结合湖南洞庭湖区某高速公路淤泥质黏土软基处理工程,进行淤泥质黏土水泥改良土的无侧限抗压强度试验,研究水泥土无侧限抗压强度的影响因素、水泥土的应力应变关系和变形模量的变化规律以及试样的破坏模式。研究结果表明:淤泥质黏土水泥土的无侧限抗压强度随着养护龄期和水泥掺入比的增加而增加,随着含水率的增大而减小;无侧限抗压强度增长速率随着养护龄期的增大而减小,随着水泥掺入比的增大而增大;水泥土应力应变全过程曲线可以分为加载初始阶段、塑性上升阶段、应力~应变下降阶段和残余强度阶段等4个阶段;水泥土的变形模量随着水泥土的无侧限抗压强度的增大而增大;含水率高、水泥掺入比低和龄期短的试件呈现塑性破坏,而含水率低、水泥掺入比高和龄期长的试件呈现脆性破坏。
The mechanical properties of cement stabilized muddy clay from Dong-ting Lake area for highway soft soil foundation,was researched through the unconfined compressive strength (UCS )test,to analyze the influ-ence factors of unconfined compressive strength (UCS),the relationship of stress-strain,the change law of de-formation modulus,and the failure mechanism of test samples.The results indicate that the UCS of the speci-mens increases significantly with the increase of curing period and cement ratio.However,it decreases with the increase of moisture content.The growth rate of UCS increases with the increasing value of cement ratio.Never-theless,the decrease rate of UCS results from the increasing curing days.The overall stress-stain curve of ce-ment stabilized muddy clay is made up of four stages,i.e.,the initial leading stage,plastic growth stage,stress-stain decreased stage,and residual strength stage.The deformation modulus of cement stabilized soil increases with the growth of UCS.Plastic failure of the specimens could emerges with high moisture content,low cement ratio and short curing days.However,the fracture characteristics of the specimens with low moisture content, high cement ratio and long curing days would present fragile fracture.