木质素对红黏土物理力学特性的影响

为了研究木质素对于红黏土特性的影响,对不同掺量下的木质素改性土进行界限含水率试验、pH实验,探究pH和改性土稠度界限的关系.对不同掺量,不同养护龄期下的改性土进行无侧限抗压强度试验,得到其不同掺量下的抗压强度、不同龄期下的抗压强度及其应力-应变曲线关系.试验结果表明:界限含水率、pH随着掺量的增加而增大,并且和掺量之间存在相应的曲线关系.无侧限抗压强度则随着掺量和龄期的增加而增大,当养护28 d,掺入量为8％时,相对于素土抗压强度提高2.93倍,并且养护龄期下的抗压强度和木质素的掺量存在线性关系,改性红黏土的破坏形态也由脆性破坏向塑性破坏发展.

Effects of lignin on physical and mechanical properties of red clay

To study the effect of lignin on red clay properties, the boundary moisture content test and pH experiment are carried out on the lignin modified soil with different content to explore the relationship between the pH value and the modified soil''s consistency boundary. The unconfined compressive strength test of modified soil with different content and curing age was conducted. The compressive strength under different content and curing age and its stress-strain curve relationship were obtained. The test results indicate that the limit water content and pH value increase with the dosage increase, in a corresponding curve relationship. The unconfined compressive strength increases with the increase of dosage and age. When curing for 28 days and the dosage is 8%, the compressive strength is increased by 2.93 times relative to plain soil. There is a linear relationship between the compressive strength and the lignin content, and the failure mode of modified red clay develops from brittle failure to plastic failure.