Design and Application of Partially Unbonded Prestressed Concrete Structures

Prestressed concrete structures can be divided into bonded and non-bonded structures. This paper innovatively presents a new type of partially unbonded prestressed concrete structures. The structural form can not only ensure the full section compression of the structure through prestressing, but also improve the shear resistance and waterproof capacity of the segment joints. It can also release the internal moment force through the millimeter level expansion of segment joints, reducing the amount of prestress. The new structure has been successfully applied to the construction drawing design of the immersed tube tunnel of the Hong Kong-Zhuhai-Macao Bridge, and has effectively supported its innovation of the semi-rigid pipe-joint structural system.