水泥土桩加固航道边坡稳定性分析

Stability analysis of channel slope reinforced with soil-cement columns

水泥土桩作为水平向增强体用于航道土质边坡的加固工程中,加固边坡的稳定性计算没有相关规范参考,目前国内外对水泥土桩加固边坡的稳定性研究也鲜见文献报道。计算分析了水泥土桩加固航道土质边坡的稳定性,结果表明在桩土分算的情况下,极限平衡法计算的安全系数要大于有限单元法计算的结果,而桩土合算的情况下,极限平衡法和有限单元法将得到相同的结论。通过分析认为,桩体发生剪切、弯曲和转动等破坏模式,是极限平衡法与有限单元法计算结果产生差异的根本原因,当涉及土与结构物相互作用时,有限单元法与极限平衡法相比,前者结果更符合实际。水泥土剪力墙加固结构,可以防止桩体产生弯曲、转动等破坏,使加固边坡呈整体剪切破坏模式,有效发挥了水泥土桩的抗剪强度,从而提高边坡的稳定性。

As a horizontal reinforcement,soil-cement column is used in soil slope reinforcement project of channels. There are no relevant specifications in computing the stability of the reinforced slope for reference. Currently,the researches on stability of the reinforced slope with soil-cement columns are rare both at home and abroad. The stability of reinforced slope with soil-cement columns is calculated and analyzed in this paper. Results show that,under the column-soil separated model,the calculated results from the limit equilibrium method are larger than that from the finite element method,while under the equivalent area model,the results are almost the same. It is thought that failure modes of columns caused by shearing,bending and tilting are the root cause leading to result difference between the limit equilibrium method and the finite element method. When interactions between soil and its structure are involved,the finite element method is more applicable than the limit equilibrium method. The shear wall structure of soil-cement can prevent the columns from failure like bending,tilting and so on,and make the reinforced slope maintain a general shear failure,which having the soil-cement columns play an effective shear-resistance role. Accordingly,the stability of slope is improved.