Influence of HDPE Pipe Thickness and Confining Effect on Flexural Performance of Lightweight Concrete Beams

Abstract

The construction of RCC structure is generally time-consuming and if the construction site is in a remote area, then the transportation of the materials is a big issue. Moreover, if the construction is prefabricated then the members of the structure are very heavy to be lifted. One way to reduce the weight of the member is to use lightweight aggregate in concrete such as Pumice, but the efficiency of pumice is not as good as normal concrete. So, to improve the flexure capacity of the lightweight concrete the concrete will be confined with HDPE (High density polyethylene) Pipe. This research would concentrate on the design and efficiency against Flexure loading of the lightweight prefab beams that will serve as the structure member in order to achieve a lightweight portable structure. In this experimental setup, a total of 16 samples are casted, 12 of them are enclosed within HDPE (High-Density Polyethylene) pipes, while the remaining 4 samples are left without any casing and are considered control samples. Out of 16 samples 8 of them are reinforced with steel rebars. Three different thicknesses of HDPE pipe are used (8, 10, 16 inches). Parameters like load-deformation curves, pre-cracking, post cracking energies and energy dissipation are investigated. Results of the analysis confirmed that confining concrete with HDPE tube can effectively improve the failure mode, i.e., maintaining the system's integrity without any damage on the confining pipe, while increasing pipe thickness results in higher positive slope at postpeak branch of the load-deformation curve.