Disadvantages of prestressed concrete structures
Concrete Steel Structure 1. The process is more complex, high quality requirements, thus requiring a more skilled professional team, and there are problems of interspersed types of work. 2. Sub-stress. Secondary stresses due to prestressing, creep and shrinkage effects, temperature variations, and bearing subsidence can be severe in continuous structures unless these are controlled or accounted for in the design. In prestressed continuous structures, it is interesting to note that these secondary stresses can often be exploited advantageously, and thus the secondary stresses will increase the economy of the structure. 3. Friction losses in continuous force bars. Friction losses can be significant if there are many reverse curves, if the curves have large deflection angles, or if the force bars are too long. In beams with corrugations or added axils, friction losses can be minimised by using straighter cables. The usual methods of over-tensioning and tensioning from both ends can ...