Different structural lightweight concrete mixtures of specific density and strength classes were produced by using various lightweight aggregates (LWAs) such as pumice, perlite, and rice husk ash. Their properties were evaluated in fresh and hardened states with regards to compressive strength and durability parameters such as water absorption (open porosity and capillary absorption), chloride’s penetration resistance, and carbonation depth. According to the results, most LWA concrete mixtures performed satisfactorily in terms of the designed strength and density and they could be used as structural LWA concrete mixtures. As far as the durability of LWA concrete was concerned, open porosity and resistance to the carbonation of LWA concrete were burdened with the porous nature of LWAs, while sorptivity in some mixtures and especially chlorides’ penetration resistance in all mixtures were reported to be significantly improved. The overall strength and durability performance of the designed LWA concrete mixtures could mitigate the concerns stemming from its vulnerability to extreme exposure conditions.

In this paper, perlite mining and rice production by-products, namely run-of-mine perlite and rice husk ash, are used as fine aggregates in combination with pumice and calcareous aggregates to produce lightweight concrete. Their use is evaluated mainly in terms of the durability of the concrete, by comparing four optimized lightweight concrete mixtures of similar density and strength with a reference one of normal weight. The sorptivity due to capillary sorption, open porosity, chloride migration, penetration resistance, and freeze and thaw response were studied to evaluate the durability of the lightweight concrete. According to the experimental results, the examined mixtures developed an adequate strength in order to be classified into strength classes greater than LC25/28 and, therefore, be used in structural applications. The durability of the mixtures was also sufficient, especially as far as the chlorides’ penetration resistance is concerned, which was found to be up to 39% lower compared to the reference mixture. The sorptivity and open porosity of the LWC mixtures increased due to the porous nature of the lightweight aggregates, and the mixtures were also found to be susceptible to freeze and thaw cycles. Exceptionally, the lightweight concrete mixtures comprising pumice and perlite exhibited a lower sorptivity and resistance to chloride penetration than the standard concrete and a promising tolerance to freezing and thawing. Thus, the optimized combination of pumice and perlite is a sustainable recommendation for structural lightweight concrete production and use, promoting the wider exploitation of natural aggregates with an acceptable compromise on strength and durability.

The current research is aiming to investigate the chlorides’ penetration resistance of 9 different pumice lightweight aggregate mortars (LWAMs). The composition of the mixture is altered by the addition of metakaolin, fly ash, silica fume, and ground granulated blast furnace slag, substituting 10% and 20% of cement by mass. Workability and compressive strength of the mortars are studied together with durability parameters like water absorption due to capillary absorption and porosity. Moreover, the mortar resistance to chloride penetration is evaluated through non‐steady‐state chloride migration coefficient, complying to NT BUILD 492 standard. Summarizing all the laboratory test results, while the addition of metakaolin in the range of 20% led to better workability, higher compressive strength, lower sorptivity, and lower volume of open porosity, it did not improve the resistance against chlorides’ penetration.