For tackling the difficult problem of box-girder web crack,coming up with a new strengthening technology Lateral Tension for Vertical Prestress,and then try to do a simulation analysis with the finite element analysis software,checking out the effect and feasibility,find a new way for the long-span prestressed concrete box-girder web crack strengthening.

Study on the vertical prestress loss of the prestress concrete box girder bridge web;

Test of vertical prestress loss and analysis research on it;

The vertical prestress applied to webs of concrete box girder is studied.

In this paper,starting from analysis of the sensitivity of slant box beam web cracks to vertical pre-stress,the dynamic mechanism of the effective reduction in main web pulling stress by vertical pre-stress is explained.

The distribution of ring pre-stress, anchoring steel beam and pre-stress, vertical pre-stress of the anchoring zone of the main tower in Songhuajiang cable stayed bridge are introduced and the corresponding construction technologies are clarified in the paper.

The vertical pre-stressed reinforcement installed in the pre-stressed concrete continuous (rigid frame) box beam bridge is to decrease and control the main tension stress of the web and to prevent the creaking.

Based on the long-term field measurement of vertical prestress losses in the box girder of a long-span PC continuous bridge,a detailed analysis of the loss of the vertical prestressing is conducted.

Experimental Research on Flexural Performance of the Vertically Tensioned Prestressed Concrete Beams;

For the midspan sag of continuous rigid-frame bridge,scheme of using vertically tensioned prestressed techniques to regulate is proposed according to the features of external prestress on the basis of analysis of its advantages and disadvantages.

On construction technology of transverse prestressing in cast-in-place beam

this paper analyzed the wide concrete girder mechanical behavior under transverse prestressing by the spatial finite element method(FEM).

To ensure the integrity of the girder and resist transverse bending due to dead load and service load,powerful transverse prestressing tendons were disposed in the diaphragms.