Key Technique Schemes for Construction of Steel and Concrete Joint Section of Edong Changjiang River Bridge

The main bridge of Edong Changjiang River Bridge is a semi-floating system continuous hybrid girder cable-stayed bridge with a main span 926 m and the steel and concrete joint section of the Bridge is the critical part in the construction of the box girders for the whole main bridge.In the construction,the steel box girder at the girder section M(non-standard) was lifted and installed by the 1 200-t capacity Zhenhanggong 818 Floating Crane and the girder was accurately adjusted and positioned by the adjusting system made up of the temporary bearings and jacks.At the girder section L,the steel fiber concrete having good cracking resistance performance was selected.The concrete was pumped by the movable pumps,distributed to place in layers through hoses,cast symmetrically and vibrated by the immersion vibrators.The smooth construction of the steel box girder at the girder section M indicates that the scheme prepared for the lifting,installation and positioning of the box girder is rational.The completed concrete for the testing part of the steel and concrete joint section is solid and is visually pleasing to the eye,which verifies the excellence of the mix proportioning for the steel fiber concrete and the feasibility of the concrete casting scheme for the girder section L as well as the cracking-proof measures taken in the construction.