Geotechnical investigation and testing - Field testing - Part 6: Self boring pressuremeter test (ISO 22476-6:2018)

This document comprises requirements for investigations of soil and weak rock by pressuremeter tests with the self-boring pressuremeter (SBP) as part of the geotechnical investigation services according to EN 1997-1 and EN 1997-2.
Tests with the self-boring pressuremeter cover the measurement in situ of the deformation of soils and weak rocks by the expansion and contraction of a cylindrical flexible membrane under pressure.
The SBP is drilled into the ground using an integral self-boring head at its lower end in such a way that the probe replaces the material it removes so creating its own test hole and minimises the disturbance to the soil outside the instrument.
Pressure applied to, and the associated expansion of the probe are measured and recorded so as to obtain the stress-displacement relationship for the soil as tested.
During both boring and testing the data is recorded automatically.

Geotechnische Erkundung und Untersuchung - Felduntersuchungen - Teil 6: Selbstbohrender Pressiometerversuch (ISO 22476-6:2018)

Reconnaissance et essais géotechniques - Essais en place - Partie 6: Essai pressiométrique autoforé (ISO 22476-6:2018)

Le présent document spécifie les exigences relatives à l'appareillage, à l'exécution et au compte rendu des essais pressiométriques autoforés (PAF).
NOTE       Ce document satisfait aux exigences relatives aux essais pressiométriques autoforés dans le cadre des services de reconnaissance géotechnique selon les normes EN 1997‑1 et EN 1997‑2.
Les essais pressiométriques autoforés couvrent la mesure in situ la déformation d'un sol ou d'une roche tendre produite par l'expansion et la contraction d'une sonde cylindrique à membrane souple sous l'effet de la pression.

Geotehnično preiskovanje in preskušanje - Preskušanje na terenu - 6. del: Preskus s samouvrtanim presiometrom (ISO 22476-6:2018)

Ta dokument zajema zahteve za preiskovanje zemljine in šibkih kamnin s preskusi s samouvrtanim presiometrom (SBP) kot del storitev geotehničnega preiskovanja v skladu s standardoma EN 1997-1 in EN 1997-2. Preskusi s samouvrtanim presiometrom zajemajo meritve deformacije zemljin in šibkih kamnin na kraju samem s širjenjem in krčenjem valjaste fleksibilne membrane pod tlakom. Samouvrtani presiometer se uvrta v tla z vgrajeno samouvrtalno glavo na spodnjem koncu na ta način, da sonda zamenja material, ki ga odstrani, in tako ustvari lastno preskusno luknjo ter zmanjša spremembe konfiguracije zemljine zunaj instrumenta. Pritisk na sondo in povezano širjenje sonde se izmerita in zabeležita, da se pridobi razmerje med napetostjo ter izpodrivom zemljine med preskusom. Med vrtanjem in preskušanjem se podatki samodejno beležijo.

General Information

Status
Published
Public Enquiry End Date
14-Oct-2017
Publication Date
21-Nov-2018
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
05-Nov-2018
Due Date
10-Jan-2019
Completion Date
22-Nov-2018

Buy Standard

Standard
SIST EN ISO 22476-6:2018
English language
28 pages
sale 10% off
Preview
sale 10% off
Preview
e-Library read for
1 day

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 22476-6:2018
01-december-2018

*HRWHKQLþQRSUHLVNRYDQMHLQSUHVNXãDQMH3UHVNXãDQMHQDWHUHQXGHO3UHVNXV

VVDPRXYUWDQLPSUHVLRPHWURP ,62

Geotechnical investigation and testing - Field testing - Part 6: Self boring pressuremeter

test (ISO 22476-6:2018)
Geotechnische Erkundung und Untersuchung - Felduntersuchungen - Teil 6:
Selbstbohrender Pressiometerversuch (ISO 22476-6:2018)
Reconnaissance et essais géotechniques - Essais en place - Partie 6: Essai
pressiométrique autoforé (ISO 22476-6:2018)
Ta slovenski standard je istoveten z: EN ISO 22476-6:2018
ICS:
93.020 Zemeljska dela. Izkopavanja. Earthworks. Excavations.
Gradnja temeljev. Dela pod Foundation construction.
zemljo Underground works
SIST EN ISO 22476-6:2018 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN ISO 22476-6:2018
---------------------- Page: 2 ----------------------
SIST EN ISO 22476-6:2018
EN ISO 22476-6
EUROPEAN STANDARD
NORME EUROPÉENNE
October 2018
EUROPÄISCHE NORM
ICS 93.020
English Version
Geotechnical investigation and testing - Field testing - Part
6: Self boring pressuremeter test (ISO 22476-6:2018)

Reconnaissance et essais géotechniques - Essais en Geotechnische Erkundung und Untersuchung -

place - Partie 6: Essai pressiométrique autoforé (ISO Felduntersuchungen - Teil 6: Selbstbohrender

22476-6:2018) Pressiometerversuch (ISO 22476-6:2018)
This European Standard was approved by CEN on 1 October 2018.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this

European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references

concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN

member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by

translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management

Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,

Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2018 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 22476-6:2018 E

worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN ISO 22476-6:2018
EN ISO 22476-6:2018 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

---------------------- Page: 4 ----------------------
SIST EN ISO 22476-6:2018
EN ISO 22476-6:2018 (E)
European foreword

This document (EN ISO 22476-6:2018) has been prepared by Technical Committee ISO/TC 182

"Geotechnics" in collaboration with Technical Committee CEN/TC 341 “Geotechnical Investigation and

Testing” the secretariat of which is held by BSI.

This European Standard shall be given the status of a national standard, either by publication of an

identical text or by endorsement, at the latest by April 2019, and conflicting national standards shall be

withdrawn at the latest by April 2019.

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CEN shall not be held responsible for identifying any or all such patent rights.

According to the CEN-CENELEC Internal Regulations, the national standards organizations of the

following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,

Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia,

France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,

Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and the United Kingdom.
Endorsement notice

The text of ISO 22476-6:2018 has been approved by CEN as EN ISO 22476-6:2018 without any

modification.
---------------------- Page: 5 ----------------------
SIST EN ISO 22476-6:2018
---------------------- Page: 6 ----------------------
SIST EN ISO 22476-6:2018
INTERNATIONAL ISO
STANDARD 22476-6
First edition
2018-09
Geotechnical investigation and
testing — Field testing —
Part 6:
Self-boring pressuremeter test
Reconnaissance et essais géotechniques — Essais en place —
Partie 6: Essai pressiométrique autoforé
Reference number
ISO 22476-6:2018(E)
ISO 2018
---------------------- Page: 7 ----------------------
SIST EN ISO 22476-6:2018
ISO 22476-6:2018(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2018

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting

on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address

below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2018 – All rights reserved
---------------------- Page: 8 ----------------------
SIST EN ISO 22476-6:2018
ISO 22476-6:2018(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Symbols .......................................................................................................................................................................................................................... 2

5 Equipment ................................................................................................................................................................................................................... 3

5.1 General ........................................................................................................................................................................................................... 3

5.2 Self-boring pressuremeter probe ........................................................................................................................................... 5

5.3 Self-boring head ..................................................................................................................................................................................... 6

5.4 Pressure and displacement CU.................................................................................................................................................. 7

5.5 The connecting lines .......................................................................................................................................................................... 8

5.6 The injected fluid .................................................................................................................................................................................. 8

5.7 Means of measurement and control ..................................................................................................................................... 8

5.7.1 Data acquisition ................................................................................................................................................................ 8

5.7.2 Display of readings ......................................................................................................................................................... 8

6 Test procedure ........................................................................................................................................................................................................ 8

6.1 Selection of equipment and procedures ........................................................................................................................... 8

6.2 Calibration of the testing device and corrections of readings ........................................................................ 8

6.3 Probe placing ............................................................................................................................................................................................ 9

6.4 Relaxation .................................................................................................................................................................................................... 9

6.5 Loading program ................................................................................................................................................................................... 9

6.5.1 General...................................................................................................................................................................................... 9

6.5.2 End of test ...........................................................................................................................................................................11

6.6 Backfilling of the borehole .........................................................................................................................................................11

7 Test results — Interpretation of tests ..........................................................................................................................................11

8 Self-boring pressuremeter test report .......................................................................................................................................12

Annex A (normative) Calibration and corrections ..............................................................................................................................14

Annex B (informative) Placing the pressuremeter probe in the ground .....................................................................18

Annex C (normative) Accuracy.................................................................................................................................................................................19

Annex D (informative) Strain conversions ..................................................................................................................................................20

Bibliography .............................................................................................................................................................................................................................21

© ISO 2018 – All rights reserved iii
---------------------- Page: 9 ----------------------
SIST EN ISO 22476-6:2018
ISO 22476-6:2018(E)
Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work of preparing International Standards is normally carried out

through ISO technical committees. Each member body interested in a subject for which a technical

committee has been established has the right to be represented on that committee. International

organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.

ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of

electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www .iso .org/patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to the

World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following

URL: www .iso .org/iso/foreword .html.

This document was prepared by the European Committee for Standardization (CEN) Technical

Committee CEN/TC 341, Geotechnical investigation and testing, in collaboration with ISO Technical

Committee ISO/TC 182, Geotechnics, in accordance with the Agreement on technical cooperation

between ISO and CEN (Vienna Agreement).
A list of all parts in the ISO 22476 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www .iso .org/members .html.
iv © ISO 2018 – All rights reserved
---------------------- Page: 10 ----------------------
SIST EN ISO 22476-6:2018
INTERNATIONAL STANDARD ISO 22476-6:2018(E)
Geotechnical investigation and testing — Field testing —
Part 6:
Self-boring pressuremeter test
1 Scope

This document specifies the equipment requirements, execution of and reporting on self-boring

pressuremeter (SBP) tests.

NOTE This document fulfils the requirements for self-boring pressuremeter test as part of the geotechnical

investigation services according to EN 1997-1 and EN 1997-2.

Tests with the self-boring pressuremeter cover the measurement in situ of the deformation of soils and

weak rocks by the expansion and contraction of a cylindrical flexible membrane under pressure.

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments) applies.

ISO 10012, Measurement management systems — requirements for measurement processes and measuring

equipment

ISO 22475-1, Geotechnical investigation and testing — Sampling methods and groundwater

measurements — Part 1: Technical principles for execution
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
3.1
self-boring pressuremeter
SBP

equipment used to carry out a self-boring pressuremeter test (3.5), including the self-boring head (3.3)

used to drill the test pocket into the ground and the pressuremeter (3.2) used to carry out the expansion

Note 1 to entry: An SBP includes a probe composed of a self-boring head (3.3) and a pressuremeter (3.2) , an

hydraulic pump or other source of pressure, a test Control Unit (CU), pressure lines and wires to connect the

probe to the CU and a data logger which is either built into the CU or attached to it. The SBP is drilled into the

ground using the integral self-boring head at its lower end in such a way that the probe replaces the material it

removes, creating its own test hole, and minimises the disturbance to the soil outside the instrument.

3.2
pressuremeter

cylindrical expanding part of the equipment used to carry out a pressuremeter test excluding the means

necessary to place the pressuremeter probe into the ground
© ISO 2018 – All rights reserved 1
---------------------- Page: 11 ----------------------
SIST EN ISO 22476-6:2018
ISO 22476-6:2018(E)
3.3
self-boring head

part of the equipment used to drill the test pocket as the probe is advanced into the ground

Note 1 to entry: A self-boring head includes a boring tool: i.e. a rotating cutter or a high pressure jet arrangement,

housed in a cutting shoe attached at the probe end.
3.4
self-boring pressuremeter sounding

series of sequential operations necessary to perform self-boring pressuremeter testing at a given

location
Note 1 to entry: See 3.1.

EXAMPLE Pushing the self-boring pressuremeter, activating the self-boring head (see 5.3) and then

performing pressuremeter tests (see Clause 6).
3.5
self-boring pressuremeter test

process of expanding the self-boring pressuremeter probe so as to press the flexible membrane against

the borehole wall and so measure the associated displacement as a function of pressure and time

3.6
self-boring pressuremeter curve
graphical plot of pressure versus the measured displacement
3.7
depth of test

distance between the ground level and the centre of the expanding length of the self-boring pressuremeter

(3.1) measured along the borehole axis
Note 1 to entry: See Figure 1.
3.8
operator
qualified person who carries out the probe insertion and the test
4 Symbols
Symbol Description Unit
a pressure coefficient of the displacement mm.MPa
b membrane stiffness coefficient of the displacement MPa.mm
d corrected displacement at the borehole wall mm
d apparent displacement during the membrane compression calibration mm
d calculated cylinder expansion during the membrane compression calibration mm
d internal diameter of the calibration cylinder mm
d outside diameter of the cutting shoe mm
d displacement as read at the measuring unit mm
d initial outside diameter of the measuring cell mm
d outside diameter of the measuring cell mm
e thickness of the calibration cylinder mm
h distance between the cutting tool and the cutting edge mm
l length of calibration cylinder mm
l distance between the displacement transducer and the membrane mm
clamping ring
l expanding length mm
2 © ISO 2018 – All rights reserved
---------------------- Page: 12 ----------------------
SIST EN ISO 22476-6:2018
ISO 22476-6:2018(E)
Symbol Description Unit
p applied pressure after correction MPa
p pressure at the origin of the segment exhibiting the slope b MPa
p maximum applied pressure MPa
max
p pressure as read at the measuring unit MPa
r measured cavity radius mm
r initial radius mm
u pore pressure mm
t time s
V measured cavity volume mm
V initial volume mm
z test depth m
Δd diametral displacement of the borehole wall mm
Δp change of the applied pressure MPa
ε volumetric strain —
ε radial strain —
ν Poisson’s ratio —
5 Equipment
5.1 General
The self-boring pressuremeter equipment is shown in operation in Figure 1.
© ISO 2018 – All rights reserved 3
---------------------- Page: 13 ----------------------
SIST EN ISO 22476-6:2018
ISO 22476-6:2018(E)
Key
1 CU 9 hollow probe body
2 acquisition, display and storage of the data 10 self-boring head

3 depth measurement system 11 power supply for the cutter drive unit (if required)

4 connecting lines 12 cutter drive unit (if required)
5 handling rods 13 flushing or jetting fluid supply
6 cutter drive rods (if required) 14 pressure source for expansion
7 probe to rod coupling 15 ground
8 central measuring cell z test depth
Figure 1 — Schematic diagram of the self-boring pressuremeter equipment
The CU includes:
— equipment to pressurize and so to inflate the probe;

— a device which permits the direct reading and the automatic recording of the parameters to be

measured: time, pressure and volume or radial displacement.

The pressure applied to the membrane is measured by one or more electric transducers (see Figure 2).

The pressure transducers are located:
— above the ground surface, or
— inside the probe, less than 1 m above the centre of the expanding length.
4 © ISO 2018 – All rights reserved
---------------------- Page: 14 ----------------------
SIST EN ISO 22476-6:2018
ISO 22476-6:2018(E)

The displacement transducers for the membrane are located in the centre of the expanding length.

The outside diameter d of the self-boring pressuremeter when deflated shall normally be the same as

that of the cutting shoe d .

Use of an oversized cutting shoe shall be reported and taken into account during the analysis of the

results.

One or more pore pressure transducers can be located through the membrane in the centre of the

expanding length.

It is also necessary to have some means of measuring the depth of the test with appropriate accuracy.

5.2 Self-boring pressuremeter probe

The self-boring pressuremeter probe consists of a hollow core to allow the drill rods (if used) for self-

boring operation and carry flush returns to the surface. Flexible hoses and passages are used to inject

the proper fluids (gas or liquid) to inflate the central measuring cell whose expansion is monitored

by three or more electronic transducers or volume measurement (Figure 2). The probe is fitted with

a central cell membrane and may also be fitted with a Chinese lantern protective device to prevent

damage from sharp inclusions in the soil. The probe shall be capable of a volumetric expansion of at

least 25 % of the initial volume V .

The central measuring cell, with an outside diameter d and a length I , can expand radially in a

s s

borehole and apply a uniform pressure to the borehole wall. This central measuring cell shall have a

[7][10]

minimum slenderness I /d of 4,0 . This cell is inflated by injecting a liquid which is assumed to be

s s0
incompressible or by gas pressure.
The probe also includes:

a) The core on its outside curved surface usually bears a pattern of grooves which distribute the

liquid in the central cell under the flexible membrane. Over the core is fitted the membrane and the

Chinese lantern protective cover. The top of the core is threaded and couples to the string of rods

handling the probe from ground level.

b) The central cell membrane isolates the fluid from the space under the Chinese lantern

protective cover.
c) Fluid lines connect the probe to the pressure and displacement CU.

d) The expansion of the membrane can be monitored by electric transducers. At least three

displacement transducers should be available to monitor the mean surface but also any non-

circular deformation of the membrane.

e) The pore pressure in the ground can be monitored by one or more electric transducers placed

approximately at mid-height of the expanding length.
© ISO 2018 – All rights reserved 5
---------------------- Page: 15 ----------------------
SIST EN ISO 22476-6:2018
ISO 22476-6:2018(E)
Key
1 hollow probe body 7 displacement transducers
2 membrane 8 pressure transducer
3 cutting shoe 9 membrane clamping ring
4 cutting tool 10 electronic signal conditioning
5 pressure line 11 setting and cutter drive rods
6 one pore pressure transducer
Figure 2 — Example of a self-boring pressuremeter probe
5.3 Self-boring head

The self-boring head is the lower part of the probe with an outside diameter d . It has a sharp cutting

edge with the taper on the inside and as the probe is steadily and slowly advanced into the ground by

pushing, the soil that enters it is cut up and removed to the surface through the interior of the probe

body by the action of either (Figure 3):
— a rotating cutter,
— an upward pressurised water jet, or
— a lateral pressurised water jet.

The rotating cutter can be in a shape of a rock roller bit, a full face cutter, a flat blade or a stirring

paddle (disc).
Use of percussion on rotating cutter shall be reported.
6 © ISO 2018 – All rights reserved
---------------------- Page: 16 ----------------------
SIST EN ISO 22476-6:2018
ISO 22476-6:2018(E)

To identify the influence of tool wear on SBP tests, it may be appropriate to check and report the status

of the initial and final wear of the tool and/or shoe. For this purpose, the dimensions of the tools at

the beginning and end of the drilling can be measured, where feasible, and reported (according to

ISO 22476-15). The change or replacement of any equipment shall be reported as well.

Key
a. rotating cutter
b. upward pressurised water jets
c. lateral pressurised water jets
Figure 3 — Self-boring head

The distance h between the cutting tool or the nozzle and the cutting edge is a function of the nature of

the soil (Figure 4) as defined in Annex B.
Figure 4 — Distance between the cutting tool and the cutting edge

When the ground becomes stiffer a lower value of h is used (see Annex B). For hard soils and soft rocks,

a negative value of h may be used, hence the rotating tool protubing from the cutting edge. The tool

shall not be entirely outside of the cutting shoe.
NOTE The influence of ratio h/d is highlighted in References [7],[8] and[9].
5.4 Pressure and displacement CU

The pressure and displacement CU permits the reading of liquid or gas pressure and displacement as

a function of time and controls the probe expansion and contraction. The pressure may be controlled

manually or automatically.
© ISO 2018 – All rights reserved 7
---------------------- Page: 17 ----------------------
SIST EN ISO 22476-6:2018
ISO 22476-6:2018(E)
The pressurizing device shall permit:
— reaching a pressure p at least equal to 4 MPa;
— keeping a constant pressure in the measuring cell;
— imposing cycles of pressure and displacement at several constant rates.
5.5 The connecting lines

The flexible lines connect the pressure and displacement CU to the probe. They transmit the pressurized

liquid or the gas to the measuring cell and may be parallel or coaxial.

The signal cable connects the transducers of the instrument to the data logging system.

5.6 The injected fluid

The fluid injected into the measuring cell may be gas, water, oil or a liquid of similar viscosity. It shall

not freeze in the conditions of use.
5.7 Means of measurement and control
5.7.1 Data acquisition

The data logging system shall be so designed and constructed as to ensure that all the data required for

a complete analysis of the test is fully and permanently recorded at the time of the test.

Measurements may also be made periodically during probe insertion while boring.

The accuracy of the measuring systems time, pressure, volume and displacement shall be as specified

in Annex C.
5.7.2 Display of readings

At the site the pressure and volume CU shall give a simultaneous and immediate display of the following

readings: pressure of the fluid injected into the measuring cell, radial displacement or volume of the

fluid injected, pore pressure (if applicable), and jetting pressure (if applicable).

6 Test procedure
6.1 Selection of equipment and procedures

The membrane of the probe and the self-boring head used in a self-boring sounding shall be selected

according to the expected ground conditions. The probe is then linked to the CU through the connecting

lines and cables and the whole system is filled with the working fluid.
6.2 Calibration of the testing device and corrections of readings

Before testing, the equipment shall have been calibrated. Copies of the calibration documents shall be

available at the job site. The calibrations shall be done according to ISO 10012 on:

— the displacement measuring systems, and
— the pressure measuring systems.

Corrections as described in Annex A shall be performed taking into consideration the maximum

pressure and displacement expected during the test.

If any part of the system is repaired or exchanged, the calibration shall be verified.

8 © ISO 2018 – All rights reserved
---------------------- Page: 18 ----------------------
SIST EN ISO 22476-6:2018
ISO 22476-6:2018(E)

The calibrations shall also be verified on completion of a self-boring pressuremeter testing programme.

6.3 Probe placing

The choice of cutting shoe and cutting tool or nozzle should meet the specifications in Annex B. Pressure

of the flushing fluid and the force needed to push the probe shall be controlled during boring to ensure

that there is no clogging inside the probe. Comparison between the pressure
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.