ASTM D8381/D8381M-21

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D8381/D8381M − 21
Standard Test Methods for
Measuring the Depth of Deep Foundations by Parallel
Seismic Logging
This standard is issued under the fixed designation D8381/D8381M; the number immediately following the designation indicates the
year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last
reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope Combining values from the two systems may result in non-
conformance with the standard.
1.1 The test Methods described in this standard are used to
measure the depth of vertical deep foundation elements includ- 1.7 All observed and calculated values shall conform to the
ing micropiles, driven piles (prefabricated or cast in-situ), guidelines for significant digits and rounding established in
bored piles, secant or tangent pile walls, caissons, barrettes, Practice D6026.
diaphragm walls and sheet pile walls. It is applicable where the
1.8 The methods used to specify how data are collected,
topofthesaidfoundationelement(inthefollowingalsonamed
recorded and calculated in this standard are regarded as the
“pile”) cannot be exposed for testing and other testing methods
industry standard. In addition, they are representative of the
such as ASTM D5882 or D6760 cannot be used.
significant digits that should generally be retained. The meth-
1.2 This standard provides minimum requirements for mea- ods used do not consider material variation, purpose for
suring the depth of deep foundations. Plans, specifications, obtaining the data, special-purpose studies or any consider-
and/or provisions may provide additional requirements and ations for the user’s objectives; and it is common practice to
methods as needed to satisfy the objectives of a particular test increase or reduce significant digits of reported data to be
program. commensuratewiththeseconsiderations.Itisbeyondthescope
of this standard to consider significant digits used in analysis.
1.3 This standard provides the following test methods:
1.3.1 Method “A” using a vertical access tube adjacent to 1.9 This standard offers an organized collection of informa-
the deep foundation. tion or a series of options and does not recommend a specific
1.3.2 Method “B” using a seismic cone inserted into the course of action. This document cannot replace education or
ground adjacent to the deep foundation. experienceandshouldbeusedinconjunctionwithprofessional
judgment. Not all aspects of this standard may be applicable
1.4 ApparatiandMethodshereindesignated“optional”may
under all circumstances. This ASTM standard is not intended
produce different a different kind of test results or additional
to represent or replace the standard of care by which the
information and may be used only when approved by the
adequacy of a given professional service must be judged, nor
engineer responsible for the test.
should this document be applied without consideration of a
1.5 The text of this standard references notes and footnotes
project’smanyuniqueaspects.Theword“Standard”inthetitle
that provide explanatory material. These notes and footnotes
of this document only means that the document has been
(excluding those in tables and figures) shall not be considered
approved through the ASTM consensus process.
as requirements of the standard.
1.10 This standard does not purport to address all of the
1.6 Units—The values stated in either SI units or inch-
safety concerns, if any, associated with its use. It is the
pound units are to be regarded separately as standard. The
responsibility of the user of this standard to establish appro-
values stated in each system may not be exact equivalents;
priate safety, health, and environmental practices and deter-
therefore,eachsystemshallbeusedindependentlyoftheother.
mine the applicability of regulatory limitations prior to use.
1.11 This international standard was developed in accor-
dance with internationally recognized principles on standard-
These test methods are under the jurisdiction ofASTM Committee D18 on Soil
ization established in the Decision on Principles for the
and Rock and are the direct responsibility of Subcommittee D18.11 on Deep
Development of International Standards, Guides and Recom-
Foundations.
mendations issued by the World Trade Organization Technical
Current edition approved Nov. 1, 2021. Published November 2021. DOI:
10.1520/D8381_D8381M-21 Barriers to Trade (TBT) Committee.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D8381/D8381M − 21
2. Referenced Documents 4.1.2 The method can also be performed using a seismic
2 sensor instead of a hydrophone. In this case , water is not
2.1 ASTM Standards:
required and the sensor is clamped to its sidewall by an
D653 Terminology Relating to Soil, Rock, and Contained
appropriate device. The sensor might provide additional infor-
Fluids
mation due to registration of several wave types and
D3740 Practice for Minimum Requirements for Agencies
components, but has no advantage to a hydrophone for the
Engaged in Testing and/or Inspection of Soil and Rock as
Method described above. Chains of hydrophones or seismic
Used in Engineering Design and Construction
sensors (a set of sensors mounted in fixed intervals along a
D4428/D4428M Test Methods for Crosshole Seismic Test-
multicore cable and used for simultaneous recording at several
ing
depths) can be used to speed up the investigation. In the
D5882 Test Method for Low Strain Impact Integrity Testing
following, just the term probe is used for both devices.
of Deep Foundations
D6026 Practice for Using Significant Digits and Data Re-
NOTE 1—When striking the superstructure is undesirable because of the
potential for physical damage (such as decorative or historic finishes), or
cords in Geotechnical Data
it appears that there is no connection between the superstructure and
D6760 Test Method for Integrity Testing of Concrete Deep
supporting pile, the side of the pile may be exposed by digging an access
Foundations by Ultrasonic Crosshole Testing
pit. As the test quality may improve by applying axial blows, this can be
D7400/D7400M Test Methods for Downhole Seismic Test-
achieved by cutting a notch in the side of the pile or attaching a sturdy
ing bracket to it.
D8232 Test Procedures for Measuring the Inclination of
4.2 Method B:
Deep Foundations
4.2.1 In this method, a seismic cone, conforming to the
2.2 Other Standards:
requirements of Test Method D7400/D7400M, is inserted into
AFNOR NF P94-160-3 Auscultation d’un élément de
the ground proximate to the deep foundation, stopping after
fondation, partie 3: Méthode sismique parallèle
each depth interval. At each stop the pile or superstructure
above the deep foundation are hit at least once with a
3. Terminology
trigger-equipped hammer. A portable digital recording device
3.1 Definitions:
and a (separate or integrated) display device that are connected
3.1.1 For definitions of common technical terms used in this
to the seismic cone via a data cable or a wireless connection,
standard, refer to Terminology D653.
record the output trace for each blow and then plot the results
against the respective depth.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 depth interval, n—the vertical spacing between two
NOTE 2—Method B may be inapplicable for testing the depth of
stops. foundations that penetrate into bedrock (such as rock sockets) or other
hard or very dense strata due to inability to push the seismic cone to the
3.2.2 seismic sensor, n—an instrument to measure the
required depth.
ground motion when it is shaken by a perturbation, including
geophones or accelerometers. 5. Significance and Use
3.2.3 stop, n—the level at which the hydrophone or seismic
5.1 It is often necessary to determine the depth of deep
sensor is stopped for taking a measurement.
foundation elements supporting existing structures, such as
buildings and bridges, for which neither drawings nor as-built
3.2.4 trace, n—the time history of the seismic sensor output
records are available. Such situations occur when the founda-
at any given depth.
tion loads have to be increased or when it is intended to
4. Summary of Test Method excavate near, or even under, the structure.When the top of the
foundation is inaccessible, as is the case with underwater
4.1 Method A:
bridge piers, the Parallel Seismic method can be used to
4.1.1 In this method, a vertical access tube is installed in a
determine the deep foundations’ depth. The method is also
borehole drilled proximate to the deep foundation and filled
applicable in cases where the foundation top can be reached,
with water. A hydrophone, connected to a depth measuring
but the foundation element is not testable by the Low Strain
device, is lowered into the access tube. After a brief pause at
Impact Integrity Testing Method (ASTM D5882) due to the
each stop to stabilize the hydrophone reading, the pile or
foundation type (such as diaphragm and secant-pile walls,
superstructure are hit at least once with a trigger-equipped
H-piles and sheet piles) or excessive foundation slenderness.
hammer.Aportable digital recording device and a (separate or
integrated) display device that are connected to the trigger, 5.2 Agencies that meet the criteria of Practice D3740 are
depth meter and the hydrophone via data cables or wireless
generally considered capable of competent and objective
connections, record and plot the hydrophone output trace for testing and inspection. However, users of this standard are
each blow against the respective depth below the reference
cautioned that compliance with Practice D3740 does not in
level. itself assure reliable results since the proper conduct and
evaluation of parallel seismic tests requires training, special
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Niederleithinger, E., “Improvement and Extension of the Parallel Seismic
Standards volume information, refer to the standard’s Document Summary page on Method for Foundation Depth Measurement,” Soils and Foundations, Vol. 52 Nr. 6,
the ASTM website. 2012, pp. 1093-1101.
D8381/D8381M − 21
knowledge and experience. A suitably qualified engineer shall 6.2.1 CPT (Cone Penetration Testing) Rig, equipped with a
plan and supervise the acquisition of field data and the seismic cone attached to the end of rigid rods. The CPT rig
design should allow positioning close enough to the tested
interpretation of the test results.
element.
6.2.2 Data Logger, equipped with an accurate clock and
6. Apparatus
abletosimultaneouslyrecordthedepthoftheseismicconeand
6.1 Method A:
the pulse reaching the seismic cone.
6.1.1 Pressure-sensitive probe (hydrophone or seismic
6.2.3 Control Box, equipped with an accurate clock and
sensor), pressure-rated to withstand penetration depths pre- recording the time of each trigger pulse.
scribed in 9.1.1 and 9.2.2, respectively. 6.2.4 Digital recording and display device.
6.2.5 Triggering Hand-Held Hammer,—equipped with a
6.1.2 Signal Transmission Cable (optional)—The cable
piezo shock switch. A typical schematic arrangement of the
shall be sufficiently robust to carry the probe and abrasion
testing apparatus is illustrated in Fig. 2.
resistant to allow repeated field use and maintain flexibility in
the range of expected temperatures. The cable itself, as well as
7. Hazards
all connectors, shall be waterproof to at least 150 % of the
7.1 The test is often carried out over water or on construc-
maximum testing depth. Alternatively, a wireless connection
tion sites with traffic of mechanical equipment such as tractors
between the probe and the data recording and display unit may
or drilling rigs, and used heavy, mobile equipment, potentially
be established.
overhead. This standard does not purport to address all the
6.1.3 Depth Measuring Device—The cable shall be marked
safety concerns, if any, associated with its use. It is the
at regular intervals to assess depth of probe. Alternatively, a
responsibility of the user of this standard to establish appro-
pulley over which the cable is deployed may be instrumented
priate safety, health and environmental practices and determine
with a depth-encoding device to monitor the depth to the
the applicability of regulatory limitations prior to use.
location of the probe throughout the test. The design of the
7.2 Before penetrating the ground to prepare for the test the
pulley and cable reel shall be such that cable slippage shall not
engineer in charge shall verify that no buried utilities will be
occur. Alternatively, a flexible tape measure may be affixed to
affected during the process.
the transducer/cable such that it measures the transducer
centerline depth but does not interfere with signal transmission 8. Calibration
to the transducer. Depth data may also be obtained from any
8.1 The depth encoder wheel (if used) shall be field-
source as long as it meets the requirements of 8.1.
calibrated at least once every six months to an accuracy of 1 %
6.1.4 Triggering is done with a hand-held hammer,
of the maximum testing depth or 0.1 m [4 in.], whichever is
equipped with a piezo shock switch or instrumented hammer larger, according to the manufacturer’s instructions.
head that can record the impact signal.Alternatively, a suitable
8.2 The whole system shall be regularly calibrated follow-
receiver (such as an accelerometer) may be mounted to the
ing the manufacturer’s instruction and checked for functi
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