中厚层吹填淤泥超软地基一次真空预压处理现场试验

Field test on one-time vacuum preloading treatment of ultra-soft soil ground with medium-thick fill of dredged silt

随着围海造地的发展,吹填淤泥越来越厚。对中厚层吹填淤泥超软地基提出一次真空预压法进行加固处理方式。现场试验采用有砂垫层和无砂垫层2种真空预压法对6~10 m中厚层吹填淤泥超软地基进行一次加固。通过现场监测对真空度、地表沉降、孔隙水压力、分层沉降等规律进行分析。通过加固前后土体抗剪强度和物理指标的对比,得知一次真空预压法对中厚层吹填淤泥超软地基加固效果明显。另外,试验结果显示,有砂垫层和无砂垫层2种真空预压法加固效果无明显差异。

As the land reclamation industry develops, the dredged silt will be hydraulically filled thicker and thicker, therefore it is proposed to employ the one-time vacuum preloading method to consolidate the ultra-soft soil ground with medium-thick fill of dredged silt. During the field test, the one-time consolidation improvement of the ultra-soft ground filled with 6 - 10 m thick of dredged silt is performed by two methods, i. e. vacuum preloading with and without sand cushion. Meanwhile, the vacuum degree, ground settlement, pore water pressure, layered settlement and other regularities are monitored and analyzed. Upon a comparison of shear strength and physical properties of soil mass measured before and after consolidation, it is shown that the ultra-soft ground with medium-thick fill of dredged silt is improved and consolidated remarkably using the one-time vacuum preloading method. In addition, the test results indicate that the two methods of vacuum preloading with and without sand cushion make no significant difference to the consolidation effect.