Bent 2 – Static Testing Program and Instrumentation

Hugo Escobar, Ali Morovat, and Sharon Wood

Department of Civil, Architectural and Environmental Engineering

University of Texas at Austin

Testing Program – Spring 2006

• Overview―Free-vibration response (modal hammer tests)―Forced-vibration response (T-Rex)―Static lateral forces (T-Rex and Liquidator)

• Additional Instrumentation for Static Tests―String potentiometers (lateral deflections)―Linear potentiometers (vertical deformation at

ends of columns)

Static Testing Program

• Both static and dynamic tests were conducted to evaluate how the frequency response and damping of the bent varied with the level of damage in the soil, foundation, and structure

• Lateral forces were applied using the winches attached to the front of T-Rex and Liquidator

• Due to the location of Bent 2 relative to the property line, lateral forces could only be applied in one direction.

Test Designation

• Each test is numbered from 001 to 043.• Between tests 001 and 029, the following

sequence was used:―Free-vibration tests―Forced-vibration tests―Static lateral forces

• Between tests 030 and 043, the following sequence was used:―Free-vibration tests―Static lateral forces

Liquidator was used toapply the static lateralforces in these tests.

Both Liquidator and T-Rexwere used to apply the static lateral forces in these tests.

Free-Vibration Test

Impact Locations for Modal Hammer Tests

ProjectNorth

Location B

Location A

2S

2N

yz

y

x

Forced-Vibration Test

Forced-Vibration Test

~ 24 ft

Static Lateral Forces(Tests 007 – 029)

Liquidator

~ 50 ft

Project North

2S 2NLoad Cell

Reference Frame

Static Lateral Forces(Tests 007 – 029)

Load Cell

Static Lateral Forces(Tests 032 – 043)

Static Lateral Forces(Tests 032 – 043)

Project North

2S 2N

Load CellReference Frame

Liquidator

T-Rex

~50 ft

Load Cell

External Reference Frame

12 in. (1.0 ft)

24 in. (2.0 ft)

45 in. (3.75 ft)

Base (0.0 ft)

3.75W 3.75E

2.0

0N 0S

1.0

3.75W

3.75E

2.0

0N

0S

1.0

String Potentiometers

3.75W

3.75E

2.0

0N

1.0

Linear Potentiometers

Column 2N Column 2S

NorthTop

NorthBottom

SouthTop

SouthBottom

NorthTop

NorthBottom

SouthTop

SouthBottom

Column 2SSouth, Top

Column 2SSouth, Bottom

Column 2NNorth, Top

Column 2NNorth, Bottom

Column 2SNorth, Bottom