Production Of Construction Waste Research Articles

The Cost of Urban Renewal: Annual Construction Waste Estimation via Multi-Scale Target Information Extraction and Attention-Enhanced Networks in Changping District, Beijing

Construction waste is an inevitable byproduct of urban renewal, causing severe pressure on the environment, health, and ecology. Accurately estimating the production of construction waste is crucial for assessing the consumption of urban renewal. However, traditional manual estimation methods rely heavily on statistical data and historical experience, which lack flexibility in practical applications and are time-consuming and labor-intensive. In addition, their accuracy and timeliness need to be improved urgently. Fortunately, with the advantages of high-resolution remote sensing images (HRSIs) such as strong timeliness, large amounts of information, and macroscopic observations, they are suitable for the large-scale dynamic change detection of construction waste. However, the existing deep learning models have a relatively poor ability to extract and fuse features for small and multi-scale targets, and it is difficult to deal with irregularly shaped and fragmented detection areas. Therefore, this study proposes a Multi-scale Target Attention-Enhanced Network (MT-AENet), which is used to dynamically track and detect changes in buildings and construction waste disposal sites through HRSIs and accurately estimate the annual production of urban construction waste. The MT-AENet introduces a novel encoder–decoder architecture. In the encoder, ResNet-101 is utilized to extract high-level semantic features. A depthwise separable-atrous spatial pyramid pooling (DS-ASPP) module with different dilation rates is constructed to address insufficient receptive fields, resolving the issue of discontinuous holes when extracting large targets. A dual-attention mechanism module (DAMM) is employed to better preserve positional and channel details. In the decoder, multi-scale feature fusion (MS-FF) is utilized to capture contextual information, integrating shallow and intermediate features of the backbone network, thereby enhancing extraction capabilities in complex scenes. The MT-AENet is used to extract buildings and construction waste at different periods in the study area, and the actual production and landfill volume of construction waste are calculated based on area changes, indirectly measuring the rate of urban construction waste resource conversion. The experimental results in Changping District, Beijing demonstrate that the MT-AENet outperforms existing baseline networks in extracting buildings and construction waste. The results of this study are validated according to government statistical standards, providing a promising direction for efficiently analyzing the consumption of urban renewal.

Mechanical Properties of Pervious Recycled Aggregate Concrete Reinforced with Sackcloth Fibers (SF)

The excessive production of construction waste is a significant concern as it requires proper disposal and may become economically unfeasible. Reusing construction waste in producing new concrete can substantially reduce the disposal requirements of construction waste. In addition, this results in a sustainable solution for the rapidly depleting natural resources of concrete. Pervious concrete may contain up to 80% coarse aggregates and could be an exceptional host for reusing construction waste. This study aimed to investigate the mechanical properties of pervious concrete constructed with natural and recycled aggregates. The substandard properties of recycled aggregates were improved by adding natural fibers from sackcloth. This study presents an experimental program on 45 samples of pervious concrete with air void ratios and the size of coarse aggregates as the parameters of interest. The compressive strength of the pervious concrete decreased by increasing the air void ratio regardless of the size of the aggregates. The type of aggregates did not influence the permeability of pervious concrete, and the maximum temperature in pervious concrete increased as the quantity of air void ratios increased. The decrease in compressive strength was 40–60% as the void ratio was increased from 10–30% for all types of concrete mixes, such as natural and recycled aggregates. The permeability of small-size aggregates with 10% designed air void ratios for natural and recycled aggregates with sackcloth was 0.705 cm/s.

Seismic Vulnerability Analysis of Masonry Structures Built with Disassembled Brick Wall Sections

Disassembling brick wall pieces into brick wall sections and constructing masonry buildings with disassembled brick wall sections (DBWSs) can reduce construction waste production at source and help achieve carbon peak and carbon neutrality. A finite element model (FEM) for typical MSBD is established based on the calibrated finite element analysis method to evaluate the seismic performance of masonry structures built with disassembled brick wall sections (MSBD). Subsequently, the peak ground acceleration is selected as the ground motion intensity index, and the maximum inter-story displacement angle is chosen as the structural damage index. The 20 ground motion records are selected and scaled by peak acceleration in 0.2 g steps to form 120 structure-ground vibration samples for incremental dynamic analysis (IDA) and seismic vulnerability analysis. The IDA results indicated that with the gradual increase in peak ground acceleration, the maximum inter-story displacement angle increases and the model transits from the elastic stage to the elastoplastic stage. Because the characteristics of ground motion records are different, the order of structural plasticity development will be different and the number of ground motion records needs to be considered in the seismic performance assessment. The calculation model will not collapse under the 7 and 8 degree design-based earthquake and the probability of moderate and severe damage of the structure under the rare earthquake is minimal, according to the seismic vulnerability curves. The seismic vulnerability analysis results indicate that MSBD has good seismic performance under earthquakes and meets the requirements of “perfect subjected to frequent earthquake, reparable subjected to design based earthquake, no collapse subjected to rare earthquake.” The seismic vulnerability analysis based on probability statistics can provide a reference for seismic design and evaluation of earthquake damage.

From waste to resource management? Construction and demolition waste management through the lens of institutional work

The European Union has issued action plans to reduce the production of construction waste and increase the reuse and recycling of materials in the hope of triggering a rapid transition towards a Circular Economy (CE). The management of construction and demolition waste, however, struggles to apply these measures. Our purpose, therefore, is to analyse how different actors involved in the management of waste could contribute to transform existing practices so that they respond to the shifting demands of legislation and support CE. To understand how this transformation work is performed, we build on the concept of institutional work, which enables us to describe how actors, rather than accepting institutions as permanent and immovable, contribute to their development by creating, maintaining or disrupting the existing institution. Drawing on qualitative research methods, we collected empirical data through 31 semi-structured interviews, observations of meetings and site visits. Our results show that whereas the production of waste is somewhat reduced, and the sorting of fractions improved, the institutional work performed is not sufficient to translate sustainability into new economic values. Although the work performed legitimizes CE principles and enables new initiatives, it mostly fails to change normative associations and to define new rules of action that support CE.

Effect of pores on the mechanical and durability properties on high strength recycled fine aggregate mortar

Larger consumption of natural fine aggregates (NFA) leads to an increase in cost, energy, and negative environmental impact. On the contrary, the larger production of construction waste results in the generation of recycled fine aggregate (RFA), which requires safe disposal. The aim of study, is to the hunt for such alternatives, compares the mortar mechanical and durability properties with and without RFA. High strength mortar specimens were produced with mix proportion as 1:3 using RFA as partial replacement for NFA as 0%, 25%, 50% and 100%. The mechanical and durability performance of all specimens was assessed in the terms of compressive strength, flexural strength, water absorption and mercury intrusion porosimetry. Mechanical performance is confirmed by microscopic studies. The main results display that the mortar with 25% of RFA, performed better, which are related to pore structures and their distribution. It is noted that the, pores also increase with the increase in RFA content. The effect of pores on the strength and their relationships are assessed.

Challenges Towards Reducing Illegal Dumping Activities in the Construction Industry

This nowadays an increasing number of construction projects in Malaysia have contributed to the production of construction waste which has had a negative impact on the environment, especially through illegal dumping. The increasing number of illegal dumping activities is a sign that construction waste management needs to be examined. To date, a comprehensive criterion for construction waste management, in developing countries is still not clearly defined. Therefore, the objectives of this paper are to investigate current illegal dumping activities, and identify the challenges towards reducing illegal dumping activities in the Malaysian construction industry. Hence, this research conducted interviews with 20 expert stakeholders related to construction waste management in order to scrutinise illegal dumping activities in Malaysia. The data from these semi-structured interviews were analysed by content analysis. The findings are used to determine the current challenges for reducing illegal dumping activities in the Malaysian construction industry. The elements in the current findings are potentially to improve construction waste management in order to archive the proper construction waste management. Finally, this findings will help to identify strategies to reduce illegal dumping activities and to enhance challenges towards reducing illegal dumping activities in the Malaysian construction industry.

Construction Waste Production in Macroeconomic Context

This article aims at presenting the economic impacts of implementing the basic principles of construction demolition waste management in terms of saving construction costs. Emphasis is placed on fulfilling the 3R principle, i.e. reducing waste, reusing it, and recycling resources and products. Construction and demolition waste represents the largest mass waste flow in the EU, e.g. in 2018, it represented 36% of the total waste production in the whole EU- 27. The European Union is gradually introducing measures to reduce the production of construction waste compared to the Czech Republic, where the share of construction demolition waste on the total production was up to 42% in 2018. This value exceeds the EU-27 average. The article analyses available statistical data from the national CZSO and the European statistical office EUROSTAT on the waste production classified according to EWC-STAT, which is a classification of waste according to Directive No. 2150/2002. Items monitoring the waste produced by the construction industry are listed on the 41st to 43rd place of the EWC-STAT list of all monitored waste. The data obtained allows comparing three branches of construction production, the 41st Building construction, 42nd Civil engineering, and 43rd Specialized construction activities. Another possibility to obtain data is to use a division according to the waste producer economic activity (CZ NACE). The data obtained in this way is compared with the performance indicators of the national economy. By comparing the size of the construction demolition waste production with the performance of the national economy (especially the GDP indicator), the degree of their interdependence was determined. The aim of the analysis is to assess the relation between the country’s economic performance and the production of construction and demolition waste. The next step was to perform an analysis from the point of view of the 3R principle in order to examine the impact of measures to reduce the construction demolition waste production in connection with the already initiated processes of its possible recycling or reuse.

Study on Estimation Method of New Construction Waste

With the rapid development of construction industry and the large discharge of construction waste, there are many environmental problems. In order to formulate and implement the strategy of reducing management at the project level, it is necessary to estimate the amount of construction waste production accurately. Based on two methods, the building area method and the BIM method are used to estimate the amount of construction waste generated by a new residence, and a comparative model is established. According to the results, the method based on BIM can accurately estimate the amount of residential construction waste, improve the management level of residential construction waste and reduce environmental pollution.

An LCA-based model for assessing prevention versus non-prevention of construction waste in buildings

Waste generated by the Construction Sector represents an environmental problem in many countries. To achieve increasingly eco-efficient waste management, Life Cycle Assessment (LCA) provides an objective method for the quantification of the potential impact that waste management exerts on the environment. Traditionally, LCA has focused on the evaluation of non-prevention scenarios once the waste is generated, mainly by showing the benefits of recycling vs. disposal. Consequently, the literature has hardly addressed the positive environmental impacts caused by waste prevention, that is, the reduction at source, which constitutes the preferred option of any waste management hierarchy. Therefore, this study proposes a model to simulate the environmental performance of the prevention vs. the non-prevention of construction waste production. The model is applied to an urban system of residential buildings in Spain. The results provide evidence of the environmental benefits achieved with the prevention scenario. The prevention scenario reduces the construction waste generated in the non-prevention scenarios by up to 57%. Furthermore, it allows a potential reduction of up to 4.6 and 171.1 times the impact caused by the disposal scenario; and up to 1.7 and 8.3 times those of the recycling scenario. The model can be implemented in other contexts with other reference buildings, and enables the environmental benefits of reduction strategies to be studied, thereby providing a tool to guide and support decision-making during the building design stage. Moreover, the results obtained can help professionals and policymakers to incorporate effective construction waste prevention measures in waste prevention plans and programs.

Studies on combined effects of graphene oxide-fly ash hybrid on the workability, mechanical performance and pore structures of cementitious grouting under high W/C ratio

The superior workability and high early strength of cementitious composites make them have become the most consumed grouting materials in fundamental construction and engineering. However, using cement as grouting materials also brings many issues, such as energy consumption, CO2 emissions, and construction waste production, etc. Here, we real that the industrial by-products fly ash combining with graphene oxide (GO) can be used as a substitute for binder materials to reduce the amount of cement in grouting pastes. The results suggest that fly ash can further improve the workability of grouting materials by reducing the friction effect between the cement particles, and GO can be used to compensate for the loss of mechanical properties caused by fly ash replacing part of the cement powders. 20 wt% fly ash combined with 0.08 wt% GO is proven to be used to effectively replace cement powders of equal weight without influencing the mechanical properties of grouting materials. Microstructure characterization further suggests that GO would not only act as refined templates for the reaction products to grow in cementitious pastes, but also generates as addition nucleation sites into the pore space of fresh binder and promotes more hydration products to grow. The findings of this study promote a great chance to fabricate high performance, lower price, and more environmentally friendly grouting materials in the future.

Математичне моделювання прогнозування обсягів продукування будівельних відходів в різних країнах світу

Construction waste can be widely used in construction: as a filler and binder for the production of concrete, dry mixtures and other building materials, for the production of building materials with protective properties, etc. Tstudy of the volume of construction waste in different countries around the world by planning a second-order experiment by the Box-Wilson method using rotatable central compositional planning using the developed software, which is protected by a certificate of the work. The aim of the study is to determine by planning a regression model to predict the production of construction waste in different countries from the main parameters of influence. The regression dependence of forecasting the volume of construction waste production in different countries of the world on the main parameters of influence: population density, gross domestic product per capita, human development index, average latitude of the country. It is established that according to Fisher's criterion the hypothesis about the adequacy of the obtained regression model can be considered correct with 95 % reliability. The correlation coefficient was 0,99475, which indicates sufficient reliability of the obtained results. The obtained regression dependence can be used when developing a strategy for construction waste management. It was established that among the factors of influence that were considered, the volume of gross domestic product per capita has the greatest impact on the volume of construction waste production, and the index of human development has the least. The response surfaces of the target function are constructed - the volumes of construction waste production in different countries of the world and their two-dimensional cross-sections in the planes of impact parameters.

Prediction of construction waste in representative cities of North and South based on Grey Model

With the orderly promotion of construction waste treatment in China, the process of construction waste reduction is also gradually launched. At present, the production of construction waste in many cities is in the historical high decline stage. In order to better plan the capacity of urban construction waste treatment and recycling, it is necessary to forecast the output of construction waste in a period of time in the future. Based on the historical data from 2012 to 2018 in the statistical yearbook, this paper forecasts the construction waste production from 2020 to 2023 in Shenyang Dalian, the core city of Northeast China, and Guangzhou and Shenzhen, the provincial capitals of Guangdong Province. By comparing the growth trend of population with the growth trend of construction waste, it is found that the growth of construction waste is along with the increase trend of population. Meanwhile, four suggestions for urban waste disposal are provided.

Discussion on Classification System of Construction Waste in China

With the continuous recommendation of the urbanization process in China, the production of construction waste is also increasing. At present, the utilization of construction waste resources in China is relatively low, mostly landfilling disposal. The environmental problems caused by landfill disposal are becoming more and more serious, but also a great waste of resources. Fine classification of construction waste source is the premise and key to promote the precise management and control of construction waste. This paper makes a thorough investigation and literature analysis on the classification methods of construction waste in developed countries abroad and the Post-disposal modes brought by classification. Based on the current situation and existing problems of classification of construction waste in China, six first-level classification and 28 second-level classification are proposed. The results of construction waste and the feasibility of the results are discussed and analyzed in order to provide reference for the classification of buildings in China.

Research on Rapid Detection Technology and Application of Mortar Compressive Strength Based on Neural Network

Since the rapid development of the construction industry, the production of construction waste has also multiplied, and the construction waste has caused tremendous pressure on the environment. Therefore, the main research of this subject is that the waste concrete is formed into a recycled material after a certain treatment--concrete powder. And the cement in the dry-mixed mortar is replaced by 0-30% concrete powder. The compressive strength of recycled concrete powder under different dosages was tested by experimental method. The compressive strength is then applied to the artificial neural network to establish a predictive model. Taking time as a variable, the feasibility and the best dosage of the 28-day compressive strength method for the 3d compressive strength during the test are discussed. In order to reduce the test cycle, improve work efficiency, and ultimately achieve the purpose of improving construction waste utilization.

Man-made Disaster Prevention using Waste Management Hierarchy and Disaster Management Cycle

The amount of construction waste generated is enormous due to the growth of the construction activities, which might lead to serious environmental problems. This is also including the construction waste that was generated from the natural disaster. This potential human-made disaster has been receiving worldwide attention and becomes a significant concern across nations. Thus, many studies on the effectiveness of construction waste management practices have been done. However, statistics do not show any improvement in the number of construction waste production. This paper aims to investigate the state of the art of construction waste management practice in Malaysia and the human-made disaster management strategies that feasible to be applied. Data were collected using the semi-structured interview with the key informants of the construction professional service providers in Malaysia and analyzed through thematic content analysis. An in-depth conceptualization and a new theoretical insight are developed on the strategy to prevent this human-made disaster caused by the construction waste. Findings from the cross-sectional content analysis and cognitive mapping propose a new human-made disaster management strategy in the construction caused by the construction waste that suits to Malaysian context.

Improvement of construction waste resource treatment process

With the continuous increase of construction waste production in China, the treatment of construction waste resources is an important way to reduce. In this paper, the problems existing in the traditional process are improved and optimized. The improved process flow is optimized from four aspects: increasing the crushing ratio, improving the screening effect, enhancing the aggregate strength and reducing the dust. The focus is on the particle shaping and strengthening process, gel strengthening process and crushing spray dust removal process of the crushed aggregate, which makes up for the shortcomings of the current treatment process and improves the treatment efficiency and quality of construction waste. The focus is on the particle shaping and strengthening process, gel strengthening process and crushing spray dust removal process of the crushed aggregate, which makes up for the shortcomings of the current treatment process and improves the treatment efficiency and quality of construction waste. It can provide reference for the treatment of construction waste resources.

Compressive Strength and Infiltration Characteristic of Pervious Concrete Using Recycled Concrete Aggregate

In construction industry, rapid development will increase the demand versus supply which leads to increasing the production of construction waste. Recycle Concrete Aggregate (RCA) was proposed as the one of the component in the pervious concrete for sustainability in the construction industry to reduce the wastage. The pervious concrete was function as a medium to allow the water penetrate through porosity of the concrete and avoiding water from pooling at the surface. Therefore, this study is conducted to investigate the properties of the pervious concrete by infiltration test and compression strength test using Recycle Concrete Aggregate (RCA) and Natural Aggregate (NA) as the main composition. The cement aggregate ratio of 1:3 and 1:5 were choosing as variable to produce the workability pervious concrete that similar to conventional concrete. The replacement of NA with RCA is likely a viable option for structural use.

Waste Management at Construction Sites in the Municipality of Manaus, Amazonas, Brazil: Characterization of the Current Situation

This research aimed the characterization of the current production of construction waste in the city of Manaus, Amazonas, Brazil, and its impacts on the environment of the Amazon Region. The significance of this research work is to contribute to the improvement of the environmental management of waste in the construction sites of the city of Manaus, with the aim of preserving the Amazonian environment. This research also sought to characterize the existing problems in the environmental management of construction waste in four construction sites, with areas greater than 9,000 square meters. The methodology adopted was based on the application of an in situ survey in four construction sites in the city of Manaus, Amazonas, Brazil, administered by three companies representing the construction sector in the Amazon Region. Data were collected at the construction sites in question in the second half of 2018, regarding the types of construction waste produced, respective volumes, destination and associated costs. A comparison was made between constructed areas and volumes of waste produced, characterizing the current situation of construction waste production in the city of Manaus. After analysing the results obtained, it was concluded that due to the high associated costs, companies avoid recycling construction waste, and opt to discharge it in municipal or clandestine landfills, with significant environmental impacts. For this reason, a greater participation of the Public Administration is recommended regarding the adequate management of waste in construction sites, namely offering financial incentives for companies to promote the recycling and reuse of construction waste.

Spatially explicit material stock analysis of buildings in Eastern China metropoles

China is experiencing a period of rapid urbanization and fervent construction activities, which are responsible for the accumulation of large amount of material stocks (MS). Fundamental in every society, buildings not only shape material flows before and during construction, but also during maintenance and demolition, inducing the extraction of resources and the production of construction waste. It is thus imperative to understand the amount, composition, and location of current building MS as a first step to design appropriate management strategies for an environmentally sustainable society. This research uses the latest GIS dataset of buildings in 14 representative Eastern China metropoles to quantify the current status of building MS by employing a bottom-up method. The selection of the study areas relies on the law of the primate city, which permits to quickly target the most important urban areas of a region. We review and discuss existing material intensity (MI) coefficients for Chinese buildings, and produce a new set of MIs manipulating those available in the literature. We then calculate the total MS, MS density, and per capita MS for each city. Results find that in 14 cities 7.9 Gt of building materials are currently stored in a total area of 3790 km2, resulting on an average density of 2.1 Mt/km2. The per capita building MS results being 283 t/cap, and this value correlates with a growth of the per capita GDP. We conclude the research with a hotspot analysis of the spatial distribution of the MS, identifying the MS clusters.

AHP comparative analysis of construction and demolitio (C&D) waste recycling scenarios: The case of Beijing

As construction waste production inBeijinghas increased significantly, there is an urgent demand to manage and dispose it in a more economical and environmentally-friendly way. As there are different benefits and limits between preliminary sorting/recycling on construction sites and centralized treatment on final disposal sites, three scenarios were formed. AHP was used to compare these scenarios from the aspect of technical feasibility, economic costs and environmental effects. AHP analysis results showed that the priority of three scenarios followed D3>D1>D2, indicating the optimal way for C&D waste in Chaoyang district is firstly going through primary recycling with a mobile treatment facility on the construction site and then transporting to a final disposal site.