Analysis On Roof Deformation Based On Thin Plate Theory

In this paper, the roof deformation law and loading characteristics of first weighting and periodic weighting stage were studied systemically by means of theoretical calculation and the similar simulation experiment. Elastic thin plate theory was introduced in the study of rock blocks. Basing on the difference of the structural characters among each stage, four mechanics model that, the four edges clamped,both sides clamped and simply supported on other both sides, both sides clamped and other both sides free, and one side clamped the opposite side free and the other two edges simply supported,were set up and solved. The solving problem of balance differential equation of the thin plate theory was turned into a matrix calculation problem of node deflection by using the method of finite difference. And then solve the matrix establishing of finite difference method by using the matlab software. And finally, solve the internal force by using the Visual Basic calculation program which was wrote by the author. The breaking position and breaking plate features of various models was predicted basing on the calculation results.Secondly, taking a nearly horizontal mining face of Miluo mine as engineering background, using the method of analog simulation experiment, a similar physical model was established to simulate the field recovery. In the process of the advancing of working face, the sinking and breaking laws of immediate roof from the first phase to periodic phase were studied by similarity simulation experiment. At last, making a comparative analysis between the theoretical calculation results and similar simulation experiment results, it is concluded that, the better mechanics model if roof in the first stage to choose is the both sides clamped and both sides simply-supported model, the better mechanics model of the phase in periodic to choose is the one side free while the opposite clamped and other both sides were simply supported. Basing on the consistence of the theoretical calculation results and the similar simulation experiment results, it is shown that the result of theoretical calculation and the analogsimulation were reliable. The study of roof was enriched and the theory of thin plate was developed by the research of this paper. A new theoretical basis and a new method were provided for the coal mine roof study of our country. A certain reference was also provided to the subsequent scholars on the setting of the mechanics model.