150 likes | 155 Views
EFFECT OF LARGE OPENINGS IN UNBONDED POST-TENSIONED PRECAST CONCRETE WALLS. Michael Allen Yahya C. Kurama University Of Notre Dame Notre Dame, IN. ELEVATION. anchorage. wall panel. unbonded PT bar. horizontal joint. spiral reinforcement. foundation. WALL WITH OPENINGS.
E N D
EFFECT OF LARGE OPENINGS IN UNBONDED POST-TENSIONED PRECAST CONCRETE WALLS Michael Allen Yahya C. Kurama University Of Notre Dame Notre Dame, IN
ELEVATION anchorage wall panel unbonded PT bar horizontal joint spiral reinforcement foundation
WALL WITH OPENINGS gravity load lateral load opening gap
BASE PANEL compression stresses shear stresses
CRACKING 5 2 1 3 4 3 1 2 5
FINITE ELEMENT MODEL nonlinear plane stress elements truss elements contact elements
ABAQUS VERSUS DRAIN base shear (kips) 1000 yielding state 500 gap opening state ABAQUS DRAIN 0 0.5 1 1.5 2 2.5 roof drift (%)
ABAQUS VERSUS DRAIN contact length / wall length 1.0 ABAQUS DRAIN 0.5 0 0.5 1 1.5 2.5 2 roof drift (%)
BUILDING LAYOUT FOR HIGH SEISMICITY 8 x 24 ft. = 192 ft. gravity load frame lateral load frame hollow- core panels wall N 110 ft. S inverted T-beam column L-beam
WALL WH1CROSS SECTION C L PT bars ap=1.5 in2 (9.6 cm2) fpi=0.60fpu #3 spirals rsp=7% 12 in (31 cm) 10 ft (3 m) half wall length
PARAMETRIC INVESTIGATION • opening size • opening location • prestress level
OPENING SIZE lp=20 feet ho hp=16 feet lo lo 2 feet (0.10 lp) 4 feet (0.20 lp) 6 feet (0.30 lp) 8 feet (0.40 lp) 10 feet (0.50 lp) ho 2 feet (0.13 hp) 4 feet (0.25 hp) 6 feet (0.38 hp) 8 feet (0.50 hp)
OPENING LOCATION lo ho = 6 feet y lo 2 feet (0.10 lp) 4 feet (0.20 lp) 6 feet (0.30 lp) 8 feet (0.40 lp) 10 feet (0.50 lp) y 10 feet (0.63 hp) 8 feet (0.50 hp) 6 feet (0.38 hp)
PRESTRESS LEVEL C L high seismicity medium seismicity
FUTURE WORK • model refinement • experimental verification • parametric investigation • strut-and-tie models • design recommendations