Relationship between Density, Compressive Stress, and Thermal Conductivity of Expanded Polystyrene Insulation
sohrab
veiseh
Head of Building Materials and Products Department, Building and Housing Research Center
author
mahnaz
mazloomisani
Researcher of Building Materials and Products Department -BHRC
author
text
article
2017
per
Abstract One of the most important factors in selecting thermal insulation products for building applications is thermal conductivity. Other factors include resistance to water vapor permeability, water absorption and mechanical properties. Determination of some of these properties is difficult and time-consuming. But determination of the density is simple, fast and cheap. If the relationships between these properties and density can be achieved by performing a lot of experiments, with measuring the density some of these properties can be estimated with good approximation. In this paper, the relationship between compressive stress and thermal conductivity with density of expanded polystyrene products (EPS) is studied. Tests for determination of density, thermal conductivity and compressive stress at 10% deformation of domestic EPS products were conducted for about 200 samples. Experimental results show that with increasing density of EPS, thermal conductivity non-linearly decreases. On the other hand, compressive stress at 10% deformation increases linearly with increase of EPS density. In this paper, the relationships between the above mentioned parameters were studied.
Building Engineering & Housing Science
مرکز تحقیقات راه، مسکن و شهرسازی
1735-8736
11
v.
4
no.
2017
1
7
https://behs.bhrc.ac.ir/article_69640_b5502746af77e91d29ec6380b1f2a20b.pdf
Non-linear Performance of the Dual System Consisting of Lightweight Steel Frame (LSF) and Moment Resisting Steel Frame
Saeid
Keramati
Civil Engineering Department, Faculty of Engineering, Persian Gulf University
author
Seyed Shaker
Hashemi
Assistant Professor, Civil Engineering Department., Persian Gulf University
author
Mohammad
Vaghefi
Civil Engineering Department, Faculty of Engineering, Persian Gulf University
author
text
article
2017
per
Abstract Lightweight Steel Frame (LSF) structures are made of cold formed steel and due to the high strength-to-weight ratio, they have been developed rapidly. They are becoming more acceptable in housing industry; especially in low rise residential buildings. Some advantages of these structures are lightness, being made of recyclable material and fast and easy installation. An important issue in the performance of these structures is their behavior in the presence of seismic loads. These structures have the ability to be combined with other lateral resistant systems like Moment Resisting Frame that operates as a dual system. LSF combined with steel frame as a dual system could reduce the construction limits like constructing stairs. In the present study, nonlinear performance of the structures has been investigated by using nonlinear static analysis. In order to achieve this, forty different 3D models of two, three, four and five story buildings have been evaluated. In other words, ten different steel-to-LSF stiffness ratios are investigated for each type. In this article, seismic parameters for each model have been determined and an optimal model is recommended for each type. Based on the results obtained in this research, in the two-story structure, Resistance is about twice and behavior factor has been increased 18%. In addition, in three-, four- and five-story buildings, this dual system has a good performance in strength and capacity and performance of ductility is increased. Moreover, structural response curves in four and five-story buildings would be more nonlinear.
Building Engineering & Housing Science
مرکز تحقیقات راه، مسکن و شهرسازی
1735-8736
11
v.
4
no.
2017
9
17
https://behs.bhrc.ac.ir/article_69649_b89477bfe2c5ec3468276aa4480955ef.pdf
Investigation and Analysis of Urban Housing Policies in Asia's East and Southeast Countries
Najma
Esmailpoor
urban planning
author
Maliheh
Zare Rodd Bazani
urban planning
author
Zhoreh
Nasrian
urban planning
author
text
article
2017
per
Abstract Providing adequate housing for the citizens, especially urban low-income groups is one of the challenges that countries are confronting with it to achieve sustainable development. Accordingly, various policies implemented to solve it. The review of experiences of different countries can provide an opportunity for housing planners and policy makers.This research done by using the descriptive, analytical and comparative method. It studied the urban housing policies and their performance in four countries in East and Southeast Asia including China, South Korea, Malaysia and Singapore mainly in the period of 1998-2011. This study has tried to present effective policies and strategies for urban housing in Iran by evaluating the results. It showed that in these countries, like Iran, urban housing problem is quantity (housing shortage) and quality (poor housing). It is because of rapid growth of urbanization and residence in marginal areas that has caused increasing in house prices. Housing policies in Asia's East and Southeast countries are divided into three general categories as follows: Increasing the grant of a property right, Build housing and Housing finance policies by government to provide economical housing for low-income groups. In these countries the policy of providing housing by government evolved into Privatization. The economic growth in these countries had Positive impact on the performance of the housing sector, and housing programs are an integral part of their local and national economic policies and this is the cause of their relative success. Also, the proposed policy package that is based on the Iran's housing vision 1404 has been presented.
Building Engineering & Housing Science
مرکز تحقیقات راه، مسکن و شهرسازی
1735-8736
11
v.
4
no.
2017
19
33
https://behs.bhrc.ac.ir/article_69652_36a6b2c4925ee72e4d760e5881883f0d.pdf
Performance of Wet Cooling Towers under Various Climates in Iran
Maryam
Karami
Member of scientific board of Kharazmi University
author
Shahram
Delfani
Mechanical and electrical Installations department- BHRC- Tehran-Iran
author
text
article
2017
per
Abstract In this paper, performance of the cooling tower is studied for different climatic regions of Iran. First, a complete mathematical model of cooling tower which contains spray, fill and rain zones is developed. The results are validated by experimental measurements. Then, the important characteristics of the cooling towers consist of the Range and the Approach is obtained for each climatic area. It is found that these characteristics strongly dependent on outdoor conditions. Due to low humidity and high dry-bulb temperature of air in central areas of Iran, Range value is significantly increased. In contrast, the higher the humidity, the lower Range is obtained (along Caspian Sea, Persian Gulf and OmanSea). In such areas, wet cooling towers cannot lonely respond to cooling requirement and based on air wet bulb temperature value can be accompanied with an appropriate auxiliary system such as indirect evaporative cooling (IEC).
Building Engineering & Housing Science
مرکز تحقیقات راه، مسکن و شهرسازی
1735-8736
11
v.
4
no.
2017
35
41
https://behs.bhrc.ac.ir/article_69672_aeb3f9ffb207a9bf43b2117bfaece986.pdf
Design and Installation of Rapid Response System for Tehran City
Hossein
Mirzaei Alavijeh
IRAN STRONG mOTION
author
Esmaeil
Farzanegan
Researcher
author
Fereydoon
Sinaeian
Researcher
author
Hossein
Abdollahi Tichi
author
text
article
2017
per
Abstract The Greater Tehran Area is located at the foot slope area of the Alborz Mountains, which form part of the Alpine-Himalayan Orogenic Zone. The urban area of Tehran has been developed on alluvial layers accumulated on hard rock through complex geological formations. Seismologists believe that a strong earthquake will strike Tehran in near future, because the city has not experienced a disastrous earthquake since 1830. Fast growth of population and urbanization in previous decades due to immigration, lack of strong regulations for urban development and existence of several active faults around the city cause the vulnerability of Tehran against the moderate to large earthquakes. A modern strong motion network in Tehran plays an important role in making a rapid response to the incoming earthquakes. This network is able to improve the conditions for determination of magnitude, location and engineering parameters of the regional earthquakes. With the aims of acquiring and monitoring of strong motion data, development of empirical strong ground motion data base, improvement in microzonation, and obtaining effective information for estimation of ground shaking and damage, a strong motion network including 20 stations has been installed in Tehran metropolitan area. Establishment of this network has been done by Iranian Strong Motion Network (ISMN) department of Building and Housing Research Center (BHRC) in frame of a pilot project called “design, installing and operating of earthquake rapid response system for 20 strong motion stations in Tehran’’.
Building Engineering & Housing Science
مرکز تحقیقات راه، مسکن و شهرسازی
1735-8736
11
v.
4
no.
2017
43
48
https://behs.bhrc.ac.ir/article_69678_6c8e61235d3a17456a0742e72ec0ced1.pdf
Iranian Architecture and Symbolism in Iranian Gardens, Case Study: Eram Garden
FAHIMEH
YARI
BHRC
author
RAZIEH
Hoorshenas
TMU
author
text
article
2017
per
Abstract Thinking is a part of Iran’s cultural heritage, which has manifested more than any other part of the architecture in the design of Persian garden. A concept that stems from religious beliefs, national myths, and human experiences of the peoples of this land. The paper studies the analysis of concepts in the mysteries and manifestations of Persian garden. Then, based on the concepts explained in the article’s theoretical framework, the case study of Eram Garden of Shiraz is analyzed. Studies conducted in this research show that the spiritual concepts and mental beliefs of Iranians are well represented in the form of symbolic crypts in the Persian Eram gardens, and the analyzed sample of Eram Garden of Shiraz is a proof of this claim. Thinking about the mysteries of the process of construction of Persian garden has begun, stretching in the formation of elements of artifact and natural elements. The design of walls and fences, motor routes, hierarchies and platforms, decorative elements, pavilions, and artificial constructions and natural elements can all be interpreted on the basis of this view. As if the theoretical foundations and the decorative elements of garden designing were formed on the basis of a cryptic and contemplative approach. Cryptic thinking is a part of the concept of design and is interpreted along with it so that the Persian garden can be considered as an objective-subjective experience of manifestations of cultural crypts.
Building Engineering & Housing Science
مرکز تحقیقات راه، مسکن و شهرسازی
1735-8736
11
v.
4
no.
2017
49
55
https://behs.bhrc.ac.ir/article_69693_4ac166bea8c9f048ea9adc3881a1bbf1.pdf
Studying Variety of Intelligent Control System Techniques in Hospitals for Optimization of Energy Consumption
hamed
rashidi aghdam
Road, Housing, and Urban Development Research Center
author
leila
yarmohammadi
Commissioning organization for state & public Building Installation
author
seid hossein
malakooti
Road, Housing, and Urban Development Research Center,
author
text
article
2017
per
Abstract In this paper, we studied a variety of intelligent control systems in hospitals and typically simulated a hospital to choose an optimum method. The purpose of this paper is research on variety of hospital areas which need intelligent control system and identifying method, equipment and proper protocols for monitoring and being intelligent based on EN 15232 Standard. According to the vital roles of factors such as accuracy, fast and reliability of Therapeutic area and according to Vulnerable Therapeutic system to human fault that intelligent management and automation of this places has important roles for supplying security and relaxing patient, use of natural light in this areas, to economize on energy consumption and proper control of temperature, humidity and quality of air, also this system manage to money, staff, patient and equipment. The results of simulation show that consumption of energy was reduced about 20 percent which has significant impact on current and future cost of electrical system.
Building Engineering & Housing Science
مرکز تحقیقات راه، مسکن و شهرسازی
1735-8736
11
v.
4
no.
2017
57
63
https://behs.bhrc.ac.ir/article_69696_869887c1e8d9b58b7d5eb82f8b138331.pdf