Compressive behavior of rice straw-reinforced concrete for rigid pavements

Abstract

Micro-shrinkage cracking in concrete is normally observed at early stages. The cracking increases with the passage of time and affects the serviceability. The micro-shrinkage cracking can be avoided if its initiation is controlled by use of fibers. The utilization of natural fibers gains popularity in developing countries, including Pakistan, where vast resources of natural fibers are available as by-products with a low economic use. This paper primarily focuses on the utilization of locally available rice straw in concrete for rigid pavement application. The compressive behavior of rice straw-reinforced concrete (RSRC) is explored as per ASTM standard. The mix proportion of 1:2:4:0.6 (cement, sand, aggregate, and water, respectively by their weight) is considered for plain cement concrete (PCC) which is taken as reference. For RSRC, the length and content of rice straw are 25 mm and 1% (by wet volume weight), respectively. In addition to compressive strength, elastic modulus, absorbed energy, and toughness index of PCC and RSRC are experimentally determined and compared. The modulus of rupture is determined through empirical relation. Rigid pavements for PCC and RSRC are designed and compared using these parameters. The proposed rigid pavement design is discussed in detail.