Techniques to Replace Piers of Existing Bridge Without Traffic Disruption
The expanded subgrade of the main line of Zhongshan-Jiangmen Expressway in Guangdong Province has sections underpassing the C and E ramps of the Sicun Interchange.The piers C18 and E12,each consisting of two circular columns,served as the transition piers and stood in the way of the expanded subgrade,which had to be replaced to leave space for the construction of the subgrade.To ensure the structural safety of the existing bridge,the original two two-column piers were replaced to be a portal-frame pier with a long cap beams and a portal-frame pier with a concealed cap beam,respectively.The influence of pier replacement on the load bearing behaviors of the ramps was analyzed.It is shown that the load bearing performance of the ramps after pier replacement still meet the requirements.During replacement,the new piers were constructed first,once gaining the required load bearing capacity,the existing piers were cut off,and the system transformation ensued.To reduce the influence of pier replacement on the service of the existing ramps and ease the system transformation,the cap beam of the pier C18 were set to enclose the head of the existing pier columns,while the concealed cap beam of pier E12 was fixed with the deck,with independent portal-frame piers at the two sides of the expansion joint.
万方数据
维普
