1 Dynamic/Seismic analysis of RC Element including shear effect

2 ys yc Concrete Beam Stirrups From Lateral Equilibrium: Fiber model with Stirrups

3 Equivalent Uniaxial Stress: Rotating Crack Model Element in Cartesian Coordinate System Element in Principal Coordinate System cracks s1s1 s1s1 s2s2 s2s2 P Stress/Strain Model In Principal Directions

Material and Section Properties –Pier Height: 120 in –Concrete: 5930 psi –Longitudinal bar: 16-#8, Fy = 62 ksi –Spiral: #3, Fy = 75 ksi Plastic hinge zone: 2.5 in spacing Out of plastic hinge zone: 4.25 in spacing UIUC Reinforced Concrete Squat Column

UIUC Shear Response Reinforced Concrete Squat Column (PIER1 )  Shear Element is matching with the experimental data

Moment Response UIUC Moment Response UIUC Reinforced Concrete Squat Column (PIER1 ) UIUC Reinforced Concrete Squat Column (PIER1 )Moment Response UIUC Reinforced Concrete Squat Column (PIER1 )  Shear Element is matching with the experimental data

Axial Force Response Reinforced Concrete Squat Column (PIER1 )UIUC  Shear Element is matching with the experimental data

Shear Response UIUC Reinforced Concrete Squat Column (PIER2 )  Shear Element is matching with the experimental data

Moment Response UIUC Reinforced Concrete Squat Column (PIER2 )  Shear Element is matching with the experimental data

Axial Force Response Reinforced Concrete Squat Column (PIER2 ) UIUC  Shear Element is matching with the experimental data

RC column by Bousias et al. (1995)

Bousias Column Cyclic Comparisons

13 Dynamic/Seismic Analysis of Shear-Critical Elements Newmark Method –Constant Average Acceleration Method –Lumped Mass –Rayleigh Damping –Ground Acceleration/Dynamic Load

Bousias Column Earthquake Response

6.5” 20.25” 5” 10 kips 6.5” 5” Loading # 3 Longitudinal Bars Low - Moehle Beam Weak Axis Strong Axis

Low - Moehle Beam Monotonic Comparisons

Low - Moehle Beam Analysis by Spacone & Filippou

Low - Moehle Beam Earthquake Response

UMR Columns Monotonic Longitudinal Reinforcement Shell Region Core Region 2.5” Dia. 24” Dia. Transverse Reinforcement 12’

UMR Columns Monotonic Comparisons  For 6 ft column, increase the ductile behavior by changing the stirrup from #3 bar to #4 bar.

23 UMR Column Stirrup Strain

UMR Columns Cyclic Comparisons Contd.. 6’  With Shear element is failing at 1”, whereas Bernoulli element is still continuing..  With Shear element is failing at 1”, whereas Bernoulli element is still continuing..  With

UMR Columns Cyclic Comparisons6’ Column

UMR Columns Earthquake ResponseDisplacement  6ft column with shear has failed at initial times, where as others continued.

UMR Columns Earthquake ResponseResistance

Fiber Element Development- Schedule & Deadline ScheduleDeadline Finite element Analysis  Dynamic/Seismic analysis of RC bridge piers including shear effect  Development of RC fiber beam- column element including torsion/bending/axial interaction  Calibration of the parameters of the developed element  Development of an OpenSees version of the developed element Jan 08-Feb 08 March 08-May08 June 08-Aug 08 Sept 08-Oct 08