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Some standards for the design of concrete structures (e.g. EC2 and the original ČSN 73 1201-86) allow a structure to be designed by several methods. This contribution documents the fact that even if a structure does not comply with the partial reliability factor method, according to EC2, it can satisfy the conditions during the application of the fully probabilistic approach when using the same standard. From an example of the reliability of a prestressed spun concrete pole designed by the partial factor method and fully probabilistic approach according to the Eurocode it is evident that an expert should apply a more precise (though unfortunately more complicated) method in the limiting cases. The Monte Carlo method, modified by the Latin Hypercube Sampling (LHS) method, has been used for the calculation of reliability. Ultimate and serviceability limit states were checked for the partial factor method and fully probabilistic design. As a result of fully probabilistic design it is possible to obtain a more efficient design for a structure.Keywords: probabilistic design, partial reliability factor, concrete structures design.Algúnos estándares para el diseño de estructuras de hormigón (p. ej. EC2 y la original ČSN 73 1201-86) permiten que las estructuras sean diseñadas utilizando diferentes métodos. Esta contribución trata casos en los cuales una estructura dada que incluso no obedece el método de índice de confiabilidad parcial, de acuerdo a EC2, puede satisfacer las condiciones requeridas durante la aplicación del método probabilístico cuando se usa el mismo estándar. Tomado de una muestra de la confiabilidad de un hormigón pretensado hilado diseňado con la ayuda del método de índice parcial y por el método probabilistico de acuerdo al código Euro (Eurocode) es evidente que un experto debe aplicar un método más preciso (pero desafortunadamente más complicado) en los casos limitantes. El método Monte Carlo modificado por el método (LHS) Latin Hybercube Sampling ha sido utilizado para efectuar el cálculo de confiabilidad. Los límites extremos y de utilidad fueron comprobados para el método de índice parcial y diseño probabilístico completo. Como resultado del método de diseño probabilístico es posible obtener un diseño más eficiente para una estructura.Palavras-chave: diseño probabilístico, índice de confiabilidad parcial, diseño de estructuras de hormigón. Technology, Faculty of Civil Engineering, zlamal.m@fce.vutbr.cz, Veveří 95, 602 00 Brno, Czech Republic Received: 26 Nov 2010 • Accepted: 27 Mar 2011 • Available Online: 10 Jun 2011 Abstract Resumo Fully probabilistic design -the way for optimising of concrete structures

In cases when two concrete parts are cast against in different times are not connected by dowels, main contributors to the resistance are cohesion and friction. Shear resistance of the interface is highly dependent on surface treatment and its roughness. In this paper, besides the review of available methods of surface roughness determination, the optical profilometry will be introduced and described. Optical profilometry represents non-contact and non-destructive method for characterizing surface topography. Furthermore, results obtained by abovementioned method will be compared with Sand Patch Test, in order to determine its usability and limitations.

New type of fiber reinforced polymer (FRP) reinforcement has been developed in previous years at Brno University of Technology, which can be used for reinforcing, strengthening and prestressing of concrete structures. The main advantage of FRP reinforcement is resistibility against aggressive environment and thus the possibility to use thinner concrete cover. High durability and resistibility are demanded from modern constructions. Some of the influences cover the effects of fire exposure or high temperature in general. Hence the next part of the research is focused on resistibility of FRP reinforced structures under effects of fire. The paper deals with experiments oriented to observing the behaviour of prestressed and non-prestressed FRPRC panels subjected to fire effects as well as behaviour of FRP reinforcement itself. Results of experiments proved resistibility of FRP reinforced panels to fire effects. They also demonstrate the importance of understanding the behaviour of composite reinforcing bars alone and their behaviour along the anchoring zone in concrete members exposed to fire. A sufficient anchorage length (enabling the transfer of load from the reinforcement into the concrete) turned out to be a key feature enabling a structure to withstand over much longer time periods and even under surprisingly high temperatures.

The primary aim of this article is to present design approaches for calculating the additional strengthening of masonry arches with the use of the Strut-and-Tie model and applicable standards and their comparison to the experiments. Experiments have proven the functionality of the described method of strengthening by additional inserted non-prestressed reinforcement from the face of the vault. The presented method is one of the methods of maintaining historical vaulted masonry structures, and is also used to improve the behaviour of newly designed masonry structures. This method of strengthening has its advantages, especially in the minimization of alterations to the structure and its simplicity of application. To compare the results and verify the vaults behaviour, experiments were performed with using a metallic helical reinforcement and non-metallic composite glass reinforcement. These experiments have demonstrated the significant influence of additional reinforcement on the carrying capacity of masonry vaults. The growth of bearing capacity was more than eight-fold. From a comparison of design approaches to experiments is evident that approaches to the design of additionally strengthened masonry based on valid standards are possible. The comparison of results moreover demonstrates the possibility of using approaches based on the Strut-and-Tie model.