The invention provides a horizontal well collapse pressure determination method and device, equipment and a storage medium, and the method comprises the steps: for each well section of a target horizontal well, determining horizontal
principal stress corresponding to the well section based on the
rock mechanics parameters of the well section and a preset horizontal
principal stress formula, and determining the collapse pressure of the target horizontal well based on the horizontal
principal stress corresponding to the well section; the method comprises the following steps: accumulating the
liquid column pressure from 0 according to the cohesive force, the
internal friction angle, the formation pore pressure and the
effective stress coefficient which are obtained in advance, carrying out iterative
processing on a capacity function until the value of the capacity function is equal to 0, and further determining the
liquid column pressure corresponding to the capacity function being 0 as the collapse pressure corresponding to a well section. According to the method, the geostress model based on the micro-structure is used as a support, the influence of factors such as
liquid column pressure and borehole wall
percolation zone pore pressure change is considered at the same time, the collapse pressure is determined accurately and reliably, and
technical support can be provided for borehole wall stability of the deep
coal horizontal well,
optimal design of
drilling fluid density, reduction of underground complex accidents and improvement of drilling speed and efficiency.