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華中科技大學學報(自然科學版) 2020, Vol. 48 Issue (12): 102-107 DOI10.13245/j.hust.201218

欄目:土木工程
網孔形狀影響格柵道砟界面特性的細觀分析
苗晨曦 a , b , 李 杰 a , 朱孝振 a , 趙建斌 a , b
a. 太原理工大學土木工程學院,山西 太原 030024
b. 山西省交通科技研發有限公司,山西 太原 030027
摘要 為分析格柵-道砟界面力學響應以及網孔形狀對格柵加筋性能的影響,采用顆粒流軟件對三向和雙向土工格柵拉拔過程進行了仿真分析,揭示了剪切帶形成演化機制和剪切帶內粒間接觸力細觀組構特征;同時,從格柵原材料用量角度入手,比較兩種網孔形式土工格柵加筋性能.結果表明:界面強度不單受控于網孔有效面積,格柵拉拔力呈現出法向應力高度敏感性,實際工程中應根據荷載工況合理選擇土工格柵網孔形狀.
關鍵詞 三向土工格柵 ;雙向土工格柵 ;碎石道砟 ;拉拔試驗 ;離散元法
Mesoscopic analysis of influence of aperture shape on mechanical characteristics of geogrid ballast interface
MIAO Chenxi a , b , LI Jie a , ZHU Xiaozhen a , ZHAO Jianbin a , b
a. College of Civil Engineering,Taiyuan University of Technology,Taiyuan 030024,China
b. Shanxi Transportation Research Institute Group Co. Ltd.,Taiyuan 030027,China
Abstract In order to study the mechanical response of interface of geogrid-ballast and the influence of aperture shape on the reinforced performance of geogrid,the pull-out process of triaxial and biaxial geogrids were simulated by particle flow software.The evolution mechanism of shear bands as well as mesoscopic fabric characteristics of contact force within the shear bands was revealed.Meanwhile,the reinforced performance of two kinds of aperture shape was compared based on the material consumption of geogrid.Numerical results show that the interface strength is controlled non-monotonously by the effective area of the geogrid aperture,and the pull-out force of geogrid is highly sensitive to normal stress.Moreover,the interaction between the biaxial geogrid and ballast is strengthened under low normal stress conditions,thus the aperture shape of geogrid should be reasonably selected in engineering practice.
Keywords triaxial geogrid ; biaxial geogrid ; ballast ; pull-out test ; discrete element method
基金資助國家自然科學基金青年基金資助項目(51809191);中國博士后科學基金資助項目(2019M661065);山西省重點研發計劃項目(201803D31047);山西交通控股集團2020年度科技項目計劃(20-JKKJ-11)

中圖分類號TU 411
文獻標志碼A
文章編號1671-4512(2020)12-0102-06
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文獻來源
苗晨曦, 李 杰, 朱孝振, 趙建斌. 網孔形狀影響格柵道砟界面特性的細觀分析[J]. 華中科技大學學報(自然科學版), 2020, 48(12): 102-107
DOI:10.13245/j.hust.201218
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