膨胀土挖方渠道预支护多排微型抗滑桩设计

Design of pre-supported micro anti-sliding piles with multi-rows for excavated expansive soil canal

通过对南水北调中线工程膨胀土挖方渠道边坡滑坡特点的研究,提出了一种渠道边坡预支护多排微型抗滑桩的加固方式。该桩桩体施工与开挖同时进行,设置多排微型桩分级提供抗滑力。在施工过程中,当开挖至桩顶高程时采用静压设备将微型抗滑桩打入土体,然后再进行下一步开挖。这种支护方式已运用于南水北调中线工程南阳段膨胀土渠坡的加固施工中,监测资料显示加固后边坡位移逐步稳定,加固方式可靠、有效,为类似膨胀土挖方渠道的加固提供了参考。

Through studying the slope sliding characteristics of excavated expansive soil canal of Middle Route Project of South-to-North Water Diversion, we propose a new canal slope reinforcement measures using micro anti-slide piles that are charac-terized as pre-supported and multi-rows. The pile construction is carried out in parallel with canal excavation and multi-rows of piles are designed to provide graded anti-slide force. In the construction, when excavating to the elevation of the pile, the pile is impressed into the foundation by static pile-driving machine before the next excavation. The new supporting measure has been applied to the canal slope reinforcement of Middle Route Project of South-to-North Water Diversion, and the monitoring results show that the deformation of canal slope is in a stable state, so the reinforcement method is reliable.