Basic mechanical properties of bagasse fiber-shale ceramsite composite lightweight aggregate concrete

Abstract The shale ceramsite concrete has become a critical recommended material in construction due to its excellent properties, such as lightweight, high strength, and thermal insulation. However, it has drawbacks, including brittleness and cracking vulnerability. For the purpose of improving the fundamental mechanical properties of the shale ceramsite concrete, this paper suggests adding the bagasse fiber, which is low-cost and widely accessible. First, the bagasse fiber is chemically treated with the silane treatment to reduce volume expansion caused by its high hydrophilicity and the degradation and weakened bonding induced by its poor alkali resistance during the cement hydration process. The electron microscopy is utilized to investigate the silane treatment modification mechanism on the bagasse fiber. Subsequently, several experimental tests were carried out on the bagasse fiber mortar and the bagasse fiber-shale ceramsite concrete. The results of the bagasse fiber mortar specimen tests indicate that the silane treatment can effectively improve the bonding performance between the fiber and the cement matrix. The effects of varying fiber dosages on the performance of the bagasse fiber-shale ceramsite concrete were explored in the mechanical test. The experimental results indicate that modified bagasse fiber markedly improves the performance of the shale ceramsite concrete, with the optimal fiber dosage identified, offering valuable insights for the advancement of sustainable, low-carbon building materials.