Effect of expanded slate aggregate on fresh properties and shear behaviour of lightweight SCC beams

Abstract

Lightweight normal concrete (NC) and self-consolidating concrete (SCC) mixtures were developed using lightweight expanded slate coarse aggregate. The developed mixtures incorporated natural sand, metakaolin (MK) and fly ash (FA), and had a density in the range 1817-1984 kg/m 3 . All the mixtures were developed with variable compressive strengths (20-61 MPa), lightweight expanded slate to fine aggregate (ES/F) ratios (0 . 7-2 . 0), water to binder (W/B) ratios (0 . 35 and 0 . 40) and variable total binder contents (500 kg/m 3 and 600 kg/m 3 ). Tests of the fresh properties of the developed lightweight SCC mixtures included flow/passing ability, viscosity and segregation resistance tests. The developed lightweight NC and SCC mixtures were also used to cast 12 identical beams without shear reinforcement to examine their shear strength and cracking behaviour in full-scale concrete structures. The results of the trial mixtures performed on a wide range of ES/F ratios showed that a maximum ES/F ratio of 1 . 5 could produce lightweight SCC mixtures with acceptable fresh properties and compressive strength, while a maximum ES/F ratio of 2 was able to produce NC mixtures. Although an increase in ES/F ratio decreased the density of the SCC mixtures, it decreased the 28 d compressive strength, reduced the mixture flow ability and passing ability, and increased the segregation risk. However, increasing the ES/F ratio increased the normalised shear loads and post diagonal cracking resistance of all the tested beams. This is because the tested expanded slate aggregate proved to be relatively strong as it did not entirely break along the diagonal crack surface, even in mixtures of 61 MPa strength.

MANGO (Mangifera indica L.) LEAVES WASTE/POLYVINYL ACETATE BIOCOMPOSITE FOR BUILDING MATERIALS APPLICATION

“…The strength of composite produced is very comparable to some materials mainly used in building materials application, such as sandstone stone (43 MPa), limestone (40 MPa), clay brick (20 MPa), aspen wood (36 MPa) and pinewood (41 MPa) (Brencich & Sterpi, 2006;Green et al, 2002;Nazir et al, 2013;Abouhussien et al, 2015). It means the composite is very potential to be used in a building application.…”

Effect of quartz sand on compressive strength of the solid waste composite

“…Additionally, the composite compressive strength of 40.47 MPa is also comparable and better than that to some building stones or woods widely used as material buildings, such as clay brick (~20.2 MPa) [27], slate stone (~ 61 MPa) [28], sandstone (~ 43 MPa) [29], limestone (~ 39 MPa) [30], alder wood (~ 40.10 MPa), aspen wood (~ 36.5 MPa), black cherry wood (~ 49.60 MPa) and pine wood (~ 41.90 MPa) [31] . It shows that the composite produced is very prospective to compete some building materials.…”

Detection of Abrasion Damage in Self-Consolidating Concrete Using Acoustic Emission Monitoring

“…Self-consolidating concrete (SCC) is a highly workable concrete intended for use in heavily reinforced or hard-to-reach areas [1][2][3][4][5]. SCC can be produced through the use of chemical admixtures to reduce the water content, decreasing the proportions of coarse aggregate in the mixture and/or incorporating supplementary cementing materials (SCMs) such as fly ash, silica fume, metakaolin, and/or natural pozzolans [6][7][8][9][10].…”