Decision-Making Method Employed at Construction Planning Phase of Housing Development

A correct decision made by decision-makers, at the planning phase, determines the success of a housing development project. Detailed decision supporting data is needed to provide specific guidance to private housing developers. The purpose of this paper is to define a decision-making method to be employed at the construction planning phase of a housing development project in Malaysia. Survey method is implemented using a questionnaire that was distributed to 67 private housing developers. The collected data was then analysed via Statistical Package for Social Sciences (SPSS) software. The outcomes of the analysis show that for Malaysian private housing developers, discussion and market/economic report are the most important methods that are applied while making a decision for a housing development project. Thus, this paper is supposed to guide private housing developers as well as governments in making decisions at the construction planning phase of housing development projects in Malaysia

Impact of cover/bar diameter ratio to the structural performance of reinforced concrete member due to corrosion

Corrosion of steel in reinforced concrete is one of the main issues among construction stakeholders. The main consequences of steel corrosion include loss of cross section of steel area, generation of expansive pressure which caused cracking of concrete, spalling and delaminating of the concrete cover. Thus, it reduces the bond strength between the steel reinforcing bar and concrete, and deteriorating the strength of the structure. The objective of this study is to investigate the impact of c/d ratio to the structural performance of reinforced concrete member due to corrosion. A series of reinforced concrete cylinder of ϕ100mm x 200mm, ϕ150mm x 300mm and ϕ200mm x 400mm with c/d ratio of 2.13, 3.45 and 4.76 was modelled consisting of 19mm diameter of reinforcement bar at the center of the cylinder. Corrosion rate of 0%, 5% and 10% of rebar corrosion is used in parametric study to assess the influence of different level of corrosion rate to the structural performance. As a result, a positive linear relationship was sketched between the increase of expansive pressure and the corrosion rate for each c/d ratio. Meanwhile, the expansive pressure is inversely proportional to the c/d ratio due to the deflection effect in the larger concrete cover is smaller compared to the lower c/d ratio which is more severe. Furthermore, the analysis shows that there is a significant effect on the failure pressure for each c/d ratio as the failure pressure of lower c/d ratio increase proportionally with the increase of c/d ratio. This study could predict the structural deterioration by numerical analysis using the c/d ratio. Hence, the findings provide a good input in designing a structure which takes into account the c/d ratio and also the corrosion level of the structure

An Analysis of Chemical-Mechanical Damage in Reinforced Concrete Beams

Nowadays, a major issue in the field of construction is the deterioration of reinforced concrete structures due to chemical and mechanical attacks. This deterioration directly impacts construction safety and serviceability, as well as the cost of maintenance. For the purpose of maintaining safety and serviceability, it is necessary to evaluate the durability of existing structures accurately, in order to predict the structure's deterioration and its future strength. In this study, an experiment was conducted in which the electrolytic process was carried out for several levels of corrosion. Next, a static loading test was adopted to assess the structural performance and obtain the ultimate strength of the beam. In addition, continuum damage mechanics were utilized in the analysis of damage caused by chemical and mechanical effects. Within the framework of this method, chemical damage caused by the corrosion of steel bars was considered. Then the coupling effects of chemical and mechanical damage were calculated by introducing two independent scalar damage variables into the constitutive equation. To calculate the chemical damage evolution, we carried out a diffusion process of chloride ions that impact the corrosion of steel bars in concrete, and an evaluation was conducted on an affected cross-sectional area of a steel bar. The proposed method was found to validate the experiment's results and could predict the ultimate strength under various exposure conditions. Moreover, the proposed orthotropic conditions may be carried out as an alternative to isotropic analysis in order to identify the worst-case scenario of the structure

Reinforced concrete by using the rectangular shape of voided beam

In conventional RC beam, the transition from compression to tension zone of the beam when load applied producing ineffective region at the middle area of the neutral axis. This is because, the area experiencing less compression and tension compare to the region above and below the neutral axis. Thus, the purpose of this research is to replace the use of concrete at the middle of the neutral axis by incorporating 4 PVC pipes to reduce cost and the self-weight of the structure. 4 pipes with a diameter of 20mm, 25mm and 50mm will be combined together to form a continuous voided square beam of V40, V50 and V100. The size of RC beam specimens is 1200mm x 160mm x 160mm, these beams were test with 3-point load test to identify the flexural strength. From the test, the ordinary beam recorded lowest maximum load, which is 15,35kN and VRB 100mm is the strongest beam with the maximum load 33.75kN and has the highest strength increment compared to another voided rectangular beam. Besides that, VRB 100mm also can reduced until 42.69% self-weight of RC beam and reduce until 37.5% of the concrete usage. From this study, it shows that the Voided Square Beam can reduce the self-weight of beam and reduce the concrete usage. Besides that, this idea also can implement to produce the lightweight structure that meet the standard of Industrialized Building System (IBS)

Influential Factors for Effective Materials Management in Construction Projects

Construction projects are plagued with the issue of poor project performance such as low productivity, wastage, time overrun, compromised quality and cost overrun. Research literature reveals that this issue occurs partly due to ineffective materials management. Nonetheless, the effective management of materials seems like a viable solution to enhance the performance of any construction projects. Despite its importance, not much literature has explored the influential factors for effective management of materials. Since the identification of factors is an essential step to recommend any improvement efforts, thus, this paper examines the influential factors for effective materials management. A questionnaire survey was conducted with practitioners from contractor organisations and 111 valid responses were obtained. Data was analysed using exploratory factor analysis via the IBM SPSS version 21 software. Results indicate that only 50 influential factors were relevant in Malaysian construction project and these were categorised into 8 specific components namely: management, purchasing, expediting, transportation, site storage and condition, supplier, contractual and governmental interference. Summarily, findings reported in this paper constitute part of a questionnaire development process for a research project undertaken to develop an effective materials management model for better projects performance. Thus, the outcome of this study may assist practitioners in decision making process by understanding the identified influential factors that contribute to effective materials management

The Performance of Bamboo Fiber as Fine Aggregate Replacement in Concrete

The rapid growth of construction industry has caused a huge demand on natural aggregate as the production of concrete requires massive use of natural stone materials. Due to the increase of demand of this material, it has affected to the shortage of natural aggregate and increased the cost of construction material. On the other hand, bamboo is one of the materials which have a big population and potential to be used in construction due to its durability, flexibility and strength performance. So, bamboo fiber was used as aggregate replacement material to reduce the cost of construction material and pollution as well as to improve the quality of the concrete. The research objectives in this study are to determine the optimum percentage of bamboo fiber as aggregate replacement in concrete and to compare the compressive strength of the bamboo fiber concrete with standard concrete. There were 4 cube specimens casted for each proportion of 0%, 5%, 12.5%, 10%, 12.5%, 15% and 17.5% of bamboo fiber as aggregate replacement in concrete. Then, the compressive strength test was conducted to find the optimum bamboo fiber contents with the maximum workability and strength of the concrete. The findings showed that the replacement of 5% of bamboo fiber achieved the highest strength with 27.77 N/mm2 and the strength decrement difference is only about 2.38% with standard concrete. Based from the result, the 5% bamboo fiber concrete can be suggested as the optimum percentage of bamboo fiber as aggregate replacement in concrete. This study is not only aim in reducing the cost of construction material but it also can be one of the effectives ways to reduce environmental impact by using natural fibers as aggregates replacement

Potential Implementation of Light Steel Panel System For Affordable Housing Project In Malaysia

The high demand-supply gap of affordable housing has been a major issue in Malaysia and has increased housing prices. A conventional method of construction is not reliable in delivering the increased demand for housing. Additionally, Industrialised Building System (IBS) faced difficulties to be implemented smoothly due to the issue related time, cost and quality. Therefore, light steel panel (LSP) system, is one of the IBS types; can be utilized in a housing construction project. This new system can replace the conventional method that was currently used in the construction of an affordable housing project. The objectives of this study are to identify the potential of LSP and the influencing factors of system implementation. Interviews are conducted with three project managers who have working experience in Syarikat Perumahan Negara Berhad (SPNB), Kumpulan Prasarana Rakyat Johor Sdn Bhd (KPRJ) and PIJ Property Development Sdn Bhd as a developer of affordable housing in Johor. Two contractors from G1 which have more than three years’ experiences in implementing affordable housing project in Malaysia were also interviewed. Based on the interview, it is expected to define the potential and influencing factors of the LSP system. The findings are meaningful in framing and enhancing construction housing method of an affordable housing project in Malaysia

The Performance of Bamboo Fiber as Fine Aggregate Replacement in Concrete

The rapid growth of construction industry has caused a huge demand on natural aggregate as the production of concrete requires massive use of natural stone materials. Due to the increase of demand of this material, it has affected to the shortage of natural aggregate and increased the cost of construction material. On the other hand, bamboo is one of the materials which have a big population and potential to be used in construction due to its durability, flexibility and strength performance. So, bamboo fiber was used as aggregate replacement material to reduce the cost of construction material and pollution as well as to improve the quality of the concrete. The research objectives in this study are to determine the optimum percentage of bamboo fiber as aggregate replacement in concrete and to compare the compressive strength of the bamboo fiber concrete with standard concrete. There were 4 cube specimens casted for each proportion of 0%, 5%, 12.5%, 10%, 12.5%, 15% and 17.5% of bamboo fiber as aggregate replacement in concrete. Then, the compressive strength test was conducted to find the optimum bamboo fiber contents with the maximum workability and strength of the concrete. The findings showed that the replacement of 5% of bamboo fiber achieved the highest strength with 27.77 N/mm2 and the strength decrement difference is only about 2.38% with standard concrete. Based from the result, the 5% bamboo fiber concrete can be suggested as the optimum percentage of bamboo fiber as aggregate replacement in concrete. This study is not only aim in reducing the cost of construction material but it also can be one of the effectives ways to reduce environmental impact by using natural fibers as aggregates replacement

E-SPAH: Aesthetic Innovation in UTHM's Small-scale Rainwater Harvesting System

A rainwater harvesting (RWH) system is a method of storing rainwater for future purposes. Universiti Tun Hussein Onn Malaysia (UTHM) has implemented this effort on some of the buildings in Main Campus, Parit Raja. However, this system has the weakness that caused the RWH system to stop from appropriately operated. Some of the RWH components are damaged because the design is not thought of thoroughly in the long term. Furthermore, the Main Campus is highly dependent on the treated water supply that caused a high amount of utility bills. Therefore, this study has highlighted the need to analyse the existing small scale RWH system in UTHM's Main Campus, identify the suitable tank form for UTHM's Main Campus small scale RWH system, and suggest a small scale RWH system's design for outdoor purposes in Main Campus UTHM. This study has been carried out by using literature review, interview session and observation. The result shows that the small scale RWH system in UTHM Main Campus has a few strengths, weaknesses, opportunities, and threats. Cylindrical tank form is chosen to design the university's small scale RWH system. A modular RWH system with the number of tanks installed based on rainwater catchment area is suggested and named E-SPAH, a concept of RWH system that emphasises efficiency and outdoor usage. Perhaps this study would help future researchers, universities, and contractors guide future small-scale rainwater harvesting systems for outdoor purposes in UTHM's Main Campus

Improving Contractors' Practices of Industrialized Building System (IBS) Implementation in Construction Industry

Abstract: Nowadays, the Malaysian construction industry is moving forward to roll out technology advantage across project life-cycle for enhancing human development skills. Therefore, the government has adopted industrialized building systems (IBS) to enhance control and balance of workforce supply for overall project performance achievement. However, the challenges faced by the construction industry such as delay the completion of construction projects was due to poor contractors' practices. In addition, there are significant challenges related to contractors' practices for instance shortage of skill, practical know-how, worker capability, and financial difficulties in IBS implementation. Therefore the purpose of this study was to identify current practices and influencing factors of contractors' practices for IBS implementation in the construction industry. This study also determines the improved ways of contractors' practices for IBS implementation in the construction industry. The study was conducted in Johor Bahru, Johor where various development and construction activities are currently active. Quantitative method was conducted by distribution the questionnaires to Grade 7 (G7) contractors as study respondents which involved wide practices of IBS construction projects. Data collected were analysed using the Statistical Package for the Social Science (SPSS) 22.0 software. The study reveals that, the problems faced by contractors in their practices of IBS implementation such as low productivity, management aspects, and financial problems. Therefore, training to labour, IBS instruction guideline and improving finance, and procurement mechanism are the top recommended factors to improve contractors' practices for successful IBS implementation. In conclusion, with the improvement of contractors' practices, the productivity of IBS implementation in the construction industry can be improved