地基土的超固结特性对浅层平板载荷试验的影响

针对载荷板的形状、尺寸对超固结土浅层平板载荷试验的影响,分别采用不同形状、尺寸的载荷板,对坑底粗颗粒土进行浅层平板载荷试验.结果表明:荷载-沉降曲线在接近先期固结压力时出现一个平缓段;圆形载荷板的直径与方形载荷板的宽度相同时,圆形载荷板所测得的地基承载力特征值较大;随着载荷板尺寸的增大,地基承载力特征值逐步增大,并趋于收敛;与直径为0.1~0.3 m载荷板的试验结果相比,直径为0.6~0.8 m载荷板的试验结果稳定性较好.

Effect of over-consolidation characteristics of foundation soil on shallow plate loading test

In order to research the influence of shape and size of loading plate on the shallow plate loading test for the over-consolidated soil, the shallow plate loading test for the coarse-grained soil at the bottom of foundation pit was carried out through adopting the loading plates with different shape and size. The results show that a flat section appears near the preconsolidation pressure on the load-settlement curve. When the diameter of round loading plate is the same as the width of square loading plate, the characteristic value of bearing capacity of foundation soil, which is obtained with the round loading plate, is larger. With increasing the size of loading plate, the characteristic value of bearing capacity of foundation soil gradually increases and tends to be convergent. Compared with the experimental results of loading plate with the diameter between 0.1 m and 0.3 m, the experimental results of loading plate with the diameter between 0.6 m and 0.8 m have better stability.