Vízügyi Közlemények, 1996 (78. évfolyam)

4. füzet - Muszkalay L.-Varsa E.: A kiskörei duzzasztómű függőleges mozgásának vizsgálata

422 Muszkalay L— Varsa E. surveyed ever since its construction by the Water Resources Research Centre VITUKI, and or recently by VITUKI Consult. As shown in Figure 2. one upstream and one downstream control points had been installed in each of the piers of the river barrage. The vertical position of these control points have been regularly determined by advanced levelling methods. Results of these height surveys have been taken into consideration since the 28th of July, 1972, after the construction work and the primary phase of consolidation had taken place. Sixty surveys have been made since this date and the 24th of May, 1993. The method of these investigations relies on physical basis, using the techniques of mathematical statistics. The method essentially is based on deriving the components that determine vertical movement from the basic data, using physical relationships and the on checking the reliability of these measures by mathematical-statistical means. These components are as follows: Thermal expansion, flexible deformation of the subsoil and the lasting subsidence of the structure. After having these components derived from the records of pier height, the so called residual time series must be of the normal distribution type. Cumulated statistical parameters are being used for this purpose. Figure 3. shows the relationships between pressure and the flexible transformation of the subsoil for pier VI., as derived from the corresponding height and load differences. Characteristics of the relationship between load and the flexible deformation of the subsoil are shown in Table II. The function of permanent subsidence is shown in Figure 4. These curves show the hypothetic elevation that would have been assumed, in a given point of time, by the piers at 0 °C temperature, if there was no load on them. The outstanding practical significance of these functions is that the lasting (permanent) subsidence of a given pier, as compared to the value of the function at zero point of time, can be obtained for any point of time. Table II shows the actual subsidence of each of the piers between July 28 1972 and 24 May 1993, along with the forecasted permanent subsidence of the years 2000 and 2020. From the point of view of the safety of operating the structures, the sector gates, and from that of the stability of the operating bridge it is essential to know how large could be, under extreme conditions, the elevation difference between the piers. A reliable estimation of these differences is given in Table III. The residual function of pier VI. is shown in Figure 5., along with the cumulated functions of the corresponding statistical parameters. An important measure of the residual function is the standard deviation, which provides information on the reliability of measurement data and on the changes of the tendencies of motion that have taken place. Table IV. shows, on the basis of the full set of data, the standard deviation of the residual functions, that of the primary measurement data and of the elevation values that have been obtained in the various steps of the calculation procedure. Tilting, as shown in Table V. is interpreted as the difference of the elevation of the control points of the upstream and downstream sides of the piers. A new and the possible most accurate method has been developed for the investigation of the vertical displacement of the Kisköre River Barrage. This method can be applied for any hydraulic structure that has similarly long measurement records. The method relies on physical laws and utilizes the techniques of mathematical statistics.Regarding the piers of the Kisköre River barrage it was found that the permanent subsidence of the piers is decreasing in function of the time. It is likely, however, that the subsidence of Pier VI. is affected by the motions of the navigation lock. Statical investigations of the operation bridge became necessary, due to the uneven subsidence of its supports, the piers. * * *