Prestressed steel reinforced high-strength concrete (PSRHC) beams possess high load-carrying capacity and small section dimension
which is applicable to long-span and heavy-load buildings. To investigate the various design parameters' effects on the ductility of PSRHC beam members
the static behavior of PSRHC beam was simulated with numerical method and multi-parameter analysis was carried out. Based on the section fiber model
an analysis method
which could consider the confined effect of hoops
was firstly established to simulate the static behavior of PSRHC beams. Result shows that the analysis result has a good agreement with the test load-deflection curves. Then
the effect of parameters
including concrete class
amount of tension and compression rebar and prestress tendons
thickness of steel flange and web
and diameter and space of hoops
on the ductility of PSRHC beams was investigated. The results imply that: raising the concrete class
increasing the amount of compression rebar and hoops can improve the ductility of PSRHC beam members; increasing the amount of tension rebar
prestress tendons and thickness of steel web would decrease the ductility; and the effect of flange thickness is not obvious. When the hoop-space increases from 50 mm to 200 mm
the ductility coefficient decreases about 20.6%
and the diameter of hoop improves from 6mm to 10mm
the coefficient increases various from 18% to 34%. Finally
according to the simulation results
a regression formula
containing two parameters of hoops-volumetric ratio and complex reinforcement index
was proposed to evaluate the ductility of PSRHC members
and 3.1 was selected as demarcation value in this formula.