dating on mobile in india - Self consolidating concrete mix
Although there have been several studies on the effect of coarse aggregate content on the flow behaviour of SCC, enough attention has not been paid to quantify the effect of the shape of the aggregate.
In fact, river sand is simply not available in many areas.
Although there are studies that have shown that quarry run could be used as a filler instead of limestone for SCC, where X, Y, and Z are dimensions of the aggregate) to indicate the likely degree of potential compaction; values of index between 60 and 10 are cubic, between 30 and 60 indicate flakiness (100 for perfect cube), while values below 30 suggest elongation - Sphericity index to describe the polyhedral shape of the particle, and - Roundness index to describe the degree of angularity; values between 84 and 100 are angular, and between 52 and 68 are rounded Admixtures SCC invariably incorporates chemical admixtures - in particular, a high range water reducing admixture (HRWRA) and sometimes, viscosity-modifying agent (VMA).
Viscosity modifying agents The conventional method of improving the stability of flowing SCC is to increase the fines content by using a large amount of filler, reactive or inert.
Of late, however, attempts are being made to reduce the fines content (and paste content) to the levels of normal concrete (in doing so, reducing the potential for creep and shrinkage) and use viscosity modifying agents (VMAs) to improve the stability.
The Brite-Euram SCC project– has developed specifications and guidelines for the use of SCC that covers a number of topics, ranging from materials selection and mixture design to the significance of testing methods.