架空输气管道上方岩体崩塌灾害稳定性评估及治理

Stability evaluation and treatment of overhanging rock body collapse disaster to aboveground gas pipeline

架空管道上方存在危岩体时,管道若直接遭受落石冲击,其危害将极其严重。以某架空管道上方岩体崩塌灾害治理为例,根据崩塌体基本特征,从地形地貌、软硬相间岩性组合差异风化、地下水条件等方面阐明了崩塌灾害的成因和变形破坏机理,并对岩体稳定性进行了计算评价。结果表明,崩塌体破坏形式为随机块体崩落及整体“拉裂→倾倒→崩溃”式破坏两种,其可能造成架空管道防腐层或管体的刮痕压坑、管道受力变形,甚至管道破裂、爆炸等毁灭性破坏。基于上述分析,给出了“危岩体清理+锚杆挂网喷浆防护”的治理措施。同时针对架空管道及管道入地段在施工期间可能遭受落石危害的特殊性,通过分析计算,从施工工法工序调整、埋地管道防护、架空管道防护等方面制定了对应的安全防护措施,保障了治理期间的管道安全。

When there is dangerous rock body overhanging an aboveground pipeline and if the pipeline suffers directly from rockfall impact,the harm will be extremely serious.Taking the treatment of rock body collapse disaster suffered by an aboveground pipeline as an example,according to the basic characteristics of the collapse body,the causes and deformation damage mechanism of the collapse disaster were clarified from the aspects of topography,differential weathering of combined layers of soft and hard rocks as well as ground water conditions,the rock stability was calculated and evaluated.The results show that the rock body collapse has two kinds of destruction forms,i.e.the random rock body collapse and the integral collapse with the process of"cracking→dumping→collapse",which may cause scratches,pressure pits of pipeline anticorrosion coating and pipeline body,pipeline deformation,even the devastating damage of pipeline rupture and explosion.Based on the above analysis,the treatment measures of"cleanup of dangerous rock bodies+protection with hanging nets on anchor rods and grouting"were given.At the same time,in view of the particularity of the the aboveground pipeline and the pipeline section entering soil that may suffer rockfall hazard during construction,the calculation and analysis were put forward,then the corresponding safety protection measures were formulated from the aspects of construction process adjustment,buried pipeline protection,aboveground pipeline protection and others to ensure the pipeline safety.