The construction, maintenance and use of housing has a major negative impact on the environment and is currently a major contributor to catastrophic changes in the global climate, atmosphere and ecosystem. To counter these problems, this project will develop a single- and two-story residential building design based on Malaysian codes and practices to analyze the total carbon emission produced. Modern one- and two-story residential buildings were chosen as case studies of this project both for the strategy to reduce total carbon emissions and to optimally design towards a sustainable and green environment.
Eurocode was chosen as the design standard for this project with the typical strength of materials used in reinforced concrete design. Overall, the analysis showed that 15% PFA concrete had a negative design impact compared to normal concrete and 25% GGBS concrete because its equivalent carbon release was higher. By combining waste with concrete without prior analysis of the carbon content, which could have a negative impact on the environment, it justifies the fact that waste is not considered an environmentally friendly material.
Through design and drawings, the amount of materials used in this project accurately determined and simultaneously generates total carbon emissions.
INTRODUCTION
Background of study
The optimal green building design will be effective by mimicking all the natural systems and conditions of the pre-developed site after the development is completed. In Malaysia, a measurement tool has been developed to assess green building, known as the Green Building Index (GBI). It is believed that global warming is mainly caused by greenhouse gas emissions, especially carbon dioxide (CO2) emissions.
According to the World Bank's collection of development indicators, which is derived from officially recognized sources, Malaysia's CO2 emissions were reported at 239,620 kt in 2018. Cement production and fossil fuel combustion both produce carbon dioxide emissions. In 2020, the Covid-19 pandemic devastated the entire world as a nightmare in human health and economic activities.
Therefore, it shows that by limiting economic and development activities, it is possible to protect the earth from all environmental problems such as just an increase in the emission of carbon dioxide and global warming.
Problem Statement
Objective
- Scope of Study
For this project, Revit Software is used to design single and double storey residential buildings. This software is chosen because it is compatible with the Eurocode Standard to be implemented in the design, therefore the Eurocode Standard is adopted in this project as a code of practice. For this study, the characteristics of concrete strength, environmental condition, fire resistance, minimum and maximum diameter of reinforcement and element size are specified for uniformity of design.
LITERATURE REVIEW
- Introduction
- Sustainable Development
- Origin of Sustainable Development
- Sustainable Development Three Main Pillars
- Sustainability Challenges in the Construction Industry
- Sustainable Development Practice in Malaysia
- Sustainable Design Criteria
- Challenges in the Implementation of Sustainable Development
- Carbon Emission Trend
- Definition of Carbon Emission
- Carbon Emission Trend in Malaysia
- Carbon Emission Trends in the Construction Industry
- Carbon Emission Reduction Strategy
- Alternative Material for Concrete
- Fly ash as Value Added Material for Greening Cement
- Blast Furnace Slag as Value Added for Greening Cement
- Green Building Design
- History of Green Building
- Benefits of Green Building Design and Development
- Criteria of Green Materials for Residential Building
In terms of process, BIM has the potential to create a more sustainable environment by reducing time and cost by using 3D models instead of traditional paper drawings. Data-rich BIM models can also be used to replace traditional 2D approaches, enabling seamless integration of information from the beginning to the end of the project lifecycle. The use of building materials has been highlighted as one of the sustainability challenges of the construction industry.
A critical analysis of the global scenario related to global warming, CO2 emissions and the historic transformation in the construction industry, brought forward to highlight the complexity of the issues. The assessment criteria have been established to ensure the excellence of the sustainable design while promoting the adoption of green building design. The high cost of implementing sustainable development in current construction projects is one of the main obstacles.
International Energy Agency research on the energy sector and industrial processes gives about 9.95 GtCO2 of total global emissions from the construction sector. 50 percent of cement demand and 30 percent of steel demand worldwide is accounted for by the building construction industry. Conversely, the housing sector was responsible for about 2,236 metric tons of total carbon emissions, or about 39% of total emissions in the construction industry (H. Ritchie, and M. Roser, 2020).
In addition, adding fly ash to the concrete mixing process can decrease the permeability of the concrete while reducing its voids. Apart from that, it is important to ensure the material quality, execution procedures and treatment process of material to control the performance of the alternative materials in concrete (A. Naibaho, 2018). Rodriguez, 2019, FA material is known as waste material from the burning pulverized coal, where it is one of the easily obtainable and environmentally alternative methods of concrete production.
There are several advantages of FA, including the ability of the concrete mix to produce heat of hydration, which can prevent thermal cracking of concrete. It is a by-product of the coal combustion process that is collected in an electrostatic filter. Each component is considered as one of the primary factors in creating sustainable green buildings.
A green building emphasizes optimizing resource efficiency in the use of resources such as water, energy and materials while minimizing the building's impact on the environment and human health during the project's life cycle.
METHODOLOGY
Selection of Case Study
Furthermore, the selection criteria were based on the current design of the residential building with different floor areas. The project location is in a place with moderate humidity without being exposed to high risk environments. The Eurocode 1992 (EC 2) Code of Practice was used to define the design parameters.
Design life, exposure class and fire resistance, characteristic strength of materials, size of structural elements, minimum cover for durability, fire and connection requirements, and performance evaluation of structural elements were all considered in this project. Therefore, the Class 1 X0 designation was used in this project with no risk of corrosion or attack. Eurocode was chosen as the design standard for this study to determine the typical strength of materials used in the design of reinforced concrete.
The practical application, which depended on the structural components of the building, was used to determine the characteristic strength of the material. The choice of the typical strength of the material refers to Eurocode 1990 on basic requirements and design specifications. The size of the reinforcement used for main reinforcement ranged from 10 to 40 millimeters and for shear reinforcement from 6 to 10 millimeters.
Therefore, Table 5 shows the consideration of the reinforcement diameter for the reinforced concrete design of this study. The size of the structural elements in this study was determined using rules of thumb based on the building types. The element dimensions in the table were the minimum dimensions of the structural elements that were practically used in the design application.
The safety of the action was taken into account when constructing an action that was forced on the structure. Based on the Eurocode Standard, the safety factor of the design was 1.4 for permanent action and 1.6 for variable action.
Comparative Analysis of Concrete Residential Building
Taking of Material Volume
RESULTS AND DISCUSSIONS
- Economic Analysis of Concrete Residential Building
- Total Structural Work Cost Analysis: Double Storey Residential Building
- Total Structural Work Cost Analysis: Single Storey Residential Building
- Economical Score of Reinforced Concrete Residential Building
- Environmental Analysis of Reinforced Concrete Residential Building
- Factors Affecting the Environmental Score of Concrete RC35/45 with 15% PFA
- Significance of Design
Based on the results, it was found that Concrete RC35/45 with 15% PFA gave a higher price for each element because the current market price is higher compared to regular concrete with OPC and Concrete RC35/45 with 25% GGBS cement. Floor and wall elements were found to be the highest contributor to the total structural labor cost because it accounted for 85 percent of the total concrete structural elements in reinforced concrete two-story residential construction. The economic score was determined based on the total cost of the structural elements, which included material costs.
The data presented in this section showed the total cost of the overall project based on structural elements using ordinary Portland cement, fly ash and blast furnace slag. Tables 11, 12 and 13 show the total costs for element column, floor and wall for a two-storey building. Total building costs were calculated from the total costs of the structural elements of one and two-storey residential buildings, including column, floor and wall.
The amount of recorded total costs was compared between normal concrete, concrete RC35/45 with 15% PFA and concrete RC35/45 with 25% GGBS cement. It is important to ensure that each of these factors has a positive impact so that they deliver a high-quality design. Apart from that, the analysis of the economic score of a reinforced concrete structure through the use of alternative materials should take into account the resources of the material and whether it contributes to the additional cost of the material or is free of sources of the manufacturer.
It can be concluded that the impact of cost on the use of material is an important parameter and cannot be neglected in the design of residential buildings. One of the main objectives of structural optimization is to minimize the total cost of the structure. Considering alternative greener materials in terms of production and embodied carbon emission will absolutely lead to the production of a sustainable structure design.
Well-proportioned alternative materials are important in the implementation in the design to ensure the optimal performance of the structural elements. The determination of alternative material as a replacement material proved to be important in eco-efficient reinforced concrete design to ensure a positive impact of the material in the structure. Analysis of the environmental factor in concrete design for residential construction was carried out to integrate the overall analysis with sustainable design criteria.
The method for selecting the best design alternative based on economic and environmental results must assume that the total cost of building the building is equal to the value of the total amount of carbon dioxide (CO2) equivalent emitted during the construction of the building.
CONCLUSION
Fly ash as a supplement as a cement replacement for concrete: a review, Sustainable Civil and Construction Engineering Conference.
