Lateral load test

When performing lateral load tests on deep foundations, it is

desirable to obtain horizontal displacement versus depth

profiles. These profiles can be used in conjunction with lateral

load versus displacement curves to calibrate lateral pile analysis

programs. In addition, the displacement versus depth curves

can be used to determine bending moment versus depth profiles.

Horizontal displacement versus depth profiles have typically

been determined using inclinometer probes or strings of

downhole inclinometers. Inclinometer probes require the user

to measure slope at 0.6 m intervals within a special grooved

pipe which is typically concreted into place within the pile. The

displacement of the pile must be held constant over a 15 to 20

minute period while the inclinometer measurements are made.

Strings of down hole inclinometers can also be installed at

various intervals within the inclinometer pipe. This option is

more expensive but allows measurements to be obtained

simultaneously and more quickly. Nevertheless, the

displacement of the foundation must be held relatively constant

for a several seconds so that the inclinometers can stabilize and

provide an accurate reading. This requirement usually

precludes their use for dynamic applications.