玄武岩和聚丙烯混合纤维改良西宁黄土力学和热学特性分析

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中图分类号：TU444 文献标志码：A 文章编号：1000-0844（2025）05—1138—11

Mechanical and thermal properties of Xining loess reinforced by basalt-polypropylene hybrid fiber

WANG Yun1，LI Hui1'²，SUN Yuan¹ ，FAN Qi 1 ， ZHAO Mingze1 （1.College of Civil and Hydraulic Engineering，Qinghai University，Xining 810o16 ，Qinghai，China ; 2.Qinghai KeyLaboratoryofBuilding Energy Saving Materialsand Enginering Safety，Xining 810ol6，Qinghai，China）

Abstract： To systematically investigate the influence of fiber types and hybrid configurations on the mechanical properties of loess， this study conducted comparative reinforcement tests on

Xining loess from Qinghai Province using basalt，polypropylene，and their hybrid fibers. Conventional triaxial tests were performed to determine the optimal dosage of single fibers and the optimal blending ratio of hybrid fibers for Xining loess. The mechanical and thermal properties of unreinforced loess and hybrid fiber-reinforced loess under varying water contents （i.e.， 10% ， 12% ， 14% ， 16% ，and 18% ） and freeze-thaw cycles were evaluated. Scanning electron microscopy was utilized to assess the reinforcement mechanism at the microstructural level. The research results indicate the following： （l） At a basalt-to-polypropylene ratio of 3：2 ，hybrid fiber reinforcement improves the soil strength by 23.2% and 13.2% compared with basalt and polypropylene singlefiber reinforcement，respectively.（2） For hybrid fiber reinforced loess，cohesion and elastic modulus initially increase and then decrease with the increase in water content，peaking at a water content of 14% for maximum strength enhancement and best reinforcement effect； internal friction angle and thermal conductivity exhibit a decreasing trend with the increase in water content， although with smaller variations than unreinforced loess. （3） Under freeze-thaw cycles，cohesion，internal friction angle，elastic modulus，and thermal conductivity of the samples all show a decreasing trend. After 2O freeze-thaw cycles，the difference in strength loss rate between hybrid fiber-reinforced loess and unreinforced loess reaches a maximum of 9.8% . These results provide theoretical and practical references for the engineering design of hybrid fiber-reinforced soils.

Keywords： hybrid fiber-reinforced loess； triaxial shear tests；water content； freeze-thaw cycles;scanning electron microscopy （SEM）

0 引言

纤维加筋黄土是指在黄土中加入不同掺量的纤维。（剩余14681字）