• Title/Summary/Keyword: codes provisions

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A Multiple Database-Enabled Design Module with Embedded Features of International Codes and Standards

  • Kwon, Dae Kun;Kareem, Ahsan
    • International Journal of High-Rise Buildings
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    • v.2 no.3
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    • pp.257-269
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    • 2013
  • This study presents the development of an advanced multiple database-enabled design module for high-rise buildings (DEDM-HR), which seamlessly pools databases of multiple high frequency base balance measurements from geographically dispersed locations and merges them together to expand the number of available building configurations for the preliminary design. This feature offers a new direction for the research and professional communities that can be utilized to efficiently pool multiple databases therefore expanding the capability of an individual database and improving the reliability of design estimates. This is demonstrated, in this study, by the unprecedented fusion of two major established databases, which facilitates interoperability. The DEDM-HR employs a cyberbased on-line framework designed with user-friendly/intuitive web interfaces for the convenient estimation of wind-induced responses in the alongwind, acrosswind and torsional directions with minimal user input. In addition, the DEDM-HR embeds a novel feature that allows the use of wind characteristics defined in a code/standard to be used in conjunction with the database. This supplements the provisions of a specific code/standard as in many cases guidance on the acrosswind and torsional response estimates is lacking. Through an example, results from several international codes and standards and the DEDM-HR with the embedded features are compared. This provision enhances the scope of the DEDM-HR in providing an alternative design tool with nested general provisions of various international codes and standards.

Moment redistribution of RC continuous beams: Re-examination of code provisions

  • Da Luo;Zhongwen Zhang;Bing Li
    • Structural Engineering and Mechanics
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    • v.85 no.5
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    • pp.679-691
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    • 2023
  • Many codes allow designers to use the bending moment diagram computed by elastic analysis and modify it by a certain amount of moment redistribution (MR) to account for plastic behaviour of continuous beams. However, several researchers indicated that the MR at the ultimate limit state (𝛽u) for some beams deviate significantly from the specified values of various codes. This paper examines the applicability of the provisions on 𝛽u in ACI 318-19 and Eurocode 2 through numerical investigations and comprehensively explores the influencing factors. The results show that some parameters not considered in those codes influence 𝛽u to a certain extent, where the ratio of tensile reinforcement ratio at intermediate support to tensile reinforcement ratio at midspan (𝜌s1/𝜌s2) and load type are crucial parameters to consider. The specific combination of these two parameters may make the codes overestimate or significantly underestimate the 𝛽u. On the other hand, the yield state of both critical sections is found to have an important influence on the influence degree of each parameter on 𝛽u. The yield conditions are investigated, and an empirical judgment equation is proposed. In addition, the influence laws of the critical parameters on 𝛽u have been further proved by theoretical derivation. Finally, due to 𝜀t is found to have a better linear correlation with 𝛽u than xu/d, equations as a function of 𝜀t for predicting the 𝛽u of continuous beams under the two loads are proposed, respectively.

Seismic design of beam-column joints in RC moment resisting frames - Review of codes

  • Uma, S.R.;Jain, Sudhir K.
    • Structural Engineering and Mechanics
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    • v.23 no.5
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    • pp.579-597
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    • 2006
  • The behaviour of reinforced concrete moment resisting frame structures in recent earthquakes all over the world has highlighted the consequences of poor performance of beam column joints. Large amount of research carried out to understand the complex mechanisms and safe behaviour of beam column joints has gone into code recommendations. This paper presents critical review of recommendations of well established codes regarding design and detailing aspects of beam column joints. The codes of practice considered are ACI 318M-02, NZS 3101: Part 1:1995 and the Eurocode 8 of EN 1998-1:2003. All three codes aim to satisfy the bond and shear requirements within the joint. It is observed that ACI 318M-02 requires smaller column depth as compared to the other two codes based on the anchorage conditions. NZS 3101:1995 and EN 1998-1:2003 consider the shear stress level to obtain the required stirrup reinforcement whereas ACI 318M-02 provides stirrup reinforcement to retain the axial load capacity of column by confinement. Significant factors influencing the design of beam-column joints are identified and the effect of their variations on design parameters is compared. The variation in the requirements of shear reinforcement is substantial among the three codes.

Comparison of Fatigue Provisions in Various Codes and Standards -Part 1: Basic Design S-N Curves of Non-Tubular Steel Members

  • Im, Sungwoo;Choung, Joonmo
    • Journal of Ocean Engineering and Technology
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    • v.35 no.2
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    • pp.161-171
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    • 2021
  • For the fatigue design of offshore structures, it is essential to understand and use the S-N curves specified in various industry standards and codes. This study compared the characteristics of the S-N curves for five major codes. The codes reviewed in this paper were DNV Classification Rules (DNV GL, 2016), ABS Classification Rules (ABS, 2003), British Standards (BSI, 2015), International Welding Association Standards (IIW, 2008), and European Standards (BSI, 2005). Types of stress, such as nominal stress, hot-spot stress, and effective notch stress, were analyzed according to the code. The basic shape of the S-N curve for each code was analyzed. A review of the survival probability of the basic design S-N curve for each code was performed. Finally, the impact on the conservatism of the design was analyzed by comparing the S-N curves of three grades D, E, and F by the five codes. The results presented in this paper are considered to be a good guideline for the fatigue design of offshore structures because the S-N curves of the five most-used codes were analyzed in depth.

Investigation of shear lag effect on tension members fillet-welded connections consisting of single and double channel sections

  • Barkhori, Moien;Maleki, Shervin;Mirtaheri, Masoud;Nazeryan, Meissam;Kolbadi, S.Mahdi S.
    • Structural Engineering and Mechanics
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    • v.74 no.3
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    • pp.445-455
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    • 2020
  • Shear lag phenomenon has long been taken into consideration in various structural codes; however, the AISC provisions have not proposed any specific equation to calculate the shear lag ratio in some cases such as fillet-welded connections of front-to-front double channel sections. Moreover, those equations and formulas proposed by structural codes are based on the studies that were conducted on riveted and bolted connections, and can be applied to single channel sections whilst using them for fillet-welded double channels would be extremely conservative due to the symmetrical shape and the fact that bending moments will not develop in the gusset plate, resulting in less stress concentration. Numerical models are used in the present study to focus on parametric investigation of the shear lag effect on fillet-welded tension connection of double channel section to a gusset plate. The connection length, the eccentricity of axial load, the free length and the thickness of gusset plate are considered as the key factors in this study. The results are then compared to the estimates driven from the AISC-LRFD provisions and alternative equations are proposed.

Comparing calculation methods of storey stiffness to control provision of soft storey in seismic codes

  • Tabeshpour, Mohammad Reza;Noorifard, Azadeh
    • Earthquakes and Structures
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    • v.11 no.1
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    • pp.1-23
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    • 2016
  • Numerous buildings have been damaged or destroyed in previous earthquakes by developing soft storey. Almost all the seismic codes have provisions to prevent soft storey in structures, most of them have recommended the ratio of stiffness between adjacent storeys, but none of them has proposed the method to calculate the storey stiffness. On the other hand a great number of previous researches on stiffness have been focused on approximate methods and accurate methods by using analytical softwares have been almost neglected. In this study, six accurate methods for calculating the storey stiffness have been studied on 246 two-bay reinforced concrete frames. It is shown with the results of the statistical study and structural analysis that method 3 in which there is no modification of the original model and the forces with triangular distribution similar to seismic forces are applied to the center of mass of all storeys has acceptable accuracy and desirable efficiency for designing and controlling structures.

Earthquake induced torsion in buildings: critical review and state of the art

  • Anagnostopoulos, S.A.;Kyrkos, M.T.;Stathopoulos, K.G.
    • Earthquakes and Structures
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    • v.8 no.2
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    • pp.305-377
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    • 2015
  • The problem of earthquake induced torsion in buildings is quite old and although it has received a lot of attention in the past several decades, it is still open. This is evident not only from the variability of the pertinent provisions in various modern codes but also from conflicting results debated in the literature. Most of the conducted research on this problem has been based on very simplified, highly idealized models of eccentric one-story systems, with single or double eccentricity and with load bearing elements of the shear beam type, sized only for earthquake action. Initially, elastic models were used but were gradually replaced by inelastic models, since building response under design level earthquakes is expected to be inelastic. Code provisions till today have been based mostly on results from one-story inelastic models or on results from elastic multistory idealizations. In the past decade, however, more accurate multi story inelastic building response has been studied using the well-known and far more accurate plastic hinge model for flexural members. On the basis of such research some interesting conclusions have been drawn, revising older views about the inelastic response of buildings based on one-story simplified model results. The present paper traces these developments and presents new findings that can explain long lasting controversies in this area and at the same time may raise questions about the adequacy of code provisions based on results from questionable models. To organize this review better it was necessary to group the various publications into a number of subtopics and within each subtopic to separate them into smaller groups according to the basic assumptions and/or limitations used. Capacity assessment of irregular buildings and new technologies to control torsional motion have also been included.

Study of wind tunnel test results of high-rise buildings compared to different design codes

  • Badri, Abdulmonem A.;Hussein, Manar M.;Attia, Walid A.
    • Wind and Structures
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    • v.20 no.5
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    • pp.623-642
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    • 2015
  • Several international codes have been developed for evaluating wind loads on structures; however, the wind structure interaction could not be accurately captured by these codes due to the gusty nature of wind and the dynamic behavior of structures. Therefore, the alternative wind tunnel testing was introduced. In this study, an introduction to the available approaches for wind load calculations for tall buildings was presented. Then, a comparative study between different codes: the Egyptian code, ECP 201-08, ASCE 7-05, BS 6399-2, and wind tunnel test results was conducted. An investigation has been carried out on two case studies tall buildings located within the Arabian Gulf region. Numerical models using (ETABS) software were produced to obtain the relation between codes analytical values and wind tunnel experimental test results for wind loads in the along and across wind directions. Results for the main structural responses including stories forces, shears, overturning moments, lateral displacements, and drifts were presented graphically in order to give clear comparison between the studied methods. The conclusions and recommendations for future works obtained from this research are finally presented to help improving Egyptian code provisions and show limitations for different cases.

A Study on Using the Interior Finishing Material using Regulation at Multiple-using Businesses (다중이용업소 실내마감재료 사용기준에 관한 연구)

  • Kim, Yong-Sung;Cho, Sung-O
    • Korean Institute of Interior Design Journal
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    • v.22 no.5
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    • pp.216-224
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    • 2013
  • There are the relevant provisions that apply to building regulations about the Building codes, Fire Protection laws, and more Multi-using interior finish materials businesses etc. The differences between these regulations are as follows: The Building codes is defined the main use of the building according to facilities to used to set the scale by the use of the floor space, On the other hand, Fire Protection laws are the basic purpose and the act of using the architectural space(or sales) by separating object by fire. And Multiple-using Businesses Facilities consist of two regulations engaged in the kind of law and the size of the floor area. One building can not be based on operating facilities and together in Multiple use businesses Law. As such, the Buildings are applied to the Building codes, Fire Protection laws, such as Multi-using Businesses Facilities interior construction industry due to the structural differences in the position of the designer feeling a lot of difficulties and confusion. The Multi-use businesses Facilities engage in the kind of law, the size of the floor area and seating capacity. These can not be based on operating facilities, and consists of two regulations together in one building. This study is purposed to help improving the finish of the interior architecture that is related to the Building code regulations, Fire Protection laws, Multi-using Facilities interior finishing material relevant with the provisions from the law through analyze the case of developed countries, and the current Multiple use Businesses Facilities research range from the law of multiple-using facilities, interior finishing, interior architecture for supervision reasonably and compensation for the interior design. So, Result is as follows: First, interior decorations can be separated the fixed material and the moveable things. second, It should be included multi-using Business though small size business space at the basement floor. third, It should be established statute law that design and construction responsibility. forth, re-testing fire resist performance after some period. and finally, it need to mitigate regulation where be installed sprinkler.

Comparison of the seismic performance of existing RC buildings designed to different codes

  • Zeris, Christos A.;Repapis, Constantinos C.
    • Earthquakes and Structures
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    • v.14 no.6
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    • pp.505-523
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    • 2018
  • Static pushover analyses of typical existing reinforced concrete frames, designed according to the previous generations of design codes in Greece, have established these structures' inelastic characteristics, namely overstrength, global ductility capacity and available behaviour factor q, under planar response. These were compared with the corresponding demands at the collapse limit state target performance point. The building stock considered accounted for the typical variability, among different generations of constructed buildings in Greece, in the form, the seismic design code in effect and the material characteristics. These static pushover analyses are extended, in the present study, in the time history domain. Consequently, the static analysis predictions are compared with Incremental Dynamic Analysis results herein, using a large number of spectrum compatible recorded base excitations of recent destructive earthquakes in Greece and abroad, following, for comparison, similar conventional limiting failure criteria as before. It is shown that the buildings constructed in the 70s exhibit the least desirable behaviour, followed by the buildings constructed in the 60s. As the seismic codes evolved, there is a notable improvement for buildings of the 80s, when the seismic code introduced end member confinement and the requirement for a joint capacity criterion. Finally, buildings of the 90s, designed to modern codes exhibit an exceptionally good performance, as expected by the compliance of this code to currently enforced seismic provisions worldwide.