摘要
为了研究动压巷道两帮煤体刚度劣化对顶板变形的影响,以大阳煤矿3405运输巷的地质及开采条件为工程背景,采用弹性地基梁理论、极限平衡区理论和现场监测手段,讨论了考虑与不考虑两帮极限平衡区内煤体弹性模量劣化情况下顶板位移的差异。结果表明:考虑与不考虑弹性模量劣化时,巷道顶板最大变形分别为267 mm和138 mm;考虑弹性模量劣化后顶板变形计算结果与实测结果平均误差减少了45.9%;顶板最大位移随弹性模量劣化程度降低呈指数降低,随极限平衡区宽度增加呈对数增加;采掘扰动导致两帮内裂隙发育,其等效弹性模量减小,两帮对顶板支撑能力减弱导致顶板位移增加,故基于巷道顶板变形设计支护方式时需考虑两帮极限平衡区内煤体弹性模量劣化的影响。
In order to clarify the influence of dynamic pressure roadway two sides stiffness softening on roof deformation,the geology and mining conditions of 3405 haulage roadway in Dayang Coal Mine are taken as the engineering background.Based on elastic foundation beam,limit equilibrium zone theory and in-situ monitoring,the difference of roof displacement with and without considering the deterioration of coal elastic modulus in the limit equilibrium zone of two sides is discussed.The results show that the maximum roof displacement is 138 mm and 267 mm respectively before and after the deterioration of coal elastic modulus.After considering the deterioration of elastic modulus,the average error between calculated and measured results of roof deformation is reduced by 45.9%.The roof displacement decreases exponentially with the decrease of the deterioration degree of the elastic modulus,and increases logarithmically with the increase of the width of the limit equilibrium zone.The excavation disturbance leads to the development of cracks in the two sides,and the equivalent stiffness decreases,the roof displacement increases due to the weakening of the supporting capacity of the two sides.Therefore,it is necessary to consider the influence of the deterioration of the elastic modulus of coal in the two sides limit equilibrium zone in the design of the roadway roof deformation support.
作者
张智敏
康天合
ZHANG Zhimin;KANG Tianhe(Key Laboratory of In-situ Modified Mining of the Ministry of Education,Taiyuan University of Technology,Taiyuan 030024,China)
出处
《煤矿安全》
CAS
北大核心
2021年第12期54-59,共6页
Safety in Coal Mines
基金
国家自然科学基金资助项目(U1810102,42072203)。
关键词
顶板位移
弹性地基梁
弹性模量
采掘扰动
极限平衡区
roof displacement
elastic foundation beam
elastic modulus
excavation disturbance
limit equilibrium zone
