A Building Information Modeling-Life Cycle Cost Analysis Integrated Model to Enhance Decisions Related to the Selection of Construction Methods at the Conceptual Design Stage of Buildings

Life Cycle Cost Analysis (LCCA) provides a systematic approach to assess the total cost associated with owning, operating, and maintaining assets throughout their entire life. BIM empowers architects and designers to perform real-time evaluations to explore various design options. However, when integrated with LCCA, BIM provides a comprehensive economic perspective that helps stakeholders understand the long-term financial implications of design decisions. This study presents a methodology for developing a model that seamlessly integrates BIM and LCCA during the conceptual design stage of buildings. This integration allows for a comprehensive evaluation and analysis of the design process, ensuring that the development aligns with the principles of low carbon emissions by employing modular construction, 3D concrete printing methods, and different building design alternatives. The model considers the initial construction costs in addition to all the long-term operational, maintenance, and salvage values. It combines various tools and data through different modules, including energy analysis, Life Cycle Assessment (LCA), and Life Cycle Cost Analysis (LCCA) to execute a comprehensive assessment of the financial implications of a specific design option throughout the lifecycle of building projects. The development of the said model and its implementation involves the creation of a new plug-in for the BIM tool (i.e., Autodesk Revit) to enhance its functionalities and capabilities in forecasting the life-cycle costs of buildings in addition to generating associated cash flows, creating scenarios, and sensitivity analyses in an automatic manner. This model empowers designers to evaluate and justify their initial investments while designing and selecting potential construction methods for buildings, and enabling stakeholders to make informed decisions by assessing different design alternatives based on long-term financial considerations during the early stages of design.

Investigation of the Severity of Modular Construction Adoption Barriers with Large-Scale Group Decision Making in an Organization from Internal and External Stakeholder Perspectives

Modular construction as an innovativemethod aids the construction industry in transforming to off-site construction production with high efficiency and environmental friendliness.Despite the obvious advantages,the uptake of modular construction is not booming as expected.However,previous studies have investigated and summarized the barriers to the adoption ofmodular construction.In this research,a Large-ScaleGroupDecisionMaking(LSGDM)-based analysis is first made of the severity of barriers to modular construction adoption from the perspective of construction stakeholders.In addition,the Technology-Organization-Environment(TOE)framework is utilized to identify the barriers based on three contexts(technology,organization,and environment).The Technique for Order Preference by Similarity to Ideal Solution(TOPSIS)and LSGDM models are both implemented for the first time to analyze the severity of the barriers to modular adoption based on questionnaire results from internal and external stakeholders in an organization.Finally,in this research,in-depth insights into the severity of barriers are gained,providing a reference for construction organizations to manage modular adoption.

Toward modular construction of cell‐free multienzyme systems

The implementation of multiple enzymes for chemical production in a cell‐free scenario is an emerging field in biomanufacturing.It enables the redesign and reconstitution of new enzymatic routes for producing chemicals that may be hard to obtain from natural pathways.Although the construction of a cell‐free multienzyme system is highly flexible and adaptable,it is challenging to make all enzymatic reactions act in concert.Recently,modular construction has been conceptual‐ized as an effective way to harmonize diverse enzymatic reactions.In this review,we introduce the concept of a multienzyme module and exemplify representative modules found in Nature.We then categorize recent developments of synthetic multienzyme modules into main‐reaction modules and auxiliary modules according to their roles in reaction routes.We highlight four main‐reaction mod‐ules that can perform carbon metabolism,carbon assimilation,protein glycosylation and nonribo‐somal peptide synthesis,and exemplify auxiliary modules used for energy supply,protection and reinforcement for main reactions.The reactor‐level modularization of multienzyme catalysis is also discussed.

Cyclic Shear Tests on Key Connection Joints of Modularized Constructions

Modularized construction is a new type of prefabricated building system with green environmental protection and excellent performance. There are few studies on the seismic performance of its key connection joint. This paper presents a new type of assembled connection joint for the high-rise modularized construction. Cyclic shear tests of full-scale joints were carried out, and the key indexes of their seismic performances including the hysteretic performance, ductility, and energy dissipation capacity were analyzed and obtained. The results show that the hysteresis loops of longitudinal and lateral cyclic shear tests were both plump in shapes. The ductility coefficients were 4.54 and 4.98, and the energy dissipation coefficients were 1.83 and 1.43, respectively. The test joint had good ductility and energy dissipation capacity. The positions of yield failure of specimens were mainly concentrated in the connection areas between the column and short beam or end-plate. The research can provide the technical reference for the seismic design and engineering application of related modularized constructions.

Modular Disruption in Construction Industry-The Environmental Benefits

The impact of Covid-19 on every aspect of life is undeniable.As the pandemic began to spread throughout February 2020,no one could have foretold the ways in which this disease would change society.One of the key things that the Covid-19 pandemic has accelerated is off-site manufacturing and the different ways in which modular construction can be utilized to deal more effectively with the demands of a crisis.The rapid erection of modular hospitals across the globe has been critical in fighting the outbreak of Covid-19,not least the modular hospital in Wuhan that was built in just 10 days.Modular construction was already a hot topic for the industry,the pandemic has simply enhanced this-and the last few months were given the opportunity to explore the options in more detail.There is no doubt that modular construction will continue to play a part in construction projects in the longer term and construction industry should adapt to accommodate this change.Since construction industry is the largest consumer of natural resources,this article would emphasize on the sustainability dimensions of modular construction and its performance during the whole lifecycle.A thorough literature review of the sustainability benefits of modular construction compared to its tradition counterpart is presented.

Development of L-Type Fixation Equipment for Transporting Unit Modules

The unit modular technique is one in which unit modules are prefabricated in a factory and then constructed at a construction site. That is why an important process, transport of unit module, is added in this technique. However, it is not easy to transport a unit module that is high prefabrication ratio （prefab. ratio） （70-90%）, since the walls and interior and exterior materials installed in it can become broken when the unit module is fixed using general fixation tools, including ropes and fixing belts. When the external wall, windows, etc. are damaged during the transportation, the efficiency of unit modular method is deteriorated. Taking this into account, the purpose of this study is to develop an improved fixation device that is convenient for fixing a unit module with a high prefab, ratio to a vehicle and securing the safety while running. The L-type adapter block proposed in this study was evaluated the structural safety through simulation method. The result of the simulation is that it seems desirable to set the working load of the L-type adapter block as 15 kN for Case 1 and 30 kN for Case 2. Therefore, when the L-type adapter block is utilized under the conditions in which the same load is applied as in Case 2, it is expected that safety will be improved.

Modular Plaster Blocks with a Low Environmental Impact

Plaster is a binder which, compared with other materials as lime and cement Portland, can be considered much less aggressive to the environment. While, in the process of production, Portland cement and lime emits CO2, plaster emits molecules of water in the atmosphere. While the production of lime and cement Portland requires high temperature, plaster needs only 150~C. In spite of these environmental advantages, plaster is relatively little used in Brazil and in the rest of South America. An effort has been made to increase the consumption of this material in housing. In this work, a constructive system was developed using plaster blocks. This rationalized system looks for to reduce the manpower considerably, the times of execution and, consequently, the final costs of the construction. The basic components are three types of main blocks, and from these main blocks, sub-blocks are obtained, so that all the dimensions of the construction are achieved. All the dimensions of blocks, sub-blocks and construction are multiples of the base-unit, 10 cm, basic principle of the modular coordination. So, waste of material is avoided. The blocks developed and the constructions way are presented.

Ralph Rapson’s Greenbelt:The Evolution of a Prototype

During the first decade of the 21st century,responding to a renewed public interest in modern prefabricated residential design,Ralph Rapson adapted his 1945 Case Study House#4 into a family of prototypical modular house designs marketed by Wieler LLC.Like the original design,the modular designs are organized around a central daylit“greenbelt”.At the time of Rapson’s death in 2008 the modular greenbelt line included a range of prototypes from 570 to 2,700 square feet.The original Arts&Architecture Case Study House Program was defined by John Entenza around five core principles,which notably included design prototypicality and incorporation of contemporary developments in the building industry.The five Case Study House principles structure this analysis of the array of Greenbelt designs Ralph Rapson adapted to modular construction and the 21st century market response to their production.Over four years and hundreds of customer inquiries,the Greenbelt family of prototypical designs grew four times larger than the number of built examples,suggesting that design and manufacturing strategies which facilitate adaptation to specific project needs are important characteristics for success in the contemporary modular residential market.

RELOCATABLE MODULAR BUILDINGS FOR A SHORT-TERM INTERNATIONAL EVENT:THE PYEONG-CHANG WINTER OLYMPIC GAMES

Modular methods based on the use of prefabricated structures are increasingly popular for construction projects as they contribute to sustainability by reducing waste and maintenance costs as well as improving time efficiency.For short-term international events,the use of relocatable modular buildings is a potential solution to the problem of“White Elephant”structures built specially for the events that serve no useful purpose once the event is over.This paper focuses on a representative relocatable modular project created for the 2018 Winter Olympic Games in South Korea using a single case study approach to develop an in-depth understanding of the advantages and disadvantages of relocatable modular construction from a practitioner’s perspective and examine how this approach supports sustainability and the Olympic legacy.Important considerations are identified for each of the five main stages:1)planning,2)design and engineering,3)manufacturing,4)construction and 5)disassembly and reconstruction.These findings show how the use of relocatable modular facilities can be a useful approach for international events.

Trend of Standardized Design and Modular Construction for Secondary System of Smart Substations

Smart substation projects have been developed for nearly five years; it is necessary to unscramble the technology route in the whole process in order to provide a direction for the development of engineering construction. Based on the actual status quo of design and construction of the secondary system, the authors analyze the existing problems and the situation, and discuss the trend of standardized design and modular construction of smart substations.

Restoration of hyper-eutrophic water with a modularized and air adjustable constructed submerged plant bed

A modularized and air adjustable constructed submerged plant bed(CSPB)which can be used to restore the eutrophic water is introduced in this paper.This plant bed helps hydrophyte grow under poor conditions such as frequently changed water depth,impaired water transparency,algae bloom and substantial duckweed in summer,which are not naturally suitable for growing hydrophyte.This pilot study in Waihuan River of Tianjin,China,revealed that reduction of Chemical Oxygen Demand(COD),Total Nitrogen(TN)and Total Phosphorus(TP)by the use of CSPB could be reached 30%-35%,35%-40%,30%-40%respectively in the growing season(from March to October)and 5%-10%,5%-15%,7%-20%respectively in the winter(from November to February)when the detention time was 6 d.The relationships between the concentration of COD,TN,TP and the detention time fit the first-order kinetic equation well and the coefficients of determination(R^(2))were all above 0.9.The attenuation coefficients k of the kinetic equation were a function of the water temperature.When the water temperature was quite low or quite high,k was not significantly changed with increasing or decreasing water temperature.While when the temperature was in a moderate range,an increase or decrease of water temperature would lead to a rapid increase or decrease in k.