Shear characteristics and design for high strength self consolidating concrete
Self-consolidating concrete (SCC) is a stable and cohesive high consistency concrete mix with enhanced filling ability properties that reduce the need for mechanical compaction.Limited standards and specifications have been reported in the literature on the structural behavior of reinforced self-compacting concrete elements. However, to date limited research exists exploring the use of coarse RCA in SCC. The utilisation of recycled concrete aggregate (RCA) in Self-Compacting Concrete (SCC) has the potential to reduce both the environmental impact and financial cost associated with this increasingly popular concrete type.This was capable of flowing under its weight through restricted sections with no segregation and bleeding.This material needs to have a relatively low yield value in order to guarantee a high flow capability and a moderate viscosity to resist segregation and bleeding.However, the use of RCA may potentially reduce concrete quality as coarse RCAs are generally of poorer quality than natural coarse aggregates, with greater water absorption [3, 4] and lower density .This reduced quality is due to the fact that coarse RCA consists of both original aggregate and adhered mortar; thus the quality of the RCA depends not only on the original aggregate, but also on the quality and quantity of adhered mortar.
SCC, as a highly workable concrete, was first introduced in the late 1980s in Japan ().Use of SCC can also help minimize hearing-related damages on the worksite that are induced by vibration of concrete.Another advantage of SCC is that the time required to place large sections is considerably reduced.Research studies in Japan are also promoting new types of applications with SCC, such as in lattice type structures, casting without pump, and tunnel linings.Since the development of SCC in Japan, many organizations across the world have carried out research on properties of SCC.
At present a large portion of potentially useful construction and demolition waste is disposed of in landfill sites, creating environmental problems due to scarcity of such sites, unplanned disposal, and environmental cost of transporting demolition waste .