Study On Underwater Pier Reinforcement Technology By Precast Concrete Segment Assembled Quickly

In the process of bridge construction, various kinds of bridge damage have appeared one after another due to its service time and growth of traffic in China. For the pier is the only component to resist lateral force and the component to resist vertical force and once injured, it will seriously affect the work performance and even cause the collapse of the bridge due to its insufficient bearing capacity. In this paper, aiming at the underwater pier reinforcement technology and on the basis of summarizing the corresponding reinforcement technology research status, the author proposes the underwater pier reinforcement technology by precast concrete segment assembled quickly.First of all, experimental study on the effect of the reinforcement technology has been conducted and through the comparative analysis of the axial compression test including contrast specimen (original size and reinforcement size) and reinforced specimen (with and without FRP grid), we can see that the failure mode of the reinforced specimens has been improved significantly from brittle failure to ductile failure, the peak load and peak displacement of the reinforced specimens has been greatly increased and the percentage is 28%(reinforced specimen without FRP grid) or 63%(reinforced specimen with FRP grid) and 16%(reinforced specimen without FRP grid) or 44%(reinforced specimen with FRP grid) respectively, the mechanical properties of the reinforced specimens will be close to or even better than the contrast specimens(reinforcement size) through reasonable design, and the key parameters affecting the effect of the reinforcement technology are precast concrete segment connection performance, non-dispersion underwater concrete strength and constraint intensity.Then, using the finite element software ABAQUS for these three key parameters for further qualitative analysis, the results show that precast concrete segment connection performance will affect the stress distribution and the strength of the material to play and the relationship between the peak load and non-dispersion underwater concrete strength or constraint intensity is a linear correlation.On the basis of experimental study and finite element simulation and considering the reinforcement technology of augmented section method and constraint, the author proposes the theoretical model of the underwater pier reinforcement technology by precast concrete segments assembled quickly. By verifying the related experimental data, we find that the mode has a wide applicability.Finally, relaying on BeiGangHu Bridge, the author conducts a pilot project by using the underwater pier reinforcement technology by precast concrete segments assembled quickly and achieves a good reinforcement effect. Based on the project and research results, the construction process and quality control measures are proposed to guide the reinforcement design and construction.