scholarly journals Effects of Infills in the Seismic Performance of an RC Factory Building in Pakistan

Buildings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 276
Author(s):  
Nisar Ali Khan ◽  
Giorgio Monti ◽  
Camillo Nuti ◽  
Marco Vailati

Infilled reinforced concrete (IRC) frames are a very common construction typology, not only in developing countries such as Pakistan but also in southern Europe and Western countries, due to their ease of construction and less technical skills required for the construction. Their performance during past earthquakes has been in some cases satisfactory and in other cases inadequate. Significant effort has been made among researchers to improve such performance, but few have highlighted the influence of construction materials used in the infill walls. In some building codes, infills are still considered as non-structural elements, both in the design of new buildings and, sometimes, in the assessment of existing buildings. This is mainly due to some difficulties in modeling their mechanical behavior and also the large variety of typologies, which are difficult to categorize. Some building codes, for example, Eurocode, already address the influence of infill walls in design, but there is still a lack of homogeneity among different codes. For example, the Pakistan building code (PBC) does not address infills, despite being a common construction technique in the country. Past earthquake survey records show that construction materials and infill types significantly affect the seismic response of buildings, thus highlighting the importance of investigating such parameters. This is the object of this work, where a numerical model for infill walls is introduced, which aims at predicting their failure mode, as a function of some essential parameters, such as the friction coefficient between mortar and brick surface and mortar strength, usually disregarded in previous models. A comprehensive case study is presented of a three-story IRC frame located in the city of Mirpur, Pakistan, hit by an earthquake of magnitude 5.9 on 24 September 2019. The results obtained from the numerical model show good agreement with the damage patterns observed in situ, thus highlighting the importance of correctly modeling the infill walls when seismically designing or assessing Pakistani buildings that make use of this technology.

2019 ◽  
Vol 3 ◽  
pp. 140-149 ◽  
Author(s):  
Alexis Simons ◽  
Alexandra Bertron ◽  
Christophe Roux ◽  
Aurélie Laborel-Préneron ◽  
Jean-Emmanuel Aubert ◽  
...  

The impact of building materials on the environment and the health of occupants is nowadays a priority issue. Ecological construction materials such as earthen materials are currently experiencing a regain of interest due to both ecological and economic factors. The microbial proliferation on indoor materials can induce a deterioration of the building air quality and lead to an increase of health risks for the occupants. The issue of indoor air quality raises questions about the use of earthen building materials and their possible susceptibility to fungal development. The microflora of earthen materials and their ability to grow on such support are indeed poorly studied. This study focused on the quantification of both bacterial and fungal microflora along the manufacturing process. The impact of extreme humidity, simulating a hydric accident, on microflora development was analyzed on the surface and inside earthen bricks. The initial microflora of these materials was dramatically reduced during the manufacturing process, especially after heat treatment for drying. Proliferation of remaining microorganisms was only observed under high humidity condition, in particular for earthen materials with vegetal aggregates. Moreover, in situ samplings were performed on naturally dried earthen materials used in buildings. The characterization of the microbial density revealed a higher microbial density than on manufactured specimens, while microbial concentration and detected taxa seemed mainly related to the room use and building history. These results provide a better understanding of microbial proliferation on these materials.


2021 ◽  
Author(s):  
Fatiha Imane Mahcar ◽  
Belkacem Takhi

Algeria has a rich urban and architectural heritage, which presents regional specificities. Once the ksour was a symbol of balance and perfect harmony with its environment, unfortunately today they no longer reflect their former function. The Ksourian architecture, including that of Laghouat is a prestigious heritage of high value; it is the testimony of genius knowledge and the capacity of their occupants to adapt to the difficult environment. The housing is considered the essential core of this architecture it represents the entire composition of the ksar, its design is inspired by the immediate environment and respects ancestral social values. It is characterized by a simple architecture and simple construction techniques which are based on the construction in load-bearing walls, the construction materials used are local materials of great resistance and less expensive. This study addresses the theme revaluation of heritage, particularly our case study ksar El-Haouita which has experienced a neglecting and depopulation due to several factors. The ksar El-Haouita is among the most famous ksour located in the south of Algeria and exactly in the region of Laghouat. It is built with simple materials and techniques of construction. The construction materials used are local materials like stones and lime found in the environmental surroundings of the ksar. The aim of this study is to identify the major causes of the degradation of ksar, also to preserve ksar El-Haouita through specific operations and to improve the tourist attractiveness of ksar El-Haouita in order to promote heritage, to convert it back into sustainable Saharan tourism. Our study based in the first place; on a theoretical underpinning which contains the notions that have a relation with our theme, the problematic and the envisaged objective, then a presentation of ksar followed by a morphological analysis accompanied by identification of the problems to identify the phenomena of damage and its disfigurement. The last step is to treat an aspect for the development of ksar, this aspect is devoted to the restitution of the defensive system (doors, ramparts, ramparts of houses and towers) of the ksar, through a diagnostic and several operations like (rehabilitation and reconstruction). The aim result of this study is to show that the revaluation of the ksar is a very vast operation and proposes interventions that allow the preservation of the ksar and also to understand the elements that help the success of interventions and to put some of the parameters considered as reference elements and basic principles for the operations on the ksar and among these operations it is (the case study, which is the restitution of the defensive system of ksar El-Haouita).


2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Yingbo Ji ◽  
Siwei Chang ◽  
Yuan Qi ◽  
Yan Li ◽  
Hong Xian Li ◽  
...  

Prefabricated construction has been widely accepted as an alternative to conventional cast-in-situ construction, given its improved performance. Great efforts have also been made to develop prefabricated construction technologies in China. However, there is a lack of an appropriate pattern for evaluating its comprehensive economic merits, and reasonable mathematical models for providing a comparative analysis of conventional cast-in-situ and prefabricated building projects have yet to be developed. Therefore, the research in this paper aims to comprehensively evaluate the economic benefits of implementing prefabricated construction techniques in order to surpass the economic barrier and promote the development of prefabricated buildings in China. The comprehensive economic evaluation is formulated in terms of resource-use efficiencies, project progress, and incentive policies. An apartment building in Shanghai is selected as a case study. Construction progress is simulated on the BIM platform when the same case study is rationally transformed from the prefabricated to the conventional cast-in-situ construction technique. The results reveal that the comprehensive economic merit can reach ¥739.6/m2 when selecting the prefabricated construction process. The economic benefit brought by shortening the construction period can be regarded as the most significant contributor. Yet, the current incentive policies only contribute 7.1% of the comprehensive economic evaluation. Overall, this research contributes an assessment framework for decision-making in the technique management of building construction. The BIM-based simulation approach can greatly help investors to identify the relevant economic factors and adopt the latest incentive policies.


Author(s):  
B. Arellano ◽  
J. Roca

Abstract. The urban climate literature has highlighted the remarkable prominence of nighttime UHI phenomenon. During nighttime the UHI effects become more evident due to the greater thermal inertia of the materials used in urban fabric. It is during the night when the heat accumulated in urban materials, especially in contexts of heat waves, can generate significant health risks. The low cooling capacity of urban construction materials negatively affects the comfort and the health of urban dwellers. However, and despite the great importance of night stress due to heat, the study of night UHIs is still underdeveloped. In this context, this paper aims to determine nighttime LST contrasting Landsat's very limited nighttime images with daytime ones. The example developed refers to heat wave situations during the summer 2015. The case study is the Metropolitan Area of Barcelona (35 municipalities, 636 km2, 3.3 million inhabitants).


Heritage ◽  
2021 ◽  
Vol 4 (4) ◽  
pp. 2763-2791
Author(s):  
Osama Amer ◽  
Danila Aita ◽  
Ezzeldin k. Mohamed ◽  
Akram Torky ◽  
Ashraf Shawky

Multi-leaf stone masonry walls are a typical construction technique in architectural heritage in Egypt. The assessment, modeling, and strengthening of historic masonry walls of multi-leaf systems essentially require suitable knowledge of their construction technology, typology, geometrical characteristics, and the properties of their components. Within the current research project, a comprehensive structural survey of multiple-leaf walls of medieval historic buildings in Cairo was performed. The observation and statistical analyses allowed characterization of the transversal section of the surveyed walls, as well as examination and identification of the construction materials and techniques. The slenderness ratios of this type of wall, its blocks’ dimensions, the utilized connectivity between the inner and outer leaves, and leaves ratio were also investigated. Three construction hypotheses of multiple-leaf stone masonry walls are presented considering weak, thick, and monolithic core infill layers. The study’s objectives were to enlarge the knowledge of typology, morphology, and construction materials used in three-leaf masonry walls and provide a proper characterization as a prerequisite for determining the most suitable materials and techniques for further strengthening interventions.


2018 ◽  
pp. 60-67
Author(s):  
Henrika Pihlajaniemi ◽  
Anna Luusua ◽  
Eveliina Juntunen

This paper presents the evaluation of usersХ experiences in three intelligent lighting pilots in Finland. Two of the case studies are related to the use of intelligent lighting in different kinds of traffic areas, having emphasis on aspects of visibility, traffic and movement safety, and sense of security. The last case study presents a more complex view to the experience of intelligent lighting in smart city contexts. The evaluation methods, tailored to each pilot context, include questionnaires, an urban dashboard, in-situ interviews and observations, evaluation probes, and system data analyses. The applicability of the selected and tested methods is discussed reflecting the process and achieved results.


2013 ◽  
Vol 16 (1) ◽  
pp. 59-67

<p>The Soil Science Institute of Thessaloniki produces new digitized Soil Maps that provide a useful electronic database for the spatial representation of the soil variation within a region, based on in situ soil sampling, laboratory analyses, GIS techniques and plant nutrition mathematical models, coupled with the local land cadastre. The novelty of these studies is that local agronomists have immediate access to a wide range of soil information by clicking on a field parcel shown in this digital interface and, therefore, can suggest an appropriate treatment (e.g. liming, manure incorporation, desalination, application of proper type and quantity of fertilizer) depending on the field conditions and cultivated crops. A specific case study is presented in the current work with regards to the construction of the digitized Soil Map of the regional unit of Kastoria. The potential of this map can easily be realized by the fact that the mapping of the physicochemical properties of the soils in this region provided delineation zones for differential fertilization management. An experiment was also conducted using remote sensing techniques for the enhancement of the fertilization advisory software database, which is a component of the digitized map, and the optimization of nitrogen management in agricultural areas.</p>


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