沿海地区软土地基工程特性及加固措施研究

Research on Engineering Characteristics and Reinforcement Measures of Soft Soil Foundation in Coastal Area

以莆田市锦岚大道项目为背景,基于标准固结试验与十字板剪切试验,分析了该地区的软土固结特性整体表现。研究结果表明:随着固结压力增加,孔隙比与压缩系数呈减小趋势,减小速率随荷载增加逐渐降低;随着含水率的增加,一定压力范围内孔隙比减少越多,含水量大的土样容易被压缩;当固结压力0~100 kPa之间,压缩系数变化较大,超过100 kPa后,对应压缩系数改变量小。试验结果告知,软土地基沉降表现取决于含水率数值。依此,该工程采用堆载预压+塑料排水板的加固措施,地基承载力特征值由40 kPa增加至98 kPa,增幅118%,灵敏度由中灵敏度降至低灵敏度,处理后的地基承载力与稳定性大大提高,满足工程要求。

Based on the JinLan Avenue Engineering in Putian,the overall performance of the soft soil consolidation characteristics was ana-lysed by the consolidation test and the cross plate shear test.The Research indicates that:the porosity and compression coefficient show a decreasing trend as the consolidation pressure increases,and the rate of decrease gradually decreases with increasing load;as water content increases,the more the porosity ratio is reduced in a certain pressure range and the soil sample with larger water content is easy to be com-pressed;the compression coefficient changes greatly,between the consolidation pressure of 0-100kPa,and it changes little when consolida-tion pressure exceeds 100kPa.According to the test results,the water content is the key factor influencing soft soil settlement,the soft soil is planned to be reinforced with the measures of stacking preload and plastic drainage board,the bearing capacity of the soft soil foundation is increased from 45kPa to 98kPa,an increase of 118%,the sensitivity is reduced from medium to low.The bearing capacity and stability are greatly improved to meet engineering requirements.