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1 – 10 of over 3000M. Grujicic, J.S. Snipes, S. Ramaswami, R. Yavari, C.-F. Yen and B.A. Cheeseman
The purpose of this paper is to address the problem of substitution of steel with fiber-reinforced polymer-matrix composite in military-vehicle hull-floors, and identifies and…
Abstract
Purpose
The purpose of this paper is to address the problem of substitution of steel with fiber-reinforced polymer-matrix composite in military-vehicle hull-floors, and identifies and quantifies the associated main benefits and shortcomings.
Design/methodology/approach
The problem is investigated using a combined finite-element/discrete-particle computational analysis. Within this analysis, soil (in which a landmine is buried), gaseous detonation products and air are modeled as assemblies of discrete, interacting particles while the hull-floor is treated as a Lagrangian-type continuum structure. Considerable effort has been invested in deriving the discrete-material properties from the available experimental data. Special attention has been given to the derivation of the contact properties since these, in the cases involving discrete particles, contain a majority of the information pertaining to the constitutive response of the associated materials. The potential ramifications associated with the aforementioned material substitution are investigated under a large number of mine-detonation scenarios involving physically realistic ranges of the landmine mass, its depth of burial in the soil, and the soil-surface/floor-plate distances.
Findings
The results obtained clearly revealed both the benefits and the shortcomings associated with the examined material substitution, suggesting that they should be properly weighted in each specific case of hull-floor design.
Originality/value
To the authors’ knowledge, the present work is the first public-domain report of the findings concerning the complexity of steel substitution with composite-material in military-vehicle hull-floors.
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Jason Martinez and Ann Jeffers
A methodology for producing an elevated-temperature tension stiffening model is presented.
Abstract
Purpose
A methodology for producing an elevated-temperature tension stiffening model is presented.
Design/methodology/approach
The energy-based stress–strain model of plain concrete developed by Bažant and Oh (1983) was extended to the elevated-temperature domain by developing an analytical formulation for the temperature-dependence of the fracture energy Gf. Then, an elevated-temperature tension stiffening model was developed based on the modification of the proposed elevated-temperature tension softening model.
Findings
The proposed tension stiffening model can be used to predict the response of composite floor slabs exposed to fire with great accuracy, provided that the global parameters TS and Kres are adequately calibrated against global structural response data.
Originality/value
In a finite element analysis of reinforced concrete, a tension stiffening model is required as input for concrete to account for actions such as bond slip and tension stiffening. However, an elevated-temperature tension stiffening model does not exist in the research literature. An approach for developing an elevated-temperature tension stiffening model is presented.
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Qizhu Yang, Kejian Ma, Huagang Zhang, Yanhui Wei and Ze Xiang
The purpose of this paper is to study the dynamic characteristics and seismic performance of the composite open-web grid floor structure.
Abstract
Purpose
The purpose of this paper is to study the dynamic characteristics and seismic performance of the composite open-web grid floor structure.
Design/methodology/approach
Studied by using mode-superposition response spectrum method and time history analysis method.
Findings
The results show that the vertical mode-superposition response spectrum method is close to the time history analysis method. The floor has strong seismic performance, and the deflection and internal force are not large under vertical seism. The vertical seismic action suggested that 10% of the representative value of gravity load should be used to ensure the safety of the structure.
Originality/value
In the design, the mid-span section should be properly strengthened or the variable section design should be adopted.
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Naveed Alam, Ali Nadjai, Chrysanthos Maraveas, Konstantinos Tsarvdaridis and Charles Kahanji
The purpose of this study is to investigate the effect of the airgap on thermal behaviour and structural response of fabricated slim floor beams (FSFBs) in fire.
Abstract
Purpose
The purpose of this study is to investigate the effect of the airgap on thermal behaviour and structural response of fabricated slim floor beams (FSFBs) in fire.
Design/methodology/approach
A detailed analytical model is established and validated by replicating the response of FSFBs. The validated finite element modelling method is then used to perform sensitivity analysis. First, the influence of the airgap presence is analysed, and later, the effect of the airgap size on thermal behaviour and structural response of FSFBs at elevated temperatures is investigated.
Findings
Results from the study demonstrate that the presence of the airgap has a considerable influence on their thermal behaviour and structural response of FSFBs. The size of the airgap, however, has no significant influence on their thermal and structural response in fire.
Originality/value
No investigations, experimental or analytical, are available in literature addressing the effect of airgap on the structural response of FSFBs in fire. The presence of airgap is helpful and beneficial; hence, the findings of this research can be used to develop designs for structural members with airgap as an efficient and inexpensive way to improve their response in fire.
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Naoya Yotsumoto, Takeo Hirashima and Koji Toyoda
This paper aims to investigate the fire performance of composite beams when considering the hogging moment resistance of the fin-plate beam-to-girder joints including the effect…
Abstract
Purpose
This paper aims to investigate the fire performance of composite beams when considering the hogging moment resistance of the fin-plate beam-to-girder joints including the effect of continuity of reinforcements.
Design/methodology/approach
Experiments on composite beams with fin-plate joints protected only at the beam ends are conducted. The test parameter is the specification of reinforcement, which affects the rotational restraint of the beam ends. In addition, a simple method for predicting the failure time of the beam using an evaluation model based on the bending moment resistance of the beam considering the hogging moment resistance of the fin-plate joint and the reinforcement is also presented.
Findings
The test results indicate that the failure time of the beam is extended by the hogging moment resistance of the joints. This is particularly noticeable when using a reinforcing bar with a large plastic deformation capability. The predicted failure times based on the evaluation method corresponded well with the test results.
Originality/value
Recent studies have proposed large deformation analysis methods using FEM that can be used for fire-resistant design of beams including joints, but these cannot always be applicable in practice due to the cost and its complexity. Our method can consider the hogging moment resistance of the joint and the temperature distribution in the axial direction using a simple method without requirement of FEM.
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Andrew P. McCoy, Ralph Badinelli, C. Theodore Koebel and Walid Thabet
This paper aims to report on data from case studies of development process, and a survey of use patterns over ten years, for 13 highly innovative products. While the paper does…
Abstract
Purpose
This paper aims to report on data from case studies of development process, and a survey of use patterns over ten years, for 13 highly innovative products. While the paper does not claim concurrent commercialization (CC) as a universal solution, it aims to highlight significant correlates between management best practice, concurrent commercialization and builder use rates for these 13 highly innovative products in the USA residential construction industry.
Design/methodology/approach
To study the effect of CC on new‐product adoption rates by installers, the authors assembled data from the National Association of Home Builders' (NAHB) Builders' Practices Survey (BPS) for the years 1996 through 2005. The data collection was executed in three phases. Best practices were collected from literature. Explanatory variables regarding best practice and presence of CC were collected and measured through case studies. The measure of market penetration, based on the concept of innovativeness, was obtained from the BPS survey data.
Findings
Data analysis of 13 highly innovative products indicates that CC is consistent with accepted best practice in product development. These products suggest that some organizations might contain 100 percent CC with varying degrees of best practice management ideals, and also include equilibrium.
Research limitations/implications
The extent to which products, with varying CC percentage, are affected by individual steps within CC is a direction for future research. The authors also did not have the ability to look at the entry year for other products strongly rooted in CC; there could be other explanations for a product entering the market strongly.
Practical implications
CC is essentially directed at designing a commercialization process, as opposed to designing a product, which benefits the product development from exposure to all members along the construction supply chain. CC, drawing on concurrent engineering, expands the definition of the market to include all supply‐chain participants, not just the installers and advocates the establishment of a complete supply chain, possible only if every member of the chain foresees net benefits to joining. In strengthening the commercialization process, the product might experience better probability of success.
Originality/value
The paper places reason upon product failure, in the residential construction industry, through further investigation of sound commercialization process.
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Yile Zhang, Yadong Zhou and Youchao Sun
The purpose of this paper is to analyze the bird impact damage of fuselage composite stiffened structures by numerical method and to evaluate the damage and the bird impact…
Abstract
Purpose
The purpose of this paper is to analyze the bird impact damage of fuselage composite stiffened structures by numerical method and to evaluate the damage and the bird impact resistance of different structures.
Design/methodology/approach
The deformation and damage of composite stiffened plates during bird impact are numerically analyzed by the explicit finite element software LS-DYNA. A comparative study on the numerical calculation results was conducted by using SPH (Smoothed Particle Hydrodynamics)-FEM (Finite Element Method) modeling and simulation. First, the I-shaped, T-shaped, straight stiffened plates and unstiffened plate were designed. Second, the accuracy of the bird model was verified and further used to evaluate bird strikes on composite stiffened plate. Third, the results of damage modes as well as displacements of the stiffened plates were compared.
Findings
The stiffeners can increase the local stiffness of the composite panel, which can effectively inhibit the bird’s movement along the impact direction. Adding stiffeners can change the panel matrix tension damage from global distribution to local distribution mode; however, the impact damage distribution and the ability to inhibit damage propagation can differ for different stiffened panels. Especially, the I-stiffened panel exhibits a better anti-bird strike performance.
Originality/value
The analysis of geometric parameters of structural components by numerical methods can reduce the cost of the design phase and has been widely used in aircraft design. The present study evaluated the bird impact damage of composite stiffened plates with different structures, which provides a guideline for selecting the stiffened plate structure in the fuselage skin.
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Sengkwan Choi, Faris Ali, Ali Nadjai, Sanghoon Han and Joungyoon Choi
This paper presents a numerical study to predict the in-fire performance of slim floor system, composed of asymmetric steel beam, deep steel decking and in-situ concrete slab. The…
Abstract
This paper presents a numerical study to predict the in-fire performance of slim floor system, composed of asymmetric steel beam, deep steel decking and in-situ concrete slab. The reliability of the proposed numerical model was verified by comparison with experimental results obtained for 4.2m beam tests. A pilot study was also conducted to examine the effect of the cross sectional modification of the steel section on performance enhancement of the model in fire.
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Kailash Choudhary, Narpat Ram Sangwa and Kuldip Singh Sangwan
This study aims to quantify and compare the environmental impacts of Marble-stone and Kota-stone flooring options widely used for buildings in India. The study discusses the…
Abstract
Purpose
This study aims to quantify and compare the environmental impacts of Marble-stone and Kota-stone flooring options widely used for buildings in India. The study discusses the possibility of carbon sequestration through Bamboo cultivation in India.
Design/methodology/approach
The study has followed a standard life cycle assessment (LCA) framework based on ISO 14040 guidelines. Three distinct phases have been compared on midpoint and endpoint assessment categories – raw material, polishing and disposal. Primary data has been collected from the construction site in India, and secondary data has been collected from the Ecoinvent 3.0 database. Previous studies have been referred to discuss and calculate the area of bamboo cultivation required to sequestrate the generated carbon from the flooring.
Findings
The study has found that endpoint category damage to resources, and midpoint categories of climate change, metal depletion and agricultural land use are highly impacted in building floorings. The study has also found that the Marble-stone floor generates higher environmental impacts than the Kota-stone floor in most of the midpoint and endpoint impact categories. This difference is significant in the raw material phase due to the different compositions of stones. The study also found that Bamboo has excellent potential to act as a carbon sink and mitigate the generated carbon.
Research limitations/implications
This study excludes human labour, cutting and distribution of floor tiles made of Marble-stone and Kota-stone. The researcher can use the study to evaluate, compare and benchmark the various building flooring options from the environmental perspective. The study aids to the body of knowledge available on the various building flooring options by presenting the LCA or the environmental impacts generated by two flooring options. It is expected that the architects and builders can use these results to develop carbon-neutral buildings. This study provides a methodology for governments, constructors, builders and individuals to evaluate, compare and benchmark the various construction materials from the environmental perspective by computing the environmental impacts throughout the life cycle of the materials.
Originality/value
This study compares two widely used building flooring options using the LCA methodology and evaluates the potential of bamboo cultivation near the buildings for carbon sinks. The study is unique because it shows the environmental impacts of two flooring options and the carbon sequestration method to mitigate/absorb the generated environmental impacts in or around the building itself through bamboo cultivation. This study may set the foundation for carbon-neutral buildings.
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Ting Luo, Xiaolong Xue, Yongtao Tan, Yuna Wang and Yuanxin Zhang
This paper aimed to introduce a systematic body of knowledge via a scientometric review, guiding the sustainable transition from conventional construction to prefabricated…
Abstract
Purpose
This paper aimed to introduce a systematic body of knowledge via a scientometric review, guiding the sustainable transition from conventional construction to prefabricated construction. The construction industry currently faces a challenge to balance sustainable development and the construction of new buildings. In this context, one of the most recent debates is prefabricated construction. As an emerging construction approach, although existing knowledge makes contributions to the implementation of prefabricated construction, there is a lack of a comprehensive and in-depth overview of the critical knowledge themes and gaps.
Design/methodology/approach
This study uses the scientometric analysis to review the state-of-the-art knowledge of prefabricated construction. It retrieved data from the Web of Science core collection database. CiteSpace software was used to conduct the analysis and visualization; three analysis methods identify the knowledge hotspots, knowledge domains and knowledge topics. Finally, according to integrating the hidden connections among results, a body of knowledge for prefabricated construction application can be inferred.
Findings
The results show that 120 knowledge hotspots, five critical knowledge domains and five prominent knowledge topics are vital for promoting implementation of prefabricated construction. Based on the afore analysis, a body of knowledge for prefabricated construction that can systematically cover a broad knowledge of prefabricated construction-related research and activities are integrated and proposed in this paper.
Originality/value
Body of knowledge systematically covers a broad knowledge of prefabricated construction applications and is vital to guide researchers and practitioners to conduct related research and activities, thereby promoting the sustainable transition to prefabricated construction implementation.
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