The problems like cracking of the girder in the mid-span and the ever-increasing vertical deflection appear during the long term usage of the long-span continuous rigid-flame bridge. Post-tension tendon with re- serve...The problems like cracking of the girder in the mid-span and the ever-increasing vertical deflection appear during the long term usage of the long-span continuous rigid-flame bridge. Post-tension tendon with re- served duct can increase the pre-stress of the main beam effectively, and decrease the long term span deflection in order to improve the performance of the girder. At the same time, the proper tension position is very crucial to optimise the stress distribution of the bridge and control the deflection increase. Combining with practical en- gineering, the authors analyze the influence of different positions of post-tension tendon （ including top-, web- and bottom plate tendons） on the stress and deflection of the main beam, and find out the optimal position of post tendon.展开更多
China has quickly risen to the top ranks in global energy demand over the past few years.China is the world’s second-largest oil consumer behind the United States and became the largest global energy consumer in2010....China has quickly risen to the top ranks in global energy demand over the past few years.China is the world’s second-largest oil consumer behind the United States and became the largest global energy consumer in2010. The country was a net oil exporter until the early 1990s and became the world＇s second-largest net importer of crude oil and petroleum products in 2009. Then the country became the world＇s largest oil importer in 2014. Meanwhile, China＇s oil consumption growth accounted for one-third of the world＇s oil consumntion growth展开更多
文摘The problems like cracking of the girder in the mid-span and the ever-increasing vertical deflection appear during the long term usage of the long-span continuous rigid-flame bridge. Post-tension tendon with re- served duct can increase the pre-stress of the main beam effectively, and decrease the long term span deflection in order to improve the performance of the girder. At the same time, the proper tension position is very crucial to optimise the stress distribution of the bridge and control the deflection increase. Combining with practical en- gineering, the authors analyze the influence of different positions of post-tension tendon （ including top-, web- and bottom plate tendons） on the stress and deflection of the main beam, and find out the optimal position of post tendon.
文摘China has quickly risen to the top ranks in global energy demand over the past few years.China is the world’s second-largest oil consumer behind the United States and became the largest global energy consumer in2010. The country was a net oil exporter until the early 1990s and became the world＇s second-largest net importer of crude oil and petroleum products in 2009. Then the country became the world＇s largest oil importer in 2014. Meanwhile, China＇s oil consumption growth accounted for one-third of the world＇s oil consumntion growth
