4.14.2.9. FRPConfinedConcrete¶
- uniaxialMaterial('FRPConfinedConcrete', matTag, fpc1, fpc2, epsc0, D, c, Ej, Sj, tj, eju, S, fyl, fyh, dlong, dtrans, Es, nu0, k, useBuck)
This command is used to construct a uniaxial Megalooikonomou-Monti-Santini concrete material object with degraded linear unloading/reloading stiffness according to the work of Karsan-Jirsa and no tensile strength.
matTag
(int)integer tag identifying material
fpc1
(float)concrete core compressive strength.
fpc2
(float)concrete cover compressive strength.
epsc0
(float)strain corresponding to unconfined concrete strength.
D
(float)diameter of the circular section.
c
(float)dimension of concrete cover (until the outer edge of steel stirrups)
Ej
(float)elastic modulus of the fiber reinforced polymer (FRP) jacket.
Sj
(float)clear spacing of the FRP strips - zero if FRP jacket is continuous.
tj
(float)total thickness of the FRP jacket.
eju
(float)rupture strain of the FRP jacket from tensile coupons.
S
(float)spacing of the steel spiral/stirrups.
fyl
(float)yielding strength of longitudinal steel bars.
fyh
(float)yielding strength of the steel spiral/stirrups.
dlong
(float)diameter of the longitudinal bars of the circular section.
dtrans
(float)diameter of the steel spiral/stirrups.
Es
(float)elastic modulus of steel.
nu0
(float)initial Poisson’s coefficient for concrete.
k
(float)reduction factor for the rupture strain of the FRP jacket, recommended values 0.5-0.8.
useBuck
(float)FRP jacket failure criterion due to buckling of longitudinal compressive steel bars (0 = not include it, 1= to include it).
Note
#.IMPORTANT: The units of the input parameters should be in MPa, N, mm. #.Concrete compressive strengths and the corresponding strain should be input as positive values. #.When rupture of FRP jacket occurs due to dilation of concrete (lateral concrete strain exceeding reduced rupture strain of FRP jacket), the analysis is not terminated. Only a message “FRP Rupture” is plotted on the screen. #.When $useBuck input parameter is on (equal to 1) and the model’s longitudinal steel buckling conditions are fulfilled, a message “Initiation of Buckling of Long.Bar under Compression” is plotted on the screen. #.When rupture of FRP jacket occurs due to its interaction with buckled longitudinal compressive steel bars, the analysis is not terminated. Only a message “FRP Rupture due to Buckling of Long.Bar under compression” is plotted on the screen.
See also