基础埋深对承载力离心模型试验中粒径效应的影响

Influence of foundation depth on particle size effects in centrifuge tests on bearing capacity

利用modelling of models的方法研究基础埋深对圆形浅基础承载力离心模型试验中的粒径效应的影响规律。使用的地基材料为经过粒度调整的河砂,其平均粒径为0.6 mm,模型基础直径为5～40 mm,模型基础直径与地基材料平均粒径的比值在8.3～66.7之间,模型基础埋深与直径的比值为0,0.5和1.0;模拟原型直径为200～1500 mm。利用粒径效应评价指标对试验中的粒径效应进行定量讨论,结果表明,随着基础埋深的增大,粒径效应的范围及对试验结果的影响程度减小。同时,给出粒径效应范围图,用于选择合理的模型基础尺寸或地基材料尺寸。

The influence of foundation depth on the particle size effects of the circle shallow foundation in centrifuge tests on bearing capacity is studied by modelling of models.In the tests,the ground is made by the river sand whose grain diameter is adjusted by sieving and the mean grain diameter is 0.6 mm.The diameter of the model foundation changes from 5 to 40 mm and the ratio of the foundation diameter to the mean grain diameter is 8.3 to 66.7.The ratio of the depth to the foundation diameter is 0,0.5 and 1.0,respectively,and the equivalent foundation diameter is 200 to 1500 mm.The evaluating index is used to discuss the particle size effects in the test.The results show that the influence of the particle size effects decreases with the increase of foundation depth.Based on the test results,the figure indicating the scope of the particle size effects is deduced,and it can be used to choose the reasonable model foundation size and the ground materials.