Lightweight Reactive Powder Concrete Containing Expanded Perlite

Abstract

This paper presents the test results of the lightweight concrete properties obtained by adding expanded perlite (EP) to an RPC mix in quantities from 30% to 60% by volume of the concrete mix. It has been shown that in these cases it is possible to obtain concrete containing 30% by volume with density of approximately 1900 kg/m3 and the compressive strength > 70 MPa, with a very low water absorption value (3.3%), equal to the water absorption value of RPC without lightweight aggregate (3.3%). However, with the increased quantity of perlite (from 45% to 60%), the concrete density reduction is not observed, as the expanded perlite demonstrates very low resistance to crushing. With the increased amount of perlite, the longer periods of mixing time for all the mix components are required to obtain the homogeneous and fluid concrete mix, what causes grounding down EP. Therefore, using larger quantities of this aggregate in RPC is not recommended. The lightweight RPC shows very good freeze-thaw resistance in the presence of de-icing salt (the scaling mass is lower than 0.1 kg/m2). The above is explained by the compact microstructure of this concrete and the RPC mix location in open pores on the perlite aggregate surface, which consequently affects the strengthening of the aggregate-matrix contact without an interfacial transition zone (ITZ) visible. It has been demonstrated that pozzolanic activity of expanded perlite is much lower than the activity of silica fume and quartz powder, and its impact on increasing the RPC strength is minimal.

Modelling the Influence of Composition on the Properties of Lightweight Plaster Mortar and Multicriteria Optimisation

“…The effect of perlite on strength can be explained by the formation of close particle packing and the creation of strong monolithic films. Furthermore, the pozzolanic reaction between perlite and calcium hydroxide can take place, which could lead to the increasing of durability [ 64 , 65 ]. The perlite sand increases mixed thixotropy as well; this can be seen from Table 6 , where b 2 = 84.3.…”

Properties of Fine Graded Perlite-Based Lightweight Cement Mortars Subjected to Elevated Temperatures

“…The strength of the cement-aggregate composite is a function of the strength of the cement matrix, the strength of the aggregate and the bond between these phases [82]. In case of heating in the studied range, the sand and perlite generally remain unchanged [26,83]. Changes are present in the cement matrix.…”

“…It also possesses one of the lowest densities among other lightweight materials suitable for aggregate use [22], and it has the potential to effect internal self-curing in cement composites due to its water retention abilities [23,24]. It is manufactured by grinding and firing natural rock at 800-1200 • C. Under these conditions, the rock softens and the water in it turns into steam and causes expansion [25,26]. Perlite rock is an amorphous material which consists mainly of silicon dioxide [26].…”

“…It is manufactured by grinding and firing natural rock at 800-1200 • C. Under these conditions, the rock softens and the water in it turns into steam and causes expansion [25,26]. Perlite rock is an amorphous material which consists mainly of silicon dioxide [26]. Expanded perlite is used alone as a granular thermal insulation material.…”

Preparation and Compression Resistance of Lightweight Concrete Filled with Lightweight Calcium Carbonate Reinforced Expanded Polystyrene Foam

“…At present, fillers for lightweight concrete mainly include expanded perlite [ 14 , 15 ], foam particles (such as polystyrene foam balls [ 16 , 17 ], ceramic balls [ 18 , 19 ], and so on), and expanded clay [ 20 , 21 ]. Stefania Grzeszczyk et al [ 22 ] added expanded perlite to concrete to obtain lightweight concrete. Test results showed that the density of lightweight concrete was 1900 kg/m 3 , and the compressive strength was >70 MPa when filled with 30 vol% expanded perlites.…”