Experimental And Study On The Blasting Of Porous Interlaced Air-interval Charge

In the construction process of blasting engineering,the charging structure plays an important role in controlling the blasting effect.The design of the charging structure is related to the crushing effect and economic cost of the blasting operation.At present,with the further improvement and development of blasting technology and theory,the new charging structure has been continuously proposed,more and more blasting construction began to use blasting excavation by means of interval charging,in which air-spaced charging structure is widely used.In the practical application of engineering blasting,air-spaced charge has a good effect on blasting results,the uniformity of blasting fragment and vibration.Therefore,how to better use the air-spaced charging technology to achieve the best blasting result is a specific problem that needs to be solved urgently in the current blasting construction process.This paper reviews the development of air-spaced charge technology at home and abroad,and systematically expounds the theory of rock blasting.The combination of numerical simulation technology and concrete model test is used to try to the further optimize of the three common air-spaced charge structures.Further optimization,a porous interlaced air-spaced charge structure was proposed,which mainly carried out the following work:(1)The main mechanical processes of rock failure is expounded systematically from the perspective of rock blasting theory,the characteristics of rock blasting are analyzed with two ways of air-spaced charge and continuous charge,and carefully summarized the theoretical model of rock blasting and the development process of the main blasting mechanics application program explores the principle and characteristics of air-spaced charge from the acadmic level;(2)Based on the current research and practice of three types of air-spaced charge structures at the top,middle and bottom of the blasthole,a model test scheme with three kinds of air-spaced charge modes between multiple holes is designed.Seeking the optimal ratio of air separation,and a theoretical foundation is laid for numerical simulation and model test,to better carry out experiments and research;(3)According to the model test scheme,the ANSYS/LS-DYNA software is used to establisha numerical model for the five types of charge structures: continuous charge,air interval at the bottom interval,top and,middle of the hole and porous interlaced air interval.From theoretically verifies proposed conjecture by nurmrial simulation calculation the compares and analyzes the results of numerical simulation calculations,and compares the respective characteristics of the blasting rock breaking effect of the 5 assembled drug structure model;(4)According to the model test scheme.The concrete module is placed at a construction site in Gui'an New District,further verify the numerical simulation results and conjectures with the actual effect of concrete model blasting,and compare and analyze the results of the model test,mainly from Stress strain,and blasting fragment to compare the characteristics and effects of blasting rock fragment of 5 assembled drug structure;(5)Through numerical simulation analysis and concrete model blasting test,it is found that the comprehensive effect of porous interlaced air-spaced charge is the best compared to other common three air-spaced charges,which can not only improve the blasting block degree,but also less installed.The blasting volume and the continuous charge of the drug can be minimized.