一种新型水泥固化土的试验研究  

Experimental study on new variety of cement-stabilized soil

作　　者：邵玉芳[1] 徐日庆[2] 刘增永[2] 龚晓南[2] 

机构地区：[1]浙江大学生物系统工程系,浙江杭州310029 [2]浙江大学土木工程学系,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2006年第7期1196-1200,共5页Journal of Zhejiang University：Engineering Science

基　　金：浙江省教育厅基金资助项目(316101G20454)

摘　　要：通过三轴试验、直剪试验和压缩试验,对一种掺有添加剂的新型水泥固化土进行了研究.在100、200、300kPa的围压下,对3种不同配方的水泥土试样:普通配方(水泥掺入量15%)、新配方(水泥掺入量11%,添加剂掺入量0.15%)和增强配方(水泥掺入量15%,添加剂掺入量0.15%)进行三轴固结不排水剪切试验,结果表明,添加剂能显著提高水泥土的强度,围压增大对普通配方水泥土强度的影响不显著,而新配方和增强配方水泥土的强度分别提高了20%和26%,新配方水泥土的峰值强度比普通配方高40%,增强配方水泥土的峰值强度又比新配方高60%;3种配方的水泥土和水泥土-土复合试样直剪试验结果表明,添加剂能显著提高水泥土的抗剪强度,且抗剪强度与垂直压力成正比,3种配方水泥土的抗剪强度-垂直压力曲线基本平行.压缩试验结果表明,添加剂对水泥土压缩性的影响不显著.根据三轴试验结果,建立了掺入复合添加剂的新型水泥固化土的本构模型,该模型摆脱了传统流动法则的束缚,经试验验证更加符合水泥土的实际情况,模型还表明主应力对塑性变形有较大的影响.A new variety of cement-stabilized soil with additive was studied by consolidated undrained triaxial test （OU test）,direct shear test and compression test. OU tests were done with confined pressures of 100.200.300 kPa,with regular formula （15% cement） . new formula （11% cement and 0.15% additive） and enhanced formula （15% cement and 0.15% additive）. Results showed that the additive could dramatically increase the strength of the cement-stabilized soils. Accretion of confined pressure could increase the strength of the cement-stabilized soils with new formula and enhanced formula by 20% and 26%, respectively,but did not affect the strength of the cement-stablized soils with regular formula. Direct shear tests of cement-stabilized soils and cement-stabilized soil-soil composites showed that the additive could dramatically improve the shear strength of the cement-stabilized soils. The shear strength was proportional to the vertical stress p,with the three p-curves being almost parallel to each other. Compression tests showed the additive had little effect on the compressibility of the cement-stabilized soil. Based on the results of laboratory tests,a constitutive model of cement-stabilized soil with enhanced formula was established that got rid of the flow rule limit and reflected the cement-stabilized soil more realistically. The model also indicated that the ratio of principal stress played an important role on the plastic deformation of the cement-stabilized soil.

关 键 词：水泥土 添加剂 土工试验 本构模型 

分 类 号：TU411[建筑科学—岩土工程] TU472.5[建筑科学—土工工程]