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This paper presents the investigation on built-up cold-formed steel column sections strengthened with carbon fibre-reinforced polymer (CFRP). Here, box-shaped column sections were fabricated by screwing together with individual channels. Behaviour of twelve plain and twelve CFRP-strengthened box sections was studied under axial compression. Three lengths of 300 mm, 500 mm and 700 mm with section thickness of 0.6 mm, 0.75 mm and 1 mm were studied in the investigation. The cold-formed steel design procedure suggested by North American specification AISI S100-16 and Euro code 3 (EC3) provisions was applied and compared with the experimental results, which were in good agreement. The results also indicate that the proposed strengthening technique is effective in repair and increasing the load-carrying capacity of cold-formed steel built-up box column.

This paper presents experimental findings of carbon fibre reinforced polymer (CFRP) strengthened cold-formed steel built-up channels subjected to axial load. In order to sensitively detect the buckling strengths and failure modes, twenty-four built-up columns were tested in which twelve columns were unadorned and another twelve columns were strengthened using CFRP sheets. The columns were tested for ultimate load, lateral displacement and failure modes. Tension coupon tests were conducted to determine the material properties of test specimens. The experimental results were compared with the design load calculated according to AISI S100-16 specification and are found to be in good agreement. It is established that the use of CFRP for strengthening increases the ultimate load and delays the buckling.

Environmental impact has become one of the major factors taken into consideration for recent civil engineering studies and projects. Thus, researchers have been concentrating on shear strengthening of existing reinforced concrete structure as an upgrade method instead of demolishing and reconstructing. In general, shear strengthening of RC beams using externally bonded steel plate has gained huge popularity. However, premature debonding of plates is the main drawback of the system, which could be mitigated using embedded connector; thus, the dimension of steel plate could be reduced significantly. Furthermore, numerical analysis on shear strengthening of beams using embedded connector would provide a great insight on the structural behavior. The aim of this research is to severely reduce the dimension of the steel plate using embedded connector for shear strengthening of RC beams and to investigate the performances of optimized shear-strengthened beams through experimental and numerical investigations. The results showed that the dimension of plate was reduced without debonding of the plate if the beam was designed for shear strengthening with the consideration of yield strength of steel plate and shear link. Experimental results showed a maximum increase in failure of 24%. The numerical results predicted accurately the structural performance of beams. The embedded connector had a great effect in deferring and minimizing the debonding failure and accordingly increasing the maximum load of shear failure between 14.5% and 24% compared to control beam.

Humanitarian logistics which is precisely known as humanitarian supply chain (HSC) plays a major role in reducing the impact of disaster on human life and livelihood by providing humanitarian aid in the forms of food, water, medicine, shelter and other supplies. Unfortunately, anecdotal evidences indicated that relief chain tends to be unstable, unpredictable and unresponsive to the needs of disaster victims. The 2004 Asian tsunami highlighted the lack of coordination between the relief chain linkages that hampered effective supply of aid. This phenomenon was further evident in our own context during the 2014 flood devastation in Peninsular Malaysia. Floodwaters and subsequent landslides blocked major roads, limiting access to evacuation centres and impeding the delivery of emergency relief supplies. Hence, an effective humanitarian supply chain management (HSCM) should be able to be deployed rapidly enabling provision of aid to beneficiaries. Notwithstanding the frequency and impact of disasters, humanitarian organizations today are under continuous pressure of improving their logistics performance. Departing from this need, this study aims to examine the criteria that influence the humanitarian aid actors in their decision making while increasing transparency and accountability of relief operations. Therefore, it is imperative for humanitarian sector to quantify the efficiency and effectiveness of a particular relief operation using set of performance metrics. A mixed methods approach comprising qualitative and quantitative survey will be used. The study intended to identify and define the metrics that would determine successful operational performance of disaster relief. This research will contribute mainly in the development of a HSCM performance model that (i) informs decision makers at the strategic, tactical and operational level in tracking progress, (ii) facilitate a more open and transparent communication and cooperation between humanitarian actors, and (iii) improve the logistics of disaster management both at the government and at non-governmental level.

Externally bonded method would be the most potential technique for optimal shear strengthening of deficient reinforced concrete (RC) beam subjected to eliminate premature debonding failure. The main aim of this research was to eliminate debonding failure of steel plate using embedded connector systems for optimal shear strengthening of RC beam. Dimensions of steel plates were optimized based on the proposed design guideline in accordance with EC2. The strengthened beams with connectors were then compared with those of U-jacketing system. Bond strength enhancements of steel plate using connectors were experimentally investigated through pullout test of prisms. The beam specimens were fabricated and tested to investigate the effects of embedded connectors. Result showed that steel bar and adhesive embedded connectors significantly increased the bond strength of externally bonded plates. The connectors completely prevented premature debonding failure of steel plates and allowed the beams to fail by flexure with full ductility and strength, whereas U-jacket showed the premature debonding of plates. The embedded connectors optimized/reduced the dimension of the externally bonded steel plate by 60% as compared to those of arbitrarily strengthened beam. The experimental results satisfactorily verified the proposed design guideline.

Objectives: Structural steel can be broadly classified into hot rolled steel and cold formed steel (CFS). CFS manufactured from roll forming or press braking operation. The main advantage of CFS sections are thin wall and light weight. These thin wall leads to buckling of structural member. This paper aims to study the capacity of Carbon Fibre Reinforced Polymer (CFRP) strengthened CFS channel beams, buckling behaviour, deflection and cost studies on CFRP strengthening. Methods/Statistical analysis: In this study three different length of CFS channel sections are selected for testing in which beams are tested for bending. All the beams were tested in plain section and CFRP strengthened series in universal testing machine. Findings: Experimental results shows the enhancement in capacity of beam due to CFRP strengthening. The local and distortional buckling modes were observed as failure modes. Experimental results were compared with maximum load resistance calculated by AISI specification which are in good agreement. Cost studies were compared on replacing a new member with CFRP strengthened channel member. Improvements/Applications: CFRP strengthening is suitable for enhancement of capacity of beams and repair. This CFRP strengthening technique can applied to reinforced concrete members, hot rolled steel, in filled steel tubes and bridges etc.

Shear strengthening of RC beam with adhesively bonded carbon fiber reinforced-polymer (CFRP) laminates is becoming both environmentally and economically more preferable than replacement. However, the early separation of these plated stripes was the most critical failure which leads to prevent reaching the full capacity required from the strengthening. This study aims to present a new method to prevent debonding failure of CFRP laminates adhesively glued to concrete surface using embedded connectors to enhance the interfacial bond strength. Therefore, steel bar and adhesive connectors were fabricated and used at the interface of the bonded CFRP laminates. Five beam specimens including one control beam were tested to investigate the effects of the connectors to prevent or delay the premature debonding of the EB CFRP laminates. The experimental results showed that both steel and adhesive connectors completely prevented premature debonding failure of CFRP shear strip and allowed the beams to fail by flexure with full ductility and strength. Steel and adhesive connectors would enhance 33% and 38% failure loads respectively as compared to strengthened beam without connectors.

Steel plates and carbon-fiber-reinforced polymer (CFRP) laminates or plates bonded to concrete substrates have been widely used for concrete strengthening. However, this technique cause plate debonding, which makes the strengthening system inefficient. The main objective of this study is to enhance the bond strength of externally bonded steel plates and CFRP laminates to the concrete surface by proposing new embedded adhesive and steel connectors. The effects of these new embedded connectors were investigated through the tests on 36 prism specimens. Parameters such as interfacial shear stress, fracture energy and the maximum strains in plates were also determined in this study and compared with the maximum value of debonding stresses using a relevant failure criterion by means of pullout test. The study indicates that the interfacial bond strength between the externally bonded plates and concrete can be increased remarkably by using these connectors. The investigation verifies that steel connectors increase the shear bond strength by 48% compared to 38% for the adhesive connectors. Thus, steel connectors are more effective than adhesive connectors in increasing shear bond strength. Results also show that the use of double connectors significantly increases interfacial shear stress and decrease debonding failure. Finally, a new proposed formula is modified to predict the maximum bond strength of steel plates and CFRP laminates adhesively glued to concrete in the presence of the embedded connectors.

The problem of debonding failure is a fundamental issue in concrete structures that are externally strengthened with adhesively glued plates. Many standards and studies recommend using single-lap pull-out tests to measure the ultimate force that causes debonding failure. The pull-out test also allows defining and calibrating interface bond-slip relationships between concrete and the bonded plates to obtain the maximum interfacial bond strength. The aim of this research was to enhance bond strength in the presence of embedded shear connectors, which were fabricated at concrete–adhesive interface level to delay debonding of the externally bonded strips from the concrete surface. A new rational model was also proposed to predict the bond strength of adhesively glued plates-to-concrete joints in the presence of connectors. In the experimental programme, 60 concrete prisms with adhesive and steel bar connectors were fabricated. The specimens were divided into two main series of concrete prisms bonded with steel plates and CFRP strips using the new connectors. Different diameters of connectors were used with and without adhesive on the surfaces of concrete prisms to bond the strips for investigating the capacity of the new embedded connectors. The experimental results showed that the interfacial bond strength increased remarkably when these connectors were used. Moreover, it was found that increasing the connector’s diameter has a great effect on increasing the bond strength and uniformly distributes the interfacial shear stresses, leading to the minimisation of premature debonding failure of bonded plates. The results exhibited that the steel connectors are more effective at increasing the shear bond strength for all specimens adhesively glued with both CFRP strips and steel plates. Finally, the proposed bond strength model was satisfactorily verified through the experimental investigations.

Repairing and strengthening of damaged reinforced concrete (RC) beams using externally bonded (EB) steel plates has gained universal acceptance. The disadvantage of this method, however, is the premature debonding of the externally bonded strip, which is brittle and an undesired mode of failure. It is also known that the debonding failure of EB steel plates prevents the RC beam from reaching its full strengthening capacity. This study aims to increase the scientific understanding of the behaviour of fully damaged RC beams strengthened/retrofitted in shear by means of EB steel plates. It also concentrates on preventing or delaying premature debonding of the adhesively bonded steel plates using new embedded adhesive and steel connectors. To achieve these objectives, seven beams with a deficient shear design were loaded monotonically up to maximum load capacities and repaired using the proposed connectors. One beam was used as a reference beam; the other six damaged beams were repaired with vertical and inclined steel plates. The presence/absence of the new embedded connectors was investigated with these two types of configurations. Theoretical models were also proposed to predict the effective debonding strain and the shear capacities of beam specimens. A comparison among these beams was done to investigate the efficiency of these connectors to enhance the bond strength between the externally bonded steel plates and the concrete surface on the web sides of the repaired RC beams. It is concluded that using steel and adhesive connectors to fix EB steel plates for repairing severely shear-damaged RC beams can delay the premature debonding failure and restore the original shear capacity of the these beams. Finally, the proposed model was satisfactorily verified through the experimental investigations and with the current design guidelines.

This paper presents the findings of investigation carried out on bricks made using fly ash and bottom ash using a non-conventional method. Bricks were cast using self-compacting mixtures of bottom ash, fly ash and cement eliminating both pressing and firing. Bricks were then tested for compressive strength, modulus of rupture, ultrasonic pulse velocity (UPV), water absorption, initial rate of suction, fire resistance and durability. The results showed better performance compared to conventional clay bricks in the properties investigated. Compressive strength was between 7.13 and 17.36 MPa, while UPV ranged from 2.2 to 2.96 km/s. Increase in fly ash reduced the water absorption. Tests for fire resistance indicated that the bricks did not show any spalling, and, there was increase in strength of up to 30% after heating. The optimum ratio of bottom ash, fly ash and cement was found to be 1:1:0.45 for better performance of bricks. It is concluded that bricks developed in this study can be used as an alternative to conventional bricks and hence can contribute to sustainable development.

In this research the effect of Coconut (CN) fibre on the fresh and thermo gravimetric properties of self-compacting concrete (SCC) at elevated temperatures was investigated experimentally and statistically. The mixtures containing cement, water, fly ash, fine aggregate, coarse aggregate and super plasticizer with the addition of CN fibres (0%, 0.05%, 0.10 %, and 0.15%) by volume of the mixtures were prepared. The fresh and thermo gravimetric properties of the SCC specimens were determined after mixing at elevated temperatures (200℃, 400℃, and 600℃) testing in a laboratory. Three control specimens with 0% CN fibres were used for every mixture of SCC. Regression models were developed to determine the responses. The optimum of the CN fibres was measured.

Cold formed steel differ from hot rolled steel by its lesser thickness and weight. The cold formed steel applicable in roof purlin, pipe racks and wall panels etc. Due its lesser wall thickness the cold formed steel member subjected to buckling. The enhancement of load carrying capacity of the cold formed steel member can be achieved by external strengthening of CFRP. In this study cold formed channel members connected back to back to form I shaped cross section using screws. These built up beam members were 300mm, 400mm and 500mm in length with 100mm screw spacing and edge distance of 50mm were chosen for testing. CFRP fabric cut according to length, width of built up beams and wrapped outer surface of beam using epoxy resin. Experiments were carried out in two sets firstly plain built up beams and secondly CFRP wrapped beams. The test results shows that increased load carrying capacity and reduction in deflection due to CFRP strengthening. Experimental results were compared with AISI standards which are in good agreement. Experimental results shows that CFRP strengthening is economic and reliable.

Shear cracking can have significant effects on interfacial bond strength of externally bonded (EB) plates, and thus development of a bond strength model considering effects of cracking is vital to predict debonding failure of shear strengthened reinforced concrete (RC) beams. The main aim of this study was to develop bond strength models of EB steel plate and CFRP laminate, considering effects of cracks, to predict debonding failures of shear strengthened RC beams. In the experimental program, forty-eight RC prisms were fabricated and strengthened using steel plate and CFRP laminate; all prisms in this category were tested using a special indirect pull out test to incorporate cracks. To validate the models, four full-scale RC beams were shear strengthened using EB steel plate and CFRP laminate. Based on the results of cracked prisms, interfacial bond strength models of EB steel plate and CFRP laminate have been developed. The proposed models showed that the presence of cracks reduced the interfacial bond strengths of EB steel plate and CFRP laminate significantly, and the bond strength was also reduced because of increased length and width of EB steel plate and CFRP laminate. As compared to existing models, the proposed models showed lower interfacial bond strength of EB plates. The predicted debonding failure loads of steel plate and CFRP laminate shear strengthened RC beams using the proposed models were 3.4% and 4.7% differences when compared to experimental results, respectively. However, the models from existing research had shown significantly higher debonding failure loads as compared to those of experimental results.

Repair of reinforced concrete beam with externally bonded steel plate or fibre reinforced polymer (FRP) laminate is becoming both environmentally and economically preferable rather than replacement of deficient beam. The well known advantages of external reinforcement over other methods include; low cost, ease of maintenance and the ability to strengthen part of the structure while it is still in use. The disadvantage of this method, however, is the premature debonding of the externally bonded strips which is brittle and undesired mode of failure. It is also known that debonding of the externally bonded steel plates prevents the reinforced concrete (RC) beam from reaching its full strengthening capacity. The aim of this study was to increase the scientific understanding on the behaviour of damaged reinforced concrete beams strengthened and/or retrofitted for shear using vertical steel plate fixed with adhesive and steel connectors to eliminate or delay debonding failure. Four reinforced concrete beam specimens were prepared to investigate the effects of connectors in preventing or delaying premature debonding of shear strips to restore the capacities of fully damaged beams. Three damaged beams have been repaired and strengthened with steel plates and loaded monotonically up to the maximum load capacities in order to define load–deflection relationship. It is concluded that the repairing of severely shear-damaged RC beams with steel plates by using steel and adhesive connectors can fully restore the original shear capacities of the beams.

During the recent decades, Carbon Fiber-Reinforced Polymer (CFRP) composite materials have proven valuable properties and suitability to be used in the construction of new buildings and in upgrading the existing ones. The objective of this paper is to review the previous work in this area and compare it with the current experimental results to show the design equations for CFRP strengthened steel structural elements. Research findings have shown that CFRP sheets and strips are not only effective in restoring the lost capacity of a damaged steel section, but are also quite effective in strengthening of steel sections to resist higher loads, extend their fatigue life and reduce crack propagation.

Cold-formed steel members usually display local-global buckling interaction which strongly effects the structural strength of columns. Through strengthening web of the members this buckling can be controlled to some extent. In this investigation, Carbon Fibre Reinforced Polymers (CFRP) is used for strengthening cold formed steel channel member. This paper presents compression tests of cold-formed plain and CFRP strengthened steel channel section columns. This paper also proposes a design method based on Direct Strength Method provisions specified in American Iron and Steel Institute (AISI), for determining the axial compression strength. Results obtained from the proposed design method are compared with experimental test data and are found to be in good agreement.

Carbon fiber reinforced polymer (CFRP) composites are considered to have high performance and potential for use in strengthening , retrofitting and for the rehabilitation of structural sections. In this paper, design procedures are proposed for the axial load capacity of cold formed steel lipped channel columns strengthened with carbon fiber reinforced polymer (CFRP). For the purpose of validation, the results are based on the proposed design equation from the North American specification for the design of cold-formed steel structural members (AISI-2007) and Euro code for cold-formed members and sheeting (EC3-EN1993-1-3:2006) are compared against the experimental test data. The test results showed that the capacity of the columns are close to the theoretical values predicted by the AISI-2007 and EC 3 provisions. Some tested specimens showed reduced capacity and premature failure due to peeling and debonding of the CFRP from the steel. Various experimental investigations are suggested for future work to further validate and update the design equations. From the experimental studies, it has been observed that there is significant increase in strength due to CFRP strengthening.

This paper presents the findings on an investigation done on the use of Quarry dust, Fly ash and Billet scale in developing bricks. Bricks were made with various proportions of those materials and cement. Tests for fresh density, compressive strength, and water absorption were conducted. The compressive strength of bricks ranged from (7.2-26.3) MPa, the water absorption fell in range between (13-14.26) %. The optimum ratio of Fly ash and Billet scale is 1:1. It is shown that bricks with enhanced properties can be developed using these industrial wastes.

The objective of this study is to determine if adjustment of the four factors viz. cement content (C), water to powder (w/p) ratio, fly ash (FA) content, and superplasticizer (SP) will increase the compressive strength of self-compacting concrete (SCC) by using contrast constant factorial design and response surface methodology. The method of the analyzing 2k factorial design that is a design with k factors each at two levels was used with 16 factorial points. It is concluded that the interactions of the parameters of a couple effect of C with SP, w/p with SP, FA with SP, and C with FA and SP in a full quadratic model are the only significant effects and the underlying assumptions of the analysis are satisfied. In maximizing compressive strength, variables such as cement content A or x1, water to powder ratio B or x2, fly ash content C or x3, and super plasticizer dosage D or x4 should be at a high level of significance and the process is relatively robust (exhibiting strength) to superplasticizer D.

This paper reports the findings of an investigation done on bricks made using fly ash (FA), quarry dust (QD), and billet scale (BS) by non conventional method. The procedure for producing the bricks includes mixing the constituents along with cement and water, and then forming the bricks within moulds without applying pressure over them. Unlike the traditional method of brick manufacturing, the new approach neither uses clay or shale nor requires high pressure on mould or high temperature kiln firing having remarkable environmental and ecological gain. Results for mechanical properties and durability were rewarding and promising. The optimum ratio of billet scale and fly ash is found to be 1:1, billet scale and quarry dust is 1:1. It is indicated that the bricks developed in this study can be used as an alternative to conventional bricks.

This research aims to identify Malaysia construction industry’s procurement system as well as its supplier selection decision making factors. This study also aims to establish a metric importance hierarchy as well as to find the correlation of metrics with major stakeholders of the construction industry. All this is done through a mixed-method approach using survey questionnaire and semi-structured interviews. Target respondents are from Public Works Department headquarters in Malaysia that are directly involved with supplier selection. Findings shows that an established construct of metric hierarchy simplifies supplier selection process as well as the process can be made optimal with less errors. This will anticipate more path of improvement towards the current policies besides creating a more transparent procurement process in supplier selection. Moreover, developing a systematic procedure in supplier selection will enable and ensure better optimization in construction projects. Hence, this will boost organizational effectiveness and profit and further improve the procurement development in Malaysia. The final outcome of this study is to embark in greater supplier selection standards and to raise procurement to the next level.

Supplier selection of electricity power generating, transmitting and distributing system is part of problem solving environment in a power utility as it is a long-term investment for the organization. Therefore, the supplier selection decision making directly influences the operational and financial positions of a power utility. In addition, the supplier selection of a power-related system is a complex multi-criteria decision problem. While some criteria may be common across different industries, there is no denying the fact that some criteria are likely to be unique to the power industry. This research aims to understand what constitutes the suitable supplier selection criteria in a power utility. This study reveals some interesting findings in regard to how engineers perceive the importance of each criterion and strongly suggest that product quality, price and delivery are key determination in the supplier evaluation process. Eighteen criteria considered for this study were mapped onto their respective cluster, namely: supplier�s organizational system and technology, buyer-supplier relationship and economic value. The findings of this study should assist various groups of stakeholder (e.g. suppliers, buyers and end-users) to gain a better understanding of social behaviour in making decisions of purchase, particularly with regard to power utilities.

This research presents the details of an investigation carried out to study the effect of the addition of constituent material parameters on the fresh and hardened state properties of self-compacting concrete using a central composite design approach combined with response surface methodology. Self-Compacting Concrete (SCC) mixtures were made with the addition cement, coarse aggregate, sand, fly ash and super plasticizer in various proportions and their fresh state properties (J-ring, segregation resistance and V-funnel) and hardened properties (compressive strength at 28 days and modulus of elasticity) were measured. Results were analysed using a statistical model that was able to predict the effect of the independent variables on the responses by using multiple regression analysis. The coupled effect of the responses was carried out. An analysis of variance was used to determine the adequacy between the model and experimental values. It was concluded that models of a full quadratic can be used to evaluate the influence of constituent materials on the properties of SCC. All the mixtures developed exhibited fresh state property values which were within the range permitted in the SCC guidelines. Optimizations of the responses were done by using response surface methodology. It was concluded that the fresh properties cited were 18.3 seconds V-funnel, 849 mm J-ring flow, and 17.8% segregation resistance and the hardened properties were 35.254 to 48.174 MPa of the compressive strength and 27.214 to 39.026 MPa for the modulus of elasticity.

In this study, the effect of polypropylene (PP) fibers on thermogravimetric parameters of self-compacting concrete (SCC) containing indigenous materials was investigated experimentally and statistically. The mixes containing cement, water, fly ash, fine aggregate, coarse aggregate, and super plasticizer, with the addition of PP fibers (0%, 0.05%, 0.1%, and 0.15%) by volume of the mixtures, were prepared. The physical properties of SCC were determined at elevated temperatures (200, 400, and 600 °C) after cooling in the laboratory. Regression models were developed to determine the responses, and the optimum amount of 0.05% PP fibers by volume was measured. Copyright © 2012 John Wiley & Sons, Ltd.

One of the most highlighted issues in the developing world of the 21st century is the hydrometeorological disasters. Developed and developing nations are all affected by the more prominent climate change. There has been a rise in disaster occurrences over the past decade that this has caused more attention to be given to the topic of disaster management especially to floods. The scale of these disaster events has also intensified and have broken past records with more destructive disasters. This paper intends to review the activities related to hydrometeorological disaster. Key activities are broken down into three different phases, namely pre-disaster, during disaster and post-disaster. Understanding the activities involved is pertinent to not only the lead agencies and non-governmental organizations but plays a bigger role for the vulnerable communities. In the past, communities were the last group to be participative in disaster risk reduction efforts. Today, communities are being engaged from early stage to empower them to be resilient towards the possibility of facing future flood disaster. Evacuation planning and logistics arrangement are key activities prior to the occurrence of any disaster which will ease the implementation of search and rescue operations. However during disaster, it is important for the early warning system to be functioning to alert the affected communities. People also need to be aware of the outbreak of diseases during flood disaster. Finally, post-disaster efforts focuses more on the restoration of damaged infrastructure as well as the mental state of the affected victims. Understanding these key activities will increase the awareness of stakeholders in reducing loss of life and minimizing damages towards properties.

This paper presents the results of a research project aimed at providing standard circular web openings to the popular precast pretensioned inverted T-beam. Opening size and placement and required materials strengths were investigated. In this paper the nonlinear analysis and design of simply supported pretensioned inverted T-beam with circular web openings are presented. Two design parameters are varied: opening location and number of openings. The results from nonlinear finite element analysis were substantiated by test results from five pretensioned inverted T-beams with web opening and one solid beam. Good agreement is shown between the theoretical and the experimental results. The test results obtained from this investigation show that the performance of the specimens with web openings is almost identical to that of the specimen without web openings. A simple design method for pretensioned inverted T-beam with circular web openings is proposed.

Problem statement: For predicting workability and hardened properties of Self-Compacting Concrete (SCC) no well known explicit formulation. Approach: Statistical models were carried out to model the influence of key mixture parameter (cement, water to powder ratio, fly ash and super plasticizer) on hardened properties affecting the performance of SCC. Such responses included compressive strength at 3, 7 and 28 days and modulus of elasticity. Thirty one mixtures were prepared to derive the numerical models and evaluate the accuracy. The models were valid for a wide range of mixture proportioning. Results: The research presented derived numerical models that can be useful to reduce the test procedures and trials needed for the proportioning of self-compacting concrete. The qualities of these models were evaluated based on several factors such as level prediction, residual error, residual mean square and correlation coefficients. Conclusion: Full quadratic models in all the response (compressive strength at 3,7 and 28 days and modulus of elasticity) showed high correlation coefficient (R2), adjusted correlation coefficient, less level of significant and sum of square errors from the four predictions models (linear, interaction, full quadratic and pure quadratic) were developed.

This paper presents the results of a research project aimed at providing standard circular web openings to the popular precast pretensioned inverted T-beam. The main advantage of these openings is that mechanical equipment can pass through the webs of inverted T-beams. Another advantage is a slight reduction in inverted T-beams weight that would improve the demand on the supporting frame both under gravity loading and seismic excitation. Opening size and placement and required materials strengths were investigated. Also, the effects of using straight tendons, rather than two-point depression and one-point depression, of the prestressing strands were investigated. In this paper the nonlinear analysis and design of simply supported pre-tensioned inverted T-beam with circular web openings are presented. Two design parameters are varied such as: opening location and numbers of openings. The results from a nonlinear finite element analysis are substantiated by test results from five pretensioned inverted T-beam with web opening and one solid beam. Good agreement is shown between the theoretical and the experimental results. The effect of openings on the behavior of such beams at different stages of loading is presented. The test results obtained from this investigation show that the performance of the specimens with web openings was almost identical to that of the specimen without web openings. A simple design method for estimating the cracking load for the different crack patterns is proposed. Based on these tests, design recommendations are made that will allow the addition of web openings to inverted T-beam with minimal additional calculation.

A precast, prestressed concrete girder with circular web openings allows building service systems (mechanical, electrical, communications, and plumbing) to cross the girder line within the member’s depth, reducing a building’s floor-to-floor height and the overall height of the structure. These height reductions have the potential to improve the competitiveness of total precast concrete structures versus other types of building systems. The experimental program reported in this paper tested five full-scale inverted-tee girders with circular web openings to failure, to evaluate the openings’ effect on girder behavior. The girders failed in a ductile manner due to diagonal cracking above the openings. The tested girders were designed using available recommendations in the existing literatures. It was observed that concrete fractured from tension zones around an opening, with cracks developing vetically towards the beam flanges. A beam would collapse when the cracks reached the flanges. In the present work, an analytical solution is developed for the load-deflection calculation of prestressed beam with web openings at any load stage. The solution assumes a trilinear deflection response characterized by the flexural cracking initiation, steel yielding, and ultimate capacity. Closed form expressions are presented for the case of simple beams subjected to four-points loading. These expressions are modified from present ACI code equations by incorporating appropriate laboratory determined coefficients in order to predict more precisely with some degree of conservativeness on flexural load-point deflection with any extent of uncracked, postcracked, and postyielded region along their spans. Accordingly, a simplified analysis procedure is developed by adopting a trilinear load-deflection response. The effectiveness of the simplified procedure is demonstrated by comparing its results to those of the analytical solution and the experimental values.

For the past few years, natural disaster has been the subject of debate in disaster management especially in flood disaster. Each year, natural disaster results in significant loss of life, destruction of homes and public infrastructure, and economic hardship. Hence, an effective and efficient flood disaster management would assure non-futile efforts for life saving. The aim of this article is to examine the relationship between approach, decision maker, influence factor, result, and ethic to decision making for flood disaster management in Malaysia. The key elements of decision making in the disaster management were studied based on the literature. Questionnaire surveys were administered among lead agencies at East Coast of Malaysia in the state of Kelantan and Pahang. A total of 307 valid responses had been obtained for further analysis. Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA) were carried out to analyse the measurement model involved in the study. The CFA for second-order reflective and first-order reflective measurement model indicates that approach, decision maker, influence factor, result, and ethic have a significant and direct effect on decision making during disaster. The results from this study showed that decision- making during disaster is an important element for disaster management to necessitate a successful collaborative decision making. The measurement model is accepted to proceed with further analysis known as Structural Equation Modeling (SEM) and can be assessed for the future research.

This paper investigate the performance of banana fibre reinforced slabs 300mm × 300mm size with varied thickness subjected to low impact projectile test. A self-fabricated drop-weight impact test rig with a steel ball weight of 1.25 kg drop at 1 m height has been used in this research work. The main variables for the study is to find the relationship of the impact resistance against the BF contents and slab thickness. A linear relationship has been established between first and ultimate crack resistance against BF contents and slab thickness by the experiment. The linear relationship has also been established between the service (first) crack and ultimate crack resistance against the BF contents for a constant spacing for various banana fibre reinforced slab thickness. The increment in BF content has more effect on the first crack resistance than the ultimate crack resistance. The linear relationship has also been established between the service (first) crack and ultimate crack resistance against the various slab thickness. Overall 1.5% BF content with slab thickness of 40 mm exhibit better first and ultimate crack resistance up to 16 times and up to 17 times respectively against control slab (without BF)

This paper investigate the performance of lightweight rice husk concrete (LWRHC) with varied bamboo reinforcement content for the concrete slab of 300mm × 300mm size reinforced with varied slab thickness subjected to low impact projectile test. A self-fabricated drop-weight impact test rig with a steel ball weight of 1.236 kg drop at 0.65 m height has been used in this research work. The main variables for the study is to find the relationship of the impact resistance against the amount of bamboo reinforcement and slab thickness. A linear relationship has been established between first and ultimate crack resistance against bamboo diameters and slab thickness by the experiment. The linear relationship has also been established between the service (first) crack and ultimate crack resistance against the bamboo reinforcement diameter and slab thickness. 5% RH content exhibit better first and ultimate crack resistance up to 1.80 times and up to 1.72 times respectively against 10% RH content.

This paper intends to fathom the current state of procurement system in Malaysia specifically in the construction industry in the aspect of supplier selection. This paper propose a comprehensive study on the supplier selection metrics for infrastructure building, weight the importance of each metrics assigned and to find the relationship between the metrics among initiators, decision makers, buyers and users. With the metrics hierarchy of criteria importance, a supplier selection process can be defined, repeated and audited with lesser complications or difficulties. This will help the field of procurement to improve as this research is able to develop and redefine policies and procedures that have been set in supplier selection. Developing this systematic process will enable optimization of supplier selection and thus increasing the value for every stakeholders as the process of selection is greatly simplified. With a new redefined policy and procedure, it does not only increase the company's effectiveness and profit, but also make it available for the company to reach greater heights in the advancement of procurement in Malaysia.

This paper investigate the effect of the thickness and mesh spacing on the impact of ferrocement for the concrete slab of 300mm × 300mm size reinforced subjected to low impact projectile test. A self-fabricated drop-weight impact test rig with a steel ball weight of 1.236 kg drop at height of 150 mm, 350mm, and 500mm has been used in this research work. The objective of this research is to study the relationship of impact resistance of ferrocement against the mortar grade and slab thickness. There is a good linear correlation between impact resistance of ferrocement against the mortar grade and the thickness of ferrocement slab. The first and ultimate crack impact resistance of mortar grade 43 (for 40 mm thick slab with mesh reinforcement) are 1.60 times and 1.53 times respectively against the mortar grade 17 slab (of same thickness with mesh reinforcement). The first and ultimate crack impact resistance for 40 mm thick slab (mortar grade 43 with mesh reinforcement) are 3.55 times and 4.49 times respectively against the 20 mm thick slab (of same mortar grade with mesh reinforcement).

This paper investigate the effect of the thickness and fibre volume fraction (VF) on the impact performance of steel fibre reinforced concrete (SFRC) for the concrete slab of 300mm × 300mm size reinforced subjected to low impact projectile test. A self-fabricated drop-weight impact test rig with a steel ball weight of 1.236 kg drop at 0.57 m height has been used in this research work. The objective of this research is to study the relationship of impact resistance SFRC against slab thickness and volume fraction. There is a good linear correlation between impact resistances of SFRC against slab thickness. However the impact resistance of SFRC against percentage of volume fraction exhibit a non-linear relationship.

This paper investigate the effect of the mesh distribution on the impact performance of steel fibre reinforced concrete (SFRC) for the concrete slab of 300mm × 300mm size reinforced with varied thickness and fraction volume subjected to low impact projectile test. A self-fabricated drop-weight impact test rig with a steel ball weight of 1.236 kg drop at 0.57 m height has been used in this research work. The objective of this research is to study the effect of the mesh distribution on the impact resistance SFRC for various slab thickness and fraction volume. Random fibre distribution is the more effective than the top and bottom fibre distribution in terms of absorption of impact energy, crack resistance, the ability to control crack formation and propagation against impact energy.

Flooding is the utmost major natural hazard in Malaysia in terms of populations affected, frequency, area extent, flood duration and social economic damage. The recent flood devastation towards the end of 2014 witnessed almost 250,000 people being displaced from eight states in Peninsular Malaysia. The affected victims required evacuation within a short period of time to the designated evacuation centres. An effective and efficient flood disaster management would assure non-futile efforts for life-saving. Effective flood disaster management requires collective and cooperative emergency teamwork from various government agencies. Intergovernmental collaborations among government agencies at different levels have become part of flood disaster management due to the need for sharing resources and coordinating efforts. Collaborative decision making during disaster is an integral element in providing prompt and effective response for evacuating the victims.

This paper investigates the effect of the thickness and mesh spacing on the impact of ferrocement for the concrete slab of 300mm x 300mm size reinforced subjected to low impact projectile test. A self-fabricated drop-weight impact test rig with a steel ball weight of 1.236 kg drop at height of 150 mm, 350mm, and 500mm has been used in this research work. The objective of this research is to study the relationship of impact resistance of ferrocement against slab thickness and mesh reinforcement spacing. There is a good linear correlation between impact resistance of ferrocement against slab thickness and its mesh spacing. The first and ultimate crack impact resistance for 40 mm slab are 2.00 times and 1.84 times respectively against the 20 mm slab with the same mesh spacing. The first and ultimate crack impact resistance for 40 mm slab with 20 mm mesh spacing are 2.24 times and 3.70 times respectively against 50 mm mesh spacing with the same slab thickness. The mesh with higher content of reinforcement provides more contribution to the slab resistance as compare with the thickness.

This paper investigate the effect of the mesh distribution on the impact performance of kenaf fibre mesh reinforced concrete (KFMRC) for the concrete slab of 300mm × 300mm size reinforced with varied thickness and mesh diameter subjected to low impact projectile test. A self-fabricated drop-weight impact test rig with a steel ball weight of 1.236 kg drop at 0.40 m height has been used in this research work. The objective of this research is to study the effect of the mesh distribution on the impact resistance kenaf fibre mesh concrete for various slab thickness and mesh diameter. 2-layers one Top and one Bottom mesh distribution kenaf mesh is the most efficient in the ability to control crack formation and propagation against impact energy followed by 1-layer Middle mesh distribution and lastly the 1-layer Top mesh distribution is the least effective.

This paper investigate the performance of kenaf fibre mesh reinforced concrete (KFMRC) with varied kenaf fibre mesh reinforcement content for the concrete slab of 300mm × 300mm size reinforced with different mesh diameter at constant spacing with varied slab thickness subjected to low impact projectile test. A self-fabricated drop-weight impact test rig with a steel ball weight of 1.236 kg drop at 0.40 m height has been used in this research work. The main variables for the study is to find the relationship of the impact resistance against the amount of mesh reinforcement and slab thickness. A linear relationship has been established between first and ultimate crack resistance against kenaf fiber diameters by the experiment. The linear relationship has also been established between the service (first) crack and ultimate crack resistance against the slab thickness. The threshold (highest) values for service crack and ultimate crack is 47.9 N/mm2 and 130.58 N/mm2 respectively observed and computed for 50 mm slab with 7 mm diameter mesh.

This paper proposes a conceptual framework to compare criteria/factor that influence the supplier selection. A mixed methods approach comprising qualitative and quantitative survey will be used. The study intend to identify and define the metrics that key stakeholders at Public Works Department (PWD) believed should be used for supplier. The outcomes would foresee the possible initiatives to bring procurement in PWD to a strategic level. The results will provide a deeper understanding of drivers for supplier's selection in the construction industry. The obtained output will benefit many parties involved in the supplier selection decision-making. The findings provides useful information and greater understanding of the perceptions that PWD executives hold regarding supplier selection and the extent to which these perceptions are consistent with findings from prior studies. The findings from this paper can be utilized as input for policy makers to outline any changes in the current procurement code of practice in order to enhance the degree of transparency and integrity in decision-making.