tailieunhanh - Substructures of Major Overwater Bridges

Substructures of Major Overwater Bridges Introduction Large Diameter Tubular Piles Description • Offshore Structure Practice • Steel Pile Design and Fabrication • Transportation and Upending of Piles • Driving of Piles • Utilization of Piles in Bridge Piers • Prestressed Concrete Cylinder Piles • Footing Blocks 47 Cofferdams for Bridge Piers Description • Design Requirements • Internally-Braced Cofferdams • Circular Cofferdams • Excavation • Driving of Piles in Cofferdams • Tremie Concrete Seal • Pier Footing Block • Pier Shaft Open Caissons Description • Installation • Penetration of Soils • Founding on Rock • Contingencies. | Gerwick Jr. . Substructures of Major Overwater Bridges. Bridge Engineering Handbook. Ed. Wai-Fah Chen and Lian Duan Boca Raton CRC Press 2000 47 Substructures of Major Overwater Bridges Introduction Large Diameter Tubular Piles Description Offshore Structure Practice Steel Pile Design and Fabrication Transportation and Upending of Piles Driving of Piles Utilization of Piles in Bridge Piers Prestressed Concrete Cylinder Piles Footing Blocks Cofferdams for Bridge Piers Description Design Requirements Internally-Braced Cofferdams Circular Cofferdams Excavation Driving of Piles in Cofferdams Tremie Concrete Seal Pier Footing Block Pier Shaft Open Caissons Description Installation Penetration of Soils Founding on Rock Contingencies Pneumatic Caissons Description Robotic Excavation Box Caissons Description Construction Prefabrication Concepts Installation of Box Caissons by Flotation Installing Box Caissons by Direct Lift Ben C. Gerwick Jr. Positioning Grouting Ben C. Gerwick Inc. and University Present and Future Trends of California Berkeley Introduction Present Practice Deep Water Concepts The design and construction of the piers for overwater bridges present a series of demanding criteria. In service the pier must be able to support the dead and live loads successfully while resisting environmental forces such as current wind wave sea ice and unbalanced soil loads sometimes even including downslope rock fall. Earthquake loadings present a major challenge to design with cyclic reversing motions propagated up through the soil and the pier to excite the superstructure. Accidental forces must also be resisted. Collision by barges and ships is becoming an increasingly serious hazard for bridge piers in waterways both those piers flanking the channel and those of approaches wherever the water depth is sufficient. 2000 by CRC Press LLC Soil-structure foundation interaction controls the design for dynamic and impact forces. The .