Papers by Keyword: Construction Waste

Abstract: This study aims to develop and validate a comprehensive strategy consisting of four dimensions for effectively managing construction waste (CW) arising during the Architectural Design Process (ADP) within Architectural Design Firms (ADFs) in Egypt. To accomplish this aim, a hybrid research approach, integrating qualitative and quantitative methods, was designed to address four specific objectives. Firstly, a thorough literature review was conducted to explore the topics of ADP, CW, Waste Management (WM), as well as national and international Waste Management Strategies (WMS). Secondly, three construction-based case studies from Saudi Arabia, China, and Thailand were gathered and analyzed to investigate the efficacy of identified WMS in managing CW originating during ADP. Thirdly, a survey questionnaire was administered to a representative sample of ADFs in Egypt to assess their understanding and utilization of WMS during ADP. Finally, the research formulated and validated a four-dimensional strategy for managing CW originating during ADP in ADFs. Data analysis revealed that ADFs possess a moderate level of knowledge regarding WMS, with limited awareness of Egyptian laws, regulations, and WMS during ADP. Among the identified WMS, "Prefabrication" emerged as the most favoured, followed by Building Information Modeling (BIM) and "on-site waste management". However, the implementation of these strategies faces several challenges. Furthermore, the research identified "preparation and briefing" as the design stage most susceptible to CW causes, with "waiting" and "defects" being the most prevalent forms of CW originating during ADP.

Abstract: Expansive soils are known to show significant volumetric changes in response to changes in the moisture content. Such soils swell when the moisture content is increased and shrink when the moisture content is decreased, thereby causing distress and damages to structures founded on them. Construction developments on naturally occurring expansive soils are usually problematic. This study examines the properties of expansive soil obtained from the city of Muscat in Oman. The expansive soil samples were further treated with gypsum, which was obtained from waste plasterboards, at varying quantities of 3%, 6%, 9% and 12% by mass in an attempt to stabilize the soil. Based on USCS classification system, the expansive soil was identified a poorly clay with high plasticity (CH) with AASHTO classification of A-6. The pH test confirms the reaction between expansive and gypsum, while both the compaction and unconfined compression strength (UCS) tests revealed the optimum percentage of gypsum required to enhance the properties of expansive soil to be 9% by mass. The unconfined compression strength (UCS) test yielded a 37.7% increase over that of untreated expansive soil at 28 days of curing. The California Bearing Ratio (CBR) test of the treated soil yielded a 57% increase in CBR value for expansive soil treated with 9% of waste gypsum over untreated expansive at the unsoaked state and 70% at soaked state. Overall, a solid understanding of the physical and engineering properties of expansive soil, and the confirmation of the potential use of gypsum for its stabilization, was achieved in this study.

Abstract: Roof tile waste is one of the wastes which usually generated during construction and demolition activity. It is then disposed at landfill and causes environmental pollution. Rising concrete production pushes for larger quantity of sand to be harvested from river. Excessive sand mining harms the environment and affect the water quality. The approach of using roof tile waste as fine aggregate replacement in concrete would lead to a cleaner environment and more sustainable river ecosystem. This study investigates the influence of crushed roof tile waste on the workability, compressive strength, and water absorption of concrete. A total of five concrete mixes containing various proportion of crushed roof tile waste as partial fine aggregate replacement were prepared. The percentage of crushed roof tile waste used as partial fine aggregate replacement is 0, 5, 10, 15 and 20 by weight of sand. The concrete mixes were subjected to slump test, compressive strength test and water absorption test. The workability of concrete reduced when a larger amount of waste roof tiles was substituted as fine aggregate. The use of 40% roof tile waste as partial fine aggregate replacement increases the concrete strength. Concrete mix that contains roof tile waste exhibits lower water absorption than control concrete specimens and it can be classified as good quality concrete. Conclusively, the integration of roof tile waste would reduce burden at landfill and also lower down the dependency of concrete industry on river sand supply.

Abstract: Construction and demolition waste (CDW) is very high in quantity, 30% - 40% of total solid waste and their management is inadequate and lack the integration of sustainability concepts. This situation leads to severe environmental effects, which are mainly associated with the production of new building materials due to the low recovery rate. In fact some studies show that 5-10% of total energy consumption across the EU is related to the manufacture of construction products. For this reason, CDW is a priority for many policies globally. For several years, a growing trend towards more sustainable construction processes has been taking place with a focus on secondary raw materials with lower environmental impacts on the entire life cycle. For this reason, this paper intends to contribute to increasing knowledge in this field through a review article. The review has the aim to evaluate the research gap, strategies to reduce construction waste and to promote the recycled materials use for a circular economy in construction sector. The results of the study showed that interest in this field of research has grown strongly over the years: the most publications on the subject relate to the last five years. On the other hand, issues relating to the topic did not attract particular interest in the range 2010-2016, in fact the number of publications in this period did not exceed 4%. The research showed that Europe is among the communities most sensitive to the issue and it has clearly revealed that there are still many barriers and research gaps to be overcome on this issue and the study has tried to identify the main ones.

Abstract: Construction waste is a serious challenge that requires particular attention from construction managers to improve the performance of their projects and survive in a highly competitive market. Simulation modeling provides decision-makers with a controllable operating system and a more cost-effective environment which allows a better understanding of construction processes deficiencies. The current paper aims to assess waste in a bricklaying process using ARENA. Data used for simulation modelling were collected through field observations and video recording techniques. Using EasyFit, goodness-of-fit tests were performed to identify the best probabilistic density functions for each construction operation in the studied process. Simulation outputs show that non-value-added (NVA) activities dominate the bricklaying process with 85.2 % of the total cycle time. These results indicate a strong potential for optimizing the process under study by reducing these sources of waste especially regarding waiting time that holds the highest share of waste with 72.5 %.

Abstract: The present study investigates waste generation during the production and erection phase of a prefabricated single family house in Austria as a basis for identifying waste prevention potentials. Therefore, the material composition of a case study building (wood frame construction) is compared to waste generated during production and erection. In order to assess the whole life cycle of prefabricated buildings the use phase as well as the end-of-life phase are also considered. Examples are given to show how different measures can impact the generation of waste directly and indirectly. The results show that production and erection are already very efficient with regard to waste generation and prevention potentials mainly exist in further offcut reduction and optimization in packaging. The use phase and the end-of-life of the building are more complex to investigate and waste prevention potentials are less tangible. However, important measures for waste reduction are related to the easy exchangeability of building components as well as their reusability. The lifetime extension of the building and building components, which can be achieved through proper operation and maintenance, can be considered a key issue for preventing waste in the building sector.

Abstract: The main aim of this contribution is comparison the properties of fine aggregate concrete with partial replacement of sand by fine recycled aggregate. The fine recycled aggregate originated from two different sources. The main topic of this article is the study of influence of the origin of FRA to fine aggregate concrete properties. The compressive strength, flexural strength and freeze-thaw resistance were tested. The mechanical properties and weight were examined after 28 and 60 days and after 25, 50, 75 and 100 cycles of freeze-thaw. Partial replacement of sand was 25 and 50 % for all these tests. The properties were investigated by using prismatic specimens.

Abstract: Due to the increasing concern about the environment and depleting conventional materials, a lot of research is going on in the field of material science to develop environment friendly materials, and to improve the recycling and reusing of waste materials. Composites are material providing possibilities to reach these targets. In this experimental study, the possibilities and potential in the utilization of mixed waste from recycling in the manufacturing of epoxy composites are studied. The studied properties are flexural properties, i.e. flexural strength and flexural modulus, and hardness as mechanical properties, and water absorption and thickness swelling as physical properties. Element analysis was used to determine the composition of construction and demolition waste used in manufacturing. The analysis revealed a large proportion of mineral elements with high hardness. Consequently, this had a clear impact on the hardness of the composite. The flexural properties were found to be on a reasonable level. The waste-epoxy composite showed a low uptake of water due to the minor content of hydrophilic materials present in the composite.

Abstract: Construction industry is one of the most important sectors for the Malaysian economic growth where it remains as the fastest growing activity for several years. The issue of rapid country development which has positive influence of generating high construction waste is very commonly related to this industry. One of the major contributors of construction waste is steel. Steel is expensive and can contribute to overall project cost implication. Hence, the amount of steel waste needsto be quantifiedat the initial stage. Thus,steel waste quantification model is an important element to be considered for better waste management. By using the data collected in the Central region in Malaysia, an empirical model, Estimation Model of Steel Waste Material has been developed to estimate the amount of steel waste generation based on certain variables. This study aims to investigate and verify the effectiveness of the model by using the data collected from the Northern region in Malaysia. The value of the Mean Absolute Percentage Error (MAPE), 23.02% indicates that the model performance is common and acceptable. Thus, the model has good potential to be adopted by the industry practitioners to plan a better and more effective waste management.

Abstract: The main aim of this contribution is verification of durability properties of concrete with partial replacement of cement by recycled cement powder (RCP) sourced from pure waste concrete. The main topic of this article is the study of influence of partial replacement of cement by RCP to the carbonation resistance of fine aggregate concrete with partial replacement of cement. The compressive strength, tensile strength in bending and depth of carbonation were tested after 56 days of CO² curing. Partial replacement of cement was 0, 5, 10 and 15 % for all these tests. The properties were investigated by using prismatic specimens.