Közúti és vasúti hidász almanach 2007 (Lánchíd füzetek 8., 2008)

HIDÁSZ ALMANACH 2007 ANNO - 2007 g Bibliográfia properties of FRP reinforcing bars is presented, with special emphasis on durability aspects. For each of the typical ultimate and serviceability limit states, the basic mechanical model is given, followed by different design models according to existing codes or design guidelines. Composite FRP materials are still relatively new in construction and most engineers are unfamiliar with their properties and characteristics. The second chapter of this bulletin therefore aims to provide practising engineers with the necessary background knowledge in this field, and also presents typical products currently available in the international market. The third chapter deals with the issue of durability and identifies the parameters that can lead to deterioration, which is necessary information when addressing design issues. A series of parameters is used to identify the allowable stress in the FRP after exposure for a specified period of time in a specific environment. The bulletin covers the issues of Ultimate Limit States (primarily dealing with flexural design), Serviceability Limit States (dealing with deflections and cracking), Shear and Punching Shear and Bond and Tension Stiffening. It provides not only the state-of-the-art but also in many cases ideas for the next generation of design guidelines. The final chapter deals with the fundamental issue of design philosophy. The use of these new materials as concrete reinforcement has forced researchers to re-think many of the fundamental principles used until now in RC design. The bulletin ends with a discussion of a possible new framework for developing partial safety factors to ensure specific safety levels that will be flexible enough to cope with new materials. (

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) 160 pages, in English, 120 CHF. Treatment of imperfections in precast structural elements -fib bulletin 41 A Nemzetközi Betonszövetség (fib) 1999-ben tematikus szakmai közlöny sorozatot indított. Az alábbiakban megadjuk a kötet összefoglalóját. fib Bulletin 41 addresses the most common types of imperfections encountered during the manufacture, stacking, transport and erection of precast concrete structural elements, and suggests a number of possible remedial actions. The remedial actions depend on the severity of the imperfection, the feasibility of repair and the consequences on the intended use of the concrete member. Imperfections in concrete structures are impossible to avoid and can range from minor surface blemishes to major structural defects. Because many imperfections are at the limits of specified quality deviations, or are not included in the acceptance criteria, the problem is more complex than a decision between rejection or acceptance. This document deals with precast concrete elements that do not meet the quality as intended in the design. It compares imperfections in quality to the specified requirements so that the effect of the imperfection can be evaluated. 138