深基坑桩锚与钢支撑联合支护监测分析

Monitoring Analysis on Deep Foundation Pit of Pile-Bolt and Steel Support Structure

为了研究桩锚加钢支撑联合支护深基坑的支护效果,采用综合监测的方法对支护结构的支护桩水平位移、桩身内力、桩侧土压力及孔隙水压力进行了实时监测研究。监测结果表明:支护桩水平位移桩顶大、桩底小,总体上呈线性变化,第二、三道锚杆施工过程是支护桩水平位移变化最大的时间段;支护桩主动侧和被动侧钢筋均受压应力,第二道锚杆锁定后,支护桩外侧钢筋应力不断增大,内侧钢筋应力呈减小趋势,说明及时锁定锚杆可以有效地改善桩身内力状况;支护桩桩侧土压力分布近似呈三角形,第二道锚杆施工完后,土压力开始逐渐增大;孔隙水压力主要受大气降雨及基坑施工排水的影响。

To study the effect of the pile-bolt and steel support structure used on deep foundation pit, integrated monitoring method to real-time monitoring to study the level distance of retaining piles, the internal force of piles, soil pressure of piles sides and pore water pressure has been used in the paper. The monitoring results show thatthe maximum of the level distance of retaining piles is at the top of pile, the minimum is at the bottom of pile, the changes is line overall. The time of the maximum level distance of retaining piles is during the construction of the second and the three row bolts. The stress of the active and the passive side of retaining piles is eompressive stress, After the construction of the second row bolts, the outside stress of retaining piles is growing, the medial stress of retaining piles is decreasing, which indicates that timely locking bolt can improve the stress of the retaining piles effectively. The earth side pressure of the retaining piles was similar to triangle. After the construction of the second row bolts, the earth side pressure of retaining piles is growing. The pore water pressure is affected by the rainfall and the drainage of pit construction.