缅甸某输电线路工程双回直线塔真型试验研究

FULL-SCALE TEST ON DOUBLE-CIRCLE TANGENT TOWER IN A TRANSMISSION LINE PROJECT IN MYANMAR

缅甸某输电线路工程是“一带一路”建设的重要组成部分。双回直线(DS)塔占输电线路工程铁塔整基的83%,最大设计风速35 m/s,无覆冰,0°转角,设计采用美国标准ASCE 10-97;塔身主材采用Q345角钢,8.8级高强螺栓连接,呼高37.0 m,全高52.8 m,单基塔质量为13.69 t。DS塔顺利通过断一相地线、断一相导线、装地线和装导线4种工况的100%设计荷载真型试验,在最大横向风超载工况下,加载到110%设计荷载约2 min后,塔腿主材和辅助材先后屈服破坏。试验表明:铁塔位移和应力测试结果满足设计变形及构件承载力要求,结构设计合理,安全可靠,节省了整体用钢量,达到了预期目标。

The transmission line project in Myanmar is an important and significant part of the Belt and Road.The DS double-circle tangent towers,which account for 83 percent of total towers in transmission line projects,has the maximum design wind of 35 m/s,no ice coating,and 0°ration angle,and design can meet the requirements of ASCE 10-97.Q345 angle steel is used for the main members and the grade 8.8 high-strength bolts are used for the connecting members.The tower’s nominal height is 37 m,total height is 52.8 m and weight is 13.69 t.The DS tower sucessfully passed the 100%design load full-scale tests of four conditions,which including a broken phase ground wire,a broken phase conductor,installing ground wire and installing conductor.Under the maximum lateral wind overload condition,the main and auxiliary members of the tower leg occurred yield failure after loading to 110%of the design load for about 2 minutes.The test results indicated that the monitoring results displacement and stress of the tower could meet the requirements of design formation and member bearing capacity respectively,in addition,the tower design which was safe and reasonable could save the total amount of steel,and meet the design expectations for the international transmission line project.