Toughness improvement of low strength ceramsite lightweight concrete by polypropylene fiber and recycled rubber particle

In order to improve the crack resistance toughness and investigate the capillary water absorption (sorptivity) characteristics of ceramsite lightweight concrete (CLWC), the current study has examined the performance characteristics of locally accessible polypropylene (PP) fiber and rubber-reinforced lightweight concrete. An investigation on CLWC's strength, ductility, and sorptivity was addressed in this research. This study examined how fiber and rubber affect CLWC characteristics. Thus, the experiment maintained concrete mix design and fiber and rubber properties while varying fiber and rubber dosages from 0.05% to 0.15% and 0.5–1.5%. Multiple tests on CLWC specimens showed promising compressive, flexural, and toughness results. In the sorptivity test, fibers inhibit CLWC water absorption, assessing lightweight concrete porosity and permeability. SEM examined the ceramsite, rubber, fiber, and mortar interaction microstructure. Notably, strength capacity significantly improved compared to conventional lightweight concrete. Beam flexure testing indicated a maximum 62.79% toughness enhancement. Additionally, the first-crack load increased by 31.83%, and the ultimate load increased by 32.34% over control beams. The macro crack strength of interconnecting structures is improved by fiber and rubber. Several energy dissipation pathways gave ceramsite lightweight materials enhanced flexural toughness.