Journal of Ceramics and Concrete Sciences (e-ISSN: 2582-1938) (p-ISSN: 3049-0626)

Benchmark-Informed Technical Assessment of an M60 Concrete Matrix with Untreated and Pozzolanic-Slurry-Treated Recycled Coarse Aggregate

Suhasini Pasi, Guru Sharan Mishra — Mon, 21 Sep 2026 00:00:00 +0000

This technical paper develops a reproducible M60 high-performance concrete programme using untreated and pozzolanic-slurry-treated Recycled Coarse Aggregate (RCA) and evaluates the proposed decision gates against an external benchmark. The nine-mixture matrix comprises a natural-aggregate control (N0), untreated RCA at 25%, 50%, 75%, and 100% replacement (U25–U100), and corresponding treated mixtures (T25–T100). Binder content is fixed at 500 kg/m³ with 10% silica fume, free water is 160 kg/m³, and the water-binder ratio is 0.32. Treatment uses a 70:30 fly-ash solids blend, a 1:1 water-to-solids ratio, 3 min dispersion, and 4 h immersion. Because verified specimen-level results for the proposed N0/U/T matrix are not yet available, published matched natural- and recycled-aggregate self-compacting-concrete data are analyzed only as an external benchmark and are not presented as results of the proposed matrix. Complete fine-plus-coarse aggregate replacement reduced slump flow by 6.1%–9.2%. At 28 days, recycled-to-natural retention was 76.1%–80.3% for compression, 76.4%–80.9% for splitting tensile strength, and 77.9%–82.0% for flexure. Both aggregate families continued to gain strength through 91 days, but the relative gap persisted; the strongest recycled benchmark mixture reached 53.94 MPa at 28 days and 64.97 MPa at 91 days. These findings support a non-compensatory decision rule in which M60 compression, tensile retention, transport durability, carbonation, shrinkage, and chemical resistance must be satisfied before GWP, resource saving, embodied energy, and cost are ranked. The paper provides the experimental matrix, treatment controls, equations, graphs, acceptance gates, and reporting template required for future specimen-level validation.

Experimental Investigation of Prestressed Concrete Beams Strengthened with Fiber-Reinforced Polymer Laminates

Karasala Mastan Rao, Nayab Mahaboobsubhani, Naga Sowjanya Pongunuru — Tue, 04 Aug 2026 00:00:00 +0000

This study evaluates the effectiveness of externally bonded glass fibre-reinforced polymer (GFRP) laminates in improving the static performance of pre-stressed concrete beams. Fourteen post-tensioned concrete beams were fabricated and tested under progressively applied static loading, with two unstrengthened beams serving as control specimens and the remaining beams strengthened using various GFRP laminate configurations. The experimental program included beams cast with M35 and M60 concrete grades and reinforced using Chopped Strand Mat (CSM), Woven Roving (WR), and Uni-directional Cloth (UDC) laminates with different thicknesses. The influence of concrete strength, laminate type, and laminate thickness on structural performance was assessed by examining yield load, deflection, ductility, energy absorption, and failure characteristics. The findings demonstrated that the application of GFRP laminates substantially enhanced the load-carrying capacity, flexural stiffness, and ductility of the strengthened beams compared with the control specimens. In addition, Finite Element Method (FEM) simulations closely replicated the experimental results, confirming the reliability of the numerical model. Regression-based predictive equations were also developed to estimate the key structural performance parameters, providing a practical tool for the analysis and design of GFRP-strengthened pre-stressed concrete beams.

Evaluation of Pervious Concrete Pavement for Phreatic Groundwater Recharge

Ravi Kumar R, Meghana C. S., Chandana C., Darshan R. — Thu, 08 Oct 2026 00:00:00 +0000

The amount of impervious surfaces associated with urban development has increased, altering the natural flow of rainwater and reducing the amount of rainfall that can infiltrate into the ground. Concrete and bituminous roads also tend to direct much of the rainfall into the drainage system, thereby increasing surface runoff and reducing groundwater recharge. Pervious concrete pavement is an alternative approach where interconnected voids in the concrete allow water to flow through the pavement structure. This study investigates the possibility of pervious concrete pavement to improve infiltration and to contribute to the recharge of the phreatic zone. The main difference between pervious concrete and conventional concrete is the open-graded aggregate structure and limited or no use of fine aggregate. Thus, this network of interconnected pores provides a conduit for water movement through the pavement. Previous experimental studies have shown that the hydraulic performance of pervious concrete is greatly influenced by aggregate size, cement content, water-to-cement ratio, compaction, and void content. Field investigation of pervious concrete pavement in Ahmedabad indicated successful drainage and evaluated its strength, void ratio, permeability, and infiltration performance. The proposed method treats the pavement, granular sub-base, and underlying soil as an integrated infiltration system. Field studies of two-layer pervious concrete pavement systems have shown water infiltration through both the pervious concrete and the granular sub-base. Therefore, selecting the right pavement mix and sub-base is important to achieve sufficient permeability without sacrificing the required structural performance. The proposed system has the potential to reduce surface runoff, improve stormwater management, and provide an opportunity for groundwater recharge where site conditions permit.

Experimental and Finite Element (ANSYS)-Based Evaluation of the Axial Compressive Behavior of CFRP-Confined Reinforced Concrete Members

Thu, 10 Sep 2026 00:00:00 +0000

Reinforced Concrete (RC) members strengthened with externally bonded Carbon Fiber Reinforced Polymer (CFRP) fabric offer a lightweight, corrosion-resistant alternative to conventional jacketing. This study presents a combined experimental and nonlinear finite-element investigation of the axial compressive behavior of CFRP-confined RC cylindrical members. Six specimens (150 mm diameter × 300 mm height), cast in M20-grade concrete with Fe500 reinforcement, were divided equally into unwrapped control and CFRP-wrapped groups and tested to failure under a Compression Testing Machine (CTM). CFRP confinement increased the average ultimate load from 558.47 to 632.3 kN (13.2% enhancement) and raised compressive strength from 31.62 to 35.80 MPa, while axial deformation capacity improved by 44.4%, reflecting a marked gain in ductility and energy absorption. Control specimens failed abruptly through vertical splitting and spalling, whereas CFRP-wrapped specimens exhibited delayed cracking and a gradual, ductile failure governed by fabric rupture or debonding. A companion nonlinear finite element model, built in ANSYS Workbench using SOLID186 elements with a bonded CFRP concrete interface, reproduced the experimental trend: the predicted ultimate load rose from 527.53 to 568.78 kN (7.82% increase), and the maximum principal stress increased from 3.77 to 5.75 MPa. Comparison of experimental and numerical ultimate loads showed deviations of 5.5% and 10.0% for the unwrapped and wrapped configurations, respectively, confirming that the calibrated model captures the governing confinement mechanics while slightly overestimating stiffness owing to the idealized bond assumption. The results substantiate CFRP wrapping as an effective, code-complementary retrofitting strategy for axially loaded RC members and demonstrate that validated ANSYS simulation can reliably support design-stage prediction of confined member response.