Analysis On The Early Cracks Of Concrete Bridge Deck Pavement And Study On Repair Materials

Concrete Bridge deck is a pavement structure, which can protect the bridge deck and pavement. But now the main damage of bridge deck pavement is the early cracking. This paper discussed some factors that affect the early cracks of concrete bridge deck pavement from the following aspects, and studied on the cracks repair.1. Studied on the factors of early shrinkage cracking. The main research of the mineral admixture and the influence of water cement ratio on concrete plastic cracking, effects of different admixture influence on the early shrinkage of concrete on bridge deck pavement and construction technology. The results show that:the mineral admixture increases the average crack area and total crack area mineral admixtures suggested about20%of fly; the decreasing of water cement ratio will make concrete plastic cracking ahead of time, when the water cement ratio lower than0.4the influences significantly increase; fiber mixed with fly ash can significantly reduce the shrinkage of concrete, fly ash could significantly prolong the time of plastic cracking; should standardize the construction process and technology.2. Studied on the effect of fiber on concrete strength and the influence of reinforcement ratio on reinforced concrete axial tensile. The results show that:the incorporation of fibers decreases the compressive strength of concrete, but increases splitting tensile strength, bending strength, axial tensile strength and deformation capacity of the matrix concrete, and the strength is impacted by multi-scale and volume fiber; the reinforcement ratio for initial cracking impact is very little, but quantity of reinforcement in the form of fine diameter can be more effective in controlling the development of crack width.3. According to the actual use of the deck surfacing in the process of fracture mode, set up two kinds of mathematical model based on some assumption conditions. For two models of concrete stress, steel bar stress, concrete displacement, crack width and so on are analyzed, and the problem is solved by iteration method.4. Studied on the repair cracks of the bridge deck pavement. The main research is the properties of epoxy patching, and identifies its relevant mix.The research achievement can be used in the design of bridge deck pavement materials, reinforcement ratio and cracks repair.