Performance of lightweight concrete one-way slabs using medium-K basaltic andesite pumice and scoria

Abstract

An investigation was conducted on bending tests of 24 reinforced lightweight concrete one-way slabs using medium-K basaltic andesite pumice and scoria and 1 reinforced normal concrete slab as a control. The compressive strengths and reinforcement ratios were varied to evaluate their flexural behaviors. The ultimate bending moment at failure, midspan deflections and maximum crack widths at assumed service, cracking patterns and failure modes were evaluated to indicate their performance. The results showed that medium-K basaltic andesite pumice and scoria as coarse aggregates can be used to produce pumice and scoria concrete one-way slabs with a relative satisfactory performance. Both behaved typically as reinforced concrete beams with first cracking load, ultimate load and stiffness were lower than the control. The reinforcement ratio was an important factor that influenced significantly the observed parameters compared to compressive strength and type of coarse aggregates. Theoretically, the ultimate bending moment can be estimated accurately by provision compared to midspan deflection and maximum crack width. Cracking patterns were a typical flexural crack, while failure modes were a reinforcement yielding without spalling on compressive concrete zone.