AUTHOR=Wang Hui , Zhou Jing , Cheng Jianhua , Dun Zhilin , Dun Zhiyuan 

TITLE=Impacts of train-induced dynamic loads on goaf foundation of Qinshui coalfield 

JOURNAL=Frontiers in Earth Science

VOLUME=Volume 10 - 2022

YEAR=2023

URL=https://www.frontiersin.org/journals/earth-science/articles/10.3389/feart.2022.1076910

DOI=10.3389/feart.2022.1076910

ISSN=2296-6463

ABSTRACT=For the high-speed railway built in the goaf sites, if the influence depth of the additional loads reaches the collapse fault zone of the goaf foundation, the overburden rock mass above the mined area will move again, causing the surface to deform again, which seriously threatens the construction, operation and maintenance of the high-speed railway lines. Therefore, in order to improve the safety and stability of operation of high-speed railway in the goaf sites, it is essential to determine the activation deformation of the goaf foundation. In this paper, based on the additional stress method, the newly added embankment materials are taken as uniformly distributed strip static loads and the high-speed railway in operation is regarded as the fluctuating concentrated dynamic loads. The 1/4 vehicle vibration model with two-degree-of-freedom is introduced, and the influence depth of the additional loads of the goaf foundation is calculated. The criterion of activation is proposed based on the relationship between the influence depth of additional loads and the height of collapse zone and fault zone. Such conclusions are drawn: (i) The activation judgment criterion for goaf foundation under the influence of high-speed railway vibration loads is recommended; (ii) Case study shows that the rail surface vibration model applicable to quantify the influence depth of high-speed railway above mined-out regions; (iii) The influence of rail surface irregularity on influence depth can not be ignored; (iv) The research conclusions can provide reference for site selection of high-speed railway and embankment deformation analysis.