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Code provisions for a simplified check of the long‐term deflection of concrete structures are generally developed for predefined values of the relevant input parameters. Deflection calculation may be of interest to account for different design situations. EN 1992‐1‐1 advocates the integration of curvatures calculated using the effective modulus of concrete. This paper presents an efficient procedure for calculation of the long‐term deflection due to a sustained load. A nondimensional analysis of the mean curvature is applied to evaluate the deflection. The deflection is calculated using a set of algebraic expressions. The result is close to the value obtained by the numerical integration of curvatures. The values of relevant parameters in the expressions may be selected within the common range for the design of engineering structures. The efficiency of the deflection prediction based on the integration of curvatures is tested on the available experimental data. In the first approach, the measured material properties are used. In the second approach, the required values are derived from EN 1992‐1‐1 expressions to predict the material properties.

<p>Infrastructure managers works every day according to some kind of Quality Control Plan (QCP) in order to ensure a desired quality with minimum traffic interruption balancing cost, risks (implicit or explicit) and performance. These QCPs varies significantly among European countries, which urges the establishment of a common European guideline. COST TU1406 Working Group 3 has the aim of providing a detailed explanation of the steps towards the establishment of a QCP. The approach is generic and evaluates performance values with due attention to: 1) Structure and its constitutive element incl. background material such as birth certificates, 2) Time-dependent Performance Indicators (PI) from observations (e.g. spalling) with due reference to the underlying deterioration processes (e.g. alkali-silica reaction) and 3) Related Key Performance Indicators (KPI) based on the Dutch risk-driven maintenance concept RAMSSHE€P [1]. This paper outlines QCP's for concrete girder and frame bridges.</p>

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Tools, guidelines and standards for assessment of Life Cycle Cost (LCC) of built environment e.g. buildings, infrastructure assets etc. have gained impact over the past years. Owner and operator application of tools, guidelines and standards enhances optimization of operation and maintenance with due respect to their budgets. In order to aid owners, operators and their designers, a task group under fib has been established to prepare a state-of-the-art report regarding LCC analyses of concrete assets. The state-of-the-art report contains a description of existing LCC standards and guidelines, their applicability, the definition of different cost elements, and the treatment of uncertain information in a reliability or risk based framework, etc. providing the reader with background information and methodology for preparation of such analysis. Moreover, the report contains case studies, presenting the applicability of the LCC analysis methodology.

<p>The state-of-the-art Bridge Management Systems (BMSs) feature tightly coupled deterioration and preservation optimization model that enable determining the most cost-effective maintenance strategies at both the project and network levels. In other to improve deterioration model, many authors suggest the application of Weibull distribution for the sojourn time in condition states. Consequently, one has to solve semi-Markov decision process to determine the optimum preservation policy. It can be shown that the long-run optimal policies obtained using semi- Markov model doesn’t differ from those of time homogenous Markov chains for average cost criteria if the expected sojourn times in each condition state are same for both model. However, financial needs differ between the models depending on distribution parameters of sojourn time in each condition state. It is therefore that the estimation of these parameters is crucial for the realistic estimation of the financial needs. In this paper, the semi-Markov decision process is briefly presented and recommendations regarding its practical applications in bridge management are given.</p>

The subject of this paper is heavy-duty transport in the Republic of Serbia. Permits for heavy-duty transport issued by the public company Roads of Serbia for two representive months: April and September in 2019 were considered. The following data from permits were analyzed: dimension of vehicle, number of axles, total vehicle weight and axle overload. The first part of this paper presents short review of the current analysis of heavy-duty transport in Europe and the world over the last 20 years, and also trends and expectations in the future. Second part of this paper represent statistical processing and analysis of data from permits of heavy-duty transport. On the end of this paper are given conclusions based on analysis of data from permits.

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