Properties of concrete containing coal bottom ash and fine coconut shell as partial sand replacement

The consumption of natural sand in concrete production is very high around the worldwide and it caused the shortage of natural fine aggregate which is suitable for construction in many countries [1]. This problem gives the chance for reuse by-products materials as a source of fine aggregate by partial or full replacement in construction activities. Hence, it can reduce the demand for extraction of natural raw materials and save landfill space other than reduce the consumption of natural resources [1]. Moreover, all over the world aimed at increasing the reuse and recycling suitable material for effective replacement of cement and fine aggregate in construction sector due to lack of natural resources.

Fine recycled concrete aggregate as a material replacement in concrete production

As a fast and rapid growing nation, Malaysia undergoes a lot of development especially in construction field. Most of the building nowadays are being made mainly using concrete as it provides many favorable features such as satisfactory compressive strength, durability, availability, versatility and cost effectiveness. However, in pursuing the development era, sometimes the authorities overlooked about the construction and demolition (C&D) waste that had been created along the development progress. Construction and demolition waste is becoming a vital issue especially to the environmental aspect in many large cities in the world (Chen et al., 2002). Shen [1] describe C&D waste as the waste which generated from renovation, site clearing, demolition, construction, roadwork, land excavation and civil and building construction. Construction and Demolition (C&D) waste constitutes a major portion of total solid waste production in the world, and most of it is used in landfills .

Performance of plastic wastes in fiber-reinforced concrete beams

Synthetic plastics are typically discarded, thus causing environmental pollution. Plastic wastes are recycled as fiber in concrete to solve this problem. In this study, synthetic fibers in a concrete matrix were investigated through compressive strength, splitting tensile, fracture energy, and flexural beam tests. The results show that an increase in fiber content improves the tensile strength of the concrete matrix. A high fiber content results in a substantial amount of fibers crossing a fractured section, thereby activating failure resistance mechanisms. Ring-shaped fibers, which are mainly designed to activate fiber yielding instead of fiber pullout, are better than irregularly shaped polyethylene terephthalate and waste wire fibers. Incorporating plastic fibers into concrete does not significantly change the failure mode of reinforced concrete beams compared to that of normal concrete beams. However, the first crack load presented improved results. The reinforced concrete containing ring-shaped plastic fibers with a width of 10 mm (RPET-10) exhibited remarkable results during the first crack load with an increment of 32.3%. It can be concluded that ring-shaped PET waste produces fiber concrete with a performance comparable to that of commercial synthetic fibers

Utilisation of Mussel Shell Ash and Palm Oil Leaves Ash as Admixture in Concrete

Mussel shell and palm oil leaves is a type of waste that generally undergo disposal process due to less-valuable materials. However, this waste are potentially to be used in concrete designing due to its cementing properties. Thus, this paper presenting the incorporation of mussel shell ash (MSA) and palm oil leaves ash (POLA) as an admixture in concrete.  MSA and POLA were obtained through grounding, burning and sieving process. As total, 84 concrete samples were mixed with different proportions of POLA (0.5%, 1% and 1.5%), MSA (1% and 2%) and K for control samples. All the samples were cured for 7 days and 28 days. The study was carried out to measure its physical and mechanical properties such as compressive, split tensile and capillary absorption analysis. While, its materials properties (MSA and POLA) were identified through its specific gravity test. The results demonstrated that B5 (1.5% POLA + 1% MSA) gave a good performance in concrete compressive strength on 7 and 28 days. Besides that, B5 also indicates a lower capillary water absorption compared to other specimens. Whereas B6 indicates a higher value for density analysis. Overall, the experimental result indicates that B5 does not giving any adverse effect on the concrete performance. Thus, it is prove that the utilisation of MSA and POLA as cementing materials are applicable in improving concrete strength and its durability accordingly to the selected percentages

Review of palm oil fuel ash and ceramic waste in the production of concrete

High demand for cement in the concrete production has been increased which become the problems in the industry. Thus, this problem will increase the production cost of construction material and the demand for affordable houses. Moreover, the production of Portland cement leads to the release of a significant amount of CO2 and other gases leading to the effect on global warming. The need for a sustainable and green construction building material is required in the construction industry. Hence, this paper presents utilization of palm oil fuel ash and ceramic waste as partial cement replacement in the production of concrete. Using both of this waste in the concrete production would benefit in many ways. It is able to save cost and energy other than protecting the environment. In short, 20% usage of palm oil fuel ash and 30% replacement of ceramic waste as cement replacement show the acceptable and satisfactory strength of concrete

Effect of Water to Cement Ratio and Replacement Percentage of Recycled Concrete Aggregate on the Concrete Strength

Fine Recycled Concrete Aggregate (FRCA) is one of the construction waste can be recycled. It can be the aggregate to replace the natural aggregate in concrete since we know the physical properties of materials are hard and strong. Demand for sand in the concrete production has been increased which become the problems in the concrete industry. This work deals with the effect of concrete incorporating with FRCA as partial replacement of sand. The percentage of natural sand replaced by the FRCA was 0%, 15%, 20%, 25%, 30%, 45% and 60%. Other than that, water cement ratio was manipulated variable started form 0.40, 0.45, 0.50, 0.55 and 0.60. In short, 20% replacement was the most suitable interaction of FRCA in the concrete occur that contribute to increasing in compressive strength. The porosity properties of FRCA been neutralized on that replacement percentage by the present of optimum filler effect generated form the very fine FRCA particle during the mixing process. Meanwhile, 0.50 water cement ratio was optimum condition for cement hydration process using FRCA as partial sand replacement

Significant factors of construction delays among contractors in Klang Valley and its mitigation

Construction industry has become one of the greatest income provider as it has contributed to the Gross Domestic Product (GDP) for Malaysia. However, construction sector has been much affected by unexpected situation such as construction delays. Delays in construction industry is one of the common problems that happened to most construction projects. By considering all viewpoint from various parties that involves in construction process such as contractors, client, consultant and others, this research identified the major factor that contributes to delays in Klang Valley, Malaysia. Questionnaires were distributed among respondents that involved in construction project in Klang Valley. The process of data analysis was conducted by using descriptive statistic that ranked the mean value of factors that contributes to delays. By using the ranking method, financial difficulties were recognized as the most significant factor that caused delays. Thus, by using the same method, some mitigation action has been proposed in order to avoid time overrun in construction

Significant Factors of Construction Delays Among Contractors in Klang Valley and its Mitigation

Construction industry has become one of the greatest income provider as it has contributed to the Gross Domestic Product (GDP) for Malaysia. However, construction sector has been much affected by unexpected situation such as construction delays. Delays in construction industry is one of the common problems that happened to most construction projects. By considering all viewpoint from various parties that involves in construction process such as contractors, client, consultant and others, this research identified the major factor that contributes to delays in Klang Valley, Malaysia. Questionnaires were distributed among respondents that involved in construction project in Klang Valley. The process of data analysis was conducted by using descriptive statistic that ranked the mean value of factors that contributes to delays. By using the ranking method, financial difficulties were recognized as the most significant factor that caused delays. Thus, by using the same method, some mitigation action has been proposed in order to avoid time overrun in constructio

Utilisation of mussel shell ash and palm oil leaves ash as admixture in concrete

Mussel shell and palm oil leaves is a type of waste that generally undergo disposal process due to less- valuable materials. However, this waste is potentially to be used in concrete designing due to its cementing properties. Thus, this paper presenting the incorporation of mussel shell ash (MSA) and palm oil leaves ash (POLA) as an admixture in concrete. MSA and POLA were obtained through grounding, burning and sieving process. As total, 84 concrete samples were mixed with different proportions of POLA (0.5%, 1% and 1.5%), MSA (1% and 2%) and K for control samples. All the samples were cured for 7 days and 28 days. The study was carried out to measure its physical and mechanical properties such as compressive, split tensile and capillary absorption analysis. While, its materials properties (MSA and POLA) were identified through its specific gravity test. The results demonstrated that B5 (1.5% POLA + 1% MSA) gave a good performance in concrete compressive strength on 7 and 28 days. Besides that, B5 also indicates a lower capillary water absorption compared to other specimens. Whereas B6 indicates a higher value for density analysis. Overall, the experimental result indicates that B5 does not giving any adverse effect on the concrete performance. Thus, it is proved that the utilisation of MSA and POLA as cementing materials are applicable in improving concrete strength and its durability accordingly to the selected percentage

Employability of local trained skill labour in construction industry

Development in Malaysia is booming which can be witnessed by the various construction projects that currently in progress, especially in the state of Johor which has the highest value of construction work completed for the third quarter of 2016. This necessarily requires skilled labours in a high number especially among the locals since it has been reported that Malaysia’s construction industry is having problems related to the shortage of local skilled labour. In addition, the local workers have been reported to unable to fulfil the demand of construction market and this have caused the contractor to import foreign workers to meet the needs and requirement of labour market in construction sector. The objectives of this study are to determine the criteria set by the construction company in recruiting local skilled labour and to study the strategies that can attract local skilled labour to join construction industry. Questionnaire has been distributed to G7 contractor in the state of Johor in order to achieve the objectives of this study. Collected data was then evaluated and tested for its reliability using the SPSS 20.0 software before it can be analysed in order to obtain the mean value, frequencies and percentage. The outcome of this study indicates that the prospective employer prefers to work with man and they require young, experienced, knowledgeable and skilled workers in doing the job. Most of the strategies that have been selected are mainly related to money namely salary increment, bonus, allowance and overtime payment, apart from upgrading labours welfare and providing a better accommodation. This study can be a guideline to both skills institution and contractor to improve on what they are lacking in order to encourage the local trained skills labour to join the industry