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Reliability Index of Tall Buildings in Earthquake Zones  [PDF]
Mohammed S. Al-Ansari
Open Journal of Earthquake Research (OJER) , 2013, DOI: 10.4236/ojer.2013.23005
Abstract:

The paper develops a reliability index approach to assess the reliability of tall buildings subjected to earthquake loading. The reliability index β model measures the level of reliability of tall buildings in earthquake zones based on their response to earthquake loading and according to their design code. The reliability index model is flexible and can be used for: 1) all types of concrete and steel buildings and 2) all local and international codes of design. Each design code has its unique reliability index β as a magnitude and the interaction chart corresponding to it. The interaction chart is a very useful tool in determining the building drift for the desired level of reliability during the preliminary design of the building members. The assessments obtained using the reliability index approach of simulated, tested, and actual buildings in earthquake zones were acceptable as indicators of the buildings reliability.

Shell Roof of Tall Buildings in Earthquake Zones  [PDF]
Mohammed Salem Al-Ansari, Muhammad Shekaib Afzal
Open Journal of Earthquake Research (OJER) , 2019, DOI: 10.4236/ojer.2019.84013
Abstract: This paper studies and analyzes tall buildings with shell and flat roof responses designed for gravity and earthquake loads in different zones having different soil profiles. These tall buildings having two different heights and different configurations are simulated with different load combinations. The responses of the simulated structural models with flat and shell roofs are studied and analyzed. These responses draw recommendations and guidelines for preliminary design of structurally efficient and reliable tall buildings with shell roof in earthquake zones. Five different earthquake zone factors (Z1 - Z5) along with the five different soil profiles (S1 - S5) are selected in this study. The non-linear dynamic response of buildings was obtained using three simulated models of buildings; square/rectangular, circular, and tube-shaped building. Total of 12 building models, four under each category, are analyzed using the finite element software (STAAD pro) subjected to the gravity as well as earthquake loading defined by UBC and IBC codes. Each building model is analyzed with two different story heights; which are 120 meters for 30 stories and 72 meters for 18 stories respectively. Horizontal and vertical displacement comparison is made among the flat roof and shell roof building for 32 and 18 stories building satisfying the ACI code of design requirement and drift index of 1/500 (0.002). The results showed that the drift index value for all the studied buildings is close to 0.002. All the maximum horizontal and vertical deflections occur under the earthquake zone-5 (0.40 gravitational acceleration) with soil profile-5 (Soft soil). The shell roof slab with less thickness than the flat roof slab did satisfy the horizontal and vertical deflection limits, therefore, it is more economical than the flat roof slab.
Influence of building envelope thermal protection on heat loss value in the building (rus)
Vatin N.I.,Nemova D.V.,Rymkevich P.P.,Gorshkov A.S.
Magazine of Civil Engineering , 2012,
Abstract: The research presents the calculations for the heat losses through the envelope of the apartment building. The calculations are provided for different levels of insulation of enclosing structures (i.e. wall, windows, roof etc) according to three normative documents: Set of rules 50.13330.2012 (rus), Construction Norms and Regulations 23-02-2003 (rus) and National Building Code of Finland, Part D3 (fin). The impact of level of thermal protection of external enclosure structures on the values of heat losses, the operating costs and the costs of fuel and energy resources during the heating period (for 10, 30 and 50 years of upkeep of buildings) on the example of the one habitable apartment building is analyzed. Calculation of payback periods of the energy saving actions directed on increase of level of thermal protection of external enclosure structures of buildings is given. Economic efficiency of investments in energy saving measures is analyzed.
Enhancing Life Safety Provisions in Fire Zones of Buildings
Lilly grace murali P.,,M. M. Vijayalakshmi
International Journal of Engineering Research , 2014,
Abstract: ABSTRACT: Fire accident in building is a threatening one now a day. These accidents create heavy lives and property losses. To find the reasons, frequency and giving protection to all type of buildings became challenges to the professionals. Fire causes different types of losses but in this paper the lives losses and its passive remedy given importance. The statistical data of twelve years from 2000 to 2012 lives losses has been taken as survey, it is analyzed and the results are discussed. This analysis results directs two case studies which are took placed in Tamil Nadu and considered as major lives losses fire accidents. These case studies concluded with solutions. Fire and lives safety aspects in term of escapes routes design recommendations are given here to improve the lives safety in buildings for future.
On the Establishment of Climatic Zones in Europe with Regard to the Energy Performance of Buildings  [PDF]
Katerina Tsikaloudaki,Kostas Laskos,Dimitrios Bikas
Energies , 2012, DOI: 10.3390/en5010032
Abstract: Nowadays, subjects such as eco-design requirements, product rating or code compliance with regard to energy efficiency are expanding towards a pan-European level. This leads to the necessity of defining zones within the European region, which share common climatic characteristics and will further facilitate the quick estimation of building energy performance. Towards this direction stands the current paper; it presents an approach for defining climatic zones in Europe on the basis of the amount of heating and cooling degree days. It is applied for the climate classification of selected European cities and is compared with the conventional scheme based solely on heating degree days. Since the approach is orientated mainly towards the assessment of building energy performance, its outcomes are evaluated with regard to the actual heating and cooling energy needs of a reference building unit with office use located in representative cities of the proposed climatic zones and facing the four cardinal orientations. The classification of climatic zones on the basis of both heating and cooling degree days leads to more realistic results, since nowadays cooling needs form a substantial part of the energy balance of the building, especially in the Mediterranean regions.
Estimation of masonry mortars strength during stone buildings investigation (rus)  [PDF]
Orlovich R.B.,Derkach V.N.
Magazine of Civil Engineering , 2011,
Abstract: In this article the analysis of estimation methods of the masonry mortars strength applied in Russia and other countries during stone buildings and constructions investigation was carried out. Advantages and disadvantages of these methods are considered.The new technique of masonry mortars strength estimation is offered. It is based on trials of bored from a masonry body cylindrical samples. It is pointed, that this method is the most universal and informative from all methods considered in this article. The offered testing procedure allows to gain not only a compression strength, but also a shearing strength along horizontal masonry seams. Results of experimental researches of masonry mortars compression strength executed on various techniques are presented.
The formula of double-glazed window in high-rise buildings (rus)  [PDF]
Kurenkova A.Yu.,Kuzmenko A.V.,Kurenkova O.M.
Magazine of Civil Engineering , 2011,
Abstract: The purpose of this article is to adapt the method of glass unit calculating taking into account shortterm loads during installation and construction loads occurring during the operation of the building. Considering the fact that nowadays Russian standards are going to be harmonized with European, in this methodology the rules applicable in the European Union and adapted to Russian climate has been used.The offered technique allows to take into account in the calculations not only the glass unit wind load, but also climatic and temperature effects for site-specific installation of window unit. The calculations indicate the necessity of using this technique, especially for high-rise buildings. The calculation allows to receive the most accurate formula for the glass, to calculate not only the thickness of the external and internal glass pack, but also the distance between glasses, which had not previously been practiced. This article shows an example of the glass pack calculation for a specific building, which height is 81 m.
Testing of calculation method of the enclosing structures temperature-humidity conditions on the results of indoor climate in-situ measurements
Korniyenko S. V.
Magazine of Civil Engineering , 2012,
Abstract: The problem of energy expenses decreasing and buildings energy efficiency growth is closely connected with necessity of heat and mass exchange processes research, forecasting of the enclosing structures temperature-humidity conditions and increasing of heat engineering calculations reliability.In this article the results of indoor climate parameters in-situ measurements are used for testing the method of temperature-humidity conditions calculation in three-dimensional areas of enclosing structures developed by the author. Testing of this method confirms its veracity that allows to use the specified method in design practice.
Minimum Enclosing Polytope in High Dimensions  [PDF]
Rina Panigrahy
Computer Science , 2004,
Abstract: We study the problem of covering a given set of $n$ points in a high, $d$-dimensional space by the minimum enclosing polytope of a given arbitrary shape. We present algorithms that work for a large family of shapes, provided either only translations and no rotations are allowed, or only rotation about a fixed point is allowed; that is, one is allowed to only scale and translate a given shape, or scale and rotate the shape around a fixed point. Our algorithms start with a polytope guessed to be of optimal size and iteratively moves it based on a greedy principle: simply move the current polytope directly towards any outside point till it touches the surface. For computing the minimum enclosing ball, this gives a simple greedy algorithm with running time $O(nd/\eps)$ producing a ball of radius $1+\eps$ times the optimal. This simple principle generalizes to arbitrary convex shape when only translations are allowed, requiring at most $O(1/\eps^2)$ iterations. Our algorithm implies that {\em core-sets} of size $O(1/\eps^2)$ exist not only for minimum enclosing ball but also for any convex shape with a fixed orientation. A {\em Core-Set} is a small subset of $poly(1/\eps)$ points whose minimum enclosing polytope is almost as large as that of the original points. Although we are unable to combine our techniques for translations and rotations for general shapes, for the min-cylinder problem, we give an algorithm similar to the one in \cite{HV03}, but with an improved running time of $2^{O(\frac{1}{\eps^2}\log \frac{1}{\eps})} nd$.
Volume-Enclosing Surface Extraction  [PDF]
B. R. Schlei
Computer Science , 2010, DOI: 10.1016/j.cag.2011.12.008
Abstract: In this paper we present a new method, which allows for the construction of triangular isosurfaces from three-dimensional data sets, such as 3D image data and/or numerical simulation data that are based on regularly shaped, cubic lattices. This novel volume-enclosing surface extraction technique, which has been named VESTA, can produce up to six different results due to the nature of the discretized 3D space under consideration. VESTA is neither template-based nor it is necessarily required to operate on 2x2x2 voxel cell neighborhoods only. The surface tiles are determined with a very fast and robust construction technique while potential ambiguities are detected and resolved. Here, we provide an in-depth comparison between VESTA and various versions of the well-known and very popular Marching Cubes algorithm for the very first time. In an application section, we demonstrate the extraction of VESTA isosurfaces for various data sets ranging from computer tomographic scan data to simulation data of relativistic hydrodynamic fireball expansions.
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