针对建构筑物不同振速要求的隧道爆破药量计算方法

在城区进行巷道或隧道爆破时,许多建构筑物有不同的振速要求,同时满足多种被保护物振速的安全药量计算是一个设计难题。以重庆市隧道爆破为研究背景,建立隧道曲线、被保护物的空间轨迹方程;在地铁、文物建筑、地面建筑3种振速控制下,研究药量-桩号函数关系式:对位于隧道外侧的文物建筑,采用延长建筑物轮廓线将隧道分成若干段并推导相应Q-S分段函数;地铁安全药量根据隧道爆源点到地铁直线的空间垂直距离代入公式获得;其它建筑控制振速下根据爆源至隧道正上方地面距离进行药量计算;利用Matlab软件分别解算隧道各位置的3种药量值,并取其中最小值作为设计药量。

Computational method of blasting charges under different vibration velocity limits of buildings and structures around tunnel

Vibration velocities allowed for different buildings and structures around tunnel which is excavated by blasting are different in urban area.The computation of blasting charge which could control different vibration velocities within the value allowed for all nearby buildings was very difficult for blasting design in the past.With a case study of the tunnel blasting engineering in Chongqing city，the space loci equations of tunnel and the building protected outline are established.The functional relationship of the blast charge and tunnel site are respectively studied under three safe vibration velocities corresponding to the subway，the historic building and other buildings.The tunnel curve is divided into several sections by lengthening the building outline，the function about blasting charge and tunnel location is deduced for the historic building outside the tunnel.The blasting charge which vibration is controlled within safety standard is obtained by formula on the basis of space distance from detonating site to the line of subway.The blasting charge for other buildings is calculated based on that the ground above tunnel is distant from blasting point on the condition of vibration speed allowed.These three charge values at every position of the tunnel are calculated by Matlab program，and the minimum of three values is selected as the design blasting charge.