| Popis: |
The construction of a new strategically very important bridge, crossing the sea strait between the Croatian Mainland and the Pelješac Peninsula, to provide the fixed road link between the whole of Croatia, currently separated by a small coastal stretch belonging to the state of Bosnia and Herzegovina, has just begun. The four lane road bridge consists of two approach bridges and the main cable stayed bridge with continuous steel trapezoidal box superstructure to both abutments. The overall bridge length is 2.404m, extending over 17 spans with lengths of 72, 0+96, 0+5x120, 0+150, 0+568, 0+150, 0+5x120, 0+96, 0+72, 0 m. The sea depth is approximately 26m. Bridge foundations in the strait comprise battered steel pipe piles 100m in length, partly filled up with concrete and concrete pile caps at sea level. Extensive off-shore site investigations were carried out, including continuous shear wave survey and geotechnical explorations from a specially equipped drill ship, to obtain soil parameters for the design of bridge foundations. A site-specific seismic study was undertaken based on the seismic source zone characterization and attenuation relationships for the south of Croatia. The bridge site is also open to high winds with maximum average 10-minute wind speeds of 33.4 m/s and wind gust speeds of 47.1 m/s, both for the return period of 50 years and most unfavourable SE wind direction according to estimates of the Croatian Meteorological Service. Design actions including appropriate combinations of actions for the Peljesac Bridge were defined on the basis of Eurocodes, DIN 1054 and DIN FB Bridge Design Recommendations. |
