Research On Design And Application Of ECC Flexible Bridge Deck Link Slabs

Being under long-term exposure in the atmosphere and subjected to the impact of vehicle loads directly, bridge expansion joints are subject to damaging easily and need frequent maintenance, which not only affects the traffic but also increases the project cost. Although many improved designs and a lot of better maintenance and repair methods such as using high-performance fiber reinforced concrete, high strength concrete or epoxy resin coating, have been proposed over the years, their effects are not good enough and there are many defects and shortages, so the problems have not been solved fundamentally. Recently, a new cementitious composite----ECC material is getting more and more attention in the field of civil engineering because of its outstanding properties in anti-crack and anti-deformation. In view of this, in order to meet the deformation needs induced from the temperature and so on, how to use the ECC material to design flexible bridge deck link slabs, instead of traditional expansion joints, is an attempt in the paperFor the reason that ECC material has unique properties -the excellent ability of cracks control and the good ability of strain, so, using ECC material to construct flexible bridge deck link slabs not only can meet the needs of the temperature deformation, but also can reduce and prevent cracks in the bridge structure. Meanwhile, the durability of bridge structures can be improved and good long-term economic benefit can be achieved.Destruction reasons, design method and deficiencies of traditional expansion joints are analyzed, the design process of a new deck connection structure-ECC deck link slab, and its calculation methods as well as problems that may be faced during the calculation and their solutions are investigated, the construction techniques of ECC deck link slabs and large scale mixing of ECC materials are discussed, and some opinions and suggestions on researches and applications of the ECC deck link slab in our country are proposed in the paper.The link slab is not only able to make a travelling smooth and comfortable, but also increase the bridge durability and prevent the bridge leaking phenomenon. Meanwhile, the ECC material is a high-toughness and ductile concrete, which has a strong ability to absorb energy and is helpful to anti-earthquake of bridge structures. To use ECC link slabs, instead of traditional expansion joints, don't change the nature of simply supported bridges and solves the crack problems whick exit in the connection interface of expansion joints and the girder end, so it is necesarry to promote the application in China.