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The consumption of supplementary cementitious materials (SCMs) has increased enormously in the construction industry. These SCMs are often waste materials or industrial by-products. This study aims to investigate the bond strength using reinforcing bars in Normal Strength Concrete (M20 grade) and High Strength Concrete (M40 grade), developed using SCMs and data was compared with concrete prepared with ordinary portland cement (OPC). The findings of the study will help in reducing the dependency on OPC and promote the utilization of waste materials in Construction.

In the present study, the bond behavior between the steel bars and the concrete was investigated in controlled, binary and quaternary concretes of M20 and M40 grades. Following the conventional procedures, samples were prepared and mechanical tests conducted (as per IS:2770–1 code for M20 and M40 grade concrete structures), which showed an improvement in the bond strength depending on the extent of overall calcium and silica content in these composite mixtures, and thus reflected the importance of vigilant utilization of used industrial waste in the OPC as a replacement without exceeding silica content beyond certain percentages for enhanced structural properties.

Experimental evaluation of bond behavior results showed a brittle nature for the controlled (OPC) concrete mixtures. While binary and quaternary concrete was able to resist the load-carrying capacity under large deformations and prevented the split cracking and disintegration of the concretes. Among different variations in the chemistry, for both M20 and M40 grades, the maximum bond strengths were observed for 10% Metakaolin + 10% Silica Fume + 30% Fly Ash + 50% OPC composition and this could be attributed to the fineness of the additives, better packing and enhanced calcium silicate hydrate (C-S-H).

Quaternary concrete may be a future option in place of OPC concrete. Very limited data is available related to the bond strength of quaternary concrete. Experimental analysis on quaternary concrete shows that its use in construction can reduce both construction cost and a burden on natural raw materials used to make OPC.

This paper focusses on how the educated and less-educated middle class react differently to income increases, against an intertwined literature backdrop of Engel's law, quality of life, aspirational and conspicuous consumption. The paper seeks to answer two main questions: Is there evidence of the middle class, particularly the educated, trying to emulate the upper class by shifting towards aspirational consumption? Is there any distinct expenditure behaviour amongst the middle class?

Combining the Malaysian 2016 Household Expenditure Survey (HES) and the 2016 Consumer Price Indices datasets, quantile estimations are applied on the merged dataset of 14,326 households.

There is evidence of the educated middle class emulating the upper class in terms of food share, home furnishing and starchy produce expenditure behaviour. The less-educated middle class exhibits a predilection for home furnishing expenditures when income increases, whilst the educated shows signs of dissociating themselves from such material acquisitions. The paper concludes that the middle class is collectively an aspirational class, but with diverging paths towards upward social mobility between the educated and less-educated households.

Aspirational consumption of the middle class has not been given detailed empirical treatment at the household micro-level in the literature, especially for upper-middle income countries like Malaysia. The paper starts off by detecting an anomaly in the Engel's food share coefficients, where the middle class sees unexpected larger declines in food share than those of the upper class. This is the paper's departure point from the literature.

This study aims to investigate the compressive strength of concretes incorporating Linz-Donawitz slag (LD slag) as partial replacement for natural fine and coarse aggregates and compare them with traditional concrete.

The natural fine and coarse aggregates were replaced by weight simultaneously up to 100% with LD slag aggregates at an incremental increase of 20%. Concrete of grades M20, M25, M30, M35 and M40 were cast, cured and tested with standard cube specimens to study the density and compressive strength of reference and LD slag aggregate concretes (LDSACs). The concrete specimens were exposed to elevated temperatures, i.e. 100 to 900 °C at an equal interval of 100 °C and tested to study the variation in density and residual compressive strength.

The results from the experiments reveal that the LDSAC yields a higher density than that of the reference concrete and also undergo less density variation when exposed to elevated temperatures. In addition, the residual compressive strength of LDSAC specimens was significantly higher than that of the reference concrete.

LD slag is believed to be stronger and more durable than locally available limestone aggregates or blast furnace slag. Moreover, it is necessary to study its strength and other properties to determine whether it can be successfully used as an aggregate in concrete universally.

Use of LD slag as aggregates in concrete will convert LD slag into a value added product and as an alternative to the existing natural aggregates which will help in maintaining ecological balance and save valuable lands.

The economically weaker section of the society may now use LDSAC as waste utilization will bring down the overall cost and hence it will benefit people on large scale.

Use of LD slag as aggregate in concrete can help find an alternative to the existing natural aggregates which will save the ecosystem and at the same time help in reducing the industrial waste on a large scale.

Building elements that are damaged by fire are often strengthened by fiber wrapping techniques. Self-compacting concrete (SCC) is an advanced building material that is widely used in construction due to its ability to flow and pass through congested reinforcement and fill the required areas easily without compaction. The aim of the research work is to examine the flexural behavior of SCC subjected to elevated temperature. This research work examines the effect of natural air cooling (AC) and water cooling (WC) on flexural behavior of M20, M30, M40 and M50 grade fire-affected retro-fitted SCC. The results of the investigation will enable the designers to choose the appropriate repair technique for improving the service life of structures.

In this study, an attempt has been made to evaluate the flexural behavior of fire exposed reinforced SCC beams retrofitted with laminates of carbon fiber reinforced polymer (CFRP), basalt fiber reinforced polymer (BFRP) and glass fiber reinforced polymer (GFRP). Beam specimens were cast with M20, M30, M40 and M50 grades of SCC and heated to 925ºC using an electrical furnace for 60 min duration following ISO 834 standard fire curve. The heated SCC beams were cooled by either natural air or water spraying.

The reduction in the ultimate load carrying capacity of heated beams was about 42% and 55% for M50 grade specimens that were cooled by air and water, respectively, in comparison with the reference specimens. The increase in the ultimate load was 54%, 38% and 27% for the specimens retrofitted with CFRP, BFRP and GFRP, respectively, compared with the fire-affected specimens cooled by natural air. Water-cooled specimens had shown higher level of damage than the air-cooled specimens. The specimens wrapped with carbon fiber could able to improve the flexural strength than basalt and glass fiber wrapping.

SCC, being a high performance concrete, is essential to evaluate the performance under fire conditions. This research work provides the flexural behavior and physical characteristics of SCC subjected to elevated temperature as per ISO rate of heating. In addition attempt has been made to enhance the flexural strength of fire-exposed SCC with wrapping using different fibers. The experimental data will enable the engineers to choose the appropriate material for retrofitting.

The purpose of this study is to investigate the effect of standard fire on the strength and microstructure properties of concrete with different strength grades.

Different strength grades of concrete used for the investigation are M20, M30, M40 and M50. An electrical bogie hearth furnace was developed to simulate the International Standards Organization 834 standard fire curve.Concrete samples were subjected to high temperatures of 925, 1,029, 1,090 and 1,133°C for the duration of 1, 2, 3 and 4 h, respectively, as per standard fire curve. Compressive strength, tensile strength, thermal crack pattern and spalling of heated concrete specimens were evaluated by experimental investigation. Scanning electron microscopy and thermo-gravimetric analysis were performed to investigate the microstructure properties of heated concrete specimens.

Test results indicated reduction in the strength and changes in the microstructure properties of concrete exposed to elevated temperature. The degree of weight and the strength loss were found to be higher for concrete with higher grades. An empirical relation is proposed to determine the residual strength of concrete with different strength grade using regression analysis.

Results of this research will be useful for the design engineers to understand the behavior of concrete exposed to elevated temperature as per standard fire.

When concrete is exposed to elevated temperature, its internal microstructure changes, thereby strength and durability of concrete deteriorates. The performance of concrete with different strength grade exposed to standard fire is well understood. This research’s findings will be useful for the designers to understand more about fire resistance of concrete. A simple relationship is proposed to determine the residual strength of concrete exposed to various durations of heating.

The purpose of this paper is to empirically explore the financial well-being (FWB) of Malaysian households and to construct a subjective FWB index with present and future time perspectives.

Data were collected from 1,867 respondents across five major regions in Malaysia. Adapting the InCharge Financial Distress/Financial Well-being (IFDFW) Scale by Prawitz et al. (2006) and the method of computing an index by Devlin (2009), this study develops an FWB index using subjective measures that include future time perspectives (retirement). The index was employed to measure the FWB across low-, middle- and high-income groups and socio-demographic characteristics.

This study finds evidence that Malaysians' FWB is at an average level (46.8). Middle-income households' FWB (46.1) flanks between the financial well-being index (FWBI) levels of the low-income (37.4) and high-income households (58.7). Across age groups, education levels and employment sectors, the FWB of Malaysians significantly varies, although not across different ethnics, religions, zones and residential areas. Overall, the results suggest that the detrimental effects of FWB are perceived by all Malaysian households nationwide regardless of their religion, ethnicity and residential areas.

The results of this study complement the other well-being indices used by policymakers and may serve as a useful input for government and policymakers for them to formulate appropriate strategies to promote higher FWB of Malaysian households based on their socio-demographic characteristics.

This study used primary data and developed a subjective FWB index that leverages on people's perceptions of their own financial well-being while including present and future time perspectives. The main contribution of this paper is to construct an index that is easily interpretable and that complements the existing FWB indices, and to identify the segments of society that have low vis-à-vis high FWB.

Automobiles have always been a major cause of air pollution. The vehicular emission contains several harmful pollutants that affect the surroundings and living beings. Mild CO exposure leads to headaches or unconsciousness. CO is also responsible for the global warming as well. CO is mainly generated in the IC engine due to incomplete combustion of the fuel. The purpose of this paper is to implement a CO absorption mechanism inside the exhaust pipe of vehicle.

In this research work the single cylinder four stroke spark-ignition engine is intended to run on petroleum and petroleum blended fuels. A new post-combustion emission control device called cobalt scrubber is employed to reduce the emission of CO during idling which absorb and later release it under transient conditions.

The emission of CO when the engine runs at petroleum is reduced from 6.24 to 3.02 per cent. Methanol 40 per cent+petrol 60 per cent gives a better emission result of 0.98 per cent of CO emission. So, the authors can implement the cobalt scrubber in automobiles to avoid CO emission during idling.

The scrubber clearly overcomes the drawbacks of the existing control techniques. The cobalt scrubber is a cheap, non-radioactive. It can be employed in any kind of vehicle irrespective of its engine.

The use of the scrubber design presented in this article, effectively reduces the emission of CO.

Aim of this research work is to examine the stress–strain behavior and modulus of elasticity of fiber-reinforced concrete (FRC) exposed to elevated temperature. The purpose of this paper is to study the effect of standard fire exposure on the mechanical and microstructure characteristics of concrete specimens with different strength grade.

An electrical bogie hearth furnace was developed to simulate the ISO 834 standard fire curve. Specimens were exposed to high temperatures of 821°C, 925°C and 986°C for the duration of 30, 60 and 90 min, respectively, as per standard fire curve. Peak stress, peak strain, modulus of elasticity and damage level of heated concrete specimens were evaluated by experimental investigation. SEM-based microstructure investigation has been carried out to analyze the microstructure characteristics of heated concrete specimens.

The results revealed that carbon fiber reinforced concrete was found to be better than the FRC made with other fibers on improving the modulus of elasticity of concrete. An empirical relationship has been established to predict the modulus of elasticity of temperature exposed specimens with different type of fiber and grade of concrete. In comparison with low melting point fibers, high melting point fibers exhibited higher modulus of elasticity under all tested conditions. Surface damage and porosity level of concrete with carbon and basalt fibers were found to be lower than other FRC.

Empirical relationship was developed to determine the modulus of elasticity of concrete exposed to elevate temperature, and this will be useful for concrete design applications. This research work may be useful for finding the residual compressive strength of concrete exposed to elevate temperature. So that it will be helpful to identify the suitable repair/retrofitting technique for reinforced concrete elements.

Health is considered as a nucleus to the life of a nation. Absence of it can create disharmony to an individual and society at large. Recent phenomena of COVID-19 pandemic outbreak which has penetrated into the lives of masses has caused major chaos and adverse effect to the health and wellbeing of people globally. No doubt that absence of health may create a magnetic wave to attract abundance of funds for the purpose of mitigating or dealing not only with such pandemic, but for other types of diseases that emerged as well. This is partially because wealth and health have an interrelationship that is hard to separate. This chapter primarily aims to discuss on how Islamic ethical wealth, i.e., waqf has the potential to influence the good health and wellbeing of people. Specifically, this chapter aims to provide a new model of waqf instrument to realize the concept of Islamic ethical wealth. The concept of fairness and justice in Islamic ethical wealth is used in this chapter. Such concept is crucial in distributing wealth and resources for the betterment of health and wellbeing of the masses. This chapter provides solution and suggestion to uphold the primary ethics in wealth through waqf system.

The purpose of this study is to investigate the behaviour of M40 grade of self-compacting concrete (SCC) with high volume of ground granulated blast furnace slag (GGBS) (50%) and recycled concrete aggregate (RCA) content up to 100% to assess the mechanical properties of SCC. As per guidelines of IS: 383 – 2016, the RCA can be replaced up to 20% of natural coarse aggregate up to M25 grade of concrete. This study assesses the mechanical properties of SCC beyond 20% of RCA content. Based on the experimental investigations, the compressive strength of mixes decreases as the content of RCA increases. It is found that concrete mixes with 20% RCA and shows the maximum compressive strength at 56 days.

The fresh properties as per EFNARC and IS: 10262–2019 guidelines, ultrasonic pulse velocity testing, mechanical properties and microstructure analysis have been conducted to evaluate the performance of SCC with RCA for practical applications.

From the experimental investigations, it is found that up to 50% of recycled coarse aggregate can be used for structural applications.

The environmental pollution and dumping of waste on green land can be reduced by effective utilization of recycled coarse aggregate and GGBS in the production of SCC.