| With the development of city economy and traffic project, Human have seen the truth that Only to develop the underground railroad, fast traffic system which has the heavy carry so that the increasingly crowded city traffic problem will be solved. The hardcore of underground project is to ensure that it is safe belong the excavation,construction and the later permanent. Blasting construction is used commonly in the tunnel or underground project construction. Unavoidably the explosive shaking will affect the earth surface structure. When the explosive shaking exceeds special strength, it will produce damnification even destroy to concrete structure or wall rock. So it is very necessary to know the influence and characteristic of the wall rock stability caused by blasting earthquake live load, so that it will provide the foundation to the design and construction of blasting.Based on the ChongQing No.3 light track tunnel under the JiangBei airdrome, this article has take a study on its blasting preparatory design and blasting digging construction, as follows:First, the produce mechanism and transmit also attenuation rule in wall rock of blasting earthquake wave has been expatiated in theory.Second, Because the earth surface structure above this project is airdrome runway, which is different with other familiar buildings, this paper has expatiate the airdrome safety permanent standard.Third, based on the factors of blasting earthquake wave transmit and attenuation, at the same time, simple models was founded, we have educed the primary macroscopical factors which will effect the blasting results.At last, the tunnel blasting digging has been simulated by dynamical finite element software ANSYS/LS-DYNA , through the study to the displacement,velocity and so on of the earth surface airdrome runway nodes, it has give the reasonable range of the design parameters which will be primary factors to blasting function, so that the establishment of the blasting parameters will be guided.
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