Properties of Light-weight Structural Leca Concrete in Precast Concrete Segments

In this paper, physical and mechanical properties of light-weight structural high-strength concrete using Leca, in precast segments, i.e. floors and partition walls, was studied by performing numerous experiments at Deesman factory. The smallest range of Leca clinker, i.e. 0-3 mm was used. The sand used was either 0-5 mm ordinary or storm sand. Admixtures used were Silica fume and SF800. Four standard cylindrical specimens were made for testing after 7 and 28 days of curing in bath. The experiments were made firstly using storm sand, and secondly with storm sand together with 0-5 mm sand for having a well-graded curve. The mix proportions were designed with or without silica fume. The ones made using silica fume were of strengths about the same as those of the ones without this admixture even though having more W/C ratios. The apparent surfaces of specimens made with silica fume and 0-3 Leca were smoother and softer than those of other specimens. In both double-T and hollow-cored sections, the weight of each segment was decreased around 30 percent in the most efficient design. Finally, the deflection of precast slabs under a uniform load equaling two times as much as the allowable load was tested and controlled satisfactorily.

Keywords:

Leca , light-weight concrete , slump , mix design , saturated surface dry (S.S.D.)