Probability based design standards of structures

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Structural Safety Vol. 19, No. 2, pp. 219-234, 1997

ELSEWIER

PIh S0167-4730(96)00036-7

© 1997 Elsevier Science Ltd. All rights reserved Printed in The Netherlands 0167-4730/97 $17.00 + .00

Probability-based design standards of structures 1
A u g u s t f n Mrfizik *, M a r t i n K r i ~ m a
Institute of Construction and Architecture, Slovak Academy ofSciences, 842 20 Bratislava, Slovakia

Abstract The process of developing probability-based codes in the past three or four decades has been applied in rules in the deterministic form of partial reliability factors. The situation in North America and western Europe is very well known. Our paper partially reviews developments in middle and eastern Europe and presents some examples of results. Inaccordance with the paper (Ellingwood, B. R., Probability-based codified design: past accomplishment and future challenges. Structural Safety, 1994, 13, 159-176.) it advocates a preparation of international rules for the direct use of reliability methods in structural design. © 1997 Elsevier Science Ltd.

Keywords: Building codes and Standards; Design; Reliability; Theory of probability and statistics;Structural engineering

1. Introduction

Professor B. R. Ellingwood's paper [1] reviews the process of the development of probability-based codified design of structures in the past two decades in the USA and remarks that similar efforts have been made in Canada and Western Europe. This paper (and also several others, e.g. [2]) shows that the situation in countries of middle and easternEurope is not well known. Probability-based design of structures and design according to the limit states, e.g. partial reliability factors design conception, have their own history in these countries. The aim of this paper is to give a short general information about the design methods in internationally unified standardization of former Council of Mutual Economic Aid (C.M.E.A.) and more detailedinformation about standardization in former Czechoslovakia (current Slovakia and Czech Republic). The situation in other member states of the former C.M.E.A. was similar, but the authors of this paper, however, are not qualified to inform about it. This situation would be analyzed in the discussion. The main aim of the paper, however, is to support the future trend to the direct probability design.* Corresponding author. i Discussion is open until December 1997 (please submit your discussion paper to the editor, Ross B. Corotis). 219

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A. Mrdzik, M. Krigma

2. Historical review

First important pioneer works in Eastem Europe about the probability-statistical basis of the structural design elaborated in the thirties are presented in [3] and [4]. The works have continued afterWorld War II. From these, we note the intensive preparation of a structural calculation according to the limit states for the standardization in the former Soviet Union [5]. The publication of a collection of Soviet design standards for all types of structures "Building standards and rules" in 1954 was a successful result of this activity. Standardized calculation according to the limit states wasbased on the differing partial reliability factor of actions, their combinations, of material and of structural behavior conditions. An alternative calculation using partial reliability factors of the allowable stress conception was applied in 1957 in the Polish Standard of design of steel structures. Information about the development in Poland can be found in the literature [6]. Similar effortscan be seen also in other member states of the C.M.E.A. In 1961 the Steady committee of C.M.E.A. for construction has ratified a recommendation "Basic rules for calculation of building structures and foundations" as a basis for an application of the unified method. Preparatory works on the adoption of the limit states concept in the former Czechoslovakia started at the end of the fifties. The...