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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.

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.

This paper investigates the effect of using wastes sawdust as a replacement of fine aggregate (sand) on mechanical properties naming compressive, tensile and flexural strengths of ordinary Portland concrete. The wastes sawdust was treated before incorporating it in concrete mixtures. Three different methods were used to pre-treat the sawdust including a) soaking the sawdust in distilled water at 50 oC, b) soaking the sawdust in Ca (OH)2 solution, and c) soaking the sawdust in Ca (OH)2 solution and using a set accelerator in the concrete mixture. In addition to the control mixture (having no sawdust), three more concrete mixtures were prepared to explore the effect of the three different methods of pre-treatment on the mechanical properties of concrete. Results showed that the compressive strength of the concrete incorporating wastes sawdust pre-treated with the calcium hydroxide solution (slaked lime) and having the accelerator was higher than that of the control mixture. The tensile and flexural strengths of the concrete mixture having waste sawdust pre-treated by Ca (OH)2 solution and having the accelerator were found to be very comparable to those of the control mixture. On the other hand, the compressive, tensile, and flexural strengths of the concrete mixture with sawdust pre-treated by Ca (OH)2 solution only were somehow comparable to those of concrete mixture having sawdust pre-treated by distilled water. While the compressive strength of the concrete mixtures incorporating sawdust pre-treated with either Ca (OH)2 solution or distilled water was less than that of the control mixture, both tensile and flexural strengths of the two treated concrete mixtures were approximately comparable to those of the control mixture.

The need for sustainable concrete with low carbon dioxide emissions and exceptional performance has recently increased in the building industry. Many distinct types of industrial byproducts and ecologically safe wastes have shown promise as ingredients for this kind of concrete. Meanwhile, as industrialization and lifestyle modernization continue to rise, ceramic waste becomes an increasingly serious threat to the natural environment. It is well known that free cement binder that incorporates tile ceramic wastes (TCWs) can significantly improve the material’s sustainability. We used this information to create a variety of geopolymer mortars by mixing TCWs with varied proportions of ground blast furnace slag (GBFS) and fly ash (FA). Analytical techniques were used to evaluate the mechanical properties and impact resistance (IR) of each designed mixture. TCWs were substituted for binders at percentages between 50 and 70 percent, and the resultant mixes were strong enough for real-world usage. Evidence suggests that the IR and ductility of the proposed mortars might be greatly improved by the addition of TCWs to a geopolymer matrix. It was found that there is a trend for both initial and failure impact energy to increase with increasing TCWs and FA content in the matrix. The results show that the raising of TCWs from 0% to 50, 60 and 70% significantly led to an increase in the failure impact energy from 397.3 J to 456.8, 496.6 and 595.9 J, respectively.

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