Damage Monitoring and Field Analysis of Dynamic Responses of Ha Shuang Prestressed Concrete Box Girder Oblique Bridge before Strengthening

Abstract

Ha Shuang Bridge is located in Harbin city within Heilongjiang province in the east north of China. The purposes of this study are to monitor the damage in structural members of Ha Shuang prestressed concrete box girder oblique bridge before strengthening and to evaluate the dynamic performance of the bridge structure by adopting dynamic load test. Monitoring process of damage of the bridge structure shows that the web of box girder in the quarter of the second span (about 10.5m from the pier) suffers from serious shear cracks. These cracks extend from the top to lower flange of box girder. The width of cracks rang from 0.5mm to 2mm and the angle is 45 degree. There are 6 bending cracks. The spacing between these cracks rang from 20cm to 30cm and the width is 035mm. In the span No. 3 near the pier, the web of box girder appears 12 diagonal cracks have width rang from 0.1mm to 0.12 mm. The results of dynamic load test analysis show that the values of measured vertical natural frequency is w1 = 3.616Hz and horizontal natural frequency w2 = 4.492Hz less than the values of theoretical natural frequency which is 3.863Hz and 4.848Hz, indicating that the actual stiffness of the bridge structure is less than the theoretical stiffness. Therefore the dynamic working state of bridge structure is not good. Therefore the working state of bridge is not good and it need to repair and strengthening.

Structural Performance Evaluation of Reinforced Concrete Anaerobic Digester Tank in Sewage Treatment Plant: Investigational and Theoretical Study

“…Damages investigation of concrete structures and bridge components are conducted to determine whether a structure is safe, to spot any areas that require maintenance, repair, or strengthening, to serve as a planning tool for funding those areas, and to inform designers and construction engineers of those areas that require attention. In general, damages field investigation of the concrete structure's goals include assessing structural performance, locating actual and potential sources of damage as soon as possible, explaining to the member state whether the area is safe or unsafe, identifying any maintenance, repair, and strengthening that needs to be done, and classifying the damaged parts of the bridge members [22][23][24][25][26][27][28].…”

Probabilistic Safety Factor Calculation of the Lateral Overturning Stability of a Single-Column Pier Curved Bridge under Asymmetric Eccentric Load

“…Hong Li and Ricardo O. Foschi [26] proposed a direct algorithm to solve for these parameters. The basic idea of the algorithm is that β T is known, and we solve for θ (or the mean value of θ), such the parameters to be solved meet min(u T u) = β 2 T and G = G(u, θ) = 0.…”

“…A single or similar single-column cast-in-situ continuous box girder structure is often used in urban overpass and trunk highway bridges in China. Single or similar singlecolumn pier box girder bridges have the characteristics of light structure, reduced land occupation, improved substructure layout, increased vision, and beautiful bridge type [1][2][3]. However, many bridge overturning accidents have occurred during the use of this structural form (see Table 1).…”