OVERHEAD DESIGN MANUAL

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1 OVERHED DESIGN MNUL Section 2 Poles pproved by: F. Zaini ENERGEX 2015 MNUL 00302

8 Length (m) POLE DESCRIPTION MINIMUM POLE DIMETERS (mm) MX. DIMETER at GL Nominal GL Strength Rating (kn) Strength Group Strength Group Strength Group Distance from Butt (mm) (Note 1) S1 S2 S3 S1 S2 S3 Ultimate Limit State Max. Working 2m from butt t head 2m from butt t head 2m from butt t head N/ N/ N/ N/ F. ZINI REC D 20/10/2015 Note 1: llowable pole tip load under Limit State & Maximum Working Wind Conditions Note 2: Data taken from Technical Specification TS415C Vacuum Pressure Impregnated Hardwood Poles POLES WOOD POLES - CURRENT TYPE MINIMUM & MXIMUM DIMETERS ORIGINL ISSUE COPYRIGHT 2015 Energex This drawing must not be reproduced in part or whole without written permission from ENERGEX P.RELF K.GOSDEN WORD SEC SUB 2 3 SHT 4 REV

13 TIP LOD CPCITY OF NILED POLES WIND CONDITION (kn) Rebutted Poles can be assumed to be reinstated to their full original strength. Nailed or Staked Poles are often reinstated to less than their original strength, but adequate to carry the applied tip load at the time of reinstatement. Nails are currently stamped with the Ultimate Bending Moment Capacity of the pole and the year of installation. (Older nails may not be stamped in this way refer section 2.7. Use the tables below to determine Tip Load Capacity of the reinstated pole. Note: Even if the nail is of a large capacity, the tip load of the reinstated pole must NOT exceed the original tip load of the pole. Poles where the Nail is ligned with the Resultant Conductor Load Nail Resultant ULTIMTE BENDING MOMENT CPCITY OF NIL POLE LENGTH (m) Maximum Tip Load Wind Condition (kn) The above table assumes a ground line pole diameter equivalent to 3% of pole length. Sinking Depth is taken to be 0.1 x Pole Length + 0.8m. ORIGINL ISSUE REC D COPYRIGHT 2015 ENERGEX This drawing must not be reproduced in part or whole without written permission from ENERGEX F. ZINI 20/10/2015 P. RELF K. GOSDEN SECT SUB SHT REV WORD POLES REINSTTED (NILED) WOOD POLES CURRENT TYPES

14 Poles where the Nail is NOT ligned with the Resultant Conductor Loads Nail Resultant ULTIMTE BENDING MOMENT CPCITY OF NIL POLE LENGTH (m) Maximum Tip Load Wind Condition (kn) The above table assumes a ground line pole diameter equivalent to 3% of pole length. Sinking Depth is taken to be 0.1 x Pole Length + 0.8m. ORIGINL ISSUE REC D COPYRIGHT 2015 ENERGEX This drawing must not be reproduced in part or whole without written permission from ENERGEX F. ZINI 20/10/2015 P. RELF K. GOSDEN SECT SUB SHT REV WORD POLES REINSTTED (NILED) WOOD POLES CURRENT TYPES

16 BENDING MOMENT CPCITY OF WOOD POLES NOTES: 1. ll Bending Moment values are in kn.m. 2. Dia (mm) is typically ground line diameter but may be applied to any part of the pole. 3. The following Modulus of Rupture values have been used in accordance with S S1: 100Pa, S2: 80MPa, S3: 65MPa. 4. To convert from Bending Moment to Tip Load Capacity in kilo-newtons, divide by height in metres. For wind condition, de-rate by self-windage of pole: i.e. height (m) x width (m) x 1.3 x To obtain Energex allowable No Wind bending moments, multiply the No Wind value by Refer section 2-12 for more information. Diameter (mm) Ult S1 S2 S3 No Wind (5) Wind Ult No Wind (5) Wind Ult No Wind (5) Wind REC D F. ZINI 20/10/2015 POLES BENDING MOMENT CPCITY OF TIMBER POLES ORIGINL ISSUE COPYRIGHT 2015 Energex This drawing must not be reproduced in part or whole without written permission from ENERGEX P. RELF K.GOSDEN WORD SEC SUB 2 8 SHT 1 REV

17 NOTES: 1. ll Bending Moment values are in kn.m. 2. Dia (mm) is typically ground line diameter but may be applied to any part of the pole. 3. The following Modulus of Rupture values have been used in accordance with S S1: 100Pa, S2: 80MPa, S3: 65MPa. 4. To convert from Bending Moment to Tip Load Capacity in kilo-newtons, divide by height in metres. For wind condition, de-rate by self-windage of pole: i.e. height (m) x width (m) x 1.3 x To obtain Energex allowable No Wind bending moments, multiply the No Wind value by Refer section 2-12 for more information. Diameter (mm) Ult S1 S2 S3 No Wind (5) Wind Ult No Wind (5) Wind Ult No Wind (5) Wind REC D F. ZINI 20/10/2015 POLES BENDING MOMENT CPCITY OF TIMBER POLES ORIGINL ISSUE COPYRIGHT 2015 Energex This drawing must not be reproduced in part or whole without written permission from ENERGEX P. RELF K.GOSDEN WORD SEC SUB 2 8 SHT 2 REV

18 1. POLE INSPECTION FOR IN-SERVICE POLES Whenever the tip load of an in-service pole is increased by more than 1kN (No Wind condition), an assessment of the residual strength of the pole is required. Poles that are less than 10 years old, or that have been reinstated (ie nailed or rebutted) within the last 10 years, shall be exempt from this procedure. The designer shall complete Section 1 of Form 1271 Pole Inspection for ltered Tip Loads supplying the pole site ID and address. This should be forwarded to the Network Maintenance Contract Department. The Contract Officer shall arrange for a pole inspector under the current contract to inspect the pole and obtain the necessary field measurements for wood poles ground line diameter, height and dimensions of any internal hollows completing Section 2 of the form. The form is returned to the designer. For wood poles, the designer should then calculate a revised pole tip load rating using the measurements provided and the PoleStrength program within the mains design application package. Only the Limit State (LST) and Everyday (EDT) values are to be used to determine the remaining design strength of the pole. This strength is to be compared with the proposed LST tip load to determine the suitability of the existing pole. External designers have the option of liaising directly with a rated Pole Inspector to obtain the required measurements. For wood poles without any internal hollows, the table in Section 2.8 Bending Moment Capacity Of Timber Poles may be used in lieu of the PoleStrength program. Ensure any external decay is taken into account when determining diameter of pole For reinstated poles that are assessed as sound by the pole inspector, the designer shall compare the strength of the reinforcing system with the proposed tip load (refer Page 2-6 and Maintenance Instruction MI-069). 2. POLE PEGGING Poles and stays shall be pegged at the centre of the proposed position. Only ORNGE fluorescent paint (Stock Code 14010) will be used for temporary marking of pole and stay positions and pegs. Refer S 1345 for temporary marking of electrical services in road reserves Check for services clashes DBYD (phone 1100, fax ). 3. POLE LIGNMENTS Poles located within road reserves shall be installed on an alignment approved by the authority controlling the roadway generally the Department of Transport and Main roads or the local authority (council). Standard pole alignments for authorities within the ENERGEX franchise area are tabulated below. Note that certain authorities reference the alignment to the real property boundary, others behind the face of the kerb (BFK) or behind the kerb invert (BKI). Note that local authorities may have additional restrictions on pole placement, eg clearances from walking paths and bike paths. Restrictions concerning streetlight pole placement are also found in S/NZS Road Lighting. s a general guideline, ensure that there is at least 0.7m between the outside of the pole and the kerb to minimise damage from vehicle ORIGINL ISSUE COPYRIGHT 2015 ENERGEX This drawing must not be reproduced in part or whole without written permission from ENERGEX REC D F. ZINI 20/10/2015 P. RELF K. GOSDEN WORD POLES POLE INSPECTION FOR IN-SERVICE POLES & POLE LIGNMENTS SEC SUB 2 9 SHT 1 REV

19 4. STNDRD POLE ND UNDERGROUND LIGNMENTS LOCL UTHORITY POLE LIGNMENT U/G LIGNMENT SITUTION DRWING REF. COMMENTS NORTH SUNSHINE COST REGIONL COUNCIL Formerly: 0-0.9m from RP lign SEQ STD Electrical 3.0m centre from RP lign For all footpath widths Caloundra City Council (with Gas) conditions pdf Formerly: Maroochydore City Council 3.0m centre from RP lign 0-0.9m from RP lign For all footpath widths Formerly: Noosa Shire Council 3.0m centre from RP lign 0-0.9m from RP lign For all footpath widths GYMPIE REGIONL COUNCIL Council considering pole Formerly: m from RP alignment 1.0m behind 3.0m centre from RP lign R-08 Cooloola Shire Council lign kerb for footpaths exceeding 4.0m wide MORETON BY REGIONL COUNCIL Formerly: 0-1.0m from RP lign 3.2m centre from RP lign Caboolture Shire Council (with Gas) 4/01-64 Formerly: For standard footpath 4.0m 3.3m centre from RP lign 0-0.9m from RP lign Redcliffe City Council wide S m centre from RP lign 0-0.9m from RP lign For footpaths 3.5m wide Formerly: Pine Rivers Shire Council 0.45m from face of kerb 0-0.9m from RP lign 2.75m centre from RP lign For footpaths exceeding 3.5m wide For footpaths without kerbing Unnumbered sketch ORIGINL ISSUE COPYRIGHT 2015 ENERGEX This drawing must not be reproduced in part or whole without written permission from ENERGEX REC D F. ZINI 20/10/2015 P. RELF K. GOSDEN WORD POLES POLE INSPECTION FOR IN-SERVICE POLES & POLE LIGNMENTS SEC SUB 2 9 SHT 2 REV

20 LOCL UTHORITY POLE LIGNMENT U/G LIGNMENT SITUTION DRWING REF. COMMENTS BRISBNE 3.25m centre from RP lign Unnumbered BCC. Licensing For footpaths 3.66m wide to (was 3.43m to road face of m from RP lign drawing pre 1973 Compliance Officer, kerb face installed pre 1973 pole) and post 1973 ph For footpaths3.75m wide to Dan Maher, 2.9m centre from RP lign m from RP lign kerb face installed after W106/1E Road and Traffic Design. High side** 1973 Ph For footpaths3.75m wide to 2.74m centre from RP lign BRISBNE CITY m from RP lign kerb face installed after Low side** COUNCIL 1973 W106/1E 1.75m centre from RP lign m from RP lign For footpaths 2.44m wide 0.3m from back of kerb to For footpath width pole face exceeding 4.0m New Subdivisions 2.95m centre from RP lign 0.8m centre behind face of kerb 0-0.9m from RP lign For 3.75m standard width footpath. For footpaths exceeding 4.75m wide WS10-1,WS m centre from RP lign For 4.25m standard width High side 0-0.9m from RP lign footpath 3.27m centre from RP lign WS10-2, Fig B8.4 Low side (1) and (2) 0.8m centre behind face of For footpath exceeding kerb 5.25m ORIGINL ISSUE COPYRIGHT 2015 ENERGEX This drawing must not be reproduced in part or whole without written permission from ENERGEX REC D F. ZINI 20/10/2015 P. RELF K. GOSDEN WORD POLES POLE INSPECTION FOR IN-SERVICE POLES & POLE LIGNMENTS SEC SUB 2 9 SHT 3 REV

21 LOCL UTHORITY POLE LIGNMENT U/G LIGNMENT SITUTION DRWING REF. COMMENTS WESTERN LOCKYER VLLEY REGIONL COUNCIL Use existing alignment in Formerly: 3.05m centre from RP lign 0-1.2m from RP lign For footpaths 4.0m wide EROC-19, established areas if Gatton Shire Council 5.0m centre from RP lign (with Gas) For footpaths 6.0m wide unnumbered plan alignment is non standard Formerly: m from RP lign For footpaths 4.0m min 3.2m centre from RP lign Laidley Shire Council (with Gas) wide LSC-04 SOMERSET REGIONL COUNCIL Formerly: Esk & Kilcoy Shire Council IPSWICH CITY COUNCIL 3.0m centre from RP lign 0-0.9m from RP lign 3.2m centre from RP lign in Ipswich City council area 3.4m centre from RP lign in ex-moreton Shire area 0-0.9m from RP lign 0-0.9m from RP lign 2.95m centre from RP lign m from RP lign Existing established locations Existing established locations For new subdivisions with footpaths 3.75m wide STD.R010 & STD.R011 Use existing alignment in established areas if alignment is non standard Use existing alignment in established areas if alignment is non standard ORIGINL ISSUE COPYRIGHT 2015 ENERGEX This drawing must not be reproduced in part or whole without written permission from ENERGEX REC D F. ZINI 20/10/2015 P. RELF K. GOSDEN WORD POLES POLE INSPECTION FOR IN-SERVICE POLES & POLE LIGNMENTS SEC SUB 2 9 SHT 4 REV

22 LOCL UTHORITY POLE LIGNMENT U/G LIGNMENT SITUTION DRWING REF. COMMENTS SOUTHERN BEUDESERT REGIONL COUNCIL For footpaths 4.0m min Formerly: 0-1.2m from RP lign 3.05m centre from RP lign wide Boonah Shire Council (with Sewer) Formerly: Beaudesert Shire Council 3.05m centre from RP lign 0-1.2m from RP lign (with Gas) For footpaths 4.5m wide and RURL areas without kerbs , REDLND CITY COUNCIL 2.95m centre from RP lign 0-0.9m from RP lign For all footpath widths 1038 LOGN CITY COUNCIL 3.075m centre from RP lign m from RP lign For footpaths min 3.5m wide , , GOLD COST CITY COUNCIL 0.7m from face of kerb 0-0.9m from RP lign For footpaths m wide m centre from RP lign 0-0.9m from RP lign For footpaths in RURL areas ORIGINL ISSUE COPYRIGHT 2015 ENERGEX This drawing must not be reproduced in part or whole without written permission from ENERGEX REC D F. ZINI 20/10/2015 P. RELF K. GOSDEN WORD POLES POLE INSPECTION FOR IN-SERVICE POLES & POLE LIGNMENTS SEC SUB 2 9 SHT 5 REV

25 PROBLEM FIND THE TIP LOD FOR THE POLE SHOWN BELOW. Side View No Wind Condition 10.5m (GL) 3 x MRS (11 kv) T m (GL) 4 x MOON (LV) T m Refer Mechanical Loads (Section 6) - No Wind, C. For a 20 deviation: 11kV T110 MRS : 0.90 kn per Conductor x kn LV T220 MOON : 0.73 kn per Conductor x kn Since the LV is attached below the tip of the pole, we reduce its load in proportion to its height. LV resolved to tip 2.92 x 8.0 = 2.92 x = 2.23 kn 10.5 Therefore the total tip load is: 11 kv : 2.70 kn + LV resolved to tip : 2.23 kn Resultant Force Plan View Tip Height TOTL TIP LOD 4.93 kn No Wind Condition 20 ttachment Height 105 m Wind Condition Refer Mechanical Loads (Section 6) Wind, C. Note that both the span lengths of 90m and 105m are best approximated the Medium Span Length for T110. For a 20 deviation: 11kV T110M MRS : 3.86 kn per Conductor x kn LV T220 MOON : 4.19 kn per Conductor x kn Since the LV is attached below the tip of the pole, we reduce its load in proportion to its height. LV resolved to tip x 8.0 = x = kn 10.5 Therefore the total tip load is: 11 kv : kn + LV resolved to tip : kn TOTL TIP LOD kn Wind Condition The No Wind and Wind results may be compared with the tip load ratings for 12.5m poles to determine pole size and whether staying is required. Notes: ttachment Height Tip Height Only conductor loads need be considered. There is no need to include pole wind load, since this is accounted for in the pole strength rating. ORIGINL ISSUE COPYRIGHT 2015 ENERGEX This drawing must not be reproduced in part or whole without written permission from ENERGEX REC D F. ZINI 20/10/2015 P. RELF K. GOSDEN WORD POLES POLE INSPECTION FOR IN-SERVICE POLES & POLE LIGNMENTS SEC SUB 2 11 SHT 2 REV

26 ENGINEERING BCKGROUND 1. POLE STRENGTH When calculating wood pole strengths from first principles using the methods in ppendix F of S/NZS7000:2010, the following factors have been selected for Energex Poles: Factor No Wind (EDT) Wind (LST) k 1 -Duration of Load Factor k d -Degradation Factor Capacity Factor Note these values are for reference only and designers are not required to use these for designs done in accordance to this manual. For a more in depth understanding of pole strength calculations, please refer to S/NZS7000. basic description of the method used follows The tip load capacity of a solid, round, wood pole planted in firm ground can be assumed to be: F T = f D 3 gl / 32 h where: F T is tip load capacity of the pole (kn) f is the ultimate bending stress, or modulus of rupture of the timber (kpa, or kn/m 2 ) D gl is ground line diameter of the pole (m) is the component strength factor h is pole height above ground (m). Strength Group Modulus of Rupture (kpa) S1 100,000 (103,000) S2 80,000 (86,000) S3 65,000 (73,000) Values shown are from S & are repeated in S/NZS7000. Values in parentheses taken from S/NZS 2878:2000 Component Strength Factor ( ) Pole Type New Poles No Wind * Wind Wood Concrete Note that only the Wind Condition needs to be considered for concrete poles. * For the No Wind condition, F T will also need to be multiplied by This will provide an equivalent strength factor comparable to the previous working stress design methods used in Energex. For the wind condition, the result, F T, should have the wind load on the pole itself, F P, deducted. The self wind loading of the pole, resolved to its tip, can be assumed to be: F P = 0.5 h D gl P wp where: is tip load due to wind on pole and fittings (kn) F p P wp Uncontrolled document when printed is design wind pressure (kpa), kpa 0.5 is included since the centre of pressure is midway up the pole. Note that the taper of the pole can be ignored, since it is offset by the constructions/fittings at the pole top. Refer S/NZS 7000:2010 for further information. F. ZINI 20/10/2015 POLES ENGINEERING BCKGROUND REC D ORIGINL ISSUE COPYRIGHT 2015 ENERGEX This drawing must not be reproduced in part or whole without written permission from ENERGEX P. RELF K. GOSDEN WORD SEC SUB 2 12 SHT 1 REV

27 Note: Bending Moment is the product of load (kn) and distance (m) from the pivot point to the point at which the force is applied. When determining allowable conductor loads, remember to allow for the wind load on the pole itself F h For the Wind Condition, we must deduct the wind load on the pole itself: Pole Wind Load = 0.5 x Wind Pressure x height x GL diameter = 0.5 x x 9 x 0.22 = 1.29 kn Thus Wind Condition tip load capacity is revised to: Uncontrolled document when printed Example: = 5.40 kn. pole of species GB has a ground-line diameter of 220mm. The pole is 9m high (above ground). What is its tip load capacity? GB is strength group S2. Looking at the table in Section 2.8, we observe that for a strength group S2 and diameter 220mm, the maximum bending moment is: No Wind: kn.m Wind: kn.m The No Wind bending moment value now needs to be multiplied by the 0.57 factor: No Wind: x 0.57 = 19.07kN.m Dividing by the pole height of 9m, we can obtain pole tip load capacities: No Wind: 2.12 kn Wind: 6.69 kn F. ZINI 20/10/2015 POLES ENGINEERING BCKGROUND REC D ORIGINL ISSUE COPYRIGHT 2015 ENERGEX This drawing must not be reproduced in part or whole without written permission from ENERGEX P. RELF K. GOSDEN WORD SEC SUB 2 12 SHT 2 REV

28 2. NILED POLE STRENGTH To determine pole tip load capacity under wind conditions (1300Pa) from the value of ultimate strength for a nail, use the following formula: F T = M U / h - F P = 0.72 M U / h h D gl where: F T is tip load capacity of the pole (kn) M U is the ultimate bending moment capacity of the pole nail h is the height of the pole above ground (m) F p is tip load due to wind on pole and fittings (kn) D gl is ground line diameter of the pole (m) is component strength factor 3. FOUNDTIONS Foundation strengths are matched to pole strengths rather than the applied tip load. There were 2 methods used to derive these values, which are both detailed in the document ES C(b)1:1991: 1) Section 7.1: Embedment depth = 0.6m +1/10 of Pole length 2) ppendix C: F T = k D gl J 3 / 12 (h J) where: F T is tip load capacity of the pole (kn) k is the passive soil reaction per unit depth (kpa/m) D gl is ground line diameter of the pole (m) J is the sinking depth of the pole (m) h is pole height above ground (m) The depth used in this manual is the greater of the 2 values calculated using these methods. Imported foundation materials such as concrete effectively increase the bearing area of the pole against the natural ground. lso refer to S/NZS 7000:2010 and Handbook HB331 Section 9.1. The foundation depths shown on Pages & are based on values used in the previous versions of the OHDM. These have been successfully used for a long period of time and have provided good service performance. F. ZINI 20/10/2015 POLES ENGINEERING BCKGROUND REC D ORIGINL ISSUE COPYRIGHT 2015 ENERGEX This drawing must not be reproduced in part or whole without written permission from ENERGEX P. RELF K. GOSDEN WORD SEC SUB 2 12 SHT 3 REV

Works on Local Government Controlled Roads. & Traffic Control Permit No

Works on Local Government Controlled Roads & Traffic Control Permit No. 171219-000220 Pursuant to Local Government Act 2009 (Section 75) This permit is valid for the following purpose(s) at the locations,