Strength and permeability properties of self-compacting concrete with cold bonded fly ash lightweight aggregate

• Cold bonded fly ash lightweight aggregates (LWA) were manufactured by pelletization.
• SCC with partial replacement of LWA with natural aggregate were produced.
• Binary and ternary blends of fly ash (FA) and silica fume (SF) were utilized for SCC.
• Compressive strength and some permeability properties were tested at different ages.
• Significant enhancement levels were observed depending on the mix compositions.

This paper presents the results of an experimental study on the hardened characteristics of the self-compacting concretes made with cold bond fly ash lightweight aggregates. Binary and ternary use of fly ash (FA) and silica fume (SF) blends have been considered in the production of self-compacting cold bonded fly ash lightweight aggregate concretes (SCLWCs). For this, a total of 9 SCLWC mixtures were proportioned having constant water–binder ratio of 0.35 and the total binder content of 550 kg/m3. The control mixture contained only Portland cement (PC) as the binder while the remaining mixtures having binary and ternary blends of PC, FA, and SF. Properties that include compressive strength and ultrasonic pulse velocity, chloride ion penetration, gas permeability, water absorption by total immersion and by capillary absorption were investigated at two curing ages of 28 and 56 days. Test results have showed that incorporating the mineral admixtures enhanced significantly the permeability characteristics. Moreover, it was observed that the compressive strength of the SCLWCs with SF was much higher than those of the control concrete.