Study On High Pressure Compaction And Filling For City Pile Foundation In Goaf

The goaf has become a major obstacle to the development of resource-based cities.Since the time of destruction occurrence of the goaf are difficult to predict,it is difficult to take measures to prevent it in advance.Therefore,in order to reduce the impact of the goaf on the ground buildings,it is necessary to manage the goaf before construction.The paper mainly studies the high-pressure compaction filling method used in construction of urban pile foundation affected by goaf,in order to propose a feasible construction process,filling material ratio and perfusion pressure for the high-pressure compaction filling method.The method help to solve practical engineering problems and provide technical reference for subsequent similar urban pile foundation construction.This paper reviewed the advantages and disadvantages of common goaf control methods and their applicable scope,and analyzed the geological conditions and engineering difficulties with the Anshan Ziyu Huafu project as the background.According to the characteristics of the underground goaf in the city,the high-pressure compaction filling method was proposed.It is the key to study the determination of mix ratio,perfusion pressure and suitable treatment inspection methods.And the necessity of expanding the scope of governance was proposed.After determining the construction process,the mix ratio range,perfusion pressure and diffusion radius through experiments were determined,the key data of the construction was clarified,the key parameters was defined during the high-pressure infusion construction process,and the construction process and precautions were briefly described.The numerical analysis was carried out by Flac3D software to analyze the influence of the goaf on the building and the effect of filling treatment,reproducing the stability of the construction process and providing reference for the treatment process.The need to expand the scope of governance was demonstrated by comparison.After the completion of the goaf treatment,ring-hole method、Single-hole wave velocimetry、Pile foundation survey、declivity survey、settlement survey were used to test the treatment effect to determine the completeness of goaf filling and the filling effect.Through the long-term monitoring,the accumulated data of building settlement was obtained,and the settlement data obtained by numerical analysis was compared to determine that the settlement was as expected.Through the actual project,it is determined that the high-pressure compaction filling method in the goaf in the urban area is safe and reliable,and the conditions required for the pile foundation construction can be effectively achieved.It will provide a basis for the application of ground treatment methods in the goaf in the future,and provide reference for evaluation research in related fields.