Bhupendra Singh Rana, Subhrajit Dutta, Pabitra Ranjan Maiti and Chandrasekhar Putcha
The present study is based on finding the structural response of a tensile membrane structure (TMS) through deformation. The intention of the present research is to develop a…
Abstract
Purpose
The present study is based on finding the structural response of a tensile membrane structure (TMS) through deformation. The intention of the present research is to develop a basic understanding of reliability analysis and deflection behavior of a pre-tensioned TMS. The mean value first-order second-moment method (MVFOSM) method is used here to evaluate stochastic moments of a performance function with random input variables. Results suggest the influence of modulus of elasticity, the thickness of the membrane, and edge span length are significant for reliability based TMS design.
Design/methodology/approach
A simple TMS is designed and simulated by applying external forces (along with prestress), as a manifestation of wind and snow load. A nonlinear analysis is executed to evaluate TMS deflection, followed by calculating the reliability index. Parametric study is done to consider the effect of membrane material, thickness and load location. First-order second moment (FOSM) is used to evaluative the reliability. A comparison of reliability index is done and deflection variations from μ − 3s to μ + 3s are accounted for in this approach.
Findings
The effectiveness of deflection is highlighted for the reliability assessment of TMS. Reliability and parametric study collectively examine the proposed geometry and material to facilitate infield design requirements. The estimated β value indicates that most suitable fabric material for a simple TMS should possess an elasticity modulus in the range of 1,000–1,500 MPa, the thickness may be considered to be around 1.00 mm, and additional adjustment of around 5–10 mm is suggested for edge length. The loading position in case of TMS structures can be a sensitive aspect where the rigidity of the surface is dependent on the pre-tensioning of the membrane.
Research limitations/implications
The significance of the parametric study on material and loading for deflection of TMS is emphasized. Due to the lack of consolidated literature in the field combining reliability with deflection limits of a TMS, this work can be very useful for researchers.
Practical implications
The present work outcome may facilitate practitioners in determining effective design methodology and material selection for TMS construction.
Originality/value
The significance of parametric study for serviceability criteria is emphasized. Parameters like pre-stress can be included in future parametric studies to witness in depth behavior of TMS. Due to lack of consolidated literature in the field combining reliability with deflection limits of a TMS, this work can be very useful for the researchers. The present work outcome may facilitate practitioners in determining effective design methodology and material selection for TMS construction.
Details
Keywords
Dibyendu Adak, Donkupar Francis Marbaniang and Subhrajit Dutta
Self-healing concrete is a revolutionary building material that will generally reduce the maintenance cost of concrete constructions. Self-healing of cracks in concrete structure…
Abstract
Purpose
Self-healing concrete is a revolutionary building material that will generally reduce the maintenance cost of concrete constructions. Self-healing of cracks in concrete structure would contribute to a longer service life of the concrete and would make the material more durable and more sustainable. The cementitious mortar with/without incorporating encapsulates at different percentages of slag replacement with the cement mix improves autogenous healing at different ages. Therefore, this study’s aim is to develop a self-healing cementitious matrix for repair and retrofitting of concrete structures.
Design/methodology/approach
In the present work, waste straw pipes are used as a capsule, filled with the solution of sodium hydroxide (NaOH), sodium silicate (Na2SiO3) and colloidal nano-silica as self-healing activators. An artificial micro-crack on the control and blended mortar specimens at different percentages of slag replacement with cement (with/without encapsulation) is developed by applying a compressive load of 50% of its ultimate load-carrying capacity. The mechanical strength and ultrasonic pulse velocity, water absorption and chloride ion penetration test are conducted on the concrete specimen before and after the healing period. Finally, the self-healing activity of mortar mixes with/without encapsulation is analysed at different ages.
Findings
The encapsulated mortar mix with 10% of slag content has better self-healing potential than all other mixes considering mechanical strength and durability. The enhancement of the self-healing potential of such mortar mix is mainly due to hydration of anhydrous slag on the crack surface and transformation of amorphous slag to the crystalline phase in presence of encapsulated fluid.
Research limitations/implications
The self-healing activities of the slag-based cementitious composite are studied for a healing period of 90 days only. The strength and durability performance of the cracked specimen may be increased after a long healing period.
Practical implications
The outcome of the work will help repair the cracks in the concrete structure and enhances the service life.
Originality/value
This study identifies the addition encapsulates with a self-healing activator fluid that can recover its strength after minor damage.
Details
Keywords
Mrinal Kanti Sen, Subhrajit Dutta and Golam Kabir
Housing infrastructure is the basic need for people of a community and due to disaster many houses may severaly damaged. Stakeholders and decision makers should focus on this…
Abstract
Purpose
Housing infrastructure is the basic need for people of a community and due to disaster many houses may severaly damaged. Stakeholders and decision makers should focus on this issue and make the infrastructure more resilient against natural hazards. As dependency plays a very important role in resilience, it is important to study the dependencies and correlations among the housing infrastructure resilience factors. The evaluation of dependencies involve vagueness due to subjective judgement of experts.
Design/methodology/approach
In this work, the interaction between the housing infrastructure resilience factors are evaluated by using two different approaches such as crisp DEMATEL (Decision-Making and Trial Evaluation Laboratory) and rough DEMATEL (intregated crisp DEMATEL and rough set theory), where rough theory addressed the involvement of vagueness. These two approaches are compared with each other to find the effectiveness of rough DEMATEL over crisp DEMATEL.
Findings
The important factors of housing infrastructure resilience are identified by using both the approaches against flood hazard.
Research limitations/implications
The limitation of rough DEMATEL method is that it does not differentiate the type of influence such as positive or negative.
Practical implications
The outcome of the work will helps the stakeholders and ecission makers to make the infrastructure more resilient.
Originality/value
This study identify the imporatnat resilience factors of housing infrastructure against flood hazard by using two methodologies.
Details
Keywords
Babul Hossain, Md Nazirul Islam Sarker, Guoqing Shi and Md. Salman Sohel
This study intends to assess the research trends on natural disasters and their contribution to the various fields of policy decisions in India by conducting a bibliometric…
Abstract
This study intends to assess the research trends on natural disasters and their contribution to the various fields of policy decisions in India by conducting a bibliometric analysis between 2008 and 2022. The Scopus database was used to extract pertinent literature. The key relevant terms were used to seek relevant papers based on the query of two searches, ‘Natural disaster and India’ scenarios combined by the Boolean operator ‘AND’. Microsoft Excel and VOSviewer-Var1.6.16 were used to assess bibliometric indicators. The database yielded 1,293 papers in all, with 14,584 citations. There were 262 single authors and 1,031 multi-author documents among the publications that were retrieved, with an average of 11.28 citations per document. After 2016, there was a dramatic growth in the total number of publications. The journal articles were the leading source of the particular literature, and this study extracted approximately 858 journal articles from the Scopus database. About 713 and 580 articles were open and closed access, respectively. Earth and planetary sciences (28.07%), social science (31.01%), and environmental science (30.39%) had a higher proportion of papers than other topics. The most impactful authors were Rajib Shaw and Filip K. Arnberg from Keio University, Japan, and Uppsala University, Uppsala, Sweden. Besides, the most funding institutions were from India (39.33%), China (13.11%), and the United States (11.9%) for natural disaster research, in the case of India. The current baseline information on natural disaster-related literature in the context of India showed that this field is growing rapidly but with inadequate research collaboration and low productivity as needed. Research collaboration in this field needs to be strengthened to improve the solid response to natural disasters in any place in India. In addition, there is a need to expand the research focus in this field to include associated indicators.