No.487

Bulletin of Ministry of Construction Promulgation for the National Standard“Code for Construction and Acceptance of 750kV Overhead Transmission Line”

“Code for Construction and Acceptance of 750kV Overhead Transmission Line” has been approved as a national standard with a serial number of GB 50389—2006,and it shall come into force upon April 1,2007.Herein,Clause1.0.3,1.0.7,2.0.1(1,3),5.1.2(1),5.2.8,5.2.9(1,2,3,4),6.1.1,6.2.1,7.1.1,7.3.1,7.3.2,7.3.3,7.3.5(1),7.3.8(4),7.6.3(1) are mandatory clauses,which must be enforced strictly.

Research Institute of Standards and Norms-Ministry of Construction will organize the China Planning Press to take on publishing and distributing works of this code.

Ministry of Construction of the People's Republic of China

September 26, 2006

Bulletin of Ministry of Construction of the People's Republic of China

No.487

Bulletin of Ministry of Construction Promulgation for the National Standard“Code for Construction and Acceptance of 750kV Overhead Transmission Line”

“Code for Construction and Acceptance of 750kV Overhead Transmission Line” has been approved as a national standard with a serial number of GB 50389—2006,and it shall come into force upon April 1,2007.Herein,Clause 1.0.3, 1.0.7, 2.0.1(1,3), 5.1.2 (1), 5.2.8, 5.2.9 (1,2,3,4), 6.1.1, 6.2.1, 7.1.1, 7.3.1, 7.3.2, 7.3.3, 7.3.5 (1), 7.3.8 (4), 7.6.3 (1) are mandatory clauses,which must be enforced strictly.

Research Institute of Standards and Norms-Ministry of Construction will organize the China Planning Press to take on publishing and distributing works of this code.

Ministry of Construction of the People's Republic of China

September 26, 2006

目录

NOTICE

Bulletin of Ministry of Construction of the People's Republic of China

Preface

1 General principles

2 Verification for raw material and equipment

3 Survey

4 Earthwork

5 Foundation work

5.1 General stipulations

5.2 Cast-in-situ foundation

5.3 Bored cast-in-place pile foundation

5.4 Rock foundation

5.5 Winter construction

6 Iron tower engineering

6.1 General stipulations

6.2 Iron tower

6.3 Guy line

7 Transmission line erection engineering

7.1 General stipulations

7.2 Tension Stringing

7.3 Connection

7.4 Tightening-up

7.5 Accessories installation

7.6 Erection of optical fiber composite overhead ground wire(OPGW)

8 Grounding engineering

9 Engineering acceptance and handover

9.1 Engineering acceptance

9.2 Test of completion

9.3 Handover of engineering data

9.4 Completion handover

Appendix A Requirement for safety distance of ground and crossing

Explanation of wording in this Code

中华人民共和国建设部公告

前言

1 总则

2 原材料及器材检验

3 测量

4 土石方工程

5 基础工程

5.1 一般规定

5.2 现场浇筑基础

5.3 钻孔灌注桩基础

5.4 岩石基础

5.5 冬期施工

6 铁塔工程

6.1 一般规定

6.2 铁塔

6.3 拉线

7 架线工程

7.1 一般规定

7.2 张力放线

7.3 连接

7.4 紧线

7.5 附件安装

7.6 光纤复合架空地线（OPGW）架设

8 接地工程

9 工程验收与移交

9.1 工程验收

9.2 竣工试验

9.3 工程资料移交

9.4 竣工移交

附录A 对地及交叉跨越安全距离要求

本规范用词说明

1.0.3 750kV overhead transmission line engineering must follow approved design document and design construction drawing reviewed by relevant units.

1.0.7 Instrument, meter and gauge used for survey and inspection of overhead transmission line must adopt qualified product within valid use terms.

2.0.1 Raw material and equipment used for overhead transmission line must satisfy the following stipulations:

1 Ex-factory quality certificate of product batch shall be offered.

2Quality test information complying with current national standard shall be offered.

3 Raw material without quality test documents such as stone and sand shall be sampled and tested by qualified test organizations.Only qualified raw material is allowed to use.

4In case of any doubt for test result,re-sampled test is required by qualified test organizations,and only qualified raw material and equipment are allowed to use.

5.1.2 Employment of admixture in foundation concrete shall comply with following stipulations:

1 No chlorine salt is allowed in foundation concrete.

2When foundation concrete accepts admixtures,shall comply with stipulation of current national standard “Code for utility technical of concrete admixture” GB 50119.

5.2.8 Sample for test block shall be made during casting concrete on site and test blockcuring condition shall be same as foundation.

5.2.9 Test blocks quantity shall meet the following stipulations:

1 For corner towers, tension towers, terminal towers, transposition towers and straight-line corner towers take one set of test block every foundation unit respectively.

2 For general straight-line tower foundation, take a set of test block every 5 foundation units or less than 5 foundation units by a construction team.For single unit of concrete or continuous concrete casting volume over 100m, take one set of test block.

3 For straight line tower and guy foundation with large span design, take one set of test block every leg; If foundation concrete volume less than that in large corner tower or that of terminal tower at same project, take one set of test block every foundation unit.

4 In case material changes and mix ratio changes, make test block again.

5When other strength verification need to be done,construction teams shall decide the increased test block set numbers.

6.1.1 Iron tower erection work must be provided with full engineering technology design.During erection process, erection measure to be taken shall avoid its components to be deformed and damaged.

6.2.1 When iron tower foundation is in conformity with the following stipulations,assembly and erection of tower are allowed:

1 Foundation has passed examination of middle process inspection;

2 When decomposition of iron tower for assembly and erection, compressive strength of concrete shall reach 70%of designed strength;

3 When erection of a whole tower, compressive strength of concrete shall reach 100%of designed strength; when some effectively measures are taken to prevent foundation from level thrust in erection process of tower, compressive strength of concrete shall reach 70%of designed strength.

7.1.1 Before erection of transmission line, provide full and effective transmission lineerection construction technology document(including pay-off, tightening of line and installation of accessories).

7.3.1 Conductor or overhead cable with different metal, specification and twistingdirection is not allowed to be connected in one tensioning section.

7.3.2 When conductor or overhead ground wire is connected with hydraulic manner, onlyqualified workers with special training license are allowed to operate.With completion of connection and self-inspection, the operator shall print his name stamp on press-connect-tube.

7.3.3 Use qualified electric cable splicing sleeve and tension clamp for erection oroverhead ground wire.The holding strength after connection shall accept tensile test on testpiece before erection work.Such test pieces shall not be less than 3 groups(splicing sleeve and tensioning clamp are regarded as one group).The tested holding strength shall not be less than 95%of designed stretch-breaking force of conductor or overhead ground wire.

7.3.5 Cut and connection of conductor shall meet the following stipulations:

1 When cutting conductor aluminum strand, steel core mustn't be damaged;

2Cut edge shall be trim;

3Bad stranding,breakage of strand and shortage of strand are not allowed in connection portion of conductor and overhead ground wire;

4Strand loosening is not allowed near sleeve opening after connection.

7.3.8 Check appearance of splicing sleeve and tension pipe after pressing and shall meet the following stipulations:

1Use vernier caliper with accuracy over 0.1mm to measure size after pressing and the allowance deviation must meet current standard “Specification for hydraulic construction procedure of overhead transmission line and lighting arrester” (trial) SDJ 226；

2Burrs and damage within allowance limit shall be filed and polished with 0#sand paper；

3The bending degree shall not be over 2%,if exceeding 2%,straighten it if possible;

4 The splicing sleeve after being straightened must not show any cracks; if it fails to meet stipulation, cutting and re-jointing are necessary;

5After pressing,exposed splicing sleeve shall be coated with anti-rusting paint.

7.6.3 Construction of optical fiber composite overhead ground wire shall meet the following stipulations:

1 Line erection construction of optical fiber composite overhead ground wire shall adopt tension stringing method；

2The distance of section for pay-off of line shall be applicable to line length of reel.The pay-off line with two reels and more are not proper.

1.0.3 750kV架空送电线路工程必须按照批准的设计文件和经有关方面会审的设计施工图施工。

1.0.7 架空送电线路工程测量及检查用的仪器、仪表、量具等，必须采用合格产品并在校检有效期内使用。

2.0.1 架空送电线路工程使用的原材料及器材必须符合下列规定：

1 有该批产品出厂质量检验合格证书；

2有符合国家现行标准的各项质量检验资料；

3 对砂石等无质量检验资料的原材料应经抽样并交有资质的检验单位检验，合格后方可采用；

4对产品检验结果有怀疑时应重新抽样并经有相应资质的检验单位检验，合格后方可采用。

5.1.2 基础混凝土中掺入外加剂时应符合下列规定：

1 基础混凝土中严禁掺入氯盐；

2基础混凝土中掺入外加剂时应符合现行国家标准《混凝土外加剂应用技术规范》GB 50119的有关规定。

5.2.8 试块应在浇筑现场浇筑过程中取样制作，其养护条件应与基础基本相同。

5.2.9 试块制作数量应符合下列规定：

1 转角、耐张、终端、换拉塔及直线转角塔基础每基应取一组；

2 一般直线塔基础，同一施工队每5基或不满5基应取一组，单基或连续浇筑混凝土量超过100mm时亦应取一组；

3 按大跨越设计的直线塔基础及拉线基础，每腿应取一组，但当基础混凝土量不超过同工程中大转角或终端塔基础时，则应每基取一组；

4 当原材料变化、配合比变更时应另外制作；

5当需要做其他强度鉴定时，外加试块的组数由各工程自定。

6.1.1 铁塔组立必须有完整的施工技术设计。组立过程中，应采取不导致部件变形或损坏的措施。

6.2.1 铁塔基础符合下列规定时始可组立铁塔：

1 经中间检查验收合格；

2 分解组立铁塔时，混凝土的抗压强度应达到设计强度的70%；

3 整体立塔时，混凝土的抗压强度应达到设计强度的100%；当立塔操作采取有效防止基础承受水平推力的措施时，混凝土的抗压强度允许为设计强度的70%。

7.1.1 架线前应有完整有效的架线施工(包括放线、紧线及附件安装等)技术文件。

7.3.1 不同金属、不同规格、不同绞制方向的导线或架空地线严禁在一个耐张段内连接。

7.3.2 当导线或架空地线采用液压连接时，必须由经过专门培训并经考试合格具有操作证的技术工人担任。连接完成并自检合格后应在压接管上打上操作人员的钢印。

7.3.3 导线或架空地线必须使用合格的电力金具配套接续管及耐张线夹进行连接。连接后的握着强度在架线施工前应对试件进行拉力试验。试件不得少于3组(允许接续管与耐张线夹合为1组试件)。其试验握着强度不得小于导线或架空地线设计计算拉断力的95%。

7.3.5 导线切割及连接应符合下列规定：

1 切割导线铝股时严禁伤及钢芯；

2切口应整齐；

3导线及架空地线的连接部分不得有线股绞制不良、断股、缺股等质量问题；

4连接后管口附近不得有明显的松股现象。

7.3.8 接续管及耐张管压后应检查其外观质量，并应符合下列规定：

1使用精度不低于0.1mm的游标卡尺测量压后尺寸，其允许偏差必须符合国家现行标准《架空电力线路导线及避雷线液压施工工艺规程》(试行)SDJ 226的规定；

2飞边、毛刺及表面未超过允许的损伤应锉平并用不粗于0#细砂纸磨光；

3弯曲度不得大于2%，超过2%尚可校直时应校直；

4 校直后的接续管严禁有裂纹，达不到规定时应割断重接；

5裸露的接续钢管压后应涂防锈漆。

7.6.3 光纤复合架空地线的架线施工必须符合下列规定：

1 光纤复合架空地线的架线施工必须采用张力放线方法；

2选择放线区段长度应与线盘长度相适应。不宜两盘及以上连放。