Investigation on the deformation and energy dissipation behaviors for foamed concrete filled polyethylene pipe under quasi-static axial compression

Abstract

The long-term curing and defoaming issues within large volume foamed concrete during the on-site construction process could be efficiently resolved by fabricated foamed concrete filled polyethylene (FC-PE) pipes, which have significant potential for geotechnical and tunneling engineering for the design of large deformation and dynamic disaster. However, it is still unknown how filling action will affect FC-PE pipes that are subjected to axial load in terms of deformation and energy absorption. In this study, the FC-PE pipe and its individual components were investigated experimentally and theoretically. Results show that the initial peak load effect of FC-PE pipe is not particularly noticeable and the fluctuations of compression load are nearly periodic and uniform. In contrast to the individual components combined separately, the interaction of polyethylene pipe and foamed concrete filler can significantly increase the energy absorption capacity by more than 2.5 times. Given the dimensions of the polyethylene pipe, the effect of the foamed concrete density has a roughly linear positive correlation with the total energy absorption, the effective energy absorption, and the mean crushing force, whereas the densification displacement and the undulation of load-carrying capacity are in opposition. Based on the principle of energy, the theoretical mean crushing force FC-PE pipe was deduced accounting for the effective folding angle of the pipe wall and the interaction effect and their interaction, which of the corresponding errors of theory and experiment were between 11.8 and 17.7%.