Effect of Nano Silica and Steel Fibers on the Tensile Behavior of Lightweight Concrete

Low strength of aggregates reduces the strength of lightweight concrete, and its fragility prevents the ductile behavior of structures exposed to seismic loads. The use of reinforcing materials and fibers to compensate for the effect of reducing the strength caused using lightweight aggregate and preventing the sudden failure of concrete, can lead to the strength of lightweight concrete. The performance of the materials used is an effective parameter in determining the behavior of structural members. Therefore, to predict the behavior of structural members in computational finite element analysis, accurate behavioral models of materials are needed. In this study, the tensile behavior of lightweight structural concrete including steel fibers (with a volume percentage of 1%) and nano silica reinforcing pozzolans (with a weight percentage of 1% and 3%), respectively, and the effective parameters including tensile strength and the strain corresponding to the maximum stress is presented. The results show that the combined presence of steel fibers and nano silica has the greatest effect on improving the tensile behavior of lightweight concrete. With the addition of 3% nano silica and 1% steel fibers, the direct tensile strength of lightweight concrete has increased by 74%. Also, in all samples, the indirect tensile strength is slightly higher than the direct tensile strength. © 2023 American Institute of Physics Inc.. All rights reserved.