Across the world, a huge amount of waste materials is deposited from different industrial or construction activities. Out of this massive waste quantity, a petite is recycled and remaining is dumped in vulnerable lands. This paper deals with the potential utilization of solid waste in reactive powder concrete, practically powdered glass originating from waste glass bottles and powdered ceramics tile from waste of construction process. First, the optimum ratio of waste pozzolanic material (ceramics to glass ratio) was obtained by pozzolinic activity test. Then, the optimal waste pozzolanic material was incorporated in reactive powder concrete at several substitution levels. The waste pozzolanic material in 5 %, 10 %, 15 %, 20 %, and 25 % were added in the reactive powder concrete mixes as fractional supplement of silica fume. Strength and water absorption of the modified reactive powder concrete were evaluated. A significant enhancement was observed in mechanical behavior of modified reactive powder concrete containing 15 % waste pozzolanic material. Results directed irrelevant raise in water absorption as increasing the waste replacement material.

The aim of current experimental research is to examine the performance of the Reactive Powder Concrete modified by Pulverized Local Wastes materials. In this research, Reactive Powder Concrete was adapted by using local wastes (finely crushed ceramic tiles wastes) with Portland cement, silica fume, water, and chemical admixture through partially replacement of fine sand for sustainable practice in construction. This study exploited normal curing process at ambient temperatures as an alternative of higher temperatures steam curing for sustainability of construction works. To assess the behavior of the modified Sustainable Reactive Powder Concrete mixes, splitting and compressive strengths of Reactive Powder Concrete were inspected experimentally, and then associated with traditional Reactive Powder Concrete mix (the control mix). Furthermore, the hardened density of the modified Sustainable Reactive Powder Concrete was checked. The inquiry results directed that substituting the fine sand partially by Pulverized Local Wastes (finely crushed ceramic tiles wastes) is an adequate method for construction applications. Consequently, the compressive strength and spilling strength of modified Sustainable Reactive Powder were maintained by using 10 % of finely crushed ceramic tiles wastes. Results illustrate that Reactive Powder Concrete have an insignificant strength loss with 10 % sand replacement for compressive strength and splitting strength. The reduction percent in the compressive strength and splitting strength at 28 days are 12.37% and 8.55%, respectively, linked with related control mix.

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Composite concrete Filled Tubular Steel (CFT) members, which have excellent deformability due to the well-known confined and constrained interaction between steel tube and concrete, have largely been utilized as bridge piers or columns in high-rise buildings, resulting in increased strength and decreased column size. This study examined the experimental performance of steel tube columns filled with reactive powder concrete (RPC) under axial compression. Three sets of columns were used in the experiment, each with variations in shape (square, rectangular, and circular), length-to-diameter ratio, and compressive strength of the RPC. The first set consisted of five columns, while the second and third sets each had seven columns with three different lengths (750 mm, 600 mm, and 450 mm) and two different compressive strengths (54 and 92 MPa). A new numerical model was developed to calculate the ultimate failure load of the columns by considering factors such as the yield strength of steel, the compressive strength of concrete, the column shape, and the ratio of concrete to steel. This model was validated by comparing the results obtained from the experiments to those predicted by the model, as well as by designing equations from various codes. The results showed that the proposed numerical model accurately predicted the ultimate failure load for columns filled with different types of concrete, especially for RPC, while maintaining conservatism compared to the ACI, AISC, and EN codes equations. Doi: 10.28991/CEJ-2023-09-06-04 Full Text: PDF

This study investigates the accuracy of prediction normal concrete behavior in simulating punching shear strength of flat slab using finite element modelling in Abaqus. The Eurocode and FIB standards were adopted to predict concrete curves for compressive and tensile stresses, in addition to two models adopted in this study based on preview expereimental stuies. Then punching shear strength of two selected flat slab specimens (with and without studs) were simulated in Abaqus to validate punching shear force vs vertical midspan displacement for the adopted experimental work. Simulation results have shown very good results in comparison to the finite element analysis (FEA) curves. Also, the test results have showed that a comparable result with various codes models (ACI-318, BS-8110, EC2, and CEB FIB model code 90).