Engineering Mechanics

Proceedings Vol. 13 (2007)

ENGINEERING MECHANICS 2007

Copyright © 2007 Institute of Thermomechanics, Academy of Sciences of the Czech Republic, v.v.i., Prague

 

Koudelka P.
pages 125 - +6p., full text

Now, the translation in Czech and National Annex of EC7-1 (EUROCODE 7 - Geotechnical design, Part 1: General rules) are made. The principal difference exists between inputs according to EC7-1 and inputs according to the Czech basic standard ČSN 73 0031 “Structural reliability – Basic requirements for design”. In general, the input difference leads to too conservative (ineffective) designs accordin to EC7-1 and more effective (more optimistic) designs according to ČSN. A comparative numerical analysis of the both design procedures appears useful. The paper deals with a similarity solution of bearing capacity of bored piles according to ČSN 73 1002 “Pile foundations” (1987). The solution should provide a part of the comparing analysis base for a simpler analysing. 1 Introduction The theoretical base of the EC7-1 Limit State Design is very dissimilar, more conservative, than the one of the Czech basic standard ČSN 73 0031 (Structural reliability - Basic requirements for design) which is proved by the long-term successful practice. Mostly, this fact is due to the different definitions of material inputs, i.e. characteristic/standard and design values. While the EC7-1 defines for characteristic values the probability of 95% the standard values according to ČSN 73 0031 are defined like the average (probability of 50%). The definitions of design values according to the both regulations are the same but, of course, due to different characteristic/standard value definitions the material partial factors differ. Due to it the analyses of slopes, shallow foundations and earth pressure concept have been carried out and the analysis pile design appears necessary too. The analysis need a wide concept for numerical comparison. The suitable way for it is a similarity solution of the design procedure and this is the object of the Paper. Czech standard ČSN 73 1002 “Pile foundations” (1987 in force) does not involve a numerical design procedure but directly the tables of the design bearing capacity of different pile types. The standard numerical design procedure for piles is presented in ČSN 73 1004 "Drilled piles" (1981) which is not yet in force. However, the last mentioned standard procedure is only the Czech one for numerical design and the Paper applies it. The Paper deals with a similarity solution of bearing capacity of shallow foundations according to ČSN 73 1004 with a number of parameters. An easier approach of the problem solution appears theory of ∗

Text and facts may be copied and used freely, but credit should be given to these Proceedings.

All papers were reviewed by members of the scientific committee.