Modular Structure System Research Articles

Salinity’s Shadow: Sustainable Modular Resilience for the Munda Community, Satkhira

Bangladesh is gifted with abundant natural beauty, with rivers, woods, seas, plains, hills, haors, and canals. However, due to its tropical climate, it is prone to several natural calamities, including excessive salinity in coastal areas. Sundarban is one of these coastal areas where reside the Munda community which is one of the 33 ethnic groups of Bangladesh. Originating from India, Mundas are variously dependent on the Sundarbans for both livelihood and religious aspect and consider the Sundarbans as their mother nature. But poverty and calamities limit their participation in social activities and access to necessities like food, education, and healthcare. This paper aimed to evaluate the difficulties the Munda community faces due to salinity and create a modular structural system that was sympathetic to local culture and more cost-effective local resources that would be more resilient to natural disasters. This paper studied the lifestyle and livelihood of the affected munda community of Burigoalini, Satkhira. This paper finds the available construction materials' quality and resilience in connection to saline impacts and local housing characteristics and also focuses on the historical, cultural, and existential aspects of an ethnic group that is facing the risk of extinction.

Performance Evaluation of Architectural Modular Member with Ultra-High-Performance Fiber-Reinforced Concrete for Application

As the modular industry expands, the most widely used building materials are primarily concrete, steel, and wood. However, the use of wood and steel is severely limited compared to concrete for reasons such as durability and economy. To overcome these shortcomings, we aimed to apply ultra-high-performance fiber-reinforced concrete (UHPFRC), which has excellent compressive strength and tensile strength, high durability, and minimal reinforcement with steel fibers. In this study, research was conducted on the development of unit box-type architectural modules using UHPFRC with a compressive strength of 120 MPa and a tensile strength of greater than 7 MPa. Various amounts of steel fibers (Vf = 1.0, 1.5, and 2.0%) were evaluated to determine the optimal mixing ratio of UHPFRC, in which both the durability and mechanical performance were assessed. The compressive strength and tensile strength of UHPFRC were found to be 132 MPa and 10.1 MPa, respectively, while its resistance to chloride penetration averaged 14.47 coulombs, indicating superior durability compared to conventional concrete. To reduce the weight of the unit components of the architectural modular system, both normal concrete (NC) components and UHPFRC were applied. The main variables in the flexural tests were the cross-sectional thickness, steel fiber content, and presence of an insulation material, comprising a total of three variables for evaluating the flexural performance. The application of UHPFRC with a compressive strength of 120 MPa, a cross-sectional thickness of 120 mm, and a 10 mm diameter reinforcement provided a similar performance to that of NC components while reducing concrete usage by 60% compared to NC components. Additionally, structural analysis was performed to prototype the unit box-type modular structure using UHPFRC. The modular structural system developed in this study was found to reduce construction costs by 18.7% compared to traditional steel structural systems. Further research is necessary to address issues such as floor slab vibration and noise, connections, and expansion to multistory buildings for commercialization of modular structures using UHPFRC.

Behavior of a Composite Steel Decking and Boarding System in Fire Based on Large-Scale Experimental Testing and Numerical Modelling

This paper presents experimental and numerical results of an investigation into the thermal and structural behaviour of an innovative modular structural steel system, which includes cellular beams, that was tested in a 1-h standard fire scenario while loaded. The modular system consists of a 5.66 × 3.8 m rectangular steel frame, with a profiled steel sandwich decking (SD) system attached, which comprises of (a) profiled steel decking, (b) fibre cement, and (c) calcium silicate boards and strips. The SD system is suspended from the underside of the horizontal structural members to provide inherent fire protection to the steel beams from the bottom and acts as the load-bearing component of the flooring. The purpose of the experiment was to determine the fire resistance of the structural system, whilst under load, which is primarily based on the fire resistance of the SD system. Temperature data for the SD system was collected during the experiment and used to validate a numerical finite element analysis model. This study shows that the SD system was able to achieve a fire resistance rating of 57 min in the experiment which was governed by insulation resistance. A lower fire resistance rating is estimated based on numerical models. Structural resistance was maintained throughout the test. During preliminary testing structural collapse was observed in a separate experiment which highlights how the system is sensitive to damage to the ceiling boards. Numerical results highlight that thermal bowing and movement may result in changes in thermal interactions between adjacent elements. This paper provides novel large-scale experimental data on a loaded flooring system in fire.

Prefabricated Volumetric Modular Construction: A Review on Current Systems, Challenges, and Future Prospects

Rapid urbanization and population growth worldwide has stimulated the requirement of fast and efficient construction techniques. An emerging trend in the construction industry focuses on prefabricated volumetric modular construction (PVMC), wherein individual room size prefabricated modules are manufactured off-site and transported to the site for assemblage using joint connections. This paper provides a comprehensive review on prefabricated modular structural systems, general concepts, joint connections for steel and concrete modules, and their structural behavior. Further, the impediments in current PVMC systems are outlined and technical challenges that restrict the widespread acceptance of PVMC systems are discussed. PVMC is advantageous over conventional construction with regard to construction efficiency, material optimization, speed, safety, and quality control, along with reduced environmental impact. However, application of PVMC in construction industry is very limited due to lack of sufficient understanding on joint connections, seismic behavior, and design methods. It is inferred that reasonable research has been carried out to study the behavior of connection systems at the local level, while research on global seismic performance of prefabricated modular buildings is scarce, which calls for extensive experimental investigations on full-scale modular buildings subjected to lateral loading.

Exploration of steel structure modular building technology system based on rapid assembly—take X-house for example

Through modular design and modular assembly technology measures, taking function, space and structural system as structural units; Three-dimensional building information technology is applied in design, manufacturing, on-site assembly and other links. The modular technology system of steel structure for rapid assembly such as modular structural system of building space, beam-column nodes, node design optimization, on-site hoisting and assembling of modular building structural system, modular mechanical and electrical equipment unit design and other applications is comprehensively and systematically discussed. Taking X-house project participating in the Dubai International Solar Energy Competition as an example, the research and practice of residential technical system for rapid assembly are systematically introduced.

Hydrodynamic Responses of a Novel Modular Floating Structure System With Multi-Direction Expansion

Abstract In order to comprehensively utilize ocean resources and renewable energy, a novel modular floating structure (MFS) system with multi-direction expansibility has been proposed, which includes inner hexagonal tension leg platform (TLP) modules and outermost floating artificial reef modules coupled with the function of the wave energy converter (WEC). Considering both the hydrodynamic interaction effect and the mechanical coupling effect, the main dynamic responses of the MFS system have been analyzed under different incident wave directions, and the corresponding physical mechanism has been clarified. Results indicate that connector loads slightly increase, but motion responses of the MFS system are more stable when the outermost floating artificial reefs serve as the up-wave modules. Outermost floating artificial reef modules have shown good wave-attenuation capacity for inner TLP modules, as well as producing considerable output wave power. The effect of key power take-off (PTO) parameters on the WECs’ performance has been investigated, and the optimal PTO damping coefficient has been suggested. In addition, extreme responses of the proposed MFS system have been further studied, and its safety has been well verified under typical extreme sea conditions. The main results of this work can serve as a helpful reference for the construction of future offshore floating cities.

Strength of Partially Encased Steel-Concrete Composite Column for Modular Building Structures.

Modular structural systems have been used increasingly for low- and mid-rise structures such as schools and apartment buildings, and applications are extending to high-rise buildings. To provide sufficient resistance and economical construction of the high-rise modular structural system, the steel-concrete composite unit modular structure was proposed. The proposed composite unit modular system consists of the composite beam and the partially encased nonsymmetrical composite column. The outside steel member of the composite column has an open section, and is manufactured using a pressed forming procedure so that easy joining connecting work and manufacturing cost reductions are possible. However, the design methods are complicated due to the inherent nonsymmetrical properties of the section. Therefore, in this study, the focus was made on the strength evaluation and development of design methods for the partially encased nonsymmetrical steel-concrete composite column. Four full-scale specimens were constructed and tested. The experimental study focused on the effect of the slenderness ratio of the column, eccentricity, and the through bars on the strength of such columns. Additionally, the P–M interaction curve to estimate the strength of the proposed composite column under general combined loading was developed based on the plastic stress distribution method. The results indicate that the through bars are needed to delay the local buckling and distribute the loading uniformly throughout the composite column. Finally, the proposed design methods provide a conservative strength prediction of the proposed composite column.

Structural behaviour of a novel modular cellular steel beam system at elevated temperatures based on large-scale experimental testing and numerical modelling

This paper presents experimental and numerical results of a modular structural steel system, encompassing non-composite cellular beams, that was tested using a 1-h standard fire scenario while loaded. The modular system consists of a 5.66 m × 3.8 m rectangular steel frame, with a sandwich decking (SD) system attached, which comprises of a) profiled steel decking, b) fibre cement, and c) calcium silicate boards. The SD system is hung from the underside of the horizontal structural members to provide inherent fire protection to the steel beams from the bottom and is the load-bearing component of the flooring. The aim of the experiment was to determine the structural systems fire resistance because its unusual geometry renders existing full-scale fire test data inapplicable. Novel temperature and deflection data for the system are obtained from the large-scale experiment conducted, which are used to validate numerical finite element analysis models on a single element and global model basis. The numerical and experimental data are compared and show suitable correlation, and highlight some unusual behaviour regarding vertical deformations. From the numerical models and experimental data, it is shown that (a) the structural steel system typically behaves well due to the limited temperature rise as a consequence of the attached SD system, (b) limited plasticity occurred in the system, (c) small axial forces are induced due to the flexibility of the structure, and (d) the system is heavily reliant upon the integrity of the sandwich decking system it supports. Failure of the SD would lead to loss of compartmentation, and potentially structural failure.

Hydrodynamic Analysis of a Novel Modular Floating Structure System Integrated with Floating Artificial Reefs and Wave Energy Converters

A novel modular floating structure (MFS) system moored by tension legs was proposed, which is composed of hexagonal floating modules, floating artificial reefs and wave energy converters (WECs). The integration of floating artificial reefs and WECs into the MFS can improve the marine environment and produce considerable electricity. The effects of both wave characteristics and the module quantity on the hydrodynamic responses of the MFS system were studied in depth, based on a time-domain numerical model. Both the modules’ hydrodynamic interaction effect and the connectors’ mechanical coupling effect were considered. The results indicate that floating artificial reefs combined with WECs can effectively reduce wave loads and convert wave energy into electricity for the MFS system. More modules involved in the MFS system could significantly reduce motion response and produced more wave energy output, which indicates that the MFS system is suitable for large-scale expansion. The effect of different power take-off (PTO) damping coefficients on the WECs’ performance was further investigated, and the optimal damping coefficient was recommended for the MFS system. Finally, the main extreme responses of the MFS system were further investigated, and its safety was checked thoroughly. One survival strategy was proposed, which could efficiently reduce extreme connector loads by more than 50%.

New modular precast composite shear wall structural system and experimental study on its seismic performance

Modular buildings are becoming increasingly popular due to their higher construction efficiency, better quality control and less resource consumption. In this study, a new modular precast composite shear wall structural system was proposed and the joint design principle was given. The new modular precast structural system adopted volumetric concrete modules and dry bolted connections for fully precast construction and demountable ability. This paper presented comparative shaking table tests and comprehensive test result analyses on a modular precast composite shear wall model and a cast-in-place shear wall model. The fundamental frequency of the modular precast model was 10.2% lower than that of the cast-in-place model because of the semi-rigid joints. The modular precast model exhibited comparable dynamic responses with the cast-in-place model, but showed less severe shear wall damage under the same intensity level test due to the small gap opening of vertical joints. The screw fracture and nut slip in vertical joints induced the failure of the modular precast model. The modular precast model exhibited better energy dissipation performance than the cast-in-place model. The adjoining concrete modules could achieve satisfactory synergistic working performance, and the horizontal joints remained elastic throughout the tests. The excellent test performance of modular precast composite shear wall model confirmed the feasibility of the proposed structural system in concrete modular buildings.

The modular structural system as an innovation for temporary public healthcare project of 4th-year architecture students at UIN Maulana Malik Ibrahim Malang

Abstract- The module structure system implements development by utilizing fabricated materials or components made outside the project site or on-site. Consumable shipping containers are often used to make architectural space rated more quickly and efficiently. The advantages of containers are customized, strength, durability, modular, labor, movable, availability, expense, and eco-friendly. The rapid spread of Covid-19 in various regions demands fast, proper, and adequate public health facilities. Containers can be an innovative solution for providing temporary, flexible, efficient, functional, and sustainable public health room facilities. This study describes the uses and advantages of modular container systems for architectural spaces. The result is a schematic design from the design studio of the 4th year architecture student of UIN Maulana Malik Ibrahim Malang, who is trying to improve the function of the use of consumable containers to get more benefits as a temporary architectural space for sustainability and public awareness of health and handling Covid-19.

A New Modular Structural System for Tall Buildings Based on Tetrahedral Configuration

Inspired by the high mechanical performance of diagrid structures, the minimization of material consumption on braced tubes and the expressive potency of tensegrity modular structures, this work proposes an innovative three-dimensional system for tall buildings. A new modular structural system generated from the assembly of tetrahedral units is investigated. The paper integrates insights on the architectural implications and mechanical performance of the reticular system arranged in repetitive triangular-based modules. The impact of different geometric configurations of the structural members on the economic design is also discussed and recommendations for the optimal topology are made. Guidelines for the design and analytical formula for accessing preliminary member sizes are proposed on the basis of stiffness requirements.

MODEL EXPERIMENTAL DE SISTEM TERMIC COMBINAT PENTRU UTILIZAREA EFICIENTĂ A ENERGIILOR REGENERABILE

The article presents an experimental model of a modular structure system for the production of thermal energy and the results of conducting specific tests. The experimental model uses two renewable energy sources - solar energy and energy generated by burning biomass - to provide thermal energy for an increased duration, regardless of the atmospheric factors. Properly sized, the system can be designed as a series product, in a variety of powers, to be used by heat suppliers, and also by individuals, especially the ones from remote areas, who want to ensure their thermal energy independence by using renewable energy.

Study on the stability bearing capacity of multi-column wall in modular steel building

Modular steel building is an innovative structural system composed of volumetric units that are manufactured with full decoration in factory and assembled on site like building blocks. As one type of steel modular structural system, load-bearing modular structural system of the steel multi-column wall has already been put into engineering practice. However, as the stabilizing mechanism of steel multi-column wall is unclear, effective length factor of column in the existing structural design is conservatively taken as 1.0. In this paper, eight tests were performed to investigate the axial stability performance of modular multi-column walls. The results indicated that the modular wall showed good ductility especially for the one that only experienced overall instability; the greater the width-to-thickness ratio of stand column, the easier it’s for local buckling to occur; panel and foamed concrete had minor effects on axial stiffness and ultimate bearing capacity of wall, so they could be neglected in the design. In the end, based on the finite element parametric analysis of steel multi-column wall modular wall, effective length factor of stand columns in the multi-column wall, which could be used in the design, could be obtained. This research could provide a preliminary study on the assessment of the stability capacity of multi-column wall in modular steel building.

Numerical Optimization of Half-Tunnel Concrete Formwork System using FEA

This research seeks to develop a comprehensive framework for the design of Half-Tunnel Concrete Formwork System (HTCFS). HTCFS are highly efficient systems that are used for the construction of modular RCC structural systems. Additionally, HTCFS are significant in terms of higher reuse in constructing modular units. Despite these advantages, the actual design procedure adapted for HTCFS was not well elucidated so far, many companies adapt their own design methodology and hence it is highly important to develop a simplified straight forward design methodology incorporating all comprehensive associated factors. Initially, the detail introspective assessment of various types of HTCFS are perceived. Then using this information, a 3D Solid model is developed, and eventually, the 3D model gets converted into 3D solid CAE model using sophisticated Finite Element package for the Finite Element Analysis (FEA). This procedure is repeated for different combinations of components that construed effective systematized HTCFS. From the FEA the optimal structural components required for the structural integrity of HTCFS are established.

Hydrodynamic analysis of a novel modular floating structure system with central tension-leg platforms

ABSTRACT The present work proposed a novel modular structural system with central tension-leg platforms and outermost wave energy converters (marked as MTLPW). The hydrodynamic interaction effect and the mechanical coupling effect between the WECs and the TLP have been taken into consideration, and the effects of key design parameters of the WEC on the hydrodynamic characteristics of the MTLPW system have been clarified. The results indicate that the outermost WEC can significantly reduce the surge response of the central TLP and produce considerable wave energy. In addition, the effects of different connection types, pretension levels and additional heave plates on the hydrodynamic performance of the MTLPW system have been further investigated, and the results indicate that both the outermost WEC module and the additional heave plate can be promising and available for improving the hydrodynamic performance of the initial MTLPW system.

Engineering modular integrated construction for high-rise building: a case study in Hong Kong

Modular construction has been adopted as a new form of construction to enhance quality and productivity. However, most of the success stories of adopting modular systems are limited to low-rise buildings. This paper explores the feasibility of engineering modular integrated construction systems for high-rise buildings where wind action can be a dominating factor from a structural engineering point of view. Hong Kong was taken as a site for case study in view of the occurrence of high-intensity seasonal typhoons. The systems were hypothesised to adopt a modular system based on an existing 31-storey reinforced-concrete student residence. Three-dimensional finite-element models were developed to investigate the structural behaviours under gravity, wind and seismic actions. The serviceability drift performance, ultimate member strength demand, connection details, overall stability and robustness were compared. The hypothesised building was pushed to a limit of 40 storeys to investigate the structural performance further. The results suggest that the engineered modular structural system is effective to withstand the strong wind and moderate seismic actions demand in Hong Kong, providing a good foundation for exploring innovative structural solutions for high-rise building modularisation.

Parametric Analysis of Vibrations in a Lightweight Two-Way Steel Floor System

AbstractThere is a lack of rapidly constructible, modular, and lightweight structural components and systems used for building construction. Such structures will in the future be able to sustainabl...

Electrically controllable connection and power transfer by electroadhesion

Reconfigurable smart structures and robots require interconnects that enable the transfer of forces, power and data from one modular element to another. This is typically achieved through magnetic coupling, mechanical clips and male–female electrical contacts. In lightweight structures however, these methods are impractical due to weight and complexity. In this work we present an electroadhesive coupling (EAC) controllable interfacial connection for joining lightweight modular components, which enable simultaneous mechanical joining and electrical pass-through connections for power and communication. Active adhesion and power transfer are realized by electroadhesion (EA) using conducting electrodes on lightweight materials such as papers. We present the underlying EAC concept, materials and structures, and demonstrate this new approach using origami and kirigami structures to fabricate a modular EAC bridge and a modular EAC cuboid structural interconnection system. These novel structures have the potential for application in lightweight robotics, space systems, deployable and self-assembling and self-disassembling systems.

Using Modularity to Reduce Complexity of Industrialized Building Systems for Mass Customization

It is widely known that industrialized building systems can positively impact construction projects in terms of efficiency, duration, safety, and quality. Although the use of industrialized building systems can potentially simplify the production process on-site, the complexity of the overall delivery system tends to be high, especially in engineered-to-order (ETO) environments, due to factors such as uncertainty related to goals and methods, conflicts between different trades on-site, and interdependence between supply chain members. This paper explores the concept of modularity, which has proven to be useful in different industries as a way of dealing with complex systems. The aim of this paper is to illustrate how modularity can reduce the complexity of ETO industrialized building systems, in companies that adopt a mass customization strategy. This investigation is based on two descriptive case studies on the development of modular structural steel systems for buildings that have adopted innovative beam-to-column connections. The main contribution of this research is demonstrating the need to adopt an integrated product and process-oriented conceptualization of modularity in industrialized building systems. Moreover, the comparison between the two case studies pointed out that the management of tolerances plays a key role in achieving high productivity and short lead times in structural steel building systems. This investigation also illustrates how the adoption of a limited set of modular components can be used to decouple design decisions, and standardize different types of processes.