灰色模型法预测真空预压土体的沉降量及固结度

Application of grey model method to vacuum preloading settlement and consolidation degree prediction

对真空预压加固处理的软土地基,土体的固结度是评价真空预压法加固土体效果的一个重要技术指标,而确定土体固结度的关键是土体最大沉降量的计算,沉降量的预估计算是否准确对工程影响很大.文章结合工程实例,依据真空预压法施工前期土体沉降量的实测数据,运用灰色理论建立了软基沉降的等时距预测GM(1,1)模型,预测土体最大沉降量及卸荷时的土体固结度,然后与目前实际工程中通常使用的三点法推算结果进行比较,结果说明:灰色模型法具有更好的预测精度,预测结果更符合工程实际,且能保证工程的安全性.

For the soft soil foundation reinforced by the vacuum preloading method, the consolidation degree of soil is an important index of evaluating vacuum preloading effects. The calculation of the largest settlement is the crucial factor of determining consolidation degree. The accuracy of estimating settlement will bring great influence to the engineering. According to pre-settlement measured data in vacuum preloading engineering examples, the even time-interval GM（ 1,1 ）is established, which predicts model of soft foundation settlement by using grey theory. Then the maximum settlement and consolidation degree of soil at the end of project are predicted. In comparison with the commonly-used three-point method in practical engineering at present, the results show that predictions of grey model method own a higher precision and are more in line with engineering practice, which can ensure the security of project.