摘要
根据数值计算提出了在地下洞室开挖爆破中,确定围岩松动圈的方法。给出了地下洞室开挖爆破的三维弹塑性损伤有限元计算方法。该方法论述了爆破荷载、重力荷载和开挖荷载的计算、施加以及迭代的方法,可以合理反应爆破对围岩稳定的影响和锚固支护施加的效果;结合岩石松动圈的实测方法,推导了判定围岩开始松动的损伤系数阈值公式,可以结合数值计算得到的洞周围岩损伤系数分布,确定在开挖爆破作用下围岩松动圈的范围。对实际工程的分析计算表明,根据数值计算判定的围岩松动范围与实测松动范围的规律基本一致,量值吻合较好,其结果为地下洞室开挖爆破的围岩松动圈的确定提供了有效的方法。
A numerical method to identify the range of excavation damaged zone（EDZ） induced by underground excavation and blasting is put forward.Firstly,the numerical approach for analyzing the underground excavation and blasting is presented based on three-dimensional elastoplastic FEM considering damage.This approach introduces how the blasting load,gravitational load and excavation load are calculated,applied and iterated.The influence of excavation blasting on surrounding rock stability and the effect of anchor support measures are both properly reflected.Based on the measurement method of EDZ in engineering practices,the threshold value of damage coefficient is obtained.Therefore,by employing the distribution of damage coefficients derived from numerical analysis,the range of EDZ of surrounding rock can be identified.A case study is conducted.It is discovered that the ranges of EDZ derived from numerical analysis and in-situ measurement agree well with each other;and the errors are within an acceptable range.It is therefore concluded that the proposed numerical method is effective to identify the range of EDZ of underground caverns induced by excavation and blasting.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2010年第8期2613-2618,共6页
Rock and Soil Mechanics
基金
国家自然科学基金重大研究计划(No.90715042)
国家杰出青年科学基金(No.50725931)
国家科技支撑计划(No.2008BAB29B01)
武汉大学优秀博士学位论文培育基金(No.2008-17)
关键词
开挖爆破
数值分析
损伤系数
围岩松动圈
地下洞室
excavation blasting
numerical analysis
damage coefficient
excavation damaged zone（EDZ）
underground cavern
