Study on the mechanical behavior of basalt-polypropylene fiber concrete: Insights from experimental testing and numerical simulation

This paper takes basalt-polypropylene fiber concrete as the research object, carries out the Brazilian splitting and uniaxial compression test, adopts acoustic emission (AE) monitoring and combines numerical simulation experiments with ABAQUS software to systematically study the effects on the mechanical properties of basalt fiber and polypropylene fiber concrete with different volume admixture. The test results show that the fiber admixture can improve the toughness of the concrete. The tensile strength and compressive strength generally show the trend of increasing first and then decreasing with the increasing volume admixture of fibers. The tensile strength increased maximum when the volume incorporation of basalt fibers and polypropylene fibers was 0.1% and 0.3%, respectively. The compressive strength is most highly increased when the volume incorporation of basalt fibers and polypropylene fibers is 0.2% and 0.1%, respectively. The AE activity with time could be divided into four stages, which coincided with the stress-time curves of the specimens. The accumulative AE counts reflect the number of cracks produced during the test, and the b-values reflect the crack expansion during the test. The addition of basalt fibers and polypropylene fibers can reduce the generation and expansion of cracks for the specimens and improve the strength of the specimens. Through theoretical analysis and numerical simulation, the addition of basalt fibers and polypropylene fibers helps to improve the peak strength and residual strength of concrete specimens, and the larger the volume admixture of fibers is, the greater the improvement of residual strength of fiber concrete specimens.