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Fatigue and creep are the key factors for the failure of polymethyl methacrylate (PMMA) in the engineering structure, so a great of quantity attention is focused on the life prediction under the creep and fatigue conditions. This paper aims to mainly summarize the traditional life assessment method (S–N curve), life assessment method based on crazing density and life assessment method based on transmittance. S–N curve and classical creep curve are introduced on the traditional life assessment method; the variation of the craze density with the logarithm of cyclic numbers is given in different fatigue load. A linear relationship is obtained, and a higher stress leads to a higher slope, suggesting a faster growth of craze. Furthermore, a craze density model is purposed to describe this relationship; the variation of craze density with the time at different creep load is given. The craze density has two obvious stages. At the first stage, craze density ranged from approximately 0.02 to 0.17, and a linear relationship is obtained. In the following stage, a nonlinear relationship appears till specimen rupture, a new creep life model is proposed to depict two stages. The relationship between transmission and time under creep load is shown. With increasing of time, the transmittance shows a nonlinear decrease. Through polynomial nonlinear fitting, a relationship between the transmittance and residual life can be obtained. To provide reference for the life assessment of transparent materials, the paper compares three life assessment methods of PMMA.

This paper uses the traditional life assessment method (S–N curve), life assessment method based on crazing density, life assessment method based on transmittance.

The variation of the craze density with the logarithm of cyclic numbers is given in different fatigue loads. A linear relationship is obtained, and a higher stress leads to a higher slope, suggesting a faster growth of craze. Furthermore, a craze density model is proposed to describe this relationship, and the variation of craze density with the time at different creep loads is given. The craze density has two obvious stages. The relationship between transmission and time under creep load is shown. With increasing of time, the transmittance shows a nonlinear decrease. Through polynomial nonlinear fitting, a relationship between the transmittance and residual life can be obtained.

Fatigue and creep are the key factors for the failure of PMMA in the engineering structure, so a great of quantity attention is focused on the life prediction under the conditions of creep and fatigue. This paper mainly summarizes traditional life assessment method (S–N curve), life assessment method based on crazing density and life assessment method based on transmittance.

This research was motivated and initiated by a request from industry to present a life skills learning programme to supplement young workers’ training. Subsequently, the dilemma faced by facilitators and trainers to assess the learners’ attainment of the learning outcomes of a life skills learning programme provided the impetus to develop an alternative assessment method – the collage and the stimulus instruments. A model developed by the researchers guided the development of the alternative assessment method and the stimulus instruments. Taking into account the demands, requirements and characteristics of life skills, a collage consisting of ten pictures and ten verbal concepts was developed to assess the learners’ attainment of the learning outcomes of a particular life skills learning programme. The life skills learning programme was presented to 18 artisans employed in industry. The selected material in the collage depicts more than one life skill and reflects the learning outcomes of the programme. The article is published in two parts. Part 1 is outlined above. The second part of the article will report on the outcomes of the application of the assessment instrument with the subject group of young workers.

The purpose of this paper is to present the durability analysis in predicting the reliability life cycle for an automobile crankshaft under random stress load using the stochastic process. Due to the limitations associated with the actual loading history obtained from the experimental analysis or due to the sensitivity of the strain gauge, the fatigue reliability life cycle assessment has lower accuracy and efficiency for fatigue life prediction.

The proposed Markov process embeds the actual maximum and minimum stresses by a continuous updating process for stress load history data. This is to reduce the large credible intervals and missing loading points used for fatigue life prediction. With the reduction and missing loading intervals, the accuracy of fatigue life prediction for the crankshaft was validated using the statistical correlation properties.

It was observed that fatigue reliability corresponded well by reporting the accuracy of 95–98 per cent with a mean squared error of 1.5–3 per cent for durability and mean cycle to failure. Hence, the proposed fatigue reliability assessment provides an accurate, efficient, fast and cost-effective durability analysis in contrast to costly and lengthy experimental techniques.

An important implication of this study is durability-based life cycle assessment by developing the reliability and hazard rate index under random stress loading using the stochastic technique in modeling for improving the sensitivity of the strain gauge.

The durability analysis is one of the fundamental attributes for the safe operation of any component, especially in the automotive industry. Focusing on safety, structural health monitoring aims at the quantification of the probability of failure under mixed mode loading. In practice, diverse types of protective barriers are placed as safeguards from the hazard posed by the system operation.

Durability analysis has the ability to deal with the longevity and dependability of parts, products and systems in any industry. More poignantly, it is about controlling risk whereby engineering incorporates a wide variety of analytical techniques designed to help engineers understand the failure modes and patterns of these parts, products and systems. This would enable the automotive industry to improve design and increase the life cycle with the durability assessment field focussing on product reliability and sustainability assurance.

The accuracy of the simulated fatigue life was statistically correlated with a 95 per cent boundary condition towards the actual fatigue through the validation process using finite element analysis. Furthermore, the embedded Markov process has high accuracy in generating synthetic load history for the fatigue life cycle assessment. More importantly, the fatigue reliability life cycle assessment can be performed with high accuracy and efficiency in assessing the integrity of the component regarding structural integrity.

Life Cycle Assessment (LCA) aims to analyze possible impact upon manufacturing process and availability of products, and also study the environmental considerations and potential influence during entire life cycle ranging from procurement, production and utilization to treatment (namely, from cradle to tomb). Based on high‐density polyethylene (HDPE) pipe manufacturing of company A, this case study would involve evaluation of environmental influence during the production process. When the manufacturing process has been improved during “production process” and “forming cooling” stage, it is found that capital input on “electric power” and “water supply” could be reduced, thus helping to sharpen the competitive power of company A, and also ensure sustainable economic and industrial development in accordance with national policies on environmental protection.

The purpose of this study is to evaluate the sustainability performance of modular construction from a life cycle perspective. So far, the sustainability performance of modular buildings has been explored from a life cycle viewpoint. There is no comprehensive study showing which material is the best choice for modular construction considering all three sustainable pillars. Therefore, a life cycle sustainability performance framework, including the three-pillar evaluation framework, was developed for different modular buildings. The materials are concrete, steel and timber constructed as a modular construction method.

Transitioning the built environment to a circular economy is vital to achieving sustainability goals. Modular construction is perceived as the future of the construction industry, and in combination with objective sustainability, it is still in the evaluation phase. A life cycle sustainability assessment, which includes life cycle assessment, life cycle cost and social life cycle assessment, has been selected to evaluate alternative materials for constructing a case study building using modular strategies. Subsequently, the multi-criteria decision-making (MCDM) method was used to compute the outranking scores for each modular component.

The calculated embodied impacts and global warming potential (GWP) showed that material production is the most critical phase (65%–88% of embodied energy and 64%–86% of GWP). The result of embodied energy and GWP shows timber as an ideal choice. Timber modular has a 21% and 11% lower GWP than concrete and steel, respectively. The timber structure also has 19% and 13% lower embodied energy than concrete and steel. However, the result of the economic analysis revealed that concrete is the most economical choice. The cost calculations indicate that concrete exhibits a lower total cost by 4% compared to timber and 11% higher than steel structures. However, the social assessment suggests that steel emerges as the optimal material when contrasted with timber and concrete. Consequently, determining the best single material for constructing modular buildings becomes challenging. To address this, the MCDM technique is used to identify the optimal choice. Through MCDM analysis, steel demonstrates the best overall performance.

This research is valuable for construction professionals as it gives a deliberate framework for modular buildings’ life cycle sustainability performance and assists with sustainable construction materials.

Environmental impact and changes are becoming essential in textile and yarn industries, where reliable measurement of parameters related to processing harmful substances needs to be examined. Such findings can be cumulated using smart assessment like life cycle analysis. The ecological impact category, supply chain, and climate-changing factors were considered for the necessary assessment.

This paper applies the Life Cycle Assessment technique in the textile and yarn industry to estimate critical environmental potentials. The critical input for the fabric and yarn industry was put in the GaBi software model to estimate various environmental potentials.

Global warming potential, electricity, and raw cotton consumption in the fabric and yarn industry were critical concerns where attention should be focused on minimizing environmental potentials from cradle to gate assessment.

This qualitative study is made via the industry case-wise inputs and outputs, which can vary with demographic conditions. Some machine and human constraints have not been implemented in modelling life cycle model for smart simulation. Smart simulation helps in linking different parameters and simulates their combined effects on the product life cycle.

This modelling approach will help access pollution constituents in different supply chain production processes and optimize them simultaneously.

The raw data used in this analysis are collected from an Indian small scale textile industry. In the textile fabrication industry, earlier assessments were carried out in cotton generation, impact of PET, cradle to grave assessment of textile products and garment processing only. In this research the smart model is drawn to consider each input parameter of yarn and textile fabric to determine the criticality of each input in this assessment. This article mainly talks about life cycle and circular supply assessment applied to first time for both cotton to yarn processing and yarn to fabric industry for necessary estimation of environment potentials.

The purpose of this research is to address the existing gap in the study of construction and demolition waste (C&DW) by focusing on its impact on human health throughout the entire life cycle. And this research provides a comprehensive assessment model that incorporates the release of gaseous pollutants and particulate matter during the whole life cycle of C&DW, thereby contributing to a more holistic understanding of its impact on human health.

The research was conducted in two stages. Firstly, the quantitative model framework of pollutants emitted by C&DW was established. Three types of pollutants were considered, namely nitrogen dioxide (NO₂), sulfur dioxide (SO₂) and inhalable particulate matter (PM10). Second, disability-adjusted life year (DALY) and willingness to pay (WTP) assessments were used to provide a monetary quantified health impact for pollutants released by C&DW.

The results show that the WTP value of PM10 is the highest among all pollutants and 8.68E+07 dollars/a, while the WTP value in the disposal stage accounts for the largest proportion compared to the generation and transportation stage. These findings emphasize the importance of PM10 and C&DW treatment stage for pollutant treatment.

The results of this study are of great significance for the management department to optimize the construction management scheme to reduce the total amount of pollutants produced by C&DW and its harm to human health. Meanwhile, this study fills the gap in existing research on the impact assessment of C&DW on human health throughout the whole life cycle, and provides reference and basis for future research and policy formulation.

Construction industry is one of the leading causes of pollution generation in today's context. But the fact that the development of construction industry leads to the country's economic and social development cannot be unobserved. Hence, there is a need to develop a sustainable construction methodology, and while doing so, measures must be considered so as to not disturb the natural habitats. With the greater prominence shown toward the concept of green and sustainable construction developments, various tools have been developed in recent years in order to measure the performance of such sustainable and green buildings. In the Indian context, the assessment tools developed to measure the performance of the green building are found to be scanty in addressing various economic and social impacts.

This study aims at developing a building performance score (BPS) model concerning the sustainability model built on the triple bottom priorities considering all the three vital components, viz. environmental, economic and social factors. In this study, the different phases involved in the complete life cycle of the project are recognized and then all the phases are assessed considering all the three major components mentioned in the BPS model.

The outcome of this study specifies that various indicators, such as the topographical and climate change, health and safety of the construction workers, project management consultancy, risk management, security measures and solid waste management, form a chief source of a sustainable building, and these indicators are not being assessed in the existing assessment tools. Also, consideration of environmental, economic and social factors is also equally important in construction industry. Moreover, these indicators are also required to be assessed and included in the evaluation process while assessing the performance of the building.

The BPS model developed in the study will assist to improve in assessing the building performance with respect to all indicators in the complete life cycle of the project.

Recently, there has been a shift toward the embodied energy assessment of buildings. However, the impact of material service life on the life-cycle embodied energy has received little attention. We aimed to address this knowledge gap, particularly in the context of the UAE and investigated the embodied energy associated with the use of concrete and other materials commonly used in residential buildings in the hot desert climate of the UAE.

Using input–output based hybrid analysis, we quantified the life-cycle embodied energy of a villa in the UAE with over 50 years of building life using the average, minimum, and maximum material service life values. Mathematical calculations were performed using MS Excel, and a detailed bill of quantities with >170 building materials and components of the villa were used for investigation.

For the base case, the initial embodied energy was 57% (7390.5 GJ), whereas the recurrent embodied energy was 43% (5,690 GJ) of the life-cycle embodied energy based on average material service life values. The proportion of the recurrent embodied energy with minimum material service life values was increased to 68% of the life-cycle embodied energy, while it dropped to 15% with maximum material service life values.

The findings provide new data to guide building construction in the UAE and show that recurrent embodied energy contributes significantly to life-cycle energy demand. Further, the study of material service life variations provides deeper insights into future building material specifications and management considerations for building maintenance.

Enhancing sustainability of the supply process of construction materials is challenging and requires accounting for a variety of environmental and social impacts on top of the traditional, mostly economic, impacts associated with a particular decision involved in the management of the supply chain. The economic, environmental, and social impacts associated with various components of a typical supply chain are highly sensitive to project and market specific conditions. The purpose of this paper is to provide decision makers with a methodology to account for the systematic trade-offs between economic, environmental, and social impacts of supply decisions.

This paper proposes a novel framework for sustainability assessment of construction material supply chain decisions by taking advantage of the information made available by customized building information models (BIM) and a number of different databases required for assessment of life cycle impacts.

The framework addresses the hierarchy of decisions in the material supply process, which consists of four levels including material type, source of supply, supply chain structure, and mode of transport. The application is illustrated using a case study.

The proposed framework provides users with a decision-making method to select the most sustainable material alternative available for a building component and, thus, may be of great value to different parties involved in design and construction of a building. The multi-dimensional approach in selection process based on various economic, environmental, and social indicators as well as the life cycle perspective implemented through the proposed methodology advocates the life cycle thinking and the triple bottom line approach in sustainability. The familiarity of the new generation of engineers, architects, and contractors with this approach and its applications is essential to achieve sustainability in construction.

A decision-making model for supply of materials is proposed by integrating the BIM-enabled life cycle assessment into supply chain and project constraints management. The integration is achieved through addition of a series of attributes to typical BIM. The framework is supplemented by a multi-attribute decision-making module based on the technique for order preference by similarity to ideal solution to account for the trade-offs between different economic and environmental impacts associated with the supply decisions.