International Journal of Structural Analysis and Advanced Construction Techniques

Low-Carbon Concrete in Bangladesh - A Comprehensive Review of Sustainable Materials and Practice

2026-08-11T06:35:33+00:00

The construction industry contributes to a large amount of carbon dioxide (CO₂) emissions, mostly because of the widespread use of ordinary Portland cement (OPC). Rapid urbanization and infrastructure development in Bangladesh have led to the growing demand for sustainable construction materials. The review describes the possibility of using low-carbon concrete (LCC) as an alternative to conventional concrete in order to reduce the impact of conventional concrete on the environment. The study covers the concept of LCC as per ACI 323-24 and investigates the feasibility of using locally available materials such as Fly ash, Ground granulated blast furnace slag (GGBFS), Rice husk ash (RHA), and recycled concrete aggregates (RCA). The effect of these materials on workability, mechanical, and durability properties is examined. The advantages of LCC are emphasized, including reduced greenhouse gas emissions, conservation of natural resources, and the use of industrial and agricultural by-products. The technical, regulatory, supply chain, and market acceptance challenges to the widespread adoption of LCC are also addressed. The review suggests practical strategies and local resources available in Bangladesh that can help in the large-scale adoption of LCC. The results show that LCC can be a significant contributor to the reduction of environmental impacts of the construction industry while providing acceptable engineering performance and fostering sustainable infrastructure development.

An Exploratory Structural Performance Index for Reinforced All-in Laterite Aggregate Concrete Beams Under Low Shear-Span-to-Depth-Ratio Loading

2026-09-07T05:10:29+00:00

All-in Laterite Aggregate Concrete (AILAC), in which both the coarse and the fine fractions are drawn from a single weathered laterite deposit, is a low-cost, locally available material for tropical regions, yet its shear behaviour has received little experimental attention. Because the shear strength, service stiffness and deformation capacity of a beam do not in general vary together, no single measured quantity ranks specimens on its own. This paper converts a small laboratory investigation of the shear behaviour of reinforced AILAC beams into an exploratory, within-sample Structural Performance Index (SPI). Four beams of 150 × 150 × 900 mm; three reinforced with 2Ø10, 2Ø12, and 2Ø16 mm tension bars (B_₁-10_, B_₂-12, and B_₃-16) and one plain beam (B_₄), one specimen per condition and without web reinforcement, were tested under symmetric two-point loading. With a shear span a = 150 mm and effective depth d ≈ 100 mm, the shear-span-to-depth ratio is a/d ≈ 1.5, placing the specimens in the short-beam / arch-action regime. Surface strains measured with 60° rosette gauges were reduced, under a pre-crack linear-elastic assumption, to principal strains, principal stresses, and the maximum shear stress; mid-span deflection tracked serviceability. The measured principal stress–strain response is strongly linear and indicates an effective elastic modulus of about 14 GPa and a shear modulus of about 5.8 GPa for the mix. The index combines three normalised, non-dimensional pillars: nominal shear strength, service-load secant stiffness, and ultimate deformation capacity, using a weighted geometric mean, chosen because it penalises imbalances among the pillars. Within the unreplicated series tested, the SPI ranks the beams B_₃-16 (0.93) > B_₁-10 (0.69) ≈ B_₂-12 (0.69) > B_₄ (0.20); the top and bottom ranks are stable across a range of weightings, while the two intermediate beams exchange places depending on the weights. Ultimate nominal shear strength increased with reinforcement ratio across the four specimens, and the principal-analysis shear stress rose with principal strain; an association that is expected, because the stress is computed from the strain through the assumed elastic relations, and is therefore reported as a descriptive consistency check rather than an independent result. Its ordering was consistent with the corresponding energy rankings and observed failure descriptions. The index should presently be interpreted as an exploratory within-sample decision aid; independent testing across laterite sources, reinforcement ratios, and shear-span-to-depth ratios is required before broader validation or design use.

Quantification of Fatigue-Influencing Factors in Critical Tubular Joints of Steel Jacket Offshore Structures in Gulf of Guinea Shallow Waters

2026-10-21T09:41:23+00:00

This study quantifies the key fatigue-influencing factors: hot-spot stresses, Stress Concentration Factors (SCFs), and fatigue damage ratios for six critical tubular joints (J1–J6) of a four-leg steel jacket platform operating in Gulf of Guinea shallow waters. Long-term metocean data were processed through global finite-element analysis and rainflow counting to extract nominal and hot-spot stress ranges under sea states ranging from m to 7.5 m. Parametric SCFs were verified and refined against detailed three-dimensional shell-element models of the most critical joints. Cumulative fatigue damage was evaluated using the Palmgren-Miner rule with the DNV D curve, and a probabilistic assessment based on Monte Carlo simulation was performed to account for uncertainties in metocean parameters, SCFs and S–N curve coefficients. Results show that the lower-bay wave-facing K-joint (J5) is the governing detail (FEA-refined SCF = 3.42, deterministic. , reliability index ). The splash-zone K-joint (J2) ranks second. Moderate sea states ( –4.5 m) contribute 49–56 % of total fatigue damage. The study establishes a reliability-based criticality ranking that provides operators with a transparent basis for prioritising inspection and life-extension interventions on Gulf of Guinea jackets. This is the first assessment that combines FEA-refined SCFs with a full probabilistic treatment of tropical metocean uncertainties for a GoG jacket structure.

Comparative Structural Analysis of Conventional Beam-Slab System and Flat Slab with Drop Panels Using ETABS

2026-10-21T10:19:19+00:00

The choice of floor system strongly affects the structural efficiency, clear headroom, and construction economy of multi-storey buildings. The conventional beam-slab system is stiff but limits architectural flexibility and the routing of services, whereas flat slabs remove the beams and speed up construction but are prone to larger deflections, which drop panels around the columns are used to reduce. This paper compares a conventional beam-slab system with a flat slab with drop panels in a 10-storey residential building modeled in ETABS. Both models have identical geometry (20.0 m × 20.0 m plan, 5.0 m grid, 3.0 m storey height), materials (f′c = 25 MPa, fy = 500 MPa), column sizes, loads, and supports, and were analyzed under gravity loading. The maximum vertical deflection at the critical top-floor mid-span fell from −6.00 mm in the beam-slab model to −4.10 mm in the flat slab model, a reduction of about 31.7%. The total dead load base reaction was 30,093.44 kN for the beam-slab model and 29,031.44 kN for the flat slab model (3.53% lower), while the live load reaction was identical at 12,000.00 kN. The results indicate that drop panels can provide adequate serviceability without down stand beams under the gravity loading considered. The findings may help engineers select a suitable floor system, although lateral loading, punching shear, and cost were outside the scope of this study.

A Study on Cloud Computing and Project Management in Construction

2026-10-29T05:09:23+00:00

Construction projects bring together many parties and large volumes of information, yet much of that information is still held in separate, often paper-based systems. This paper reviews how advanced computing, particularly cloud computing, is being used to address challenges in construction project management. It examines literature published between 2010 and 2022 on Building Information Modelling (BIM), cloud-based applications, and digital quality management. The discussion focuses on the role of these technologies in improving collaboration, information sharing, project coordination, and overall construction management efficiency. The reviewed work indicates that cloud applications such as Google Apps, Autodesk BIM 360 and Viewpoint offer the widest range of functions for the built environment, and that organising project information into shared, linked views can reduce fragmented working practices. The studies also agree that technology alone is not enough: project management processes, tools and the skills of project participants must change alongside it, and open standards are needed so that information can pass between software from different vendors. The paper concludes that cloud-enabled, BIM-based platforms are a promising basis for a more unified approach to project management, and that interoperability, data security and the use of artificial intelligence and big-data analytics are the main directions for future research.