海口软土中细砂复合土的试验研究

Compound Soil Incorporation of Medium-fine Sands in Soft Soil in Haikou

对海口软土掺中细砂形成的复合土进行了系列试验研究,分析了不同围压下,不同配合比复合土与原状软土的强度、应力应变关系、压缩性以及有效应力路径的特性.试验结果表明:随着中细砂掺量的增加,于同围压下,复合土的剪切强度越高,剪胀现象越明显,复合土在低围压下表现出一定的应变软化,而在高围压下,无论是复合土还是原状土,其都表现出应变硬化现象;随着砂掺入量的增加,复合土的有效应力路径由斜线或弧形向"S"形过渡.

In the report, a series of tests on compound soil which mixed with medium-fine sands in soft soil in Haikou was performed. The strength, relationship between stress and strain, compressibility and the effective stress path properties of compound soil with different mix proportion and undisturbed soft soil under the different confining pressure were analyzed. The results indicated that with the increase of medium-fine sands in the soft soil, under same confining pressure, the greater shear strength, the more obvious the dilatancy; under the low confining pressure, compound soil showed strain softening, while under the higher confining pressure, two kinds of soils showed strain hardening phenomenon; with the increase of medium-fine sands in compound soil, the ef- fective stress path of compound soil converts from oblique line or are line to s-shape gradually.