摘要
爆破时周边眼属于两端封闭结构,从经典的薄壁内压圆筒理论着手,推导应变能方程与聚能状态下能量分配关系,根据破坏准则对该法周边眼参数进行设计,提出一种隧道聚能光面爆破周边眼参数的确定方法。以张家界吴家边隧道为例,利用此新方法计算其周边眼参数,并结合现场实际的光爆效果,探讨该方法的可行性和计算精度问题。研究结果表明:当聚能装置上聚能缝宽度增大时,往聚能切缝缝两侧汇聚的能量越多,周边眼炮孔间距越大,相同药量作用下破岩效果更佳;聚能影响因素λ增大时,即聚能装置刚度越强,可使周边眼间距显著增大。若取相同周边眼间距,在有聚能装置存在的情况下可减少炸药用量来达到相同光爆效果;围岩等级越高,岩石抗拉强度越强时,周边眼间距明显减小,随聚能影响因素增大,周边眼间距略有增加。在使用该方法计算周边眼间距时,爆破后产生的残余炮孔占95%左右,光面爆破效果良好,可为类似工程提供参考。
When the tunnel is blasting, the surrounding holes belong to the closed structure at both ends, based on the classical thin-walled cylinder theory, the relationship between strain energy distribution in the state of energy accunulation is deduced, by failure criterion on the laws surrounding hole parameters are designed, proposed a tunnel shaped method of determination of parameters of smooth blasting around the eyes. A case study of Zhangjiajie Wu side tunnels, using this new method of calculating the surrounding hole parameters, and actual light burst effects, explored the feasibility of the method and accuracy problems. The results show that when the shaped device shaped seam to seam width increasing, the more energy on both sides together, around the hole spacing is greater, the cock breaking effect is better under the same explosive quautity;increasing factors, namely shaped device stiffness is strong, can make the surrounding eye spacing increased significantly. If we take the same around the eye spacing, the presence of the energy collection device can reduce the amount of explosive to achieve the same effect of smooth blasting;surrounding rock grade is higher, the tensile strength of rock is stronger, the surrounding eye spacing decreases obviously, increase the influence factors of cumulative peripheral hole spacing increased slightly. When using this method to calculate the distance between adjacent eyes, the residual hole produced after blasting accounts for about 95%. Smooth blasting effect is good, which can provide reference for similar projects.
作者
耿大新
陶彪
于洋
黄龙华
GENG Daxin;TAO Biao;YU Yang;HUANG Longhua(School of Civil Engineering and Architecture, East China Jiaotong University, Nanchang 330013, China)
出处
《铁道科学与工程学报》
CAS
CSCD
北大核心
2019年第2期435-442,共8页
Journal of Railway Science and Engineering
基金
江西省交通运输厅科技资助项目(2016D0039)
江西省普通本科高校中青年教师发展计划访问学者专项资金资助项目
关键词
周边眼间距
应变能
聚能管
光面爆破
curved ground wall
strain energy
shaped blasting
smooth blasting
