Study On The Construction Technique Of Transverse V-shaped Pier With Columns Of Unequal Height

Due to its structural novel and elegant apperance, the V-shaped piers are widely used in the urban and scenic spot rigid frame bridges. The common V-shaped pier is a longitudinal inverted-triangle rigid frame, which consits of two inclined columns and a transverse tie between the top ends of two columns. In the transverse direction, it has a wall-shaped front view and has basically the same width of the above superstructure. In the Changxing harbour bridge located in the around Taihu Lake highway, a kind of different V-shaped piers is constructed, which is a single column in side view, and however V-shaped in the transverse direction. The two inclined columns have different height, and support the different bridge decks. A inclined transverse tie is installed to link the top ends of two inclined columns, and also carries the large horizontal force caused by its selfweight and the loads handing down from the superstructures. This kind of pier structure is very rare in the bridge construction both at home and abroad, its mechanics performance and construction are obviously different from the commonly used column-shaped pier or lotus-shaped pier. Therefore, new problems and challenges are brought forward for its design and construction.In this paper, taking the Changxing Harbour Bridge as engineering example, through theoretical analysis and engineering practice, research on the key construction technology of transverse V-shaped pier with columns of unequal height has been conducted, its mechanics performance during construction is also investigated, and the favorable formwork supporting system of the inclined columns, the prestressed tension of the inclined tie, the concrete casting procedure of the inclined columns and the crack prevention control measures of the pier bottom are also studied to ensure sufficient strength, rigidity and stability of the pier during its construction, which can provide technical guide for the similar bridge construction.It is indicated through the research and engineering practice that using the crane with the hopper, the barrels and the plug-in vibrators successfully resolves the pouring difficultity of small slump concrete; the steel mesh in the inclined tie beam can effectively block concrete to flow downwards, and thus improves the construction quality of the inclined tie beam; using the reserve construction joints and closed measures effectively prevents concrete crack at the bottom; the obtained construction technique has the advantages of convenient construction, low construction cost, good concrete pouring quality, and significant economic and social benefits, and is therefore worthy to be popularized in the similar engineering projects.