桩板式挡土墙加固方案及技术评价

Reinforcement scheme of sheet-pile retaining walls and relevant technical evaluation

本文以某工程桩板式挡土墙工程施工过程中桩身发生倾斜需采取加固措施为例,对其失稳内在原因与力学原理进行了分析。与常规加固方案对比,采用了圈梁、腰梁、地基压密灌浆等一系列加固处理措施,运用了层次分析法,分别对不同加固措施所产生的效果进行了分析。研究表明,挖土泄压消除主动土压力,压密注浆加固土体增加被动区域土压力,混凝土弧形挡土板加固和腰梁、圈梁施工加固增加整体协调抵抗主动土压力,改用2:8灰土回填加固大幅减低主动土压力等,各个阶段均发挥了较好的作用。检测结果表明,加固工程取得了预期的效果,可为类似工程的设计、施工及安全措施提供参考,具有较好的推广价值。

Taking the reinforcement which is necessary when the inclining occurs during the engineering construction of a sheet-pile retaining wall as an example,the internal causes and the mechanic principle of the instability are analyzed. A series of reinforcement treatment measures including the ring beam,middle beam and foundation compaction grouting are used in contrast with the conventional reinforcement schemes. The analytic hierarchy process is applied to analyze the effects of different reinforcement measures. The study reveals that the desirable functions are exerted in all phases： removing active earth pressure through excavation-based decompression; increasing the earth pressure in the passive area through soil-mass reinforcement based on compaction grouting; increasing the overall coordinated resistance of active earth pressure through concrete arc breast-board reinforcement and middle beam and ring beam construction reinforcement; dramatically reducing active earth pressure by using 2： 8 lime soil for the backfill reinforcement. The testing results indicate that the reinforcement engineering has achieved its expected effect which provides the reference and the high-value popularization to the design,construction and safety measures for similar projects.