Specification and Guide to Poles and Lazerlogs March 2011
Introduction Croft Pole Distributors Ltd has been a producer of poles, posts, lazerlogs and timber since 1987. The company specializes in the production of pine products for harsh environment or severe outdoor service with treatment to Hazard Classes H4, H5 and H6.
1 Scope: This specification details requirements for treated timber posts and poles for medium hazard in ground service. The design of the pole shall generally take into account, as appropriate, the limit states of stability strength, serviceability, durability and other requirements of AN/NZS 4676:2000. 2 Design Environment: Climatic design parameter Climate Climatic design value Temperate Coastal- saline Ambient Air Temperatures Normal range -5 to 35 C Mean Annual 15.5 C Rainfall average 1200mm Relative Humidity Up to 100% Altitude 1-1000m 3 Quality: General requirements: Each pole shall be sound, reasonably straight, uniformly tapered and free from excessive flare at the butt. 4 Timber Species and Source The species used shall be High Density Pinus Radiata sourced exclusively from Northland forests. Latitude 35 to 36 South. Crofts approach to foundation pile production starts with a long term supply of high density radiata pine. Crofts currently has in place supply agreements with logging contractors for low altitude, northern region and coastally grown pine. Tree age and knot size specification ensure that the stringent quality parameters to meet the New Zealand
standards for foundation pile and anchor pile strength requirements are met. Wood is currently sourced from forests that are certified by the Forest Stewardship Council as sustainable forests. 5 Timber Grade Excluded defects Poles shall be visually inspected for the following defects. Visible defects shall not exceed the defined limits and any pole that exhibits defects in a position or to such extent that the structural integrity or service life of the pole or post is reduced, shall be rejected - decay - checks- the top and side surfaces shall be free from injurious checks and splits - Insect damage damage by insects or larvae including excessive superficial damage by bark boring insects - Transverse fractures - Shakes - Knots- large decayed or loose knots - End splits 6 Peeling Posts and Poles All outer bark and at least 90% of the cambium layer shall be removed, with no piece longer than 75mm or wider than 12mm remaining. The cutting heads shall follow the natural contours and irregularities of the pole and remove a minimum of wood so as to retain full strength. Only the minimum amount of sapwood shall be removed during peeling operations.
7 Rounding Lazerlogs Lazerlogs shall be machined to a uniform diameter using feedstock with small end diameter within 25 mm of the final machined size. Cylindrical Lazerlogs are produced up to 200mm diameter. 8 Steam Seasoning Before chemical impregnation, each post shall be seasoned by low pressure steaming. 9 Physical Preparation Where the customer has specified incising, boring, chamfering, surfacing spitting, pointing etc, this shall be done before treatment with preservative. The finished surface shall be reasonably smooth and free from loose splinters and not damaged from chainsaw notches or axe cuts. 10 Preservative Treatment The poles shall be treated with Chrome Copper Arsenate Oxide (CCA Oxide) to a hazard class either H4 or to H5 hazard class complying with NZS3640:2003 using an alternating pressure method cycle. The preservative shall be approved under the Hazardous Substances and New Organisms Act 1996.
Penetration of the preservative shall be to the full depth of the sapwood present. Insufficient penetration Full sapwood penetration achieved by Crofts APM treatment Core sampling and boring in determination of the penetration of the preservative process shall be in accordance with the quality standards required by NZS 3640:2003 and AS2209-1994. 11 Branding/Tags Each pole shall be branded or tagged with a code providing the following information. Treatment plant registration number (409) Preservative code number CCA (01) Hazard class (H5 or H4) Woodmark Registration Symbol
12 Size and Strength Poles will be specified by nominal length, and minimum small end diameter. Lazerlogs shall be specified nominal length, and wet state machined diameter. The design strength in bending (fb) for the poles and posts shall be 38MPa. ( 52 MPa Caracteristic per NZS 3603:1993) The design strength in bending (fb) for the lazerlogs shall be not more than 32MPa. 13 Proof Testing for Wood Supply Quality Assurance Proof testing is used on an annual basis to confirm the calculated strength of the poles and as a quality check of the actual timber characteristic stresses. A small sample set of poles, posts or lazerlogs shall be randomly selected and stress tested. The pole shall be orientated for proof testing with its axis horizontal and the load applied at right angles. Poles shall withstand the applied loads without signs of distress. Loads shall be applied at the ground line. Proof load is calculated from
P g = P s (L-a-b) kn (G-a) Where Ps (small end) proof load is calculated from P s = k f b D 3 x 10-6 32(L-G-b) kn k f b D = 0.9 for poles graded to AS2209-1994 = product adjustment factors from NZS4676:2000 for peeling & steaming (0.75 & 0.85) = characteristic bending strength (MPa) = Minimum diameter at ground line Test equipment is in accordance with NZS 3605:2001 appendix C Crofts three-point-bending test rig Hydraulically loaded with Loadrite Electronic scale 150mm X 2.7m SEDPost GL Load 2200kg 175mm X 2.7m SEDPost GL Load 3300kg 13 Export Phytosanitary Certification : Crofts poles currently holds Biosecurity New Zealand approval for the phytosanitary treatment and inspection of product for export. These procedures are accredited and audited by an authorised Independent Verification Agency.
14 Standard sizes produced H5 CONSTRUCTION POLES - H5 SED CROFT POLES Diameter 125mm 150mm 175mm 200mm 225mm 250mm 275mm 300mm 325mm 350mm 375mm 400mm Length 0.9m stock stock stock stock 1.2m stock stock stock stock stock 1.5m stock stock stock stock stock 1.8m stock stock stock stock stock 2.1m stock stock stock stock stock stock 2.4m stock stock stock stock stock stock 2.7m stock stock stock stock stock stock stock 3.0m stock stock stock stock stock stock stock stock stock 3.6m spec stock stock stock stock stock stock stock stock stock 4.2m spec stock stock stock stock stock stock stock stock stock 4.8m spec stock stock stock stock stock stock stock stock stock spec spec 5.4m spec stock stock stock stock stock stock stock stock stock spec spec 6.0m spec stock stock stock stock stock stock stock stock stock spec spec 7.0m spec stock stock stock stock stock stock stock stock stock spec spec 8.0m spec stock stock stock stock stock stock stock stock stock spec spec 9.0m spec spec stock stock stock stock stock spec spec spec spec 10.0m spec spec stock stock stock stock stock spec spec spec spec 11.0m spec stock stock stock stock stock spec spec spec spec 12.0m spec spec stock stock stock stock spec spec spec spec 13.0m spec spec spec spec spec spec spec spec spec 14.0m spec spec spec spec spec spec spec spec spec 15.0m spec spec spec spec spec spec spec H5 LAZERLOGS - Sizes Available Diameter 90mm 100mm 125mm 150mm 175mm 200mm Length 1.2m spec spec spec spec 1.5m spec spec spec spec spec spec 1.8m spec spec std std std std 2.1m spec std std std std std 2.4m spec std std std std std 2.7m spec std std std std std 3.0m spec spec std std std std 3.6m spec spec std std std std 4.2m spec spec spec std std std 4.8m spec spec std std std 5.4m spec spec spec spec 6.0m spec spec spec 7.0m spec spec spec 8.0m spec spec spec
15 Technical Resources Key Managers and Technical Staff Darrell Croft Managing Director 36 years forest industry experience including forest management, logging, sawmilling, preservative treatment and sales. Sawmill operation since 1980. 3rd generation sawmiller in Northland. David Watson- General Manager Bachelor of Engineering and Post Graduate Diploma in Business Administration. 24 years industrial processing experience with 10 years of Pulp and Paper technology design and management. Felice Croft- Production Manager /Quality Control 8 years experience in timber processing. National qualification in timber testing and grading and independently verified by Graderight NZ. Registrations and Certifications Current qualifications held by Crofts for the production of certified timber products includes: Registered as an Approved Foundation Pile Producer (Plant No3) Timber Preservation Council registration for CCA treatment of timber Woodmark- registration and certification Graderight Verified for visual grading and mechanical stress testing of timber Applicable New Zealand Standards NZS3605:2001 Timber Piles and Poles for Use in Building NZS 3640: 2003 Chemical Preservation of Round and Sawn Timber NZS 3631:1988 Timber Grading Rules NZS 3603:1993 Timber Structures Standard NZS 3602: 1995 Timber and Wood Based Products For Use In Building
Appendix Proof testing Calculation Sheet Overall length F19 Cell F24 Load at groundline K24 Small end diameter F21 Load at top end support F25 CellF22 Cell F23 Calculation of deflection at the groundline for a pole loaded at the groundline and supported at the tip and the base Input data Butt end diameter = 196.6 mm Overall pole length (m) = 2.7 Test span = 2.5 mm Assumed taper (mm/m) = 8 Diameter at top end support = 175.8 mm Small end diameter (mm) = 175 Diameter at groundline = 191 mm Butt end to support distance (m) = 0.1 Groundline to top support = 1.9 m Top end to support distance (m) = 0.1 Butt end support to groundline = 0.6 m Butt to groundline point of load application (m) = 0.7 Load at groundline = 51.04 kn 5208 kgf Load at top end support (kn) = 12.25 Bending stress at load point = 34.02 MPa Given the load, pole size and MoE: Note; Max stress for high density poles = 37.6 MPa Expected MoE (GPa) from NZS3603 = 12.1 Deflection at groundline (mm) = 12 Smallest SED recommended for given loads = 169 mm Given the load, pole size and deflection at the ground line: Observed deflection at ram at groundline (mm) 70 MoE (GPa) = 2.05 Instructions: 1. Fill in the red values in the input data box 2. If you want to know the deflection at the groundline given the MoE, put in the value in cell F17. Your answer is in cell F18 load held 15 seconds 3. If you want to know the MoE given an observed deflection under load, fill in the value in cell F21. Your answer is in cell F22 Test 1 Test 2 Test 3 Test 4 Test 5 calc fb Mpa 38 test point proof load proof load Load appllied Load appllied Load appllied Load appllied Load appllied fracture load proof load 32.95 kn SED m from lg end kn load kg pass pass pass pass pass ground line 100/2.7 0.7 7.38 753 for situation above 125/2.7 0.7 13.26 1353 1350 2250 150/2.7 0.7 21.63 2207 2200 3000 4000 175/2.7 0.7 32.95 3362 3800 5100 fb Mpa 32 27.75 kn LL 100/2.7 2.4 3.98 406 400 500 600 700 800 LL failure Mpa 37.16 125/2.7 2.4 7.78 794 900 1000 150/2.7 2.4 13.4 1367 1422 1500 Sed1 failure Mpa 37.3 175/2.7 2.4 21.34 2178 2320 2600 Sed2 failure Mpa 40.6 Sed3 okmpa 34.02