Deformation Stability Analysis of Foundation of Taijiao High-speed Railway above the Mined-out Area Affected by Rainfall

high-speed railway, taking the foundation of Taijiao high-speed
railway above the mined-out area of Dianshang, China as the
engineering background, a mechanical model of composite rock
strata of the foundation was established based on the theory of thin
plate. Combined with the catastrophe theory, the evaluation system
of the foundation stability was constructed. Using the selfdeveloped similar model test and rainfall device, the deformation
stability of the foundation under the condition of heavy rainfall and
dynamic loading of the high-speed railway was analyzed. Results
show that the maximum influence depth of the dynamic loading and
heavy rainfall on the foundation is about 20 m, and the further
compaction of the foundation cracks is the main factor leading to
the subsidence of the foundation above the mined-out area. In
addition, the increase of the number of longitudinal tensile cracks in
the foundation, which gradually plays a dominant role in the new
cracks, shows an exponential growth trend. Being affected by the
continuous heavy rainfall, the deformation evolution of the
foundation displays four stages: the initial stabilization, the slow
deformation, the first sudden-jump, and the secondary sudden-jump
stages. Among them, the surface's maximum deformation occurs in
the secondary sudden jump stage. The conclusions obtained in this
study provide a theoretical basis for the stability evaluation and
treatment of the foundation of the high-speed railway above the
mined-out area.