Abstract. In the article, the authors discuss the preliminary information necessary to determine the scope and direction of further research conducted within the project called "The influence of time and operating conditions on the durability and functionality of road safety elements". The main objective of the project is to develop the concept of a method for optimizing the life cycle costs of road safety devices. The authors draw attention to the close connection between the decisions taken at the design stage and expenses incurred in the course of maintenance and the use of road safety devices, present the specificity of road infrastructure in terms of life cycle costs, discuss the components of the costs and give examples of the LCC analysis applied to the concrete barrier.

A b s t r a c tSteel materials, due to their numerous advantages -high availability, easiness of processing and possibility of almost any shaping are commonly applied in construction for carrying out basic carrier systems and auxiliary structures. However, the major disadvantage of this material is its high corrosion susceptibility, which depends strictly on the local conditions of the facility and the applied type of corrosion protection system. The paper presents an analysis of life cycle costs of structures installed on bridges used in the road lane conditions. Three anti-corrosion protection systems were considered, analyzing their essential cost components. The possibility of reducing significantly the costs associated with anti-corrosion protection at the stage of steel barriers maintenance over a period of 30 years has been indicated. The possibility of using a new approach based on the life cycle cost estimation in the anti-corrosion protection of steel elements is presented. The relationship between the method of steel barrier protection, the scope of repair, renewal work and costs is shown. The article proposes an optimal solution which, while reducing the cost of maintenance of road infrastructure components in the area of corrosion protection, allows to maintain certain safety standards for steel barriers that are installed on the bridge.

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The purpose of the research was to assess the possibility of using granulated expanded glass aggregate (GEGA) with cement grout as a replacement of a sub-grade and frost-protection layer, made of natural fine aggregates (NATU), stabilized with a hydraulic binder. Instead of traditional parts of the road construction, such as the sub-grade and frost-protection layer with the application of fine aggregate, stabilized with cement, the authors propose only one layer, made of lightweight water-permeable material, containing GEGA with a grain size from 8 to 11.2 mm. In the article the authors present the physical properties of the materials, applied for the road layers, the properties of the fine aggregate, stabilized with cement, and those of the cement composite with GEGA as an alternative solution. The laboratory test results of fine aggregates, stabilized with cement and of cement composites with GEGA, are presented. Porosity, volume density, compressive strength, and frost resistance are being researched. The results of those tests are meant to play an essential role in designing the thickness of road layers. Different types of pavement structure (asphalt and concrete) and different values of road load are being considered in the given work. The paper is concluded with considerations on an innovative solution, involving the use of ecological materials.

By signing a contract for construction works each of the parties assumes a specific scope of responsibility. In practice, there are numerous examples of contractual provisions that violate the parties' safety and the balance of fair and even distribution of risk. Asymmetry in risk allocation in construction contracts and its consequences is the most common cause of disputes between the parties. The article presents the issue of risk distribution and its consequences on the example of selected construction contracts provisions.