海相淤泥水泥土强度与变形特性试验及相互关系研究

Experiment on Strength and Deformation Characteristics of Marine Silt Cement Soil and Their Relationship

为研究海相淤泥水泥土抗压抗折抗剪强度与变形特性,通过开展水泥土系列室内配合比试验,测试不同固化剂掺量、龄期和水灰比下水泥土无侧限抗压强度fcu、抗折强度f_(f)、归一化抗剪强度τ_(qg)、归一化主应力差(σ_(1)-σ_(3))/σ_(3)及压缩模量Es等参数的变化规律,并对不同参数之间的相互关系进行了研究。结果表明:相同掺量下,水泥与石灰组合改良试样的性能比单掺水泥高2%~17%;水泥土强度与固化剂掺量和龄期成正比,与水灰比成反比,强度主要形成于成型早期阶段,且水灰比越小,早期的强度增长越快,大部分参数14 d龄期的结果已超过90 d的50%,28 d的强度则已达到70%;水灰比为0.5时,各项指标最优;此外,不同参数之间存在明显的线性关系,其中f_(f)、τ_(qg)、(σ_(1)-σ_(3))/σ_(3)、E_(s)分别为f_(cu)的0.33~0.35、0.35~0.37、9.58~10.31、17.27~17.66倍。

In order to study the compressive,flexural,and shear strength and deformation characteristics of marine silt cement soil,a series of laboratory mix ratio tests were carried out,so as to test the changes in unconfined compressive strength fcu,flexural strength f_(f),normalized shear strengthτ_(qg),normalized principal stress dif_(f)erence(σ_(1)‒σ_(3))/σ_(3),and compression modulus Es under different dosage of curing agents,curing ages,and cement-to-lime ratios.In addition,the correlation between different parameters was investigated.The results show that the performance of the improved samples with cement and lime is 2%‒17%higher than that with cement alone under the same dosage.The strength of cement soil is proportional to the dosage and age of the curing agents and inversely proportional to the cement-to-lime ratio.The strength is mainly formed in the early stage of molding,and the growth rate of the strength at the early stage accelerates with the decrease in the cement-to-lime ratio.The strength of most parameters at a curing age of 14 d has exceeded 50%of those at a curing age of 90 d,and the strength at a curing age of 28 d has exceeded 70%.When the cement-to-lime is 0.5,the above indexes are the best.In addition,there is an obvious linear relationship between dif_(f)erent parameters,with f_(f),τ_(qg),(σ_(1)‒σ_(3))/σ_(3),and E_(s) being 0.33‒0.35,0.35‒0.37,9.58‒10.31,and 17.27‒17.66 times of f_(cu),respectively.