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The disposal of ceramic tile waste poses a significant environmental challenge in the construction industry. This study aims to explore the influence of calcium carbonate (CC) on the properties of self-compacting concrete (SCC) incorporating porcelain tile waste as a coarse aggregate replacement. The objective is to enhance the performance of SCC while addressing the limitations of recycled ceramic aggregates and achieving the desired strength class. SCC specimens were cast by partially and completely substituting natural crushed rock with varying percentages of porcelain tile aggregates (PTA-0, 25 %, 50 %, 75 %, and 100 %) and cement with calcium carbonate (CC-10 %, 20 %, and 30 %). Workability assessments, mechanical properties, and durability were evaluated and compared against those of reference concrete. The experimental findings revealed that the incorporation of CC and PTA positively influenced the workability, mechanical properties and durability of SCC. Notably, the SCC mixture incorporating 10 %CC and 25 %PTA demonstrated exceptional performance, achieving the highest compressive strength of 64.9 MPa at 28 days. Moreover, even with complete substitution, the compressive strength reduction remained below 5 %. These results highlight the potential of PTA and CC-based SCC mixtures as an efficient and sustainable approach for utilizing porcelain tile waste in high performance concrete production. The findings contribute to addressing environmental concerns, promoting waste management practices, and reducing the reliance on natural resources in the construction industry.

In this work, the effects of recycled concrete aggregate, modified with mineral admixtures and nanosilica, on the mechanical properties and performance of concrete after curing in tap water for 28 and 90 days were investigated. The compressive (ƒc), indirect tensile (ƒt), and flexural (ƒb) strengths for the cured concrete specimens were measured, and the concrete strength ratios were analyzed. The water and rapid chloride permeabilities were measured. SEM analysis of the microstructure was also performed. The coarse aggregates used were dolomite (control) and recycled concrete aggregate, incorporating different mineral admixtures, including ground, granulated blast slag, granite, and nanosilica. It was found that the slump values of the dolomite concrete decreased compared with recycled aggregate concrete. Compared to the control mix produced with the recycled aggregate, the slump value of the concrete mixes created with the recycled aggregate increased by approximately 11.1% with the addition of binary cementing materials of 1% NS. The results also indicate that the concrete mix containing the recycled aggregate had the highest compressive strength, tensile strength, and flexural strength compared to that of the dolomite aggregate. Regarding the compressive strength, the addition of 1% NS and 15% slag improved the physico-mechanical properties of the recycled aggregate concretes compared to the other mixes after curing in tap water. Compared to the other mixes, the concrete mix containing 1% NS and 15% slag had a comparatively dense and compact microstructure. [ABSTRACT FROM AUTHOR]

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This study offers numerical simulation results using the ABAQUS/CAE version 2019 finite element computer application to examine the performance, and residual strength of eight recycle aggregate RC one-way slabs. Six strengthened by NSM CFRP plates were presented to study the impact of several parameters on their structural behavior. The experimental results of four selected slabs under monotonic load, plus one slab under repeated load, were validated numerically. Then the numerical analysis was extended to different parameters investigation, such as the impact of added CFRP length on ultimate load capacity and load-deflection response and the impact of concrete compressive strength value on the structural performance of slabs. This article aims to provide a numerical model for simulating the nonlinear behavior of such slabs, including a trustworthy finite element model approach and constitutive material models. In aspects of load-deflection and cracking patterns, comparisons between computational and experimental models are provided, and a reasonable fit is demonstrated. The average ratio of numerical model ultimate load and deflections to experimentally tested slabs were 0.992 and 0.913, respectively. As a result, finite element analysis may be regarded as a preferred and trustworthy approach for simulating the non-linear behavior of one-way slabs (strengthened or not) in terms of complexity, difficulty, time savings, human effort, and money.

In this work, the effects of recycled concrete aggregate, modified with mineral admixtures and nanosilica, on the mechanical properties and performance of concrete after curing in tap water for 28 and 90 days were investigated. The compressive (ƒc), indirect tensile (ƒt), and flexural (ƒb) strengths for the cured concrete specimens were measured, and the concrete strength ratios were analyzed. The water and rapid chloride permeabilities were measured. SEM analysis of the microstructure was also performed. The coarse aggregates used were dolomite (control) and recycled concrete aggregate, incorporating different mineral admixtures, including ground, granulated blast slag, granite, and nanosilica. It was found that the slump values of the dolomite concrete decreased compared with recycled aggregate concrete. Compared to the control mix produced with the recycled aggregate, the slump value of the concrete mixes created with the recycled aggregate increased by approximately 11.1% with the addition of binary cementing materials of 1% NS. The results also indicate that the concrete mix containing the recycled aggregate had the highest compressive strength, tensile strength, and flexural strength compared to that of the dolomite aggregate. Regarding the compressive strength, the addition of 1% NS and 15% slag improved the physico-mechanical properties of the recycled aggregate concretes compared to the other mixes after curing in tap water. Compared to the other mixes, the concrete mix containing 1% NS and 15% slag had a comparatively dense and compact microstructure.

Huge volume of recycled aggregates are produced annually, in the economic and environmental view, they need to consume in the appropriate section of the construction industry. In this paper, a recycled aggregate has been used for seismic modeling of embankment-subsoil. The nonlinear software was employed in the modeling. For assessment modulus elasticity and lateral displacement of the model, the mechanical properties of the soil and the recycle aggregates designing have been selected as parameters. Three models, with the same geometry and different type of materials, have been configured. Results revealed the recycle aggregate enhances seismic mitigation of the model. The outcome of this study demonstrated using recycled aggregate in the construction industry impacts on (i) control strain and stress directions, (ii) minimize lateral displacement of the model, (iii) enhance modulus elasticity of the embankment-subsoil model, and (iv) the seismic stability of the embankment-subsoil model. The statistical analysis showed, the high accuracy for interpreting modulus elasticity of the model, and it is good evidence for numerical analysis accuracy results.