Development of light weight concrete using pumice aggregate its behavior under the static and cyclic loading

Abstract

Application of lightweight concrete in construction works has been growing rapidly in recent years due to its advantages over ordinary concrete. In this investigation, pumice breccia is proposed as the coarse aggregate instead of the ordinary concrete. The main purpose of structural grade light weight concrete is to reduce the weight and to construct larger precast units. It is possible to develop light weight concrete using pumice with a dry density of 1200 kg/m3 up to 1450 kg/m3. The present work investigated the mechanical properties of lightweight concrete and control concrete: compressive strength, splitting tensile strength, modulus of elasticity. It also examined durability properties like acid resistance and water absorption for all types of lightweight and control concrete at 28 days of curing. The significant advantages of lightweight concrete were found to be reduced mass and proper maintenance of adequate strength. Static load testing of light weight concrete of six concrete beams, three control and three light weight, with M30 grade with length (L) 1500 mm, breadth (B) 100 mm, depth (D) 150 mm were cast and tested in the laboratory. The beams were tested under two-point load condition in a loading frame capacity of 50 tons. Deflections were measured through appropriate instruments. The load was applied until the ultimate failure occurred. The load at which the diagonal crack and the ultimate shear crack developed was also recorded. Crack patterns were marked on the beams. The parameters studied were ultimate flexural capacity, load deflection behavior and moment curvature relationship, and stress vs strain relationship. The number of cracks crack propagations, and crack spacing were studied at initial, service, yield and ultimate load levels. newline