牙四公路路基水泥搅拌桩承载力影响因素研究

Study on Influencing Factors of Bearing Capacity of Cement Mixing Piles in Yasi Highway Subgrade

水泥搅拌桩在公路软基处理过程中,能够改善基础强度,显著提升软基的承载力。为研究水泥搅拌桩单桩承载力影响因素,进一步优化软土地基加固设计和处理提供指导,以牙克石至四平公路新站至大安嫩江大桥段工程为依托,运用有限元建模分析,同时结合载荷试验与无侧限抗压试验的结果,研究土体种类、养护龄期和水泥掺入量等因素对水泥搅拌桩单桩承载力的影响。结果表明,粉细砂强度略高于黑土并且优于粉土和细砂的强度;在当量配合比处于55~65 kg时承载力随着配合比的增加而增加;当养护龄期为3~28 d时,承载力变化情况与养护龄期成正比。有限元模拟验证了以上结果,该研究可为实际工程施工提供理论支撑。

Cement mixing pile can improve the foundation strength and the bearing capacity of soft foundation in the process of soft foundation treatment. In order to study the influencing factors of single pile bearing capacity of cement mixing pile, and to provide guidance for further optimization of soft soil foundation reinforcement design and treatment, based on the Yakeshi-Siping highway New Station to Da ’an Nenjiang Bridge project, finite element modeling analysis was used, combined with the results based on load test and unconfined compression test, the influence of soil type, curing age and cement content on the bearing capacity of single cement mixing pile was studied. The results showed that the strength of fine sand was slightly higher than that of black soil and better than that of silt and fine sand. When the equivalent proportion was between 55 kg and 65 kg, the bearing capacity increased with the increase of the proportion. When the curing age was 3-28 days, the variation of bearing capacity was proportional to the curing age. Finite element simulation verified the above results, which can provide theoretical support for practical engineering construction.