采空区塌陷对既有塔基边坡影响评价及治理

Effect of Goaf Area Collapse Impacting on an Existing Tower Foundation Slope and Treatment

山地采空区塌陷对输电线路铁塔稳定性的影响具有特殊性,除了要考虑塌陷范围内岩土体稳定性之外,还需考虑塌陷范围边缘斜坡的稳定性问题。500 k V漫昆输电线路I回137#和II回124#铁塔东南侧场地早期开挖煤矿形成的采空区塌陷,并未直接影响两塔基的稳定性,但东南侧斜坡发育较多地裂缝,经过现场勘测和定量计算分析,判定边坡的稳定性较差,在后期雨季或地震工况下边坡易发生失稳滑动,影响铁塔的安全稳定运行。由于考虑整个边坡治理投资较大,因此,为了降低治理成本,采用仅保护塔基稳定性的治理措施。

The mountain goaf collapse has special influence on transmission tower＇s stability. Both the stability of the rock mass in the collapse area and the stability of the slope at the edge of the collapse area should be taken into account. The southeastern sites of both number 137# tower（in line Ⅰ） and 124# tower（in line Ⅱ） in 500 k V ManKun transmission line are goaf collapse areas caused by early coal mine＇s excavation. These goaf collapse areas don＇t directly affect the towers＇ stability, but there are many ground fissures in southeastern slopes. The slope stability is assessed to be poor by site surveying and quantitative analysis. And the slopes are prone to slip when experiencing rainy season or earthquake condition, which could affect the safe and stable operation of the towers. Considering the large investment for the whole slope treatment, control measures just for protecting the towers＇ stability have been taken in order to reduce the cost of treatment.