| Coal mining subsidence area is widely distributed in China, so it is very difficult for some highways to bypass mining subsidence area. The construction feasibility of highways in coal mining subsidence regions depends on the roadbed’s stability and lurking deformations under the vehicle load. According to the characteristics of the role that the vehicle flow affect on the roadbeds of highways located in coal mine subsidence areas, the dynamic load models of the coupled vibration of two-degree-freedom vehicle flow and road surfaces are established,and give out the expression form of load. Using numerical simulation methods, by means of establishing rock physical model after excavation of coal seam, to analyze the vehicle load, vehicle speed, pavement wavelength and amplitude with the influence of road pavement subgrade settlement value above goaf, moreover, the relationship are analyzed between the residual subsidence coefficient of subgrade and the vehicle dynamic loads, and the fitting formula is given. On the basis of the generalized mechanical structures, the paper has established the mutation instability models of the mining rock mass roof rock beam under the dynamic loads of vehicle flow, and derived the stability of the mining rock mass in coal mine subsidence areas by the analysis methods and judging criteria of the stability. Combining with engineering example, the Jin-Jiao highway roadbed stability is analyzed and calculated over mining area in Jiaozuo, and according to the national highway safety standards and requirements, the residual deformation of highway subgrade under the allowed maximum vehicle load is expected by probability integral method. Divide the stability region and make overall evaluation on the stability of highway. The research results are used to design, locate and plan the foundations of the buildings in coal mining subsidence areas. and to vehicle safety driving has an important reference and application value. |
