Study On The Columnar Charging Direction’s Impact On Blasting Vibration

Blasting brings convenience and economy in construction, at the same time, it also brings many negative effects, for instance, as for blasting of ten thousands of tons of explosive charge, the influence of damaging effects of vibration caused by blasting on the environment should not be ignored, and there could be strong vibration among the middle and far areas of blasting and that might damage the environment around blasting. Therefore, how to make explosion energy applied to the effective aspects of rock mass’s breaking and throw shift and the aspects of relatively lowering the detriment of vibration damage caused by blasting as far as possible, and then to protect the safety of the surrounding environment is always a very concerned issue.Aiming at using detonation direction to adjust the energy acting on rock crushing or the energy caused by blasting vibration, this article analyzes and researches on it. That is to say, it uses the columnar charging detonation direction to change or to control the direction and the strength of the blasting vibration, and arranges shields in the opposite direction of detonation transmission to make detonation mainly transmitted in the direction of no shields, and it mainly includes the following aspects of works:(1)Using theoretical knowledge of the detonation and the detonation wave and analyzing the one-dimensional flow of detonation products and distribution of mass and energy of detonation products in the detonation direction in theory, and then the impact on the distribution of mass and energy of detonation products caused by the transmission direction of detonation wave could be worked out. Its characteristics could be reflected on the ground structural vibration effect from explosion elastic seismic waves, and through the wave equations and explosion seismic response spectrum, the ground structural vibration effect could be analyzed and described.(2).After the field blasting test, from analyzing the test data through the maximum velocity and the change of vibrating velocity increment and the law fitted by the Sadaovsk Formula, we could draw a conclusion:the maximum velocity in the positive direction of the same distances from explosive center is bigger than that in the negative direction; the maximum velocity in single direction reduces along the increase of distance from explosive center in a single direction; change of vibrating velocity at the near region is big in a single direction; vibrating velocity difference near the blasting region in the positive direction is obvious from that in the negative direction; and the blasting vibrating seismic wave direction law of vibrating velocity attenuating quickly in the positive direction of blasting.(3).Finally, through numerically simulating the columnar charging area near explosion and far from it by the ANSYS/LS-DYNA, and analyzing from equivalent stress cloud chart, time process curve and the law fitted by the Sadaovsk Formula, it is concluded the rule of columnar charging blasting vibration attenuation and directionality, and propagation directions of detonation wave will affect vibration velocity in different blasting directions, but it exists a critical distance in this phenomenon.In this paper, through theoretically analyzing the detonation wave propagation and blasting vibration, and combined with the field blasting tests and ANSYS/LS-DYNA numerical simulation, after the research, it is concluded that columnar charging detonation direction in certain critical distance will have an impact on blasting vibration. And for how to protect slope protection, surrounding rock, bed rock and reducing the blasting vibration near structures and buildings, it provides some certain theoretical basis and operation methods.