This study was carried out to determine the characterization of brown coir fiber which is used as a potential reinforcement in polymer composites. The fiber is extracted from the husk of the coconut seeds which are collected in Sri Lanka. Anyhow the above-mentioned characterization can hardly be...

The construction sector faces increasing pressure to reduce the embodied energy of building materials while valorizing industrial waste streams. This study evaluates the direct incorporation of post-industrial textile waste (100% cotton and cotton–polyester blends) in its native form to develop high-performance cementitious ceiling sheets. Composites were fabricated under a controlled hydraulic compaction pressure of 2.0 MPa, optimized to achieve matrix densification while preserving the integrity of the fibrous network. Viscoelastic recovery of the compressed fibers induced a hierarchical double-porosity architecture characterized by macro-voids and hollow fiber lumens. This microstructural evolution reduced thermal conductivity to 0.091 W/m·K, approximately 50% lower than commercial cement–fiber benchmarks—without compromising mechanical compliance. Scanning Electron Microscopy (SEM) revealed a mechanistic decoupling between water absorption and dimensional stability. Although the CP15 formulation (15 wt.% cotton–polyester) exhibited high moisture uptake (~21%), thickness swelling remained limited to 1.35%. This dimensional stability is attributed to the hydrophobic polyester framework, which bridges microcracks and constrains hygroscopic expansion within the cellulosic phase. The optimized CP15 composite achieved a Modulus of Rupture (MOR) of 8.75 MPa, exceeding ISO 8336 Category C, Class 2 requirements. Despite increased thickness, the areal density (10.84 kg/m²) remains compatible with standard gypsum-grade suspension systems, eliminating the need for structural modification. These findings establish a scalable, direct-valorization strategy for circular construction materials delivering enhanced thermal insulation and robust performance under tropical climatic conditions.

The inherent nature of construction projects is long duration and high cost. Extended project duration leads to escalation of cost. If the project duration is too long, the initial estimation may not be sufficient to recover the actual cost of the contract. To address this problem, Construction Industry Development Authority (CIDA) has introduced a price adjustment method called the “ICTAD formula method for adjustments to contract price due to fluctuation in prices”. Contract documents related to construction projects also provide some provisions to address the issues with material price fluctuations. This study investigated the practices of contractors to minimize the effect of price variation and support of price fluctuation clauses to minimize the impact of price variation. A questionnaire survey was conducted among the professionals to represent CS2 to C5 grade construction companies registered at CIDA. The questionnaire consisted of practices of contractors to minimize the effect of price variation and the impact of using price fluctuation clauses in different aspects. Collected responses were converted to a quantitative value using the relative importance index (RII). In addition, SPSS software was used for the critical review of responses. The results revealed that contractors mostly agree with using price fluctuation clauses to recover the increased project cost due to increased construction input prices. Further, results are evident that using price fluctuation clauses helps to fair risk sharing between the contractor and the client.

This study evaluates the feasibility of using waste polyethylene as a construction material. To achieve this, a series of polymer composites were developed using waste Low-Density Polyethylene (LDPE) reinforced with coconut fiber (coir). The mechanical properties, including the tensile strength, flexural strength, impact strength, and elastic modulus, were assessed, along with the water absorption as a key physical property by following the ASTM standards. The composites were fabricated using the hand layup technique with varying coir-to-LDPE weight ratios and fiber lengths, followed by a hot-press machine manufacturing under controlled conditions. The results demonstrated that different fiber lengths and content levels influenced the mechanical properties, optimizing them at various configurations. A maximum tensile strength of 12.56 MPa was achieved using 40% coir content with 4 cm fiber length. The highest elastic modulus value of 0.46 GPa was achieved at 50% fiber content with 4 cm fibers. At 30% fiber content with 3 cm length, the maximum flexural strength value of 33.77 MPa was obtained. The impact strength reached its maximum value of 1.22 kJ/m² with 40% fiber content and 2 cm fiber length. The high water absorption exhibited by the composites, can be mitigated by applying waterproofing chemicals immediately after fabrication. It was found that the integration of fiber content and length affects the composite's properties. Depending on the required characteristics, appropriate fiber lengths and mix proportions can be selected, making these composites suitable for various applications in the construction industry. Additionally, proper waterproofing immediately after manufacturing the composite is proposed to enhance its performance as a construction material.

Environmental concerns and economic crises have been more critical in recent years, making it impossible to continue construction using traditional resources (cement, sand, and natural aggregates) in the same way as before. However, the use of earth is a cost-effective solution and it can enhance the sustainability of construction materials by employing soil as a building material. This study evaluated soil consistency that would be acceptable to make soil concrete and analysed the effect of chemical admixtures in achieving the maximum possible strength. Hence, the study suggested the possibility of using soil to form concrete as a replacement for cement concrete to the maximum extent with self-compacting properties. The soil was used to produce the concrete, stabilizing with cement and chemical admixtures were used to improve the strength and workability. According to the experimental investigation, it can be concluded that soil can be used as concrete with a characteristic strength of 15 MPa. The recommended native soil consistency for soil concrete should be developed by rearranging the native soil gradation to 5%–10% fines, 55%–71% sand, and 24%–40% gravel. The recommended cement amount as the stabilizer is 16% to 18% of the weight of the improved dry soil mixture. The strength and workability can be further improved by employing suitable chemical admixtures. Finally, this extensive study concluded that soil could be used to produce concrete for the construction industry through applications with minor improvements to the existing soil.

Elevated indoor carbon dioxide (CO₂) represents an underutilized biogenic carbon feedstock. Coupling indoor atmospheric remediation with biological sequestration requires overcoming mass-transfer limitations and culture collapse under high carbon loads. This study empirically evaluated a direct-injection, 2.0 L filamentous Leptolyngbya sp. photobioreactor for continuous indoor CO₂ valorization. A fortified nitrogen medium (4.5 g L⁻¹ NaNO₃) was utilized to sustain high-density proliferation. Initial optimization confirmed that narrow-band Red LEDs (10,000 lux) maximized the Apparent Quantum Efficiency (${\mathsf{\Phi }}_{{\mathrm{CO}}_2}$) at 1.49 × 10⁻³ mol/mol. During a 20-day continuous trial under 5000 ppm CO₂ sparging, the EPS-rich cyanobacterial matrix resisted acidification, achieving a stationary biomass density of 3.30 g L⁻¹. The system maintained a steady bio-mitigation velocity of ~2120 ppm day⁻¹. Intracellular chlorophyll a peaked at 26.0 mg L⁻¹ on Day 10, before severe optical self-shading induced a 47% photoprotective degradation, defining Day 10 as the optimal biorefinery harvesting threshold. At this peak, dynamic efficiency reached 2.07 × 10⁻³ mol/mol. Projecting these kinetics onto a 50 m³ occupied room confirms that capturing ambient CO₂ requires a working volume of 85–90 L and a spatial footprint of <0.25 m², validating Leptolyngbya sp. as a highly resilient catalyst for decentralized, commercial-scale indoor bioprocessing.