Stability analysis and protection design of mountain gas pipeline gabion retaining wall based on multi-objective optimization algorithm

Gas pipeline projects in mountainous areas are faced with complex terrain and geological conditions, and as a commonly used support structure, it is crucial to explore the stability of the gabion retaining wall. This paper takes the stability parameters of the gabion retaining wall as the research basis, and digs deeper into the influence of slope inclination, retaining wall spacing and other factors on the stability. Particle swarm optimization algorithm is introduced to optimize the design of gravity-type gabion retaining wall, through the construction of multi-objective optimization model, efficiently searching the design parameter space, optimizing the slope inclination angle, spacing and cross-section of retaining wall, and finding the optimal solution to meet the dual objectives of stability and economy quickly. The results show that the slope inclination angle α decreases after it reaches 25°, and there is an increasing trend under the condition of steep slopes over 60°. The thrust of the shallow soil bar on the retaining wall increases linearly with the increase of the retaining wall spacing. The average value of pressure calculation error of gravity retaining wall of this paper’s algorithm is reduced by 0.638kPa compared with the control group, so that the anti-slip stability of the retaining wall is improved by 0.435-0.487 compared with the control group, which can effectively reduce the pressure calculation error and improve the anti-slip stability of the retaining wall. The sensitivity of the cost of cantilever retaining wall to each condition parameter is, in descending order, surface load (1.481067) > fill weight (1.154368) > angle of internal friction (1.23317) > coefficient of friction of the substrate (0.896541).