强夯法处理碎石回填地基施工参数现场试验研究

摘要

In this paper,a series of dynamic compaction tests,with different energy levels,were carried out on a typical gravel backfill foundation.The compression deformation characteristics and the effective reinforcement depth of the soil were detected and analyzed comprehensively.The construction parameters of dynamic compaction of the gravel foundation were put forward.It is found out that,whatever the ram energy is,the opti-mal number of the hit is 1 3~1 6 times and the effective reinforcement depth of 3 000 kN energy level is about 4.2 m.Furthermore,based on observation and testing projects data of the density detection,load test,rebound test, ground subsidence,it is proved rational and applicable to use dynamic compact to reinforce gravel backfill foun-dation.The obtained parameters can provide reference for the design,construction and monitoring of the dynamic compaction of the same type.%通过对典型碎石回填地基开展一系列不同能级的强夯试验，对夯坑及其周围土体的压缩变形特性和强夯有效加固深度进行全面检测与分析，提出强夯加固碎石地基的施工参数。研究结果表明：无论单击夯击能如何，最佳夯击次数均为13～16次；在最佳夯击次数条件下，3000 kN·m能级强夯有效加固深度约为4．2 m。进一步对54．84万 m2的高填方强夯地基开展密度检测、载荷试验、回弹试验、地基沉降观测等监测和检测项目，验证了本次强夯施工的合理性和适用性。所得参数可以为同类工况的强夯设计、施工及监测提供参考。