摘要
结合边坡落石灾害现状,基于落石模型试验,系统分析落石质量、下落高度、垫层厚度、加筋位置、加筋材料等因素对落石冲击力及其动态演化的影响,揭示落石冲击棚洞的动力响应规律,结合垫层自重与落石冲击作用双因素影响确定垫层最优厚度,并对垫层设计提出优化建议。结果表明:随着垫层厚度增加,棚洞所受落石冲击力呈非线性减小,减小幅度先大后小而后趋于稳定;在同一垫层厚度下,棚洞所受落石冲击力随落石高度和落石质量近似呈线性增大;当复合垫层设计为“5 cm河砂+聚苯乙烯泡沫(EPS)+10 cm河砂”时,落石中心处土压力峰值相较于纯河砂垫层降低约60%,缓冲耗能效果最佳;通过多元回归分析得到了落石冲击力计算公式,且计算结果与实验数据吻合良好。
Combined with the current situation of the slope rockfall disaster,the influences of factors such as falling stone quality,falling height,cushion thickness,reinforcement position,reinforcement material and other factors on the impact force of falling rocks and their dynamic evolution are systematically analyzed based on the falling stone model test,the dynamic response law of falling rockfall impact shed caves is revealed,and the optimal thickness of the cushion layer is determined by combining the double factors of the self-weight of the cushion and the impact of falling rocks.Theoptimization suggestions for the design of the cushion are proposed.The results show that with the increase of the thickness of the cushion,the impact force of the falling rock affected by the shed hole decreases non-linearly,and the reduction amplitude is first large and then small,and tends to be stabilized.Under the same cushion thickness,the impact force of falling rocks affected by the shed cave increases linearly with the height of falling stones and the weight of falling stones.When the composite cushion is designed as“5 cm river sand+polystyrene foam(EPS)+10 cm river sand”,the peak earth pressure at the center of the falling rock is reduced by about 60%compared with that of the pure river sand cushion,and the buffering energy consumption effect is the best.Through multiple regression analysis,the formula for calculating the impact force of falling rocks is obtained,and the calculation results are well matched with the experimental data.
作者
叶四桥
王杰
曾彬
熊磊
马锐
YE Siqiao;WANG Jie;ZENG Bin;XIONG Lei;MA Rui(College of River and Ocean Engineering,Chongqing Jiaotong University,Chongqing 400074,China;Key Laboratory of Geological Hazards Mitigation for Mountainous Highway and Waterway,Chongqing Municipal Education Commission,Chongqing Jiaotong University,Chongqing 400074,China)
出处
《铁道标准设计》
北大核心
2024年第3期153-162,共10页
Railway Standard Design
基金
国家自然科学基金青年基金项目(42202322)
重庆市教委科学技术研究青年项目(KJQN202200719)
浙江省交通运输厅工程建设科研项目(2022-GCKY-01)。
关键词
棚洞
落石
模型试验
冲击力
加筋垫层
力学响应
计算公式
shed holes
rockfall
model test
impact force
reinforced cushion
mechanical response
calculation formula
