Bo made no secret of his desire to enter the nine-member Politburo Standing Committee (PSC) during the 18th Party Congress in autumn 2012, as all but two of the PSC members—including President Hu Jintao and Premier Wen Jiabao were expected to retire.
Except some cases of the partial PSC members reinforced with 420 MPa nonprestressed steel having the concrete cover depth over 60 mm or the full PSC members having the concrete cover depth over 120 mm, the allowable spacing of the tension reinforcements were always smaller in the PSC members than in the RC members.
The effect of the tension stiffening on Δf ps was greater in the full PSC members than that in the partial PSC members with PPR 50%.
Thus, this study also aimed at proposing a simple method to estimate Δf ps for the Class C PSC members.
Open image in new window Fig. 8 Effect of partial prestressing ratio on Δf ps. a PSC members with a low level of reinforcing index (RS1A series) and b PSC members with a high level of reinforcing index (RS7A series).
It also appeared that the stress change in Δf ps is more sensitive in the full PSC members compared to in the partial PSC members with respect to the magnitude of the effective prestress (f se ).
In PSC members, the increase in eccentricity of pre-stress force increases the growth of time-dependent strain.
This study, therefore, suggests that Δfps,allow can be 350 MPa for the partial PSC members with 550 MPa nonprestressed steels, while it is 250 MPa for the full PSC members and the partial PSC members reinforced with 420 MPa nonprestressed steels.
In PSC members the occurrence of creep and shrinkage of concrete and losses of pre-stress force are inter-related.
As shown in Fig. 10, in the case of the T-shaped sections, the minimum effective prestress (fse,min) can be determined as 0.5 f pu for all the full PSC members and the partial PSC members except the partial PSC members with 550 MPa reinforcements.
As shown in Table 1 and Fig. 2, the PSC members were rectangular, T-shaped, or inverted-T-shaped (IT-shaped).
