湖泊相软土真空堆载联合预压法的离心机试验研究

依托高速公路试验段真空堆载联合预压加固软土路基的现场试验，根据实际路基情况建立离心模型，对真空堆载联合预压加固湖泊相软土地基进行离心机试验，分析了在真空预压和堆载预压联合作用下软土路基的沉降规律，并将试验结果与现场监测结果进行对比，研究了两者沉降的关系。通过对比分析可知，采用真空堆载联合预压加固湖泊相软土路基，地基土在工期内的沉降占总沉降87%以上，加固效果明显；用该方法加固后软基的工后沉降发展缓慢，两年内工后沉降最多为2.5 cm，路堤断面沉降差不超过5 mm，不会影响公路正常使用；试验结果与现场实测值沉降趋势基本相同，但由于现场试验条件及离心试验误差影响，导致两者沉降值存在差异。

Centrifugal test study of vacuum combined with surcharge preloading of lacustrine soft soil

Based on the field test of vacuum combined with surcharge preloading reinforced soft ground in highway test section, the centrifugal model is built to perform the centrifugal test on vacuum combined with surcharge preloading reinforced lacustrine soft soil. The settlement law of soft ground under the effect of vacuum combined with surcharge preloading is analyzed. The test settlement is compared with the measured settlement in order to study the settlement relationship between them. By the above analysis and comparison, the results show that the settlement of soft ground during construction is more than 87% of total settlement under the effect of vacuum combined with surcharge preloading, which is effective to reinforce lacustrine soft soil. Using the vacuum combined with surcharge preloading to reinforce soft ground, the settlement development of soft ground after construction is slow; the settlement value of soft ground after construction is no more than 2.5 cm in two years; and the settlement difference of embankment section is less than 5 mm. It is clear that the settlement of soft ground after construction will not affect the normal operation of highway. The settlement trends of centrifugal test and field test are basically similar; but the settlement values of them have differences due to the impacts of the condition of field test and the errors of centrifugal test.