聚丙烯纤维与土壤稳定剂联合改良煤系土的应力-应变特征及其本构模型研究  

Stress-strain characteristics and constitutive model of coal bearing soil improved by combination of polypropylene fiber and soil stabilizer

作　　者：朱瑞 廖良健 周子敬 张淑怡 王志博 张鸿[1] ZHU Rui;LIAO Liangjian;ZHOU Zijing;ZHANG Shuyi;WANG Zhibo;ZHANG Hong(School of Civil and Architectural Engineering,Nanchang Institute of Technology,Nanchang 330099,China)

机构地区：[1]南昌工程学院土木与建筑工程学院,江西南昌330099

出　　处：《南昌工程学院学报》2025年第1期27-36,共10页Journal of Nanchang Institute of Technology

基　　金：国家自然科学基金资助项目(52068053);江西省南昌市优势科技创新团队项目(2017CXTD012)。

摘　　要：为了研究聚丙烯纤维与土壤稳定剂联合改良煤系土的应力-应变特征,采用常规三轴试验研究了土壤稳定剂掺入比对聚丙烯纤维与土壤稳定剂联合改良煤系土力学特性的影响。基于三轴试验结果,通过引入土壤稳定剂掺入比作为特征参数对邓肯-张模型进行修正,并对修正模型的准确性进行了验证。土壤稳定剂掺入比对联合改良煤系土的强度影响显著,当掺入比从1%增加至2.5%时,改良煤系土的黏聚力从115 kPa增加至176 kPa,增幅高达53%。采用聚丙烯纤维与土壤稳定剂联合改良的煤系土,其应力-应变曲线关系呈现出应变硬化特性,联合改良煤系土的初始切线弹性模量、体积模量以及极限主应力差均随着土壤稳定剂掺入比和围压的增加而增大,而土壤稳定剂掺入比和围压对联合改良煤系土的破坏比影响较小。修正后的邓肯-张模型预测曲线与三轴试验曲线基本一致,表明修正后的邓肯-张模型可较准确地表征聚丙烯纤维与土壤稳定剂联合改良煤系土的真实受力状态。In order to study the stress-strain relationship of coal measure soil improved by polypropylene fiber and soil stabilizer,the mechanical properties of soil stabilizer combined with polypropylene fiber and soil stabilizer were studied by conventional triaxial tests.Based on the triaxial test results,the improvement of the Duncan-Chang model by introducing the Ratio of soil stabilizer incorporation as a characteristic parameter,and the accuracy of the model modification were verified.The results show that the soil stabilizer content has a significant effect on the strength of the combined improved coal measure soil.When the incorporation ratio was increased from 1%to 2.5%,the cohesion of the improved coal measure soil increases from 115kPa to 176kPa,an increase of 53%.The stress-strain curve of the combined modified coal measure soil with polypropylene fiber and soil stabilizer shows a strain-hardening characteristic.The initial tangential elastic modulus,bulk modulus and limit principal stress difference of the combined modified coal measure soil increase with the increase of the Ratio of soil stabilizer incorporation and confining pressure,while the ratio of soil stabilizer incorporation and confining pressure have little influence on the failure ratio of the combined modified coal measure soil.The prediction curve of the modified Duncan-Chang model is basically consistent with the triaxial test curve,indicating that the modified Duncan-Chang model can accurately characterize the real stress state of coal measures soil improved by the combination of polypropylene fiber and soil stabilizer,which provides a theoretical guidance for its application in roadbed engineering.

关 键 词：煤系土 联合改良 聚丙烯纤维 土壤稳定剂 邓肯-张修正模型 

分 类 号：TU413.6[建筑科学—岩土工程]