钻孔灌注桩施工对临近电力顶管隧道的影响研究

电力顶管隧道保护是岩土环境土工问题中的重要研究内容;而钻孔灌注桩为非挤土桩,一般对周边环境影响较小。根据施工实例表明在距离电力隧道3 m附近施工3枚钻孔灌注桩;导致电力隧道变形达6.97 mm。为了确保电力隧道的安全,降低钻孔灌注桩对电力隧道的影响。借助有限元分析以及常规监测手段对钻孔灌注桩施工导致电力隧道变形影响的机理展开分析。研究表明,刚灌入的混凝土所产生的附加应力对周围土体有挤压作用,这种挤压作用进而造成电力隧道结构变形、位移。当钻孔桩与电力隧道净间距控制超过5 m,可有效降低对电力隧道的影响。

Study on bored piles construction influenced on adjacent pipe-jacking tunnel of electric power

The Power pipe-jacking tunnel protection is one of the top environmental concerns in geotechnical engineering. Bored piles are not belong to compaction pile, which are generally smaller influence on surrounding environment. According to construction examples show that three bored piles caused power tunnel deformation of 6.97mm that are near power tunnel an interval of 3 metres. In order to ensure the safety of the power tunnel, reducing the influence of the bored piles on power tunnel, the influence mechanism of bored piles construction leads to power tunnel deformation was analyzed with the aid of finite element analysis and routine monitoring method. Studies have shown that the additional stress produced by just pumping concrete have squeezing effect on the surrounding soil, which lead to power tunnel structure deformation and displacement. When the spacing keep more than 5 m between bored pile and pipe-jacking tunnel, it can effectively reduce the impact on electric power tunnel.