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Wood yields a number of by-products and Sawdust is as useful as others. Sawdust is regarded as a waste material and is effectively utilised as sawdust concrete in the construction of buildings. It is capable to be utilised as light-weight concrete and holds the quality of long duration heat transfer. In this study, three different ratios (1:1, 1:2 and 1:3) volume mix proportions of cement to sawdust were adopted to make sawdust concrete. At varied intervals of 7, 28 and 56 days of air curing, thermal and mechanical properties like workability, density, elastic modulus, strength and heat transfer were probed of mentioned sawdust concrete proportions. The resistance to elevated temperatures was also evaluated after 28 days of age; weight loss, residual compressive strength, surface texture and ultrasonic pulse velocity were considered in evaluation process. The findings showed that increase in sawdust volume affected to decrease the workability, strength and elevated temperatures resistance. However, the concrete having higher proportion of sawdust performed competently and well in terms of thermal conductivity. Moreover, a decrease in the heat transfer of sawdust was also observed. Examining the all-embracing mechanical and physical properties, sawdust can be effectively utilised in the construction of buildings.

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The effect of out plane dynamic loading on the reinforced concrete slab is evaluated in order to estimate the impact resistance of reinforced concrete under low velocity impact loading. The experimental study is performed on M40 (f c ′ = 48 MPa) concrete slab specimen of size (1200 × 1200 × 50) mm reinforced with 6∅ mm Fe500 bars using pendulum drop weight (60 kg) impacting the center of specimen at a drop height of 370 mm. The impact velocity is calculated using open-source software as 2.7 m/s. The experimental study is evaluated for the impact force, crack pattern and the failure mode of the specimen. The peak force was observed as 36 kN from the experiment. The finite element analysis is performed using concrete damage plasticity (CDP) model available in ABAQUS to validate the model incorporating strain rate effects to accurately predict the behavior under dynamic loading. The constitutive model incorporating strain rate effects successfully predicted the behavior under impact loading and was quite beneficial contrary to the tedious experimental procedures. Overall, the results thus obtained from the finite element analysis found to be closely matching with the experimental results.

The flexural behavior of five reinforced concrete beams containing recycled ceramic as cement and aggregate replacement subjected to a monotonic static load up to failure was studied. A full-scale, four-point load test was conducted on these beams for 28 days. The experimental results were compared with the conventional concrete as a control specimen. The cross-section and effective span of these beams were (160 × 200 mm) and 2200 mm, respectively. The data recorded during the tests were the ultimate load at failure, steel-reinforcement bar strain, the strain of concrete, cracking history, and mode of failure. The beam containing 100% recycled aggregates displayed an ultimate load of up to 99% of the control beam specimen. In addition, the first crack load was almost similar for both specimens (about 14 kN). The deflection of the beam composed of 100% of the recycled aggregates was reduced by 43% compared to the control specimen. Regardless of the recycled ceramic aggregates ratio, quantities such as service, yield, and ultimate load of the proposed beams exhibited a comparable trend. It was asserted that the ceramic wastes might be of potential use in producing high-performance concrete needed by the structural industry. It might be an effective strategy to decrease the pressure on the environment, thus reducing the amount of natural resources usage.