ORCID Profile
0000-0002-6212-9446
Current Organisation
Macquarie University
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Civil Engineering | Structural Engineering |
Publisher: Research Square Platform LLC
Date: 20-04-2020
Publisher: ISEC Press
Date: 07-2022
DOI: 10.14455/ISEC.2022.9(1).CSA-04
Abstract: Based on the data released by the Australian Bureau of Statistics, the number of injuries and fatalities caused by falls from height (FFH) accidents at construction sites is one of the highest making the construction industry relatively unsafe compared to other industries. This study has been made to find out the causes, consequences, and probabilities of construction fall incidents in New South Wales (NSW), Australia. The Bowtie (BT) diagram will be used to illustrate various accident situations in order to evaluate the risk of FFH in NSW, as it has not been used in previous studies. The BT diagram, which is made up of a fault tree (FT) and an event tree, represents the logical interconnections between the causes and consequences of the accidents (ET). FTs are used to calculate the odds of different accident situations. The ET analysis is then used to assess the various outcomes of these accidents, as well as their probabilities. Following that, the schematic modeling will be entered into GeNIe software for results validation, and sensitivity analysis will be used to find the main contributor of FFH incidents. The outcome will aid in the prevention of particular incidents and increase the overall level of safety on construction sites. Based on the data released by the Australian Bureau of Statistics, the number of injuries and fatalities caused by falls from height (FFH) accidents at construction sites is one of the highest, making the construction industry relatively unsafe compared to other industries. This study has been made to find out the most common causes, probabilities, and appropriate mitigation measures in construction fall incidents in New South Wales (NSW), Australia. The findings obtained from NSW Construction Blitz in 2019 was used to analyze the probability of the common potential causes of falling from ladders, voids and edges, scaffolds, formworks and, mobile scaffolds and fall restraints. Five fault tree (FT) diagrams were used to illustrate various accident causes in order to determine the probability of risk of FFH in NSW. Following that, a schematic modeling was entered into Genie software for results validation and to determine the main contributor of FFH incidents. From this study, falling from voids and edges has the highest likelihood of falls in NSW with a probability of 27.15%. This is followed by falling from mobile scaffolds and fall restraints with 7.92%, which is closely followed by falling from scaffolds with 7.68%. While falling from ladders and falling from formworks were not too far behind, with 2.17% and 1.05% respectively. Preventative measures were then discussed for FFH accident scenarios. These findings will aid in the prevention of particular incidents and increase the overall level of safety on construction sites in NSW.
Publisher: MDPI AG
Date: 03-12-2019
DOI: 10.3390/MA12234015
Abstract: This paper presents a study of parameters affecting the fibre pull out capacity and strain-hardening behaviour of fibre-reinforced alkali-activated cement composite (AAC). Fly ash is a common aluminosilicate source in AAC and was used in this study to create fly ash based AAC. Based on a numerical study using Taguchi’s design of experiment (DOE) approach, the effect of parameters on the fibre pull out capacity was identified. The fibre pull out force between the AAC matrix and the fibre depends greatly on the fibre diameter and embedded length. The fibre pull out test was conducted on alkali-activated cement with a capacity in a range of 0.8 to 1.0 MPa. The strain-hardening behaviour of alkali-activated cement was determined based on its compressive and flexural strengths. While achieving the strain-hardening behaviour of the AAC composite, the compressive strength decreases, and fine materials in the composite contribute to decreasing in the flexural strength and strain capacity. The composite critical energy release rate in AAC matrix was determined to be approximately 0.01 kJ/m 2 based on a nanoindentation approach. The results of the flexural performance indicate that the critical energy release rate of alkali-activated cement matrix should be less than 0.01 kJ/m 2 to achieve the strain-hardening behaviour.
Publisher: MDPI AG
Date: 19-06-2021
DOI: 10.3390/APP11125675
Abstract: Current silo analysis and design methods developed from Janssen’s theory focus mainly on the flow of the granules inside the silo by assuming that the overall silo structure is infinitely rigid. A silo structure during discharge is technically a time varying mass dynamic problem, where the properties of the overall silo structure and the discharge rate and material properties also contribute to the development of the load. The physics of a silo system requires equilibrium between the granules inside the silo, the silo structure as a whole and the surrounding air. The established scientific principles and experimental data require fulfilling such equilibrium to accurately predict the dynamic loads during discharge. This correspondence explains how the equilibrium between the granules inside the silo, the silo structure as a whole and the surrounding air can be achieved to better predict and control the dynamic loads generated by the silo discharge process.
Publisher: Elsevier BV
Date: 05-2019
Publisher: Elsevier BV
Date: 04-2022
Publisher: ISEC Press
Date: 12-2018
DOI: 10.14455/ISEC.RES.2018.132
Abstract: Tensile properties are important for predicting tensile stress which causes thermal cracking. Fly ash, a by-product from coal-fired power plants, has been recently used to reduce such thermal cracks. However, investigations dealing with tensile properties of fly ash concrete are still limited. This study focuses on the tensile properties of concrete mixed with fly ash at an early age. Fly ash was mixed in general purpose concrete with a cement-replacement ratio of 20% by mass to simulate fly ash concrete used in Japan. To examine tensile Young's modulus and tensile creep, direct tension test was conducted using dog-bone shaped specimens. The tensile creep tests were conducted at the age of 3 days or 7 days, and the loading (30% of splitting tensile strength at the loading age) was sustained for 14 days. Past investigations usually assumed a constant elastic strain during creep test. It should be noted however that elastic strain at early age decreases with the age of concrete as hydration continues. This study takes a consideration of Young's modulus development during creep test to distinguish actual creep and elastic strains. Test results show that creep strain has been underestimated when assuming constant elastic strain.
Publisher: Elsevier BV
Date: 07-2019
Publisher: ISEC Press
Date: 12-2018
DOI: 10.14455/ISEC.RES.2018.130
Abstract: Extensive research has been conducted on the use of fly ash as a partial replacement of cement in order to promote the sustainable use of cement. Most of these research has focused on the investigation of the cementitious properties of the blended cement and the engineering properties of the end products, such as fly ash concrete. The sustainability benefit of using fly ash is often qualitatively perceived without any quantitative assessment. A recent study on the performance of hybrid polyvinyl alcohol fibre-reinforced ferrocement (HPVAF) shows that adding moderate amounts of fly ash in the mixes could maintain the ultimate flexure and tensile strength of HPVAF. The increased service life/durability and the use of FA up to a 25% replacement for cement in HPVAF not only conserve virgin resources for producing energy-intensive construction materials but also avoid associated environmental impacts due to the manufacturing of these materials. This certainly offers socio-economic benefits in terms of cost saving, enhance affordability and guaranteed material supply for the people both in current and future generations. Life cycle sustainability assessment (LCSA) was conducted to determine these triple bottom line benefits associated with the use of HPVAF and FA in building construction.
Publisher: Elsevier BV
Date: 11-2017
Publisher: Wiley
Date: 16-02-2016
DOI: 10.1002/FAM.2296
Publisher: MDPI AG
Date: 10-09-2022
DOI: 10.3390/BUILDINGS12091420
Abstract: Defining the damage and deflection from impact by using only the impact energy could be misleading due to the effect of impact momentum. In addition, reinforced concrete columns might be subjected to repeated impact loading. Hence, this study presents the numerical simulation of 16 RC columns with identical sizing and reinforcement details, subjected to equal energy-double impact loadings using a free-falling mass at midspan. The impact energy was kept constant for both impacts. For each analysis, the impact momentum was varied by varying the velocity and mass of the impactor. The axial load ratios of the columns are between 0.0 to 0.3 of the compressive strength of the concrete cross-section. The results clearly addressed the momentum effect on the impact responses. The momentum level affected the specimens’ damage behavior under the same input impact energy. A high momentum impact yielded more global flexural damage with large deflection, and a low momentum impact produced more local damage with a slight deflection. The axial load helps maintain the impact resistance capacity. However, the failure determined by the flexural damage pattern under the first impact was changed when subjected to the second impact to the shear mode with the presence of axial load. Further, the colliding index considering the momentum was used in the deflection prediction equation. The proposed equation improved the deflection calculation accuracy of reinforced concrete beams under equal energy but different momentum impact.
Publisher: SAGE Publications
Date: 10-2012
DOI: 10.1260/1369-4332.15.10.1705
Abstract: A new lightweight sandwich reinforced concrete (LSRC) section has been developed using prefabricated autoclaved aerated concrete (AAC) blocks as infill in the section where concrete is considered ineffective under bending. This paper presents an investigation into the strength and behaviour of LSRC slabs subjected to shear. Eight tests were conducted on four slabs, one solid and three different types of LSRC slabs. Based on the test results, all LSRC slabs exhibited similar behaviour to the equivalent solid slab and had varying shear capacities depending on the profile of AAC blocks infill. The obtained shear capacities were compared with the design values based on several major design codes and found to be within the safety predictions of the codes. ANSYS was employed to develop nonlinear finite element models of LSRC slabs. The numerical results agree well with the experimental one.
Publisher: ISEC Press
Date: 12-2018
DOI: 10.14455/ISEC.RES.2018.98
Abstract: Initial cracks due to volume changes at an early age affect the durability of concrete structures, so numerical simulations are often conducted in order to predict cracks. Such prediction requires some mechanical properties of early age concrete. Tensile Young's modulus is directly dependent on the prediction of tensile stress and is one of the important input data for FEM analysis. However, direct tension test for tensile Young's modulus needs a unique apparatus and specimen, and such test is not suitable for evaluating Young's modulus at early ages of concrete. The present study compared tensile Young's modulus with compressive Young's moduli of Fly ash concrete. Compressive Young's moduli used in this study were secant modulus and initial tangent modulus. In addition, linear modulus taken from a regression line of a compressive stress-strain curve in the range of stresses less than the splitting tensile strength was also evaluated. It is found that the secant modulus, which is generally used as Young's modulus in Japan was clearly smaller than the tensile Young's modulus, which means that, tensile stresses evaluated using a secant modulus might be underestimated. On the other hand, linear modulus and initial tangent modulus were almost equal to the tensile Young's modulus. This result indicates that tensile stresses can be evaluated using Young's modulus obtained from a compression test with general apparatus and specimens.
Publisher: Ital Publication
Date: 2023
DOI: 10.28991/CEJ-2023-09-01-02
Abstract: The frequencies of time-varying mass systems have not been commonly studied in engineering structures as the rate of mass change is generally small compared to the mass of the overall structure. For silos of granular materials, the total mass of the stored granules can be relatively high compared to the mass of the silo structure. During the flow-in or flow-out of granules, the silo system behaves as a time-varying mass system. Minor changes to the moisture content ratio of the granules can cause their flow characteristics to change. The influence of the moisture content ratio of the granular material inside a cylindrical silo is investigated in this paper using Variational Mode Decomposition, Hilbert Transform, and Hilbert Marginal Spectrum processing methods. The results show that the litude and frequency of vibration vary with the change in the moisture content ratio of the stored materials and across different cycles, despite all influencing parameters being kept constant. Such variations in the response of the structure mean that the loads also vary according to the principles of engineering mechanics. The outcomes of this research can be further developed into a diagnostic tool to conditionally monitor the structural integrity of the overall silo structure and flow characteristics automatically. Doi: 10.28991/CEJ-2023-09-01-02 Full Text: PDF
Publisher: MDPI AG
Date: 25-11-2021
Abstract: Adding fibers to concrete helps enhance its tensile strength and ductility. Synthetic fibres are preferable to steel ones which suffer from corrosion that reduces their functionality with time. More consideration is given to synthetic fibres as they can be sourced from waste plastics and their incorporation in concrete is considered a new recycling pathway. Thus, this work investigates the potential engineering benefits of a pioneering application using extruded macro polyfibres in concrete. Two different fiber dosages, 4 kg/m3 and 6 kg/m3, were used to investigate their influence based on several physical, mechanical and microstructural tests, including workability, compressive strength, modulus of elasticity, splitting-tensile strength, flexural test, CMOD, pull-out test and porosity. The test results revealed a slight decrease in the workability of the fibre-reinforced concrete, while all the mechanical and microstructural properties were enhanced significantly. It was observed that the compressive, splitting tensile and bonding strength of the concrete with 6 kg/m3 fibre dosage increased by 19.4%, 41.9% and 17.8% compared to the plain concrete specimens, respectively. Although there was no impact of the fibres on the modulus of rupture, they significantly increased the toughness, resulting in a progressive type of failure instead of the sudden and brittle type. Moreover, the macroporosity was reduced by the fibre addition, thus increasing the concrete compressive strength. Finally, simplified empirical formulas were developed to predict the mechanical properties of the concrete with fibre addition. The outcome of this study will help to increase the implementation of the recycled plastic waste in concrete mix design and promote a circular economy in the waste industry.
Publisher: Elsevier BV
Date: 05-2023
Publisher: Elsevier BV
Date: 10-2020
Publisher: Academic Journals
Date: 23-10-2012
DOI: 10.5897/SRE12.138
Publisher: ISEC Press
Date: 11-2015
DOI: 10.14455/ISEC.RES.2015.208
Abstract: This paper presents findings of an investigation into benefits of using Building Information Modelling (BIM) in construction projects. The research methodology includes a review of BIM development and achievement in construction industry, questionnaire survey, interview, and content analysis of secondary data. Data was collected and analyzed to identify the various benefits reflected from BIM implementation in addressing common problems experienced by the construction industry. The review and survey results indicate that a high frequency of occurrence of time and cost overruns occur in construction projects. Contributing factors were mainly rework, poor planning, documents delivery and approval, constructability issues, resources and weather condition. While some of the factors were unpreventable, BIM could be used as a tool to eliminate problems causing time and cost overruns. Various project benefits have been reflected through the content analysis of project case studies. It was found that time was the most positively influenced by the use of BIM followed by coordination, procurement, communication, cost and change of scope of the project, and lastly, risk.
Publisher: CRC Press
Date: 26-11-2012
DOI: 10.1201/B15320-64
Publisher: CRC Press
Date: 26-11-2012
DOI: 10.1201/B15320-65
Publisher: Elsevier BV
Date: 02-1996
Publisher: American Society of Civil Engineers (ASCE)
Date: 09-2016
Publisher: MDPI AG
Date: 17-11-2022
DOI: 10.3390/INFRASTRUCTURES7110156
Abstract: According to Modified Compression Field Theory (MCFT), the ultimate shear capacity of a reinforced concrete section depends on load effects (shear, moment, torsion, and axial force) caused by factored design loads. In many design standards, including Australian AS 5100.7, MCFT has been incorporated for bridge assessment, which requires a load rating to be carried out according to the loading of the nominated rating vehicle as prescribed in the standard. Recently, some approaches have been proposed for bridge load rating that have suggested using an iterative-search procedure to determine the shear capacity by proportionally increasing the load effects until the shear capacity and shear are equal. This paper describes several adverse effects of using the proportional load, which is not consistent with the characteristic of the vehicle loading, to determine the shear capacity for load rating. Numerical ex les of two bridge beams, one simply supported and the other continuous, are presented to demonstrate that the characteristic of the load effects caused by a moving vehicle is not representable by proportional load effects. Furthermore, the current practice in the bridge load rating does not load rate the longitudinal steel capacity in resisting the axial force induced by the load effects of the rating vehicle. This paper presents a new approach to the load rating that separately accounts for the load effect for axial failure mode of the longitudinal steel. Finally, it is pointed out that locating the critical section where the rating factor is minimum is tedious but can be automated by integrating load rating into the analysis of load effects.
Publisher: Informa UK Limited
Date: 1995
Publisher: Wiley
Date: 12-02-2014
DOI: 10.1002/FAM.2240
Publisher: ISEC Press
Date: 07-2022
DOI: 10.14455/ISEC.2022.9(1).SUS-05
Abstract: Green building rating systems are proving to be an effective way to encourage sustainability practices in the construction industry. Green Building Council of Australia (GBCA) has developed four Green Star rating tools that provide a means of certification for building design and construction, operation, fit outs, and communities. The GBCA Green Star rating gives credit to different sustainability aspects of buildings such as energy use in terms of greenhouse gas emissions, embodied energy of materials, water efficiency, and others. This study aimed at determining trends in sustainability practices in the Australian construction industry based on the Green Star credits of certified buildings under the Design and As-built tool. A frequency analysis on the points earned on credits versus the number of projects was done to show perspectives in the industry practice. Analysis of the Green Star credits was also carried out using data available in the literature to further understand the industry motives behind the results. Findings showed that “greenhouse gas emissions”, “indoor pollutants-engineered wood products”, “peak electricity demand reduction”, “potable water” and “sustainable transport” were the credits in which most of the rated buildings had achieved, while life cycle impacts were the credits that certified buildings rarely achieved.
Publisher: Inderscience Publishers
Date: 2019
Publisher: Ess & Ess Research Publications
Date: 15-09-2014
Publisher: ISEC Press
Date: 11-2014
DOI: 10.14455/ISEC.RES.2014.66
Abstract: This paper is part of an experimental series to investigate the potential use of ferrocement panels as a permanent form of reinforced concrete slabs with lightweight blocks infill. The ferrocement panels used are engineered with polyvinyl alcohol (PVA) fiber to have a strain hardening which can be characterized as high-performance fiber-reinforced cementitious composite (HPFRCC), called Engineered Ferrocement (EF). In the experimental work, ferrocement control panels and hybrid ferrocement panels were tested for strength capacity and hard strain behavior through flexure, toughness, and multitrack forming. The results showed that by using the ideal fiber/wire mesh content, the hybrid ferrocement panels act as a strain-hardening cementitious material, and successfully increasing the flexure strength compared to the control-group ferrocement. The initial investigation indicates that hybrid PVA fiber ferrocement in tensile zones can be successfully used as permanent form.
Publisher: Wiley
Date: 03-05-2016
DOI: 10.1002/FAM.2365
Publisher: Thomas Telford Ltd.
Date: 11-2019
Abstract: Substantial damage to buildings from seismic pounding is the result of earthquakes in many urban areas. This study investigated the effects of pounding in low-rise buildings, which had been in idually designed for seismic resistance, using a three-dimensional numerical model. The pounding between the heavier and lighter buildings was conducted for four cases with floor to floor collision and zero separation gap the total heights of the buildings were varied. The ratio of the storey mass between the heavier to the lighter buildings in all cases was 1·7. The results demonstrated that the heavier buildings were almost unaffected by the collision, and that seismic design without consideration of pounding is acceptable. However, the pounding had more influence on lighter buildings. A significant increase of inter-storey drift and the storey shear force was found. At the top floor of the lighter building, the inter-storey drift and the storey shear force were increased in the range of 35–73% and 20–46%, respectively, compared with no-pounding events. In addition, severe damage at beam–column joints was found. Hence, lighter buildings require special attention during a seismic pounding event.
Publisher: Research Publishing Services
Date: 2011
Publisher: ISEC Press
Date: 11-2015
DOI: 10.14455/ISEC.RES.2015.72
Abstract: Alkali activated pozzolan are known low carbon cementitious binders which can be used to replace cement. The material is also known as geopolymer because of its three dimensional polymeric chain and ring like structure consisting silica and alumina. A common type of pozzolan used is fly ash because of its rich silica content therefore the term alkali activated fly-ash based binders is adopted. Despite much research and development of this material, there is no specific standard for design mix proportion. This research used the Taguchi’s design of experiment method to determine the optimum mix proportion of alkali activated fly ash based cement paste and mortar. Four factors were considered in the tests, silica fume, sand to cementitious ratio, liquid to solid ratio, and percentage of superplasticiser. Tests were conducted on the 9 batches of alkali activated fly-ash based paste and mortar s les to determine the compressive strength under ambient condition. Tests were also conducted to determine the residual strength of the s les after exposed to elevated temperatures. ANOVA analysis of the test results revealed the main factors contribution on the tested properties and led to the determination of the optimum design proportion of the factors considered in these tests.
Publisher: Elsevier BV
Date: 11-2020
Publisher: Elsevier BV
Date: 10-2014
Publisher: Elsevier BV
Date: 11-2007
Publisher: Springer Science and Business Media LLC
Date: 07-07-2020
DOI: 10.1038/S41598-020-67694-Z
Abstract: The transversely isotropic behaviour of thermal sprayed aluminium and zinc coating has been investigated based on a combination of nanoindentation experimental data and microporomechanics theory. A recently developed strength homogenisation approach comprises of the solid and porous medium is adopted to investigate the morphology properties of thermal sprayed aluminum and zinc coating. The finding of this paper demonstrates that the in idual aluminum and zinc phases in the coating have a characteristic packing density close to the theoretical highest spherical packing ratio for face-centred cubic and hexagonal close packed. Also, the plasticity properties of solid particles in both aluminum and zinc are found to have a significant transversely isotropic condition, while the elasticity properties are close to isotropic. These findings led to the conclusion that the anisotropic condition of the coating is dominantly affected by the plasticity properties, in terms of cohesion and friction coefficient.
Publisher: American Society of Civil Engineers (ASCE)
Date: 08-2021
Publisher: Research Publishing Services
Date: 2011
Publisher: Springer Science and Business Media LLC
Date: 12-09-2019
DOI: 10.1038/S41598-019-49780-Z
Abstract: Mechanical properties of materials can be derived from the force-displacement relationship through instrumented indentation tests. Complications arise when establishing the full elastic-plastic stress-strain relationship as the accuracy depends on how the material’s and indenter’s parameters are incorporated. For instance, the effect of the material work-hardening phenomenon such as the pile-up and sink-in effect cannot be accounted for with simplified analytical indentation solutions. Due to this limitation, this paper proposes a new inverse analysis approach based on dimensional functions analysis and artificial neural networks (ANNs). A database of the dimensional functions relating stress and strain parameters of materials has been developed. The database covers a wide range of engineering materials that have the yield strength-to-modulus ratio ( σ y /E) between 0.001 to 0.5, the work-hardening power ( n ) between 0–0.5, Poisson’s ratio ( v ) between 0.15–0.45, and the indentation angle ( θ ) between 65–80 degrees. The proposed algorithm enables determining the nanomechanical stress-strain parameters using the indentation force-displacement relationship, and is applicable to any materials that the properties are within the database range. The obtained results are validated with the conventional test results of steel and aluminum s les. To further demonstrate the application of the proposed algorithm, the nanomechanical stress-strain parameters of ordinary Portland cement phases were determined.
Publisher: MDPI AG
Date: 03-01-2019
DOI: 10.3390/MA12010130
Abstract: The carbonation rate of reinforced concrete is influenced by three parameters, namely temperature, relative humidity, and concentration of carbon dioxide (CO2) in the surroundings. As knowledge of the service lifespan of reinforced concrete is crucial in terms of corrosion, the carbonation process is important to study, and high-performance durable reinforced concretes can be produced to prolong the effects of corrosion. To examine carbonation resistance, accelerated carbonation testing was conducted in accordance with the standards of BS 1881-210:2013. In this study, 10–30% of micro palm oil fuel ash (mPOFA) and 0.5–1.5% of nano-POFA (nPOFA) were incorporated into concrete mixtures to determine the optimum amount for achieving the highest carbonation resistance after 28 days water curing and accelerated CO2 conditions up to 70 days of exposure. The effect of carbonation on concrete specimens with the inclusion of mPOFA and nPOFA was investigated. The carbonation depth was identified by phenolphthalein solution. The highest carbonation resistance of concrete was found after the inclusion of 10% mPOFA and 0.5% nPOFA, while the lowest carbonation resistance was found after the inclusion of 30% mPOFA and 1.5% nPOFA.
Publisher: Sri Lanka Journals Online (JOL)
Date: 31-03-2019
Publisher: American Society of Civil Engineers (ASCE)
Date: 05-2003
Publisher: Elsevier BV
Date: 02-2021
Publisher: Informa UK Limited
Date: 02-01-2016
Publisher: American Society of Civil Engineers (ASCE)
Date: 2003
Publisher: Elsevier BV
Date: 04-2018
Publisher: International Journal of Geomate
Date: 03-2018
Publisher: Elsevier BV
Date: 11-2018
Publisher: Wiley
Date: 30-10-2016
DOI: 10.1002/FAM.2276
Publisher: Research Publishing Services
Date: 2011
Publisher: Wiley
Date: 17-05-2018
DOI: 10.1002/FAM.2633
Publisher: Research Publishing Services
Date: 2011
Publisher: Elsevier BV
Date: 03-2016
Publisher: Informa UK Limited
Date: 30-10-2015
Publisher: Research Publishing Services
Date: 2012
Publisher: CRC Press
Date: 31-08-2012
DOI: 10.1201/B12754-13
Publisher: MDPI AG
Date: 24-12-2019
DOI: 10.3390/MA13010097
Abstract: The determination of elastic modulus (E) and hardness (H) relies on the accuracy of the contact area under the indenter tip, but this parameter cannot be explicitly measured during the nanoindentation process. This work presents a new approach that can derive the elastic modulus (E) and contact depth (hc) based on measured experiment stiffness using the continuous-stiffness-measurement (CSM) method. To achieve this, an inverse algorithm is proposed by incorporating a set of stiffness-based relationship functions that are derived from combining the dimensional analysis approach and computational simulation. This proposed solution considers both the sink-in and pile-up contact profiles therefore, it provides a more accurate solution when compared to a conventional method that only considers the sink-in contact profile. While the proposed solution is sensitive to Poisson’s ratio (ν) and the equivalent indentation conical angle (θ), it is not affected by material plasticity, including yield strength (σy) and work hardening (n) for the investigated range of 0.001 σy/E 0.5. The proposed stiffness-based approach can be used to consistently derive elastic modulus and hardness by using stiffness and the load-and-unload curve measured by the continuous-stiffness-measurement (CSM) method.
Publisher: Springer Science and Business Media LLC
Date: 25-02-2020
DOI: 10.1038/S41598-020-60152-W
Abstract: An estimation of the strength of composite materials with different strength behaviours of the matrix and inclusion is of great interest in science and engineering disciplines. Linear comparison composite (LCC) is an approach introduced for estimating the macroscopic strength of matrix-inclusion composites. The LCC approach has however not been expanded to model non-porous composites. Therefore, this paper is to fill this gap by developing a cohesive-strength method for modelling frictional composite materials, which can be porous and non-porous, using the LCC approach. The developed cohesive-strength homogenisation model represents the matrix and inclusion as a two-phase composite containing solids and pores. The model is then implemented in a multiscaling model in which porous cohesive-frictional solids intermix with each other at different scale levels classified as micro, meso and macro. The developed model satisfies an upscaling scheme and is suitable for investigating the effects of the microstructure, the composition, and the interface condition of the materials at micro scales on the macroscopic strength of the composites. To further demonstrate the application of the developed cohesive-strength homogenisation model, the cohesive-strength properties of very high strength concrete are determined using instrumented indentation, nonlinear limit analysis and second-order cone programming to obtain material properties at different scale levels.
Publisher: ISEC Press
Date: 11-2015
DOI: 10.14455/ISEC.RES.2015.108
Abstract: A newly developed four-node bilinear plate element based on linked interpolation and Desirable Displacement Field (DDF) concept is formulated for the analysis of general plate problems. The proposed element is formulated on a mixed finite element for Reissner-mindlin plate theory and transverse displacement is linked to the rotation degree of freedom to ensure high-order interpolation capacity. By assumed strain method, the DDF is introduced for the investigation of strain s ling points. A high order polynomial for transverse displacement with linking shape function is used in finite element discretization to provide a better solution for the plate problems. A number of commonly selected problems will be tested using the present element to compare with other element models in the open literature to assess their relative convergence and accuracy.
Publisher: American Society of Civil Engineers (ASCE)
Date: 06-1993
Publisher: Informa UK Limited
Date: 13-04-2022
Publisher: Informa UK Limited
Date: 2012
Publisher: Academic Journals
Date: 19-07-2012
DOI: 10.5897/SRE12.115
Publisher: American Society of Civil Engineers (ASCE)
Date: 06-2007
Publisher: Research Publishing Services
Date: 2013
Publisher: Research Publishing Services
Date: 2012
Publisher: Research Publishing Services
Date: 2011
Publisher: Elsevier BV
Date: 12-2012
Publisher: CRC Press
Date: 18-11-2010
DOI: 10.1201/B10571-43
Publisher: CRC Press
Date: 18-11-2010
DOI: 10.1201/B10571-44
Start Date: 2013
End Date: 2013
Funder: Curtin University of Technology
View Funded ActivityStart Date: 01-2018
End Date: 12-2023
Amount: $392,834.00
Funder: Australian Research Council
View Funded Activity