特厚倾斜煤层采空区对公路路基沉降影响研究

为了研究采空区导致上覆复杂岩层运移致使公路路基沉降问题,以颗粒流理论为基础,通过下落法构建模型。根据煤层位置,假设了7种采空区长度进行模拟。模拟的结果为岩层应力、应变在不同情况下的最终状态,同时提出了影响区和松散堆积区的概念。结果表明,由于岩层构造复杂,在不同情况下主要影响区和松散堆积区的发展变化是不同的,特别是岩层4的作用较为特殊。根据公路路基设计规范,采空区只限于假设1和假设2的采空区范围内,路基沉降才能满足规范要求。

Impacts of the inclined and extremely thick coal seam goaf on the highway subgrade settlement

The paper intends to make an exploration of the impacts of the inclining and/or extremely thick coal seam goaf on the highway subgrade sinking on the basis of the particle drifting theory.We have developed a simulated model based on the particle drifting theory through the Particles Fall Method (short for PFM).And,then,we have made a simulated study for 7 kinds of goaf in accordance with the coal seam location in distance.The main results of the simulation can be represented in the final state of the stress and strain of strata in the different situations.At the same time,we have also brought about the concepts of the main influential area and the loose accumulation area,whereas we have also analyzed the changing laws with the idea of different goafs.The simulation results we have gained show that,due to the complicated rock structure and the impacts of the different lengths of goaf,the results of the main influential areas and loose accumulation areas prove to be different,particularly,for the influence of rock layer 4.It is the intrusive rock,the stiffness and strength of the rock,or the extremely large rocks,that tends to result in a very tough inhibit to prevent the transfer of deformation to the surface and the surface sinking under the subgrade range so as to meet the requirements for the first and second hypothetical cases.And in the more recent periods,it can likely turn to develop the loose accumulation area which functions as a resistance to the surface sinking.In spite of this,it remains highly probable that the concentrated inherent tension and compression stress may gradually lead to serious accidents.Therefore,in accordance with the code for design of highway subgrades (the surface settlement is less than 0.3 m),it remains of great need to restrict the length of goaf in response to the hypotheses 1 and 2 to meet the likeliness and needs of subgrade sinking.