硅藻土层水平抗力系数的比例系数m试验研究

Field Test of the Proportional Coefficient m of Horizontal Resistance Coefficient of Diatomaite Layer

硅藻土是一种特殊性质的土,其工程力学特性的研究相对较少,尤其是针对工程上常用的地基土水平抗力系数的比例系数(m)的研究更少。在硅藻土地层桥梁灌注桩水平承载力设计中,比例系数(m)的大小非常重要,却缺乏有效的取值依据。依托新建杭绍台高铁工程,在硅藻土试验区开展了3根灌注桩的水平静载荷试验,得到了桩侧地基土水平抗力系数的比例系数(m),根据硅藻土强度试验指标和相关规范方法进行计算,得到了白色、兰色和黑色三类硅藻土的比例系数(m),经验证与测试桩水平静载试验结果一致。研究成果可为硅藻土地层桥梁桩基或类似工程的设计参数取值提供参考。

Diatomite is a special soil with unique properties.However,its engineering mechanical properties remain poorly studied,especially on the proportional coefficient(m)of the horizontal resistance coefficient of foundation soils that commonly used in engineering.In the design of horizontal bearing capacity of bridge cast-in-situ piles in diatomaceous soil layer,the value of m is very important,but it lacks an effective value basis.In the new Hangzhou-Shaoxing-Taizhou high-speed railway project,a horizontal static load test of 3 cast-in-situ piles in the diatomite test area was carried out,and the proportional coefficient(m)value of the horizontal resistance coefficient of the pile-side foundation soil was obtained.According to the test indicators of diatomite strength and relevant specifications,the m values of three types of diatomite,i.e.,white,blue,and black,were calculated and determined,which were later proven to be consistent with the experimental results of horizontal static load of test pile.This research provide a reference for parameters determination in design of bridge pile foundation in diatomaceous soil layer or of similar sorts.