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Accounting’s definition of accountability should include attributes of socioenvironmental degradation manufactured by unsustainable technologies. Beck argues that emergent accounts should reflect the following primary characteristics of technological degradation: complexity, uncertainty, and diffused responsibility. Financial stewardship accounts and probabilistic assessments of risk, which are traditionally employed to allay the public’s fear of uncontrollable technological hazards, cannot reflect these characteristics because they are constructed to perpetuate the status quo by fabricating certainty and security. The process through which safety thresholds are constructed and contested represents the ultimate form of socialized accountability because these thresholds shape how much risk people consent to be exposed to. Beck’s socialized total accountability is suggested as a way forward: It has two dimensions, extended spatiotemporal responsibility and the psychology of decision-making. These dimensions are teased out from the following constructs of Beck’s Risk Society thesis: manufactured risks and hazards, organized irresponsibility, politics of risk, radical individualization and social learning. These dimensions are then used to critically evaluate the capacity of full cost accounting (FCA), and two emergent socialized risk accounts, to integrate the multiple attributes of sustainability. This critique should inform the journey of constructing more representative accounts of technological degradation.

Numerous metals can be processed using the additive manufacturing process laser-based powder bed fusion of metals (PBF-LB/M, ISO/ASTM 52900). The main advantages of additive manufacturing technologies are the high degree of design freedom and the cost-effective implementation of lightweight structures. This could be profitable for gears with increased power density, combining reduced mass with considerable material strength. Current research on additively manufactured gears is focused on developing lightweight structures but is seldom accompanied by simulations and even less by mechanical testing. There has been very little research into the mechanical and material properties of additively manufactured gears. The purpose of this study is to investigate the behavior of lightweight structures in additively manufactured gears under static loads.

This research identifies the static load-carrying capacity of helical gears with different lightweight structures produced by PBF-LB/M with the case hardening steel 16MnCr5. A static gear loading test rig with a maximum torque at the pinion of T₁ = 1200 Nm is used. Further focus is set on analyzing material properties such as the relative density, microstructure, hardness depth profile and chemical composition.

All additively manufactured gear variants show no failure or plastic deformation at the maximum test load. The shaft hub connection, the lightweight hub designs and the gearing itself are stable and intact regarding their form and function. The identified material characteristics are comparable to conventionally manufactured gears (wrought and machined), but also some particularities were observed.

This research demonstrates the mechanical strength of lightweight structures in gears. Future research needs to consider the dynamic load-carrying capacity of additively manufactured gears.

This paper aims to examine general contractors’ experiences of using off-site manufactured structural framing systems. This engaged a single-case study using a qualitative methodology to identify expected benefits, actual benefits and challenges of such systems.

A single-case study approach evaluated general contractors’ experience of using a manufactured structural framing system. Qualitative data were collated and analyzed from industry domain experts to determine commonalities and thematic thinking.

The study revealed that the reasons behind considering off-site building systems were: accelerating the project schedule, overcoming site constraints and having a better end-product. The top expected benefits were: saving time (schedule), saving cost and improving quality. The top actual observed benefits were: saving erection time, reducing waste generation, reducing project costs, reducing safety risks and improving construction site logistics. The main challenges encountered were: unfamiliarity of different project parties with the off-site framing system, difficulty with reducing the overall project schedule, heavy site logistics and complicated off-site system design and standards requirements. The findings include solutions to overcome the challenges associated with using a manufactured structural system.

This paper was a case study and therefore inherently limited in its generalizability. The study was conducted with general contractors in the mountain-west region of the USA. However, the implications of the study may have a broad application, as contractors across the globe seek to find similar solutions to using off-site or manufactured construction methods.

Construction labor shortages around the world are forcing the construction industry to find creative solutions to meet the demand for their services. Manufactured or off-site construction methods provide a possible solution to that labor shortage. However, builders need to be aware of the immediate challenges and actual benefits of using a manufactured structural framing system.

Manufactured structural framing systems have the potential to impact lean and sustainable practices in construction. Reduced waste, reduced on-site man-power requirements, reduced construction schedules and reduced injuries each improve the lives of construction workers and the communities around these buildings.

An extensive literature review was performed to guide the design of this case study. Much has been written about off-site construction practices, but there is a significant research gap on the topic of structural framing systems. This study contributes to expanding the knowledge of off-site construction and specifically helps researchers and practitioners understand the challenges and benefits of this systematic approach to construction.

The purpose of this paper is to explore the current state of popular modern methods of construction (MMC) and pre-manufactured construction in the construction industry and propose a framework for future implications for practice and future research.

This technical paper is based on a narrative review of the extant literature on the subject. First, the Scopus search engine was used to retrieve relevant papers on MMC, offsite and pre-manufactured construction. Second, institutional literature such as reports by industry professional and trade bodies, literature from leading technology firms and contractors with experience of MMC were extracted. These two strands of literature were synthesised and a comprehensive discussion on the topic was provided.

Results show that journal publications on MMC and pre-manufactured construction have increased in the past decade. The paper found significant advances in the development of premanufactured and offsite construction approaches with many benefits. Offsite and pre-manufactured construction are viable and sustainable systems currently suitable for wider adoption as the mainstream construction method.

This technical paper based on an integrative review of relevant literature could have benefitted from interviews of professionals with experience of offsite and pre-manufacture techniques and from wider availability of current academic publications on the subject. Validation of the framework has not been undertaken.

Not much-published work has been undertaken on the current state of development globally and the viability of these construction approaches. This paper evaluates evidence from academic and industry sources to address this gap. A framework has been developed which can help the industry’s industrialisation drive.

Honeycomb cellular structures exhibit unique mechanical properties such as high specific strength, high specific stiffness, high energy absorption and good thermal and acoustic performance. This paper aims to use numerical modeling to investigate the effective elastic moduli, in-plane and out-of-plane, for thick-walled honeycombs manufactured using selective laser melting (SLM).

Theoretical predictions were performed using homogenization on a sample scale domain equivalent to the as-manufactured dimensions. A Renishaw AM 250 machine was used to manufacture hexagonal honeycomb samples with wall thicknesses of 0.2 to 0.5 mm and a cell size of 3.97 mm using 304 L steel powder. The SLM-manufactured honeycombs and cylindrical test coupons were tested using flatwise and edgewise compression. Three-dimensional finite element and strain energy homogenization were conducted to determine the effective elastic properties, which were validated by the current experimental outcomes and compared to analytical models from the literature.

Good agreement was found between the results of the effective Young’s moduli ratios numerical modeling and experimental observations. In-plane effective elastic moduli were found to be more sensitive to geometrical irregularity compared to out-of-plane effective moduli, which was confirmed by the analytical models. Also, it was concluded that thick-walled SLM manufactured honeycombs have bending-dominated in-plane compressive behavior and a stretch-dominated out-of-plane compressive behavior, which matched well with the simulation and numerical models predictions.

This work uses three-dimensional finite element and strain energy homogenization to evaluate the effective moduli of SLM manufactured honeycombs.

The purpose of this paper is to establish manufactured construction as a good potential alternative to meet the growing housing needs of China.

The paper uses literature review and case study as research methodologies. Literature review is used to identify the need for housing and establish the manufacturing prowess of China. The case study is used to look at how a similar problem has been tackled in the UK and then the case study findings are used to identify future direction for China.

Findings suggest that there is an acute shortage of housing in China, and at the same time the manufacturing sector in China is very strong. Therefore, in order to meet the housing demand for the population, manufactured construction offers a very attractive and cost‐efficient alternative.

Manufactured construction is an attractive alternative for China and therefore the government needs to encourage this sector through subsidies and tax benefits. Given that currently China is regarded as a manufacturing powerhouse, it will be relatively easy to establish manufactured construction as an organised and supported sector by the government.

The paper presents manufactured construction as an attractive alternative and strategic direction that China should adopt to meet the growing housing needs of the citizens. This also would appear to be an obvious alternative, given the manufacturing capabilities of China.

This study aims to evaluate and assess the elastoplastic properties of Ti-6Al-4V alloy manufactured by Arcam Q20 Plus electron beam melting (EBM) machine by a tensile test campaign and micro computerized tomography (microCT) imaging.

ASTM E8 tensile test specimens are designed and manufactured by EBM at an Arcam Q20 Plus machine. Surface quality is improved by machining to discard the effect of surface roughness. After surface machining, hot isostatic pressing (HIP) post-treatment is applied to half of the specimens to remove unsolicited internal defects. ASTM E8 tensile test campaign is carried out simultaneously with digital image correlation to acquire strain data for each sample. Finally, build direction and HIP post-treatment dependencies of elastoplastic properties are analyzed by F-test and t-test statistical analyses methods.

Modulus of elasticity presents isotropic behavior for each build direction according to F-test and t-test analysis. Yield and ultimate strengths vary according to build direction and post-treatment. Stiffness and strength properties are superior to conventional Ti-6Al-4V material; however, ductility turns out to be poor for aerospace structures compared to conventional Ti-6Al-4V alloy. In addition, micro CT images show that support structure leads to dense internal defects and pores at applied surfaces. However, HIP post-treatment diminishes those internal defects and pores thoroughly.

As a novel scientific contribution, this study investigates the effects of three orthogonal build directions on elastoplastic properties, while many studies focus on only two-build directions. Evaluation of Poisson’s ratio is the other originality of this study. Furthermore, another finding through micro CT imaging is that temporary support structures result in intense defects closer to applied surfaces; hence high-stress regions of structures should be avoided to use support structures.

Because of the anisotropy of the process and the variability in the quality of printed parts, finite element analysis is not directly applicable to recycled materials manufactured using fused filament fabrication. The purpose of this study is to investigate the numerical-experimental mechanical behavior modeling of the recycled polymer, that is, recyclable polyethylene terephthalate (rPET), manufactured by a deposition FFF process under compressive stresses for new sustainable designs.

In all, 42 test specimens were manufactured and analyzed according to the ASTM D695-15 standards. Eight numerical analyzes were performed on a real design manufactured with rPET using Young's compression modulus from the experimental tests. Finally, eight additional experimental tests under uniaxial compression loads were performed on the real sustainable design for validating its mechanical behavior versus computational numerical tests.

As a result of the experimental tests, rPET behaves linearly until it reaches the elastic limit, along each manufacturing axis. The results of this study confirmed the design's structural safety by the load scenario and operating boundary conditions. Experimental and numerical results show a difference of 0.001–0.024 mm, allowing for the rPET to be configured as isotropic in numerical simulation software without having to modify its material modeling equations.

The results obtained are of great help to industry, designers and researchers because they validate the use of recycled rPET for the ecological production of real-sustainable products using MEX technology under compressive stress and its configuration for numerical simulations. Major design companies are now using recycled plastic materials in their high-end designs.

Validation results have been presented on test specimens and real items, comparing experimental material configuration values with numerical results. Specifically, to the best of the authors’ knowledge, no industrial or scientific work has been conducted with rPET subjected to uniaxial compression loads for characterizing experimentally and numerically the material using these results for validating a real case of a sustainable industrial product.

This paper aims to describe the obtainment of Ti-6Al-4V parts with a hierarchical arrangement of pores by additive manufacturing, aiming at designing orthopedic implants.

The experimental methodology compares microstructural and mechanical properties of Menger pre-fractal sponges of Ti-6Al-4V alloy, manufactured by laser powder bed fusion (LPBF) and electron beam powder bed fusion (EBPBF), with three different porosity volumes. The pore arrangement followed the formation sequence of the Menger sponge, with hierarchical order from 1 to 3.

The LPBF parts presented a martensitic microstructure, while the EBPBF parts presented an α + ß microstructure, independently of its wall thickness. The LPBF parts presented higher mechanical resistance and effective stiffness than the EBPBF parts with similar porosity volume. The stiffness values of the Menger pre-fractal sponges of Ti-6Al-4V alloy, between 4 and 29 GPa, are comparable to those of the cortical bone. Furthermore, the deformation behavior presented by the Menger pre-fractal sponges of Ti-6Al-4V alloy did not follow the Gibson and Ashby model's prediction.

To the best of the authors' knowledge, this is the first study to obtain Menger pre-fractal sponges of Ti-6Al-4V alloy by LPBF and EBPBF. The deformation behavior of the obtained porous parts was contrasted with the Gibson and Ashby model's prediction.

The purpose of the paper is to determine why premature deindustrialization is occurring in many developing countries.

A theoretical structure for explaining premature deindustrialization is utilized. Then the comparative experiences of a number of developing countries are used to illustrate the operation of the theory.

The results indicate that increasing inequality among a number of developing countries has reduced the domestic market for labor intensive manufactured goods, resulting in stagnation in manufacturing. Also, the increasing inequality in developed countries has reduced international demand for labor intensive manufacturing. Thus developing countries have fewer opportunities to export labor intensive manufacturing.

Data on inequality is limited and it is very difficult to determine causality. However, intuition indicates that causality is most likely bi-directional.

Strategies of economic development must concern themselves with the effects that increasing inequality will likely have on the development of labor intensive manufacturing.

Social programs that bolster the purchasing power of poor families are likely to be important (social safety net). Broad-based agricultural growth will provide a basis for labor intensive manufacturing.

The originality stems from the linking of deindustrialization with rising inequality.