Application of photogrammetry and in-situ test technology in the stability evaluation of gangue dump slope

In order to analyze the stability of the Lijiahao gangue dump slope and evaluate its impact on the safety of the industrial square, the geological survey and basement occurrence gangue dump investigation were carried out. The self-locking theory model was used to determine the stability of the basement. The three-dimensional topography of the gangue dump was measured by aerial photography. The in-situ test plan was designed to determine the comprehensive shear strength parameters of the gangue accumulation body. Used FLAC 3D to evaluate the three-dimensional stability of the slope. The results show that the cumulative length of the feathery crack on the top plate of the gangue dump exceeds 30 m, the main two cracks’ length exceeds 5 m, and the width reaches 5 cm. The settlement of several centimeters appears in the crack closure circle, which poses a direct threat to the industrial square. There is an “unlocking” section in the gully No.14 of the gangue dump base, and the residual thrust is less than the excess residual sliding-resistance force of the subsequent adjacent sections. The overall stability of the base meets the requirements. Based on the aerial photogrammetry results, the three-dimensional model of the waste dump is established, and the stability coefficient is 1.12. The cutting plane comparison analysis determines the stress–strain distribution law inside the gangue dump, proving that the stress distribution structure and strain range are consistent with the slope deformation law found in the field survey.