冻融条件TG固化剂石灰土基层性能研究

Performance research on the calcareous soil foundation with TG curing agent under freeze and thaw cycles

为了进一步研究TG固化剂石灰土在冻融条件下的各项性能,分别对TG固化剂石灰土进行冻融作用前后的无侧限抗压强度试验和劈裂试验以及干缩试验.结果表明:随着冻融循环次数的增加,无侧限抗压强度以及劈裂强度逐渐减小,经历8次冻融循环以后强度衰减达到最大值.经过冻融循环作用后试件的无侧限抗压强度以及劈裂强度残留值随着含水率和压实度的增加而增加,通过冻融试验得到的抗冻性能指标BDR值在51%以上,与未饱水冻融循环得到的最终残留强度值保持一致.经冻融循环作用后TG固化剂石灰土的干缩应变和干缩系数减小,干缩性能有所提高.冻融循环条件下TG固化剂石灰土抗冻性能良好,可以应用于路面基层.

In order to further study various properties of calcareous soil with TG curing agent under freeze and thawcycles,unconfined compressive strength test,split test and dry shrinkage test were carried out on the soil before and after freeze-thawcycles. It is found that with the increase of freeze-thawcycles,the unconfined compressive strength and splitting strength decrease gradually; after eight freeze-thawcycles,the strength attenuation reaches the maximum. The residual values of unconfined compressive strength and splitting strength increase with the moisture content and the degree of compaction after freeze and thawcycles; the antifreeze performance index due to freeze and thawcycles is above 51%,which is consistent with the final residual strength of unsaturated water experimented freeze and thawcycles. Dry shrinkage strain and dry shrinkage coefficient of the calcareous soil with TG curing agent decrease after freeze-thawcycles,and the dry shrinkage performance has been improved. Freeze-thawcycles have an opposite effect to the strength and dry shrinkage performance of calcareous soil with TG curing agent. Calcareous soil with TG curing agent has good frost resistance under freeze and thawcondition,which can be applied to pavement foundation.