 1 Timber (Radiata No.1) 39m/s 2 Aluminium CHS (255 MPa) 39m/s 3 Steel CHS (C350) 39m/s 4 Steel RHS (C350) 39m/s 5 Timber (Radiata No.1) 45m/s 6 Aluminium CHS (255 MPa) 45m/s 7 Steel CHS (C350) 45m/s 8 Steel RHS (C350) 45m/s Page B2

31 Maximum Permissable Sign Area, A (m 2 ) Chart B1 Timber (Radiata No.1) Post Selection Chart for Regional Wind Speed of 39m/s (Region A for Average Recurrence Interval of 50 Years & Importance Level of 1 (AS/NZS 1170)) [ULS Pressure (F) =1.13kPa at <5m, Terrain Category 2] x 200mm 150 x 150mm 100 x 200mm Area = A (m2) H (m) Notes: 1. Refer to the notes at the front of this appendix. 2. Chart is based on a maximum sign eccentricity of 0.15 times the sign panel width ( i.e. a 1.5m wide sign with its centre offset a maximum of 225mm from the post centreline ). 3. The plateau on the selection curves results from shear and torsional effects on the post. 4. The chart assumes that the longest side of the post section is perpendicular to the sign face x 150mm x 100mm Height to Centre of Sign, H (m) Page B3

32 Maximum Permissable Sign Area, A (m 2 ) Aluminium CHS (255MPa) Post Selection Chart for Regional Wind Speed of 39m/s (Region A for Average Recurrence Interval of 50 Years & Importance Level of 1 (AS/NZS 1170)) [ULS Pressure (F) =1.13kPa at <5m, Terrain Category 2] Chart B mm diam CHS x 4.4mm 102mm diam CHS x 4.1mm Area = A (m2) H (m) Notes: 1. Refer to the notes at the front of this appendix. 2. Chart applies for maximum sign eccentricity of 0.75m (i.e. a 1.5m wide sign mounted on one edge). 3. The kink in the selection curves is a result of the l/20 serviceability deflection limit mm diam CHS x 3.6mm mm diam CHS x 3.1mm mm diam CHS x 2.8mm Height to Centre of Sign, H (m) Page B4

33 Maximum Permissable Sign Area, A (m 2 ) Steel CHS (C350) Post Selection Chart for Regional Wind Speed of 39m/s (Region A for Average Recurrence Interval of 50 Years & Importance Level of 1 (AS/NZS 1170)) [ULS Pressure (F) =1.13kPa at <5m, Terrain Category 2] Chart B Area = A (m2) H (m) Notes: 1. Refer to the notes at the front of this appendix. 2. Chart applies for maximum sign eccentricity of 0.75m (i.e. a 1.5m wide sign mounted on one edge) mm diam CHS x 2.0mm mm diam CHS x 2.0mm Height to Centre of Sign, H (m) Page B5

34 Maximum Permissable Sign Area, A (m 2 ) Chart B4 Steel RHS (C350) Post Selection Chart for Regional Wind Speed of 39m/s (Region A for Average Recurrence Interval of 50 Years & Importance Level of 1 (AS/NZS 1170)) [ULS Pressure (F) =1.13kPa at <5m, Terrain Category 2] 4.5 Area = A (m2) 4.0 H (m) x 50 x 3.0 RHS Height to Centre of Sign, H (m) Notes: 1. Refer to the notes at the front of this appendix. 2. Chart applies for maximum sign eccentricity of 0.75m (i.e. a 1.5m wide sign mounted on one edge). Page B6

35 Maximum Permissable Sign Area, A (m 2 ) Timber (Radiata No.1) Post Selection Chart for Regional Wind Speed of 45m/s (Region W for Average Recurrence Interval of 50 Years & Importance Level of 1 (AS/NZS 1170)) [ULS Pressure (F) =1.51kPa at <5m, Terrain Category 2] Chart B x 200mm Area = A (m2) H (m) Notes: 1. Refer to the notes at the front of this appendix. 2. Chart is based on a maximum sign eccentricity of 0.15 times the sign panel width ( i.e. a 1.5m wide sign with its centre offset a maximum of 225mm from the post centreline ). 3. The plateau on the selection curves results from shear and torsional effects on the post. 4. The chart assumes that the longest side of the post section is perpendicular to the sign face x 150mm 100 x 200mm 100 x 150mm x 100mm Height to Centre of Sign, H (m) Page B7

36 Maximum Permissable Sign Area, A (m 2 ) Aluminium CHS (255MPa) Post Selection Chart for Regional Wind Speed of 45m/s (Region W for Average Recurrence Interval of 50 Years & Importance Level of 1 (AS/NZS 1170)) [ULS Pressure (F) =1.51kPa at <5m, Terrain Category 2] Chart B mm diam CHS x 4.4mm Area = A (m2) H (m) Notes: 1. Refer to the notes at the front of this appendix. 2. Chart applies for maximum sign eccentricity of 0.75m (i.e. a 1.5m wide sign mounted on one edge) mm diam CHS x 4.1mm mm diam CHS x 3.6mm mm diam CHS x 3.1mm 60mm diam CHS x 2.8mm Height to Centre of Sign, H (m) Page B8

37 Maximum Permissable Sign Area, A (m 2 ) Steel CHS (C350) Post Selection Chart for Regional Wind Speed of 45m/s Chart B7 (Region W for Average Recurrence Interval of 50 Years & Importance Level of 1 (AS/NZS 1170)) ULS Pressure (F) =1.51kPa at <5m, Terrain Category 2] 4.5 Area = A (m2) 4.0 H (m) Notes: 1. Refer to the notes at the front of this appendix. 2. Chart applies for maximum sign eccentricity of 0.75m (i.e. a 1.5m wide sign mounted on one edge) mm diam CHS x 2.0mm mm diam CHS x 2.0mm Height to Centre of Sign, H (m) Page B9

38 Maximum Permissable Sign Area, A (m 2 ) Chart B8 Steel RHS (C350) Post Selection Chart for Regional Wind Speed of 45m/s (Region W for Average Recurrence Interval of 50 Years & Importance Level of 1 (AS/NZS 1170)) [ULS Pressure (F) =1.51kPa at <5m, Terrain Category 2] 4.5 Area = A (m2) 4.0 H (m) x 50 x 3.0 RHS Height to Centre of Sign, H (m) Notes: 1. Refer to the notes at the front of this appendix. 2. Chart applies for maximum sign eccentricity of 0.75m (i.e. a 1.5m wide sign mounted on one edge). Page B10

39 APPENDIX C FOUNDATION SELECTION TABLES FOR SMALL SIGNS C1 Notes Relating to Use of Tables The tables in this appendix give the required depth of embedment (L) for cylindrical foundations for a range of applied forces and sign heights. These tables have been derived using Broms theory. A table for shallow pad foundations has also been included for situations where underground services are present. The following notes apply: 1. Topsoil, very soft or very loose surface sediments shall not be included in the embedment depths given in the tables. 2. Soil type should be assessed from appropriate investigation. 3. Specific design is required if the groundwater level is above the base of the footing. C1.1 How to Use the Tables 1. Evaluate the soil conditions for the given sign location. Section C1.3 of this appendix gives typical properties and the appropriate foundation selection table for a range of soil types. If soil conditions are not known Table C1 may be used. 2. If a shallow pad foundation is required in areas with underground services Table 16 can be used to size the pad. 3. Calculate the force on the sign panel using Sign Area (A) x Ultimate Limit State wind pressure (F), given on the post selection charts. 4. Enter the left-hand column of the foundation selection table and select the appropriate value of F x A. 5. Follow the row across to the appropriate column for the height of the sign (measured from ground level to the centre of the sign panel). 6. Read off the required depth of embedment which is given in metres. C1.2 Typical Soil Parameters for Table Selection These parameters are based on values from J.E. Bowles, Foundation Analysis and Design, Third Edition, McGraw Hill, 1984 and NZ Geomechanics Guidelines for Field Descriptions of Soils and Rocks in Engineering Use. The foundation selection tables are generally based on soil properties at the lower bound of those indicated below. Page C1