岩质路堑液态CO_(2)相变爆破充装量的试验研究  

Test on filling mass of liquid CO_(2)phase transition blasting in rock cutting

作　　者：程选生 刘华东 张尚龙 陈俭超 张万林 Cheng Xuansheng;Liu Huadong;Zhang Shanglong;Chen Jianchao;Zhang Wanlin(Western Engineering Research Center of Disaster Mitigation in Civil Engineering of the Ministry of Education,Lanzhou University of Technology,Lanzhou 730050,China;Key Laboratory of Disaster Prevention and Mitigation in Civil Engineering of Gansu Province,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学西部土木工程防灾减灾教育部工程研究中心,甘肃兰州730050 [2]兰州理工大学甘肃省土木工程防灾减灾重点实验室,甘肃兰州730050

出　　处：《土木工程学报》2023年第7期137-146,共10页China Civil Engineering Journal

摘　　要：为研究CO_(2)充装量对相变爆破振动的影响,进一步促进液态CO_(2)相变爆破在岩体开挖领域的应用。基于酒-额铁路工程,根据起爆经验模型设计不同CO_(2)充装量工况试验,选用VHL状态方程计算得出89型致裂器不同充装量的等当量岩石炸药量,对爆破试验结果、振动监测信号进行分析。结论是:(1)对于一般路基台阶,随着充装量减少,爆破能量逐渐降低,裂缝由台阶岩体表面及临空面充分发展转变为仅向致裂器射流方向1.5m范围内局部开裂;(2)CO_(2)爆破与传统化学炸药爆破相比振动影响区域较小,呈现出在近距离内爆破振动强度大且在爆心距4.85m左右处峰值质点振速(PPV)衰减至较小值的特点;(3)充装量对近爆和中近爆区域影响显著,随着充装量的增加,近爆及中近爆区域PPV值呈倍数增长,且中近爆区域的增幅更大,爆破振动能量频带分布逐渐由中低频频带流向极低频频带,能量分布及子频带数更加集中,实际工程中应利用微差爆破等方式避免低频集中高能量振动波对周边建构筑物的危害影响。To study the influence of liquid CO_(2)filling mass on phase transition blasting vibration and further promote the application of liquid CO_(2)phase transition blasting to the field of rock mass excavation,based on the Jiuquan-Ejina railway project and according to the empirical model,the tests for different liquid CO_(2)filling mass conditions are designed,the VHL state equation is used to calculate the equivalent rock explosive amount of the type 89 fracturing device with different filling mass,and the blasting test results and vibration monitoring signals are analyzed.The conclusions are that:①For the general subgrade steps,with the decrease of the filling mass,the blasting energy gradually decreases,and the crack development changes from the form of being fully developed on the surface of the step rock mass and the free surface to the form of partial cracking around the blast holes within 1.5m of the jet direction of the fracturing device;②Compared with traditional chemical explosive blasting,CO_(2)blasting has a smaller vibration-affected area,indicating that the blasting vibration intensity is large at close range and the peak particle vibration velocity(PPV)attenuates to a very small value when the blasting center distance is about 4.85m.③The filling mass has a significant impact on the blasting vibration of the near-explosive and the medium-near-explosive area.With the increase of the filling mass,the PPV values of the near-explosive and the medium-near-explosive area increase exponentially,and the increase in the medium-near-explosive area is even greater.The frequency band distribution of blasting vibration energy gradually flows from the mid-low frequency band to the extremely low frequency band,the energy distribution and the number of sub-bands are more concentrated.In practical projects,millisecond blasting and other methods should be used to avoid the harmful influence of low-frequency concentrated high energy vibration waves on surrounding structures.

关 键 词：岩石工程 路堑结构 液态CO_(2) 爆破振动 充装量 试验 

分 类 号：TU751.9[建筑科学—建筑技术科学]