Lightweight Self Compacting Concrete (Lwscc) in the Ready Mix

摘要

The paper describes a new field of development and use of self-compacting concrete (SCC using artificial light-weight aggregate based on burnt clay for coarse fraction of aggregate for transported ready mix concrete. There is experience of using common SCC for monolithic structures and prefabrication. The ability to produce light-weight structural self-compacting concrete of volume weight between 1600 and 1800 kg.m~(-3) and strength around 40 N.mm~(-3) shows new ways of development and use of SCC. The paper describes mixtures and methods for testing Theological properties of fresh concretes to fulfill parameters of self-compacting including description of testing apparatus and parameters observed. Different versions of mixtures are mentioned with sufficient physico-mechanical properties of hardened concrete - compression strength, tensile bending strength, static elastic modules and freeze resistance using artificial light-weight aggregate and active admixtures based on secondary raw materials (fly ash and other active admixtures - metakaolin, micro-silica). Problems of water-absorbing capacity of light-weight aggregate (up to 40%) are dealt with as well as problems of keeping stable consistency for 90 minutes time. In the conclusion, practical application of SCC lightweight floor structures are presented.