Stress-strain Relationship for Steel Fiber-reinforced Lightweight Aggregate Concrete under Uniaxial Compression

The current study presents a series of tests on steel fiber-reinforced lightweight aggregate concrete (SFRLWAC) cylinders in order to develop a stress-strain model for SFRLWAC subjected to compressive monotonic loading. In this experiment, steel fiber ratios of 0, 0.5, 1, and 1.5 percent by volume of the sample were used in the mixtures. The findings show that adding steel fiber to the lightweight concrete has a slight impact on the ascending branch of the stress-strain curve; however, it has a noticeable influence on the descending branch. The peak stress, strain at peak stress, and modulus of elasticity were investigated. To this end, some equations were established. To predict the complete SFRLWAC stress-strain curve, a stress-strain model was introduced and the validity of the model was explored. There was a good agreement between the proposed model data and experimental findings. Using ABAQUS software, numerical simulation of the SFRLWAC beams subjected to monotonic loading was conducted; the simulated results had an acceptable agreement with the experimental data.