Geotechnical Engineering Circular No. 9 Design, Analysis, and Testing of Laterally Loaded Deep Foundations that Support Transportation Facilities

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(Alternate Table XXXX-1)
Table XXXX – 1
(Proof test and test to failure)
Load Increment
Percentage of
Design Load (%)
Load (kips)
Hold Time
(Minutes)
1 0 To be calculated based on maximum test load)
--
2 25 10 3
50 10 4
75 15 5
100 20 6
125 20 7
150 20 8
170 20 9
180 20 10 190 20 11 200 60 12 150 10 13 100 10 14 50 10 15 0
10 16 50 10 17 100 10 18 150 10 19 200 10 20 210 15 21 220 15 22 230 15 23 240 15 24 250 15 25 Etc. to a maximum of
1” of movement
30 26 75% of maximum
10 27 50% of maximum
10 28 25% of maximum
10 29 0
--
(Commentary: Two sample load increments tables are provided above it is only intended to include one
in the test specification.
The first table includes the loading sequence per ASTM D Procedure A as indicated. This is a design
verification test sequence that will test the pileup to 200 percent of the design load. The second table
includes the proof test sequence followed by a sequence to test the pile to a maximum of 1” deflection.
The intent in the second procedure is to test the pile until the maximum deflection is met rather than
simply 200 percent of the design load. The maximum deflection can be modified for the test. Other load
sequences are presented in the ASTM specification and the table above can be modified and load
sequences added, as appropriate to satisfy the test objectives.
The specification can present a table of the load sequence, as indicated above, or can simply refer to the
designated load test sequence in the ASTM specification)

262 3.13 Readings of all instrumentation shall be performed for each load increment. Record readings of time, load, and movement immediately before and after the application or removal of each load increment. Additional readings shall be performed at 5 minute and at 15 minute intervals while the test load is applied and at 15 and 30 minute intervals after the test load is removed.
(Commentary: The frequency of readings can be adjusted to fit the test objectives. Some readings, such
as gauge readings on the displacement gauges, are easy to take, and can be done electronically with
LVDT gauges and data recorders. Others, such as inclinometer readings, are time consuming and would
only be expected to be performed once per load increment. Frequent readings during load increments,
especially high load increments, will help detect creep or the onset of failure)
3.14 If pile failure occurs before one inch of movement, a reading shall betaken immediately before removing the first load increment.
3.15 Following completion of the lateral load test and recording of all data readings, the Contractor shall perform site restoration at the test location in accordance with the requirements of the Contract Documents.

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