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Concrete is subjected to elevated temperature for short duration, long duration and cyclic heating on many occasions. The dramatic fire accidents/incidents have renewed the interest in the area of research on concrete subjected to elevated temperature. From the literature review it is found that the experimental data which simulate the conditions of structural elements in stressed conditions when exposed to fire are scarce. The work presents a study on the residual characteristics of R.C. beams subjected to elevated temperature under unstressed and stressed conditions. The R.C beams were of size 120mm×120mm×1500mm and designed with single and double reinforcement and referenced as Type I and Type II respectively. M20 grade of concrete was used in casting the beams. The temperatures were kept as 100°C, 200°C, 300°C, 400°C and 500°C and the duration of exposure was 4 hours. The specimens were cooled in air and the residual properties were tested by conducting two point bending test on R.C. beams and their behavioral parameters were studied in comparison with beams tested under normal (room) temperature conditions. The extent of damage suffered measured by the damage factor was about 32 % for Type I beams and about 48% for the Type II beams tested under unstressed test condition when exposed to 500°C; whereas it is to an extent of 33% for Type I beams and 49% for Type II beams in stressed test condition for the same exposed temperature. The degradation in initial stiffness was nearly 57% and 49% for Type I and Type II beams in unstressed test and 54% and 73% respectively for stressed test when exposed to 500°C. The degradation in stiffness at 50% of ultimate load was nearly 36% and 35% for Type I and Type II beams in unstressed test and 49% and 76.6% respectively for stressed test when exposed to 500°C. The ultimate load of R.C. beams tested in stressed condition were marginally 5% lower than the beams under unstressed test condition.

Using coconut shell aggregates (CSA) in concrete benefits agricultural waste management and reduces the demand for mineral resources. Several studies have found that concrete containing CSA can achieve strengths that are comparable to regular concrete. The purpose of the present work is to evaluate the concrete’s durability-related properties to supplement these earlier findings.

Cylindrical specimens were prepared with a constant water–cement ratio of 0.50 and CSA content ranging from 0% to 50% (at 10% increment) by volume of the total coarse aggregates. The specimens were cured for 28 days and then tested for density, surface hardness, electrical resistivity and water sorptivity. The surface hardness was measured to describe the concrete resistance to surface wearing, while the resistivity and sorptivity were evaluated to describe the material’s resistance to fluid penetration.

The results showed that the surface hardness of concrete remained on average at 325 Leeb and did not change significantly with CSA addition. The distribution of surface hardness was also similar across all CSA groups, with the interquartile range averaging 59 Leeb. These results suggest that the cement paste and gravel stiffness had a more pronounced influence on the surface hardness than CSA. On the other hand, concrete became lighter by about 9%, had lower resistivity by 80% and had significantly higher initial sorptivity by up to 110%, when 50% of its natural gravel was replaced with CSA. Future work may be done to improve the durability of CSA when used as coarse aggregate.

The present study is the first to show the lack of correlation between CSA content and surface hardness. It would mean that the surface hardness test may not completely capture the porous nature of CSA-added concrete. The paper concludes that without additional treatment prior to mixing, CSA may be limited only to applications where concrete is not in constant contact with water or deleterious substances.

The Reinforced Concrete(RC) elements are known to perform well during exposure to elevated temperatures. Hence, RC elements are widely used to resist the extreme heat developing from accidental fires and other industrial processes. In both of the scenarios, the RC element is exposed to elevated temperatures. However, the primary differences between the fire and processed temperatures are the rate of temperature increase, mode of exposure and exposure durations. In order to determine the effect of two heating modalities, RC beams were exposed to processed temperatures with slow heating rates and fire with fast heating rates.

In the present study, RC beam specimens were exposed to 200 °C, to 800 °C temperature at 200 °C intervals for 2 h' duration by adopting two heating modes; Fire and processed temperatures. An electrical furnace with low-temperature increment and a fire furnace with standard time-temperature increment is adapted to expose the RC elements to elevated temperatures.

It is observed from test results that, the reduction in load-carrying capacity, first crack load, and thermal crack widths of RC beams exposed to 200 °C, and 600 °C temperature at fire is significantly high from the RC beams exposed to the processed temperature having the same maximum temperature. As the exposure temperature increases to 800 °C, the performance of RC beams at all heating modes becomes approximately equal.

In this work, residual performance, and failure modes of RC beams exposed to elevated temperatures were achieved through two different heating modes are presented.

In recent years, the use of earth as a material applied to construction has been adapted as an attractive alternative to modern concepts. The earth construction technique takes advantage of regional natural resources, among which are earth bricks. The purpose of this paper is to analyze the effect of the addition of coconut fibers and aloe vera on the mechanical properties of compressed earth blocks (CEB).

CEBs were manufactured from silty and clay soil (Altamira, Tamaulipas, Mexico) with biodegradable stabilizers of aloe vera and short coconut mesocarp fibers, which were compared with the conventional mixture with lime as stabilizer. The samples were subjected to compression tests (Mexican Standard NMX-C-404-ONNCC3-205), flexion (NMX-C083-ONNCCE.), abrasion (NTC-5324 3.4.3), water absorption (NMX-C-37-ONNCE-205), surface morphology and thermal properties (ASTM D5334-14).

It was found that the addition of coconut fibers has a 12% difference in flexural strength. The addition of 0.5% of coconut fibers decreases swelling by 2% with water and reduces the thermal conductivity of the material by 12%. Likewise, this mixture increases the abrasion resistance of CEB by 30%. When there is a pressure greater than 1,700 psi in the CEB, the addition of coconut fibers does increase the compressive strength of the material, showing a 34% improvement over the CEB without adding coconut fibers.

The authors show a new sustainable CEB production with aloe vera and coconut fiber that is possible for self-production with better mechanical properties than others, commonly produced in Mexico.

The purpose of the paper is to explore the impact of board size on the accounting returns and asset quality of Indian banks.

This paper uses ordinary least squares regression, robust regression and panel data methods for estimation, based on data collected for a sample of 29 Indian banks that are listed on the National Stock Exchange (NSE) and form part of the NSE-500 index over a period of eight financial years 2009-2016. The data pertaining to the board size of the sample banks is collected from the annual reports of banks, whereas the data relating to return on assets (ROA) and ratio of the gross non-performing assets to total assets and control variables (bank age and bank size) is extracted from ACE Equity database.

This paper concludes that the size of the governing board has a positive impact on the accounting returns (measured through ROA) of the Indian banks. Further, board size is observed to be insignificant in determining the asset quality of Indian banks.

This paper contributes to the literature and practitioners in a number of ways. First, to the best of the authors’ knowledge, this is the first study on the impact of board size on the accounting returns and asset quality of Indian banks. The findings of the study contribute new theoretical insights to the body of knowledge on the influence of the size of the board, which may be useful for future researchers. Second, banks may enhance their financial performance by taking cognizance of the findings of this study. Finally, equity investors may make use of the findings of this article in deciding on whether to invest in a bank’s stock/lend to the bank based on board size of the bank.

This review paper seeks to enhance knowledge of how pre-loading affects reinforced concrete (RC) beams under fire. It investigates key factors like deflection and load capacity to understand pre-loading's role in replicating RC beams' actual responses to fire, aiming to improve fire testing protocols and structural fire engineering design.

This review systematically aggregates data from existing literature on the fire response of RC beams, comparing scenarios with (WP) and without pre-loading (WOP). Through statistical tools like the two-tailed t-test and Mann–Whitney U-test, it assesses deflection extremes. The study further examines structural responses, including flexural and shear behavior, ultimate load capacity, post-yield behavior, stiffness degradation and failure modes. The approach concludes with a statistical forecast of ideal pre-load levels to elevate experimental precision and enhance fire safety standards.

The review concludes that pre-loading profoundly affects the fire response of RC beams, suggesting a 35%–65% structural capacity range for realistic simulations. The review also recommended the initial crack load as an alternative metric for determining the pre-loading impact. Crucially, it highlights that pre-loading not only influences the fire response but also significantly alters the overall structural behavior of the RC beams.

The review advances structural fire engineering with an in-depth analysis of pre-loading's impact on RC beams during fire exposure, establishing a validated pre-load range through thorough statistical analysis and examination of previous research. It refines experimental methodologies and structural design accuracy, ultimately bolstering fire safety protocols.

This paper aims to identify the different system approach using building information modelling (BIM) technology that is equipped with automated evaluation processes. BIM research has mainly focused on theoretical models of acceptance in the green building (GB) maintenance industry. However, BIM has the potential to the competency’s performance and design knowledge of building control instrument. Realising this potential requires a study of BIM at the maintenance planning level, which is considered to be BIM-based model checking (BMC). BMC and its effect in the maintenance planning have not been sufficiently investigated.

The aim of this paper is to present a critical review of literature on the theoretical background of BMC practices and the main features of information and communication technology tools and techniques in the GB maintenance projects.

A theoretical framework of BMC is developed and presented. The proposed model incorporates requirement for maintaining a competency’s performance on maintenance planning schemes of GB projects and the importance of early integration of BMC in the design phase to identify alternative methods to cogenerate, monitor and optimise BMC.

It is found that variables facilitating BMC are integrated at different GB maintenance environments levels and are shaped by the context. Directions for future research are presented.

In recent years, the partially averaged Navier–Stokes (PANS) methodology has earned acceptability as a viable scale-resolving bridging method of turbulence. To further enhance its capabilities, especially for simulating separated flows past bluff bodies, this paper aims to combine PANS with a non-linear eddy viscosity model (NLEVM).

The authors first extract a PANS closure model using the Shih’s quadratic eddy viscosity closure model [originally proposed for Reynolds-averaged Navier–Stokes (RANS) paradigm (Shih et al., 1993)]. Subsequently, they perform an extensive evaluation of the combination (PANS + NLEVM).

The NLEVM + PANS combination shows promising result in terms of reduction of the anisotropy tensor when the filter parameter (f_k) is reduced. Further, the influence of PANS filter parameter f on the magnitude and orientation of the non-linear part of the stress tensor is closely scrutinized. Evaluation of the NLEVM + PANS combination is subsequently performed for flow past a square cylinder at Reynolds number of 22,000. The results show that for the same level of reduction in f_k, the PANS + NLEVM methodology releases significantly more scales of motion and unsteadiness as compared to the traditional linear eddy viscosity model (LEVM) of Boussinesq (PANS + LEVM). The authors further demonstrate that with this enhanced ability the NLEVM + PANS combination shows much-improved predictions of almost all the mean quantities compared to those observed in simulations using LEVM + PANS.

Based on these results, the authors propose the NLEVM + PANS combination as a more potent methodology for reliable prediction of highly separated flow fields.

Combination of a quadratic eddy viscosity closure model with PANS framework for simulating flow past bluff bodies.

This paper aims to focus on studying the batch desorption of adsorbed crystal violet (CV) from date stones (Phoenix dactylifera), untreated (UDS) and treated using NaOH (TDS).

The process variables such as different desorbing agents, volume and concentration of the desorbing agent, contact time, dye concentration before adsorption and temperature affecting CV desorption from CV-loaded untreated date stones (CV@UDS) and treated adsorbent (CV@TDS) were optimized. The UDS and TDS were regenerated using 0.6 m HCl as eluent.

The HCl solution was an excellent eluent for the CV desorption from CV@UDS (96.45%) and CV@TDS (98.11%). The second-order model and the Langmuir model well exemplified experimental data with maximum desorption capacities were 63.29 mg g⁻¹ for the CV@UDS and 243.90 mg g⁻¹ for the CV@TDS. The calculated thermodynamic showed that the CV desorption was spontaneous, endothermic and physical. Good regeneration and reusability of UDS and TDS for the CV removal for four consecutive adsorption–desorption cycles.

This study provided a good example of reusing UDS and TDS with NaOH for fast removal of a toxic organic pollutant, CV from the wastewaters.

The use of UDS and TDS with NaOH for the first time for desorption study and their reusability to removing CV from their aqueous solutions.

There are no adequate records on the nutrition of the people living with HIV/AIDS in Nigeria. This paper aims to rectify this.

Purposive sampling technique was used to select 200 PLWHA respondents at the Federal Medical Center Idiaba, Abeokuta. A pre‐tested questionnaire was used to collect information on the subjects’ socio‐demographic characteristics and health status of respondents. A three day 24‐hour recall was used to assess the food intake of the subjects. Adequacy of nutrient intake was assessed as a percentage of the recommended dietary allowance. Packed cell volume (PCV) estimation was investigated using a sub‐sample of 100 respondents.

The values obtained were compared with WHO/UNICEF/UNU reference values. The mean PCV for the 33 men was 31.9±6.62 while the mean value for the remaining 67 females was 29.4±4.87, which was below the reference values. A positive correlation was obtained between the PCV and energy intake (r=0.528, 33; p<0.01) as well as serum iron (r=0.474; p<0.01).

This study suggests that a healthy diet that is adequate in terms of energy, protein, fat, and other essential nutrients should be promoted in Nigeria as a key component of positive living for people with HIV.

This paper may be the first to evaluate the nutrient intake and health status of HIV/AIDS patients in Abeokuta, Nigeria