Repairing Concrete Cracks Using Bio-Influenced Self-Healing Techniques

Shaik Pedda Baji — 2026-07-09

This study aims to evaluate the crack-healing efficiency of bioconcrete by incorporating microorganisms and suitable nutrient precursors into the concrete matrix, to improve structural durability, reduce permeability, and extend the service life of concrete. When cracks form and water enters, dormant microorganisms activate, producing minerals that seal the fissures, enhancing concrete strength and longevity. An experimental program tested self-healing under various conditions, using methods like integrating bacteria into the mix, immobilizing them in lightweight aggregates, and combining with graphite nanoplatelets. Calcium lactate replaced about 5% of cement as a precursor. Specimens were cracked at intervals (3, 7, 14, and 28 days) to assess healing effectiveness. Results showed that bacteria in graphite nanoplatelets were more effective after 3 and 7 days, while lightweight aggregates excelled at 14 and 28 days, significantly improving compressive strength in the latter configuration. Furthermore, the bacterial self-healing mechanism effectively reduced crack width and water permeability, thereby enhancing the durability and service life of the concrete. The study concluded that the use of bacteria with suitable carrier materials offers a sustainable and eco-friendly alternative to conventional concrete repair techniques while minimizing long-term maintenance costs.

Investigating Carbon Emissions in the Healthcare Sector in Pakistan Based on Life Cycle Assessment

Muhammad Labib — 2026-07-01

Healthcare buildings are energy-intensive facilities, yet their lifecycle carbon emissions remain insufficiently studied in Pakistan. This study applies a Building Information Modelling (BIM)-integrated, cradle-to-grave Life Cycle Assessment to a single-storey healthcare facility in Murree, Pakistan, over a 50-year service life. Autodesk Revit 2024 was used to model the building and evaluate eight wall materials, five plaster materials, six insulation materials, and five roof systems. Thermal resistance, heat-transfer coefficients, peak heating load, and energy demand were calculated, while operational emissions were estimated using Pakistan’s grid emission factor of 0.52 kg CO₂/kWh. Embodied carbon was quantified from BIM-derived material quantities and published emission factors. Lightweight concrete blocks (W1) produced the largest reduction in peak heating load and associated CO₂ emissions (56.5%) relative to conventional clay brick walls. Lightweight plaster (P1), 2-inch polyurethane board insulation (INS1), and the high-performance roof system (R1) achieved reductions of 41.68%, 18.09%, and 19.51%, respectively. The optimized envelope reduced embodied carbon from 106.84 to 79.98 t CO₂ (25.1%) and lowered modelled total lifecycle CO₂ emissions by 41.92%. These findings demonstrate that practical envelope-material substitutions can substantially reduce carbon emissions from Pakistani healthcare buildings and provide quantitative guidance for hospital design, retrofit planning, and low-carbon building policy.

Journal of Recent Activities in Infrastructure Science

Repairing Concrete Cracks Using Bio-Influenced Self-Healing Techniques

Investigating Carbon Emissions in the Healthcare Sector in Pakistan Based on Life Cycle Assessment