Effect of Expanded Perlite Aggregate Dosage on Properties of Lightweight Concrete

Abstract

In this paper, an experimental study was carried out in order to provide more data on the effects of expanded perlite aggregate (EPA) dosage on the compressive strength and thermophysical properties of lightweight concrete at different ages. The first part of this experimental study was devoted to the choice of the proper mixing procedure for expanded perlite concrete (EPC). Thereafter, six sets of cubic specimens and six sets of parallelepiped specimens were prepared at a water-to-cement ratio of 0.70 with varying replacement percentages of sand by EPA ranging from 0% to 80% by volume of sand. Compressive strength, thermal conductivity and thermal diffusivity were determined over curing age. Unit weights for the mixtures prepared varied between 560 and 1510 kg/mP 3 P. Compressive strength was decreased when perlite content was increased. The test results indicated that replacing natural aggregate by EPA increased the thermal resistance of the lightweight concrete and consequently, improved thermal insulation.

Experimental Study of New Insulation Lightweight Concrete Block Floor Based on Perlite Aggregate, Natural Sand, and Sand Obtained from Marble Waste

“…e e ective water/cement ratio (W/C) was equal to 0.70 and was kept constant in all mixtures. e percentage of EPA was chosen to be constant (45%) in order to guarantee a suffusing resistance of specimens [5]. Table 5 gives the composition of all prepared mixtures.…”

“…e results illustrated in Figure 4 show that the incorporation of SWM in the di erent mixtures did not change the type of concrete. Indeed, it is always a lightweight concrete since the values of unit weight varies between 560 kg/m 3 and 1500 kg/m 3 [5]. is is due to EPA, which represents 45% of the concrete volume with a density of the order of 70 kg/m 3 .…”

“…is is due to the density values of these concretes, which are considered high compared to other lightweight concretes classi ed as highly insulating. For example, according to Reference [5], the thermal conductivity of autoclaved aerated concrete is approximately 0.33 W/mK for a density of 770 kg/m 3 .…”

“…To calculate the thermal di usivity, we used the approximate method presented by using the Degiovanni model based on the method of partial time [5,28,29]. e thermal di usivity of the sample is given as follows [29]: Advances in Materials Science and Engineering where e is the specimen thickness and t 1/3 , t 1/2 , t 2/3 , and t 5/6 are, respectively, the partial times for 1/3, 1/2, 2/3, and 5/6 of the maximum value of the temperature (Figure 10).…”

“…Recycling and waste recovery are now considered as a solution for future in order to meet the deficit between production and consumption and to protect the environment [4]. When adding EPA aggregate to the granular matrix, we obtain ordinary concrete, lightweight concrete [5], fire-resistant concrete [6], or insulating concrete. In addition, some research shows that perlite can be used as an aggregate in Portland cement and gypsum plasters for exterior applications [7].…”