Search results

Filters

  • Journals
  • Authors
  • Keywords
  • Date
  • Type

Search results

Number of results: 3
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

This article presents the results of laboratory tests of the physical and mechanical properties of various types of sandstone selected from ten quarries from Carpathian flysch. The parameters were used to evaluate the quality of the sandstone and its suitability for use as armourstone in accordance with applicable standards and quality guidelines. The requirements of the BN-79/8952-31, EN 13383-1:2003 and the CIRIA, CUR, CETMEF (2007) standards were compared. Sandstone can display a large variability of parameters depending on its origin. This, in turn, results in a varying degree of its susceptibility to the destructive effects of water and climate.

Go to article

Authors and Affiliations

Joanna Hydzik-Wiśniewska
Agnieszka Pękala
Download PDF Download RIS Download Bibtex

Abstract

The maintenance of dams, including the protection of reservoir and flood embankments, requires regular control measurements and assessment of their technical condition. The choice of measurement methods, especially in terms of their speed and reliability, become crucial especially when the facilities are endangered due to a natural disaster. However, despite the enormous rapid development of modern geodetic measurement techniques, measurements at most dams are still conducted using classical techniques, such as angular-linear or leveling measurements which require interference with the measured structure. In addition, they need to be personally performed by employees or require visual inspections of the structure or in its protection zone. This article presents non-contact geodetic measurement techniques, such as terrestrial laser scanning, remote sensing classification of intensity and thermovision images recorded with various measurement sensors, digital image correlation, digital photogrammetry, or UAV. They are presented and compared in terms of their reliability, efficiency and accuracy of the obtained data, and the possibility of their automation and integration. As surveyors and hydraulic and geotechnical engineers are increasingly turning to modern measurement technologies, the aim of this paper is to help in selecting appropriate and effective monitoring tools ensuring fast and safe measurements crucial for the safety and maintenance of concrete structures. It presents examples of research based on the use of the modern measuring techniques carried out in recent years by employees of the Faculty of Geodesy and Cartography at the Warsaw University of Technology.
Go to article

Authors and Affiliations

Janina Zaczek-Peplinska
1
ORCID: ORCID
Maria Kowalska
1
ORCID: ORCID

  1. University of Technology, Faculty of Geodesy and Cartography, Pl. Politechniki 1, 00-661 Warsaw, Poland
Download PDF Download RIS Download Bibtex

Abstract

More than 4.6 mln ha in the Russian Federation are irrigated. Their culvert hydraulic structures are part of network structures and are the most widespread. After the crisis of the 1990s, proper maintenance of many reclamation systems was impossible due to a lack of funds. This led to the loss of about half of the water taken from irrigation sources in irrigation canals. The planned increase in the technical level of irrigation systems requires the automation of the operation of both the entire system as a whole and separately located culverts. This will avoid significant losses of water supply for irrigation and prevent water shortages with the insufficient discipline of water users. Means of hydraulic automation of water supply are being installed on small irrigation canals in Russia. A water flow regulating valve is proposed, with no mechanical movinparts, and gates are not involved in the control process. The operation of the structure is based on the injection effect, in which excess water entering the downstream with a decrease in water consumption begins to circulate between the outlet section of the transit pipe and the diffuser at the end section of the valve. Using the methods of measuring hydrodynamics and the theory of jet devices, theoretical dependences were obtained, which make it possible to determine the main hydraulic characteristics of the structure. The design form of the flow part of the regulator has been developed and a physical model has been made. In a mirror hydraulic flume, the operation modes of the water outlet were studied with and without regulation. The actual values of hydraulic parameters were obtained, which confirmed the validity of the use of theoretical dependencies. The discrepancy between the theoretical and experimental results is within the experimental error. It has been proven that it is possible to circulate excess water between the downstream and intermediate pools of the regulator.
Go to article

Authors and Affiliations

Dmitrii M. Benin
1
Vera L. Snezhko
1

  1. Russian State Agrarian University – Moscow Timiryazev Agricultural Academy, Timiryazevskaya St, 49, Moscow, 127550, Russia

This page uses 'cookies'. Learn more