Reduce Construction Costs Research Articles

CO2 emission and construction cost reduction effect in cases of recycled aggregate utilized for nonstructural building materials in South Korea

The construction industry is a major consumer of natural resources and a major waste generator. The use of recycled aggregate is important for the environmental sustainability of the construction industry because it can not only reduce the need for waste landfills, but can also reduce the depletion of natural aggregates. Although there are many studies on the environmental effects of recycled aggregate, there are few studies on its practical effects as applied to real buildings. Recycled aggregates have not been widely used owing to a lack of user trust. Generally RCA has been commonly used in nonstructural materials (such as pavements or filling materials) owing to its inherent properties. Due to inferior characteristics of RCA, there is a limit to being widely used as a structural material immediately. Therefore, to expand the use of recycled aggregate, it is necessary to study the economic and environmental benefits from using recycled aggregate as a nonstructural material for buildings. In this study, the cost and potential embodied CO 2 (ECO 2 ) emission benefits were analyzed by using recycled aggregates as the nonstructural materials in four types of buildings, including apartments with 31 different characteristics. When applied RCA to the apartments, the cost savings are -$122,057 which is 10% reduction compared to original material. And the ECO 2 emissions cost savings amount to -$2,958 which is 5% reduction compared to original material; these represent the most effective case and reflect a −0.158% change in the total construction cost.

A study on the wave reflection coefficient near berthing facilities

Introduction. The article deals with the experimental studies on values of the wave reflection coefficient near the structures of berthing facilities with a front vertical wall. The authors present the findings of experimental studies conducted in the form of physical modeling.
 Materials and methods. The method of physical modeling was employed to conduct the experimental studies. These studies are an integral part of the research project that benefits all modern large marine cargo facilities being designed. The method of physical modeling, applied to port facilities, allows obtaining a model wave, identical to that of a full-scale object, and studying interaction between waves and designed hydraulic engineering structures within a pre-set time range. Experiments were conducted in a wave flume of the Hydraulic Engineering Centre for Research and Experiments at NRU MGSU. The most advanced measuring equipment, produced by Wallingford (UK), was used in the experiment.
 Results. As a result of the experiment, the authors obtained values of the coefficient of reflection of waves near a berthing facility with a vertical front wall (the bulwark type of the berthing structure), subjected to the impact of a standard storm. The main Russian regulatory document, SP (Construction regulations) 38.13330.2018 doesn’t have information about the definition of the wave reflection coefficient for all types of hydraulic structures, and the information available there is not exhaustive. The availability of information about the exact values of the wave reflection coefficient for various types of hydraulic structures, such as berthing facilities, can reasonably reduce their elevation, that will ultimately lead to a substantial reduction in construction costs and time.
 Conclusions. The results of these scientific studies will ensure the successful implementation of the most recent designs of seaports, terminals and cargo complexes in unfavourable natural environments, including the harsh climate of Arctic latitudes, regions where raw hydrocarbons and liquefied natural gas are intensively extracted. This will help to solve the priority task of our time: construction of new transshipment facilities along the Northern Sea Route.

BIM Digital twins environment to enhance construction process

Nowadays, the quality of life is mostly related to the quality of construction. Poor performance of construction project could be related to the poor quality of used construction materials but also to the unsuitable construction processes. BIM methodology adopted an innovative and more effective workflow in construction process. Benefits of BIM are widely recognized and documented including enhanced communication and collaboration between stakeholders, effective decision-making and monitoring, reduced construction cost and duration, etc. However, there is a lot of construction process related information outside of BIM methodology like ERP and building automation system. Digital Twins (DTs) contribute to smart construction through the integration of artificial intelligence, machine learning and data analytics. As construction projects are getting more complex and need more advanced and integrated tools to achieve economic and sustainability objectives, this work proposes a new construction system using the power of digital twins (DTs) and BIM to improve construction process. Genetic algorithm is used to optimize repetitive floor construction cycle. it is reasonable to expect a reduction of 25% of unused resources, which greatly improves site productivity and obtain better economic efficiency. In addition, the working and safety conditions of workers are improved since daily rates of working hours are balanced.

The Application of Speech Synthesis Technology Based on Deep Neural Network in Intelligent Broadcasting

To improve the sound quality of speech synthesis technology in intelligent broadcasting, a deep neural network-based method is proposed. It also proved the effectiveness of the DNN discrimination s/u/v and completed the conversion of the HMM synthesis spectrum parameter to original speech. Further, the scheme for transforming the parameters obtained from the temporary decomposition (TD) algorithm, DNN trains the event vectors obtained from TD decomposition, establishes the transformation model, and recombines with the untransformed event function. Experiments proved that the conversion effect of 16 dimensional parameters is not very ideal in subjective evaluation due to the fact that too few dimensions lead to insufficient spectral details, and the distortion in the process of further synthesis; the parameter conversion of 48 dimensions is slightly better than 16 dimensions, mainly due to more spectral details, but on the other hand, the influence of codebook mapping also affects the sound instability to some extent. It proves that the intelligent voice broadcast system completely solves these problems, which not only reduces construction costs, but also improves service efficiency.

Backward Integration as a Business Strategy to Increase Company Profitability

PT. Graha Alam Indo Sentosa is a developer operating in the real estate industry. Budiman Napitupulu and his son Binsar Napitupulu founded the company in 2017 in Semarang, Central Java. The organization prefers to construct housing zones for low- to middle-income people. The program is known as "Perumahan Bersubsidi." PT. Graha Alam Indo Sentosa is in the process of constructing a residential community (Perumahan the Sambeng Village) in Pemalang Regency, Central Java. The overall area to be developed is 5,6 hectares and will feature around 530 homes and 37 stores. The developer has built and sold 220 residences and five shops as of November 2021. As part of its backward integration business strategy, PT Graha Alam Indo Sentosa owned the business unit Sambeng PreCast in order to reduce construction costs. The business unit is intended to assist the corporation in generating the building materials needed to create houses, roads, and water channels. This research will elaborate on the success of the backward integration approach and whether or not it can significantly contribute to the company's sales and profits. Based on the discussion in the all chapters available (business exploration, business solution,and financial analysis), profitability has been positively benefited by the backward integration business plan followed by PT Graha Alam Indo Sentosa via the business unit (Sambeng PreCast). Using a backward integration strategy, the corporation can reduce building costs (COGS) and improve revenues and profits automatically. So, the company is advised to continue or even expand the backward integration business strategy.

Backward Integration as a Business Strategy to Increase Company Profitability

PT. Graha Alam Indo Sentosa is a developer operating in the real estate industry. Budiman Napitupulu and his son Binsar Napitupulu founded the company in 2017 in Semarang, Central Java. The organization prefers to construct housing zones for low- to middle-income people. The program is known as "Perumahan Bersubsidi." PT. Graha Alam Indo Sentosa is in the process of constructing a residential community (Perumahan the Sambeng Village) in Pemalang Regency, Central Java. The overall area to be developed is 5,6 hectares and will feature around 530 homes and 37 stores. The developer has built and sold 220 residences and five shops as of November 2021. As part of its backward integration business strategy, PT Graha Alam Indo Sentosa owned the business unit Sambeng PreCast in order to reduce construction costs. The business unit is intended to assist the corporation in generating the building materials needed to create houses, roads, and water channels. This research will elaborate on the success of the backward integration approach and whether or not it can significantly contribute to the company's sales and profits. Based on the discussion in the all chapters available (business exploration, business solution,and financial analysis), profitability has been positively benefited by the backward integration business plan followed by PT Graha Alam Indo Sentosa via the business unit (Sambeng PreCast). Using a backward integration strategy, the corporation can reduce building costs (COGS) and improve revenues and profits automatically. So, the company is advised to continue or even expand the backward integration business strategy.

Generation of optimal (de)centralized layouts for urban drainage systems: A graph-theory-based combinatorial multi-objective optimization framework

• A novel graph-theory-based framework for sewer layout creation is developed. • A generic scheme for decentralized layouts in flat and steep terrains is suggested. • Three layout objective functions are put forward for discarding the feasible layouts. • Layout decentralization could largely reduce the construction costs of the final network. • Layout decentralization could largely improve the resilience response of the network. The suitability and effectiveness of decentralized paradigms in the field of underground conveyance drainage infrastructures for coping with the current and upcoming sustainability and resilience demands has been documented in recent research. However, a generic and holistic framework that can be quickly put in practice is lacking. To this end, this study proposes a scheme for creating and optimizing decentralization scenarios in terms of sewer layout configurations for both flat and steep terrains with the aid of a combinatorial graph-theory-based optimization. Additionally, a novel and generalized formula is derived to determine the degree of centralization coupled with three layout objective functions, thereby eliminating several feasible layout solutions. The results indicate that cherry picking an appropriate sewer structure (topological layout) at the planning stage can largely influence the design construction costs (reduction up to 49% for steep terrain and 25% for flat terrain), as well as the resilience response of the final network. Therefore, as a general rule of thumb, breaking down the centralized network into a decentralized one can reduce construction cost and improve resilience.

Lean Methodology in Reducing Construction Costs

Lean Methodology in Reducing Construction Costs

High sensitivity metal-insulator-metal sensor based on ring-hexagonal resonator with a couple of square cavities connected

The necessity for cheaper and more efficient sensors has been the main motivation for the use of Metal-Insulator-Metal (MIM) sensors. In this paper, a micro-dimensional refractive index MIM sensor based on surface plasmon polaritons is presented. This sensor has a ring-hexagonal resonator and a pair of squares-ring resonators that are connected to each other. For the proposed structure, magnetic field profile, transmission spectrum, and important sensor parameters such as sensitivity are obtained through the finite-difference time-domain (FDTD) method. By optimizing the dimensions of the resonators, we achieved a sensitivity equivalent to 2115 nm/RIU in the first mode and 2180 nm/RIU in the second mode. The FOM values for the first and second modes were 118.25 RIU−1 and 120.208 RIU−1, respectively. The results show that the ring-hexagonal resonator significantly improves the sensor parameters in both modes. These enhancements can be considered unique due to the simple structure presented and as a result the reduction of construction costs.

Critical Obstacles in the Implementation of Value Management of Construction Projects

At present, the construction industry in China has problems such as low production efficiency, low technical efficiency, low management efficiency of the construction project, delayed delivery, budget overruns, and unreasonable risk allocation. Value management can address these issues by enhancing the value of construction projects in China, reducing construction costs, and ensuring significant investment returns. This study uses literature analysis to identify the critical obstacles to adopting value management and uses questionnaires and surveys, structural equation modeling, and factor analysis to prioritize the critical obstacles to adopting value management. What is more, the main contribution of this research is to identify the critical obstacles to the adoption of value management, which provides a new perspective for related research and has specific positive significance for practice summary and reform direction. The research was limited to the region of Tianjin and its surrounding cities. The critical survey respondents for this study are architects, quantity surveyors, contractors, civil engineers, and service engineers with rich experience in construction management. The research results show that the key obstacles to implementing value management in the construction industry in China are mainly divided into four categories: Environmental Factors; Stakeholder and Management Factors; Technological Factors; Information Factors. In addition, the researchers found that the level of the adoption of value management in the construction industry in China is deficient. Value management was not used in most of the organizations surveyed, and project teams did not practice its concept.

Construction Operations Practices and Operations Research Tool Application in a Hypothetical Construction Project

This study aimed to assess the construction operations practices of three contractors; apply the construction operations practices for each company to a hypothetical construction project; and use an operation research tool in the hypothetical construction project. The results showed that the majority of contractors have similar organizational delivery systems with functional departments such as business development, finance, human resources, and construction operations, and they fall into the PCAB group. According to respondents, efficiency in resource use, avoidance of non-conformance works, elimination of wastes or non-value-added activities, value engineering, bulk order discounts, listing of different suppliers, double shifting of work scheme, prioritizing activities suitable for weather conditions, delegating work packages to subcontractors, resequencing the project schedule, application of value engineering are all important factors in optimizing project costs. The study concludes that operations research methods are important in project management, particularly in terms of reducing construction costs and increasing project profit. The findings indicated how the operations research tool, in conjunction with the QM for Windows application, made determining project schedule priorities to manage large and complicated project operations appear simple.

Layout, Topology, and Size Optimization of Steel Frame Design Using Metaheuristic Algorithms: A Comparative Study

Determining the topology, layout, and size of structural elements is one of the most important aspects in designing steel seismic-resistant structures. Optimization of these parameters is beneficial to find the lightest weight of the structure, thus reducing construction cost. This study compares the performance of three metaheuristic algorithms, namely, Particle Swarm Optimization (PSO), Symbiotic Organisms Search (SOS), and Differential Evolution (DE). Three study cases are used in order to find the lightest structural weight without violating constraints based on SNI 1726:2019, SNI 1729:2020, and SNI 7860:2020. The results of this study show that SOS has better performance than other algorithms.

Appraisal of the housing delivery mandate of selected government agencies in Nigeria

In spite the concerted efforts made by housing stakeholders in formulating and implementing the 2012 National Housing Policy to bridge the gap between housing demand and supply, the housing situation remains in crisis and hampering on existing policies, sustainable housing delivery with consequent socio-economic, environmental, and political implications. These challenges call for an appraisal of the 2012 National housing policy towards identifying effective mechanism for the policy’s implementation. This paper assessed the roles of the housing policy’s implementing agencies (Federal Housing Authority and Federal Mortgage Bank of Nigeria), identify the challenges faced by the agencies and provide strategies for effective implementation of the National housing policy in Nigeria. In conducting this study, a mixed methods approach was adopted. The study identified the roles played by the designated agencies towards ensuring effective implementation of the National housing policy to include facilitating the development and management of real estate across all states, provision of sites and services for all income groups. Some of the major challenges found to be affecting the provision of adequate housing include increasing cost of procuring land and building materials, poorly developed mortgage finance system and high interest rates on mortgages and cumbersome building plans approvals processes. Though the agencies made concerted efforts in living up to their responsibilities, the efforts are not enough as housing deficit continues to increase. It is therefore suggested that all the tiers of government should ensure the provision of adequate infrastructure and appropriate land titles for both implementing agencies and private firms, create enabling environment for private sector participation in long-term housing finance and encourage the use of indigenous and alternative building materials to reduce construction cost.

New running gear for improving the lateral dynamic characteristics of rubber-tired light rail vehicles

Rubber-tired light rail vehicles are generally operated on lines which include a number of small curves, steep slopes, or track switching sections to reduce construction costs or to place multiple stations in densely populated areas. Recently, the tendency is to increase acceleration, deceleration, and operation speed to shorten travel time and to increase transportation capacity. These track characteristics and operation patterns may result in deteriorating lateral dynamic characteristics in rubber-tired light rail vehicles. Therefore, running gear in rubber-tired light rail vehicles needs to play a role in effectively damping lateral vibrations and shock transmitted from the guidance rails through the guidance wheels. In this paper, new running gear was proposed to improve the lateral vibration and ride comfort in rubber-tired light rail vehicles. The new running gear has been newly installed with lateral rubber shock absorbers that can dampen lateral vibration on curved routes. In addition, it has been installed with a bi-directional return spring in place of the existing restoring coil spring and hydraulic damper to improve lateral vibration on straight routes. The effect of improving the lateral dynamic characteristics of the new running gear was verified through dynamic analysis and actual vehicle driving tests (field tests).

Improvement of the performance of NSGA-II and MOPSO algorithms in multi-objective optimization of urban water distribution networks based on modification of decision space

Water distribution networks require huge investment for construction. Involved people, especially researchers, are always seeking to find a way for decreasing costs and achieving an efficient design. One of the main factors of the network design is the selection of proper diameters based on costs and deficit of flow pressure and velocity in the network. The reduction in construction costs is accomplished by minimizing the diameter of network pipes which leads to the pressure drop in the network. Supplying proper pressure in nodes is one of the important design principles, and low pressure will not provide a complete water supply at the consumption site. Therefore, in this research, the problem of optimization in several sample networks was defined with the objectives of cost minimization and minimization of pressure deficit in the whole network. The EPANET software was used for hydraulic analysis of sample networks, and the multi-objective optimization process was performed by coding NSGA-II and MOPSO algorithms in the MATLAB software environment and linking them to EPANET. The cost function was initially defined only by considering the relationship between cost and diameter and the length of pipes, and in the next definition, the cost resulted by violation of the allowable pressure range was added to this function In both cases, the schedule for achieving the optimal answer was executed. The results showed that these algorithms have a high ability to find optimal solutions and are able to optimize the network in terms of cost and pressure by finding the appropriate pipe diameter. The time for reaching convergence was reduced by considering the cost of violation of the allowable pressure limits significantly and the optimal answer is obtained in a small number of repetitions. In NSGA-II and MOPSO algorithms in two-looped network with 20 and 30 iterations and run time of 0.66 and 0.8 s, respectively, and in Lansey network with 150 and 250 iterations and run time of 5.7 and 9.5 s, the optimal solutions were obtained.

Microbial Fuel Cell for Wastewater Treatment as Power Plant in Smart Grids: Utopia or Reality?

Microbial fuel cells (MFCs) have undergone great technological development in the last 20 years, but very little has been done to commercialize them. The simultaneous power production and wastewater treatment are features those greatly increase the interest in the use of MFCs. This kind of distributed power generation is renewable and friendly and can be easily integrated into a smart grid. However, there are some key issues with their commercialization: high construction costs, difficulty in developing high power structures, MFC lifespan, and maintaining a high level of efficiency. The objective of this article is to explore the possibilities of using MFCs in urban wastewater not only regarding the technical criteria of their application, but also mainly from an economic point of view, to determine the conditions through which the viability of the investment is ensured and the possibilities of their integration in a smart grid are identified. Initially, this article explores the implementation/configuration of a power plant with MFCs within an urban wastewater treatment plant on a theoretical basis. In addition, based on the corresponding physical quantities for urban wastewater treatment, the construction and operational costs are determined and the viability of the investment is examined based on classic economic criteria such as net present value, benefit–cost ratio, internal rate of return, and discounted payback period. Furthermore, sensitivity analysis is carried out, concerning both technical parameters, such as the percentage of organic matter removal, power density, sewage residence time, MFC efficiency, etc., and economical parameters, such as the reduction of construction costs due to change of materials, change of interest rate, and lifetime. The advantages and disadvantages of their use in smart grids is also analyzed. The results show that the use of MFCs for power generation cannot be utopian as long as they are integrated into the structure of a central wastewater treatment plant on the condition that the scale-up technical issues of MFCs are successfully addressed.

Research on the Application of Mobile Robot in Timber Structure Architecture

The involvement of robots in building construction is already a global trend. Compared with the current stage of construction in which a large number of people are involved, the stability of the robot construction process will greatly affect the construction efficiency and construction accuracy, thus (1) reducing the impact on the environment, hence saving natural resources with other obvious advantages of natural environmental benefits, and (2) reducing construction costs, therefore reducing the economic and environmental benefits of artificial use. This paper proposes a wooden building construction method using a mobile robot, explores the assembly of continuous building components that exceed the robot’s static workspace, and completes a simulated construction experiment of a wooden building using this construction method. The experiment was used as a basis to address (1) innovations in the way a wooden building is erected that satisfy the construction logic of the mobile robot, and (2) the ability of the mobile robot to accurately assemble building components in space, including the ability to align them with existing components on site. Ultimately, the completion of this experiment and its construction evaluation demonstrated the superiority of mobile robot construction over manual construction in terms of reduced manual use and increased construction efficiency.

APPLICATION OF THE COMBINED APPROACH IN THE ORGANIZATION OF CONSTRUCTION FOR STRUCTURING AND SUBSTANTIATION OF A CYCLE OF DIFFICULT INFRASTRUCTURE PROJECTS

The research hypothesis is based on the assumption that in the context of the digital construction space, it is necessary to create an industry-wide digital platform that automates all stages and procedures of the construction project life cycle, as well as developing a scientific and methodological approach and practical recommendations will allow significantly reduce construction costs and strengthen its competitive position in today's dynamic environment.
 It is substantiated that the digital space of the construction industry (construction projects, construction organizations-participants) in the development of information and communication technologies acquires the features of alternative construction business, which should function in a certain transformed environment of construction development projects. Technologies directly related to design and construction (BIM, augmented reality, laser scanning, etc.) increase the efficiency of investment and construction projects, while digital data analysis systems contribute to a better understanding of construction market trends.
 The operating system is determined by the introduction of fundamentally new updated scientific and applied tools designed to provide the development company with a clear formalization and proper analytical support of the processes of formation, analysis, and productive subsequent administration: the leading innovation of the tools introduced commercial housing construction, which are implemented in a complex economic and managerial format – production-technological, resource-logistical and administrative management of the content of business processes of project cycles as part of the portfolio of housing construction projects of the developer.

EFFECTS OF USING PALM KERNEL SHELL AND SPIKELET FIBERS AS COARSE AGGREGATE FOR LIGHTWEIGHT CONCRETE

Agricultural and Industrial wastes have created waste management and pollution problems. The replacement of conventional ingredients in concrete production would reduce construction cost and proper waste management. The percentages of spikelet fibers in the composites were 0%, 0.25%, 0.5%, 0.75% and 1%. Concrete cubes and rectangular bricks of sizes 150mm x 150mm x 150mm and 40mm x 40mm x 160mm respectively with different percentages of spikelet fibers cured and tested after 7 and 28 days. The flexural strength, compressive strength, Density, slump workability, rate of water absorption and grain size were analyzed. It results that palm kernel shells was well graded and a good replacement for conventional aggregates. The density and compressive strength after 28 days curing were within the range 1645 to 1749kg/m3 and 15.35 to 19.21kg/m3 respectively. It was observed that slump workability reduced while compressive strength, water absorption, density and flexural strength increases proportionately with fiber contents.

Development of cost-effective repair system for locally damaged long-distance oil pipelines

The traditional maintenance method for locally damaged long-distance oil pipeline involves hot work. Tedious technological processes are required to prevent the explosion of oil and gas due to the existence of combustible oil and gas in the pipeline. This study presents and verifies an economical and efficient replacement method for partially damaged oil pipelines. The core of the new method is to inject temporary plugging material to isolate the locally damaged pipeline and then carry out hot work. The temporary plugging material is composed of hydrogel and composite clay. The main function of hydrogel is to push away the residual oil to form an isolated oil and gas area. When the plugging length was 3 m, the hydrogel can resist the maximum pipeline pressure of 29.46 kPa. The composite clay increased the plugging capacity, thereby achieving plugging with pressure. When the plugging length was 2 m, the maximum resistance pressure of the composite clay was 0.49 MPa. The use ratio of the two materials can be flexibly adjusted in accordance with the actual plugging pressure. When the pipeline pressure was greater than the maximum plugging pressure, the plugging area was damaged, and the pipeline resumed transportation. In addition, hydrogels possess excellent heat absorption ability, which can reduce heat transfer during hot work to ensure safety. The hydrogels can be collected from the filtration station after the operation completion and can be recycled after simple treatment to reduce construction costs. The new replacement method of locally damaged oil pipeline has evident advantages compared with the traditional method.