Application of Carbon-Fiber Composite Material in Micropile Structure

The flexural capacity of a single micropile is small, and some additional materials need to be built into the steel pipe to increase the flexural and tensile capacity of the structure. This paper introduced a new type of carbon-fiber micropile structure, and through comparison with a traditional micropile structure with ordinary steel, the carbon-fiber micropile structure is recommended. The results show that under the same geological and load conditions, the maximum pile top displacement of the carbon-fiber composite micropile decreased by 24% compared with that of ordinary micropiles. In addition, the displacement distribution of different pile positions showed that the stress and deformation of the carbon-fiber micropile are more coordinated and the resistance to soil displacement is improved. The maximum internal stress of the carbon-fiber composite micropiles was 1.53 times that of common-material micropiles, a relative increase of 53%, and the stress intensity of the piles was significantly improved. In terms of maximum shear stress, the maximum shear stress of the carbon-fiber composite at the squeezed end of the soil was 1.6 times that of the ordinary steel pipe pile, and the local shear resistance of the pile was improved under the premise of ensuring no brittle fracture.