Improving cracking and drying shrinkage properties of cement mortar by adding chemically treated luffa fibres

• The relationship between different treatment conditions and crystallinity index was discussed.
• Microstructure of luffa fibres under different treated conditions were measured.
• The relation between luffa fibre content and cracking resistance and dry-shrinkage was described.
• Treated luffa fibres had a stronger effect on the early cracking than untreated luffa fibres.

This paper presents a study on the effect of luffa fibres by different chemical treatments of luffa fibres on cracking resistance and drying shrinkage of cement mortar. This research is aimed at using natural vegetable fibres to improve the performance of cementitious materials for sustainable construction. XRD was carried out to characterize the crystallinity of treated luffa fibres. By changing the chemical treatment parameters, the relationship between different treatment conditions and crystallinity index was investigated. SEM was used to characterize the microstructure of luffa fibres. The early cracking and drying shrinkage of cement mortar with the addition of treated luffa fibres were experimentally studied. The results revealed that treated luffa fibres had a stronger effect on the early cracking than untreated luffa fibres, while the effect on the drying shrinkage of cement mortar was comparable between treated and untreated luffa fibres.