Performance Characteristics of Cement Grout in Precast Construction

Abstract

Investigations on mechanical, elastic and performance of cement grout at different ages have been reported. The compressive strength of cement grout at the ages of 1 day, 3, 7, 28 and 90 days has been observed to be 40.10, 53.90, 60.30, 75.20 and 76.02 MPa respectively, while the corresponding flexural and direct tensile strengths are 6.1, 9.3, 9.6, 12.2, and 12.4 MPa, and 2.2, 3.15, 4.34, 6.02 and 6.49 MPa. The strength development in cement grout within 3 days has been observed to be excellent, while the strength development in 7 days is impressive. The strength development is normal up to 28 days and very negligible after 28 days. The direct shear strength of cement grout at 28 days is 3.6MPa. The bond strength of cement grout at 7 and 28 days have been observed to be 25.30 and 35.66 MPa respectively. The dynamic modulus of elasticity, quality and durability of cement grout have been found to be very well acceptable. Water absorption of cement grout is just 2.70%, which is well below limits. The anchorage bond strength of cement grout to be used for precast system has been observed to be extremely good in structures subjected to fatigue loading. The cement grout seems to be an excellent bonding material for various repair and precast concrete applications.