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One reason why concrete is a successful and commonly used building material is that it can be cast into any structural form required, taking advantage of its fluid behaviour at early ages. However, there is a limit to the fluid behaviour of normal fresh concrete, which cannot, on its own, flow past obstructions, through nooks or into corners. Thorough compaction, using vibration, is normally essential for achieving the required strength and durability of concrete. As concrete is produced and placed at construction sites, under conditions far from ideal, it often ends up with unpleasant results such as rock pockets, sand streaks, and a host of workmanship-related problems. The costs of remediation and making good may be high, or the durability may be compromised. Self-compacting concrete (SCC) may provide a solution to these problems. As the name signifies, it is able to compact itself without any additional vibrations or compactive effort. Consequently the danger of vibration- and noise-related health issues is minimised, and the construction process is safer and more productive. There have been several studies of SCC and the use of admixtures in it. Of these, the partial replacement of sand with ground granulated blastfurnace slag has gained considerable impetus. The main objective of this paper is to investigate the effect of maximum size of aggregate on the fresh and hardened properties of SCC. The behaviour of various mix proportions of SCC was investigated, and the variations in the compressive strength and split tensile strength of standard cubes and cylinders were studied. Ultrasonic pulse velocity was also studied to assess the quality of SCC with different maximum sizes of aggregates.

The lubricants employed at the die/billet interface reduce the adhesion and improve the formability of the AA 2014-T6 billets by avoiding cracks. The friction factor obtained from the ring compression test for different lubricants was correlated with the hypothesis of ductile fracture based on void failures to examine the damage rate with the increasing strain. Mohr–Coulomb criterion was employed for observing the cohesive failure for different aluminum alloys. The fitting parameters in the Mohr–Coulomb criterion were varied to study the influence of the process parameters on the fracture strain. The hardness variation in the billets for different stress triaxialities and Lode parameters was also investigated by constitutive modeling of the hardness with the equivalent strain.

The present study is aimed to study the effect of elevated temperatures ranging from 50 to 250°C on the compressive strength of high-strength concrete (HSC) of M60 grade made with ordinary portland cement (OPC) and pozzolona Portland cement (PPC). Tests were conducted on 100 mm cube specimens. The specimens were heated to different temperatures of 50, 100, 150, 200 and 250°C for three different exposure durations of 1, 2 and 3 h at each temperature. The rate of heating was maintained as per ISO-834 temperature–time curve for standard fire. After the heat treatment, the specimens were tested for compressive strengths. Test results were analysed and the effects of elevated temperatures on PPC concrete were compared with OPC concrete. The PPC concrete exhibited better performance than OPC concrete.

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