Volume 18 (2010): Issue 2 (June 2010)

Questions related to the occurrence, frequency, intensity, duration, characteristics and causes of floods have been discussed more in recent years. Two basic approaches to flood control often conflict. The first is based on the assumption of the considerable effect of a landscape's retention capacity, which can in fact prevent surface runoff generation and flood formation and can significantly transform flood wave. The second approach asserts that the retention capacity of a landscape is nearly negligible and that the only reliable flood protection can be provided by extending the technical structures of flood control measures mainly and directly on water courses. Two different approaches were applied to assess the effect of landscape conditions and revitalization measures on surface runoff and flood formation within a catchment and floodplain. The conclusion shows that the effect of landscape revitalization is very important, but mainly for low return periods of flood events, while for extreme events, the effect on landscapes and floodplains becomes less important and even negligible.

Wood is a polymeric material with many valuable features and which also lacks some negative features. In order to keep up with high construction rates and the minimization of negative effects, wood has become one of the most valuable materials in modern engineering. But the use of timber material economically is also an actual problem in order to protect the environment and improve natural surroundings. A panel of scientists is interested in solving these problems and in creating rational structures, where timber can be used efficiently. These constructions are as follows: glue-laminated (gluelam), composed and reinforced wooden constructions. Composed and reinforced wooden constructions are examined less, but according to researches already carried out, it is clear that significant work can be accomplished in creating rational, highly effective and economic timber constructions. The paper deals with research on the formation of composed fiber-reinforced beams (CFRP) made of timber and provide evidence of their effectiveness. The aim of the paper is to investigate cross-bending of CFRP-reinforced gluelaminated timber beams. According to the results we were able to determine the additional effectiveness of reinforcement with CFRP (which depends on the CFRP material's quality, quantity and module of elasticity) on the mechanical features of timber and a whole beam.

The Infrastructure for Geospatial Information consists of an information component, where the bearers of geoinformation are geospatial data, and a metainformation component. The bearers of metainformation are metadata, which describe these geospatial data. Metadata serve as a tool for discovery, retrieve and evaluation of geospatial data within the Infrastructure of Geospatial Information. In order to acquire metadata from a metadata producer to a metadata consumer, the implementation of various tools - components of Metainformation Infrastructure for Geospatial Information is required. This paper describes the main principles and components of Metainformation infrastructure and the possibility of using open source tools for their implementation in practice.

Many problems in Earthquake Engineering require the modeling of the structure as a dynamic system including the sub-grade. A structural engineer is usually familiar with the Finite Element Method but has a problem modeling the sub-grade when its infinite extension and wave propagation are the essential features. If the dynamic equation of a soil-structure system is written in a frequency domain and the variables of the system are total displacements, then the governing equations are given as in statics. The dynamic stiffness matrix of the system is obtained as the sum of the stiffnesses of the structure and sub-grade sub-structures. To illustrate the influence of the sub-grade on the dynamic behavior of the structure, the frequency response of two tower-like structures excited by a seismic harmonic wave field is shown. The sub-grade is modeled as an elastic homogeneous half-space. The structure is modeled as a finite beam element with lumped masses

Tall buildings can cause deformations of the earth's crust for long distances from the area of their realization. Monitoring the deformation of tall big buildings from geodetic networks realised near the building can also have deformations from this point of view, and analysis of the measurements can result in false conclusions. The loading effect of the earth crust must be excluded from the measurement parameters. The paper presents a model computation of the loading effect produced by tall buildings constructed of simple geometric forms on the earth's crust.