Nepal's health sector vulnerabilities were exposed during the 2015 Gorkha earthquake, which prompted immediate reconstruction efforts. This disaster underscored the need for enhanced healthcare infrastructure throughout the country but encountered numerous challenges. This study aims to investigate the challenges faced during the post-earthquake reconstruction of health sector building projects in rural Nepal. Five major challenges were identified through a literature review, namely "resource challenges", "legal challenges", "physical and territorial challenges", "management and coordination challenges" and "social and cultural challenges". Perceptions on identified challenges were collected from 137 clients, consultants, and contractors working on 106 ongoing building construction projects in 9 districts across 3 provinces funded by the Government of India. Structural equation modeling (SEM) using the partial least squares (PLS) method was conducted with SmartPLS version 3 to identify the major challenges. All five challenges were found to be significant, with "resource challenges" being the most significant (β= 0.613), followed by "legal challenges", "physical and territorial challenges", "management and coordination challenges" and "social and cultural challenges". Based on these findings, it is suggested that Nepal should adopt a comprehensive strategy that includes proper resource management, improved legal frameworks, effective coordination between stakeholders, and an understanding of social and cultural dynamics to overcome these challenges. Therefore, all project stakeholders must collaborate to address these challenges, which will ensure a resilient and sustainable healthcare infrastructure in earthquake-prone regions like Nepal.

Corrosion of steel reinforcement is a major factor affecting the durability and strength of reinforced concrete structures. This study investigated the influence of plant-derived corrosion inhibitors, applied as coatings, on the bond strength between reinforcing steel and concrete. Thirty-six 150 mm concrete cubes with 12 mm diameter embedded steel bars were prepared and divided into uncoated, corrosion inhibitor coated, and control groups. The samples were immersed in 5% sodium chloride solution over 360 days to accelerate corrosion. Pull-out testing measured the bond strength and failure load. The corroded samples showed 31-26% lower bond strength and 82-87% higher maximum slip than controls, indicating corrosion damage at the steel-concrete interface. However, inhibitor-coated samples displayed 24-36% higher bond strength and 42-43% lower maximum slip versus corroded samples. Although the coatings did not fully restore original bond strength, this demonstrates their effectiveness at protecting bond properties. Microscopic analysis revealed non-uniform, localized corrosion preferentially initiated at steel defects. Statistical correlations confirmed the direct relationship between steel weight loss and reductions in post-corrosion rebar weight due to material loss. While nominal rebar diameters showed minimal differences between sample types, localized diameter reductions and cross-sectional area increases in corroded samples highlighted discrete corrosion effects. These were mitigated in coated samples. Together with direct weight loss measurements, this proves corrosion occurred in unprotected samples. Overall, the significant recovery of bond strength, slip resistance, diameter, area, and weight in coated samples validates the success of the natural corrosion inhibitors in reducing steel deterioration and interface degradation. The results provide new insights on optimizing inhibitor coatings to maximize corrosion protection for reinforced concrete structures.

This study investigated the effect of corrosion on the flexural behavior and midspan deflection of reinforced concrete beam members. Control, corroded, and resin-coated concrete beam specimens were tested to determine their failure load, midspan deflection, rebar diameter measurements, and mechanical properties. The results showed that corrosion significantly reduced the flexural strength and increased the midspan deflection of beams due to weakening of the reinforcing steel. The average failure load of corroded beams decreased by 25.73% compared to the control beams. Similarly, the average midspan deflection of corroded beams increased by 103.8% over the control beams. Measurements of rebar diameters before and after corrosion revealed reductions of up to 0.87% in corroded samples, substantiating corrosion-induced thinning. Additionally, mechanical properties testing showed decreases in ultimate tensile strength, yield strength, and strain ratio while increasing ductility for corroded rebars. Resin coating prevented much of the strength loss and provided protective benefits near that of the control specimens. The relationship between failure load, midspan deflection, diameter measurements, mechanical properties and corrosion damage was investigated through analytical comparisons. Corroded samples consistently demonstrated lower failure loads, higher deflections, reduced diameters and strengths versus controls. Conversely, coated samples performed similarly to controls, validating the coating's effectiveness. This research quantitatively confirms literature reports that corrosion degrades reinforced concrete through weakening of rebar-concrete bond and steel deterioration over time if left unprotected. The findings emphasize the importance of mitigating corrosion to ensure structural integrity, safety and durability of reinforced concrete infrastructure.