Acigs newsletter 201305

Newsletter May 2013 Edition

AUS TRALASI AN CHA P TE R

OF TH E IN TERN A TI ON AL

GE OS YN THE TI CS SO C IETY

Corporate IGS Members:

ACIGS in GeoAsia 2012

Invited Lecturers

Malek Bouazza the President,

and Mike Sadlier the Vice Pres-

ident of the Australasian Chap-

ter of the International Geosyn-

thetics Society (ACIGS), were

invited to give separate lectures

at GeoAsia 2012. They were

also invited members in the

conference Technical Commit-

tee.

Case Studies

ACIGS was asked to prepare

some case histories to be pre-

sented at GeoAsia 2012 in

Bangkok, Thailand in Decem-

ber 2012. After announcing this opportunity to its mem-

bers, ACIGS received a paper provided by Amir

Shahkolahi and Jason Crase from Global Synthetics

with the title of ‘Application of Geogrids and Geocompo-

sites in Designing Working Platforms on Cohesive Sub-

grades; Case study: Harvey Norman Bulky Goods De-

velopment Australia’

The paper was accepted by the Technical Committee

and presented by Jason Crase at the conference. The

full paper is attached to this newsletter for public use

with the Author’s permission to the ACIGS. Of course

any further use will require mentioning the paper as a

reference.

Join us on LinkedIn www.linkedin.com (search ACIGS in ‘Groups’)

Geosynthetics Asia 2012 5th Asian Regional

Conference on Geosynthetics

Bangkok, Thailand, 13-15 December 2012 The 5th Asian Regional Conference on Geosyn-

thetics (GA2012) with the theme of Geosynthetics

for Sustainable Adaptation to Climate Change

was successfully held at Centara Grand Lardprao

Hotel in Bangkok, Thailand last 13th to 15th De-

cember 2012.

GA2012 was organised by IGS Thailand Chapter,

Asian Centre for Soil Improvement (ACSI) and

Suranaree University of Technology (SUT) under

the auspices of the International Geosynthetics

Society (IGS). Prof. Dennes T. Bergado and Prof.

Suksun Horpibulsuk served as Chairman and Co-

Chairman of the Organising Committee.

Mike Sadlier

Ribbon Cutting Ceremony during the opening of the exhibition event

The Australasian Chapter of the International Geosynthet-

ics Society (ACIGS) started its activity in 2002. Since then,

several activities such as technical seminars have been or-

ganised by the ACIGS. During these years, the number of the

ACIGS members has increased steadily to reach 68 members

in 2013.

By being an ACIGS member, one will become an International

Geosynthetics Society (IGS) member and get access to all

membership benefits such as free access to Geosynthetics

Journals, Presentations, Lectures, etc. More benefits are pre-

sented in the membership form.

At the same time, ACIGS members will be able to attend

ACIGS meetings and benefit from a registration discount in

ACIGS seminars. The chart above shows the ACIGS mem-

bership increase. It indicates there has been a significant im-

provement (about 240%) in the number of ACIGS individual

members from 2012 to 2013.

More information about IGS and its Chapters around the world

can be found here: www.geosyntheticssociety.org

Membership Growth

ACIGS Individual Memberships

IGS Council Elections Results: Term 2012 to 2016

The IGS, in accordance with its bylaws, held a

mid-term election in 2012. IGS Members

elected eight Council Members from an excel-

lent field of 12 candidates. Each of the elected

members will serve a four-year term, begin-

ning on 11 December 2012.

The successful candidates in the 2012 elec-

tion are (alphabetically by family name):

Dennes T. Bergado, Thailand (2nd term)

Erol Güler, Turkey

Warren Hornsey, Australia

Jiro Kuwano, Japan (2nd term)

Nicola Moraci, Italy

Victor Pimentel, Brazil (2nd term)

Boyd Ramsey, USA

Kent von Maubeuge, Germany

These 8 candidates join the existing council

and elected officers for a total of 22 current

members.

ACIGS Breakfast Gather ing

ACIGS organised a gathering during GeoAsia2012 for ACIGS members to have breakfast and get familiar with each

other as well as IGS Officers and other international geosynthetic experts. The gathering was held on 14th December

2012 at the conference venue. More than 15 members and non-members discussed different ideas and shared their

experiences about geosynthetic products and projects. This was also a good opportunity for ACIGS members to have

a short chat with IGS Officers and international experts in a quiet and private environment.

Contact Us:

Email: [email protected]

Post: C/- Amir Shahkolahi,

44 Telford Street, Virginia QLD 4014

Phone: Amir on 07 3865 7000 .

LinkedIn www.linkedin.com (search ACIGS in ‘Groups’)

3

Seminar Basal Reinforced Embankments

International Guest Speaker Chris Lawson

Sponsors:

Chris Lawson Seminar Basal Reinforced Embankments

Chris Lawson, Managing Director of

TenCate Geosynthetics Asia-Pacific

based in Hong Kong, has worked in

the field of geosynthetics for 30 years

covering Australia, Europe, North

America and Asia. Chris has been in-

volved in developing the geosynthetics

Standards and Codes of Practice, and

is author of over 50 technical papers

on the subject of geosynthetics.

During May/June 2013, Chris will be

touring Australia and New Zealand

presenting along with local Engineers

at 1-day seminars hosted by ACIGS.

Topics include:

Reinforced soil utilising geosyn-

thetics

Geosynthetics for reinforced soil

Design approach to basal rein-

forced embankments

Basal reinforced embankments on

soft foundations

Basal reinforced piled embank-

ments

Basal reinforced embankments

spanning voids

ACIGS is inviting members and non-

members to attend their local 1-day

seminar, being an excellent opportuni-

ty to meet and network with new and

long standing ACIGS peers.

The cost is $100.00AUD. As a special

offer, for non-members the registration

fee includes membership to join the

ACIGS; And for existing members the

registration fee will be considered as a

membership renewal payment.

Sponsorship opportunities available

Please send your interest to

[email protected]

AU ST RAL ASI AN C H APT ER

OF T H E I NT ERN AT I ON AL

GEO SYNT H ET IC S SOCI ET Y

Name:

Position:

Company:

Phone:

Email:

Membership No:

Cheque: Payable to “Geosynthetics Interest Group”

EFT: A/C name: Geosynthetics Interest Group

BSB: 063 142 Account No: 10213604

Credit Card: Mastercard Visa

Account number:

Expiry date:

Name on card:

Authorised signature:

Sydney - 28 May 124 Pacific Hwy, St Leonards NSW

Auckland - 31 May L2, Nielsen Centre, 129 Hurstmere Rd, Auckland NZ

Brisbane - 04 June 147 Coronation Dr, Milton QLD

Adelaide - 12 June 121 King William St, Adelaide SA

Perth - 14 June L3, 1 Havelock St, West Perth WA

Time: 9am - 5pm (morning refreshments and light lunch provided)

Yes, I would like to become an ACIGS member

Please return your form to: Email: [email protected] Fax: (07) 3865 4444

Post: C/- Amir Shahkolahi, 44 Telford St, Virginia QLD 4014

Corporate members:

Venue sponsors:

4

10th International Conference on Geosynthetics 21 - 25 September 2014 Berlin, Germany

Cal l for Abstracts

CALL FOR PAPERS

The deadline for abstract submission is 15 May 2013

For conference themes and submission details visit http://www.10icg-berlin.com

Visit the 10 ICG website http://www.10icg-berlin.com

The German Geotechnical Society (DGGT) and the Interna-

tional Geosyn-thetics Society (IGS) German Chapter, as a

special group within the DGGT, cordially invite you to partici-

pate in the 10th International Conference on Geo-synthetics

(10ICG) in 2014 in Berlin, Germany.

The conference will be held from 21 to 25 September 2014 in

direct connection with the 33rd Baugrundtagung (German

Soil Mechanics Conference) of DGGT (23 to 26 September

2014). As the Baugrundtagung expects 1200 participants,

great synergy and interaction is expected between these

events, especially in the co-organized, co-located exhibition.

The overlapping of lectures from both events will also attract

many additional experts from the geotechnique and geosyn-

thetics professions. The official language of 10ICG will be

English.

Venue

The 10ICG will be held in the south-eastern of Berlin at the

ESTREL convention centre. ESTREL offers about 50 rooms

for lectures and meetings, integrated exhibition halls and a 4-

star hotel. Travelling time from there to the centre of Berlin is

about 20 minutes.

Berlin

Berlin is the capital city of Germany and offers a tremendous

number of interesting cultural events, museums and sightsee-

ing attractions directly in the city. The 10ICG programme for

accompanying persons will cover guided city tours, visits to

museums and galleries.

10ICG Conference Themes

• Green Engineering, Sustainability and Durability with Geo-

synthetics

• Use of Geosynthetics for Renewable Energy

• Mining, Waste Management, Contaminated Sites and Envi-

ronmental Protection

• Roads, Railways and Other Transportation Applications

• Reinforcement in Walls, Slopes, Embankments and Base

Courses

• Flood Control, Levee and Canals, Dams, Reservoirs and

Other Hydraulic Applications

• Drainage and Filtration Properties of Geosynthetics

• Geomembrane and Geosynthetic Clay Liner Barrier Sys-

tems

• Case Histories and Innovative Uses of Geosynthetics

• Quality Control, Quality Assurance and Accreditation

• On-site Installation Technologies and Monitoring Programs

• Soil-Geosynthetic Interaction and Large-Scale Performance

Testing

• Design Approaches

• Regulations and Recommendations

• Looking to the Future with New Geosynthetic Products

Call for Paper

You are invited to send in your abstracts for the conference

dealing with the use of geosynthetics in the topics above

since January 2013. The deadline for the submission is 31

July 2013. The postponement of the abstract submission

deadline is due to avoid direct overlap of the submission peri-

ods with the new established GeoAfrica 2013 conference.

Please find all necessary information in time on the confer-

ence webpage.

Exhibition

The 5000 m² technical exhibition space is directly connected

to the conference rooms, being located half-way be-tween the

hotel and lecture rooms and accessed without having to leave

the centre. The exhibtion space will be used both by 10ICG

and the Baugrundtagung event. The reservation period for

the exhibition will be open through the webpage in June

2013. IGS Corporate Members will have a pre-registration

due the regulations of IGS.

For more information

Please vistit the website that will be updated in due time:

www.10icg-berlin.com

For further information please contact: Gerhard Bräu

([email protected]); or Dr. Kirsten Laackmann

([email protected])

Extended until 21 July 2013!

http://www.10icg-berlin.com

mailto:[email protected]

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market. We specialise in the technical marketing and distribution of geosynthetic products, and proudly manufacture a

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in-house at our customer oriented Geosynthetic Centre of Excellence or through us funding Australian research

students.

Through our range of activities, we provide high-quality, engineered solutions to geotechnical problems. Our use of

highly skilled people, equipped with the leading geosynthetic brands and supported by superior technical tools will

ensure our customers have access to world-class geosynthetic solutions for their infrastructure projects.

Quality, Support and Expertise – the essence of Geofabrics.

GEOSYNTHETICS ASIA 2012

5th Asian Regional Conference on Geosynthetics

13 to 16 December 2012 | Bangkok, Thailand

1

APPLICATION OF GEOGRIDS AND GEOCOMPOSITES IN

DESIGNING WORKING PLATFORMS ON COHESIVE SUBGRADES;

CASE STUDY: HARVEY NORMAN BULKY GOODS DEVELOPMENT,

AUSTRALIA

Amir Shahkolahi1, Jason Crase

2

1Technical Consultant and Applications Engineer/Global Synthetics; Tel: +61-7 3865 7000; Fax: +61-7 3865

4444; Email: [email protected], 2Regional Manager/Global Synthetics; Tel: +61-7 3865 7000; Fax: +61-7 3865 4444; Email:

[email protected]

ABSTRACT

In the construction of heavily trafficked areas such as working platforms, a stable subgrade with sufficient

bearing capacity is required. Economical and environmental advantages of construction methods with

geosynthetics, especially on soft soils are already well known. Soil masses that need to be excavated, transported

and installed can be dramatically reduced by the inclusion of geosynthetics. The best example is the

improvement of soft subgrades with geogrids or geocomposite products. In this paper, the general design

procedure is presented for working platforms using geosynthetics according to Building Research Establishment

(BRE). A project constructed in SE Queensland Australia using a unique geocomposite is then discussed in

further detail. This geocomposite which is a combination of a geogrid with a high secant strength and an integral

nonwoven geotextile, encapsulated between the cross laid welded bars, was successfully installed directly on top

of the subgrade with CBR value as low as 1%, providing not only improvement of the subgrade bearing

capacity, but also a positive separation and filtration layer between fine subgrade materials and imported

granular platform materials. A 350 mm granular platform was then installed on top of the Combigrid®. This

method could make the construction of thin granular platform layer on the soft subgrade possible, reducing

construction costs and construction time for the client and the contractor. Also, the reduced requirement for

imported quarried materials in the working platform had significant additional environmental benefits.

Keywords: working platform, geogrid, geocomposite, cohesive subgrade

INTRODUCTION

The expression, working platform is, restricted to

ground-supported working platforms, for tracked

plant, constructed of granular material. Working

platforms are critical for plant stability, and safety is

a vital issue. Most working platforms perform well,

but overturning of rigs has occurred more frequently

than it should. Experience has shown that it is far

more likely that rigs will overturn owing to localised

problems rather than to a generally inadequate

platform thickness across the whole site. Localised

weaknesses can be associated with the existence of

‘soft spots’ in the subgrade, under the platform, or

with weak areas within the platform formed by

inadequate backfilling of holes that have been

excavated by other contractors working on the site.

Similarly, ‘hard spots’ caused by old foundations or

basements can cause difficulties. Where a weak

subgrade is particularly soft or loose, some form of

stabilisation or ground treatment may be considered

to improve the properties of the ground (BRE 2004).

For a working platform, the soil and groundwater

conditions in the upper 2 m are particularly

important. Where there is a granular subgrade, the

presence of a water-table close to the ground surface

will have a critical effect in reducing bearing

resistance (BRE 2004).

In some situations it may be economic to

incorporate geosynthetics to strengthen the working

platform as an alternative to using a greater

thickness of platform material.

In this paper, the design procedure for working

platforms using geosynthetics has been reviewed

according to the Building Research Establishment

(BRE) design guide published in the United

Kingdom (UK) and was commissioned by the UK

Federation of Piling Specialists, together with a

recently constructed project is presented as a case

history.

APPLICATION OF GEOSYNTHETICS IN

WORKING PLATFORMS

Often the required bearing capacity on subgrades

cannot be achieved, such that additional measures

have to be undertaken. As an economic solution to






2

improve the subgrade strength, the installation of

geosynthetics for reinforcement, filtration and

separation may be successfully adopted.

Geosynthetics are generally placed between the

subgrade and the material forming the working

platform. Some designs may require additional

geosynthetic layers to be placed within, but

alternatively may be placed within the platform .to

provide additional support on particularly soft soils

or where the equipment working on the platform is

large.

On cohesive formations, upward migration of

fine material into the working platform may cause it

to degrade, particularly in wet conditions. A granular

filter layer or a geotextile can be used to minimise

the migration of fine material from the subgrade into

the platform material. Geotextiles are normally used

to separate a granular platform from a cohesive

subgrade and to act as a filter (BRE 2004).

Geogrids are normally used to strengthen the

platform. Vehicular loads applied to the road surface

create a lateral spreading motion of the aggregate.

Tensile lateral strains are created at the interface

subgrade/geogrid as the aggregate moves down and

sideways due to the applied load (BRE 2004).

In addition to general strengthening over the

whole area of the platform, localised strengthening

and additional maintenance may be needed at

particular locations. It is important to distinguish

geosynthetics which have been incorporated into the

platform to provide tensile strength from those

intended as separation layers, unless a combined

geosynthetic is used. Owing to the ductile nature of

polymeric reinforcement, ultimate tensile capacity

may occur at very high strain beyond the

serviceability requirements of the reinforced soil,

and design should be based on the strength at a

specified small strain or by applying a factor to the

ultimate strength. Also the likelihood of damage to

geogrids during installation should be taken into

account (BRE 2004).

DESIGNING WORKING PLATFORMS WITH

GEOSYNTHETICS

If the existing soil is not sufficiently strong to

carry the loads of the piling rig, a design of the

geogrid reinforced working platform as an

economic alternative is required to distribute the

loads to an acceptable rate for the in-situ

subgrade. The platform design method follows a

logical sequence from assessment of plant loading

through to platform thickness (BRE 2004).

The bearing resistance Rd of the cohesive in-situ

subgrade underneath the tracks when a load is

applied directly to the subgrade surface can be

calculated as follows (BRE 2004):

uccd cNs=R (1)

where sc is the shape factor, cu is the subgrade

undrained shear strength and Nc is the bearing

capacity factor. The bearing capacity factor for a

cohesive subgrade is Nc = (2 + π), and where the

load is applied at ground surface over a rectangular

area of dimensions W and L, the shape factor is

given by (BS EN 1997-1:2004):

0.2[W/L] + 1 =sc (2)

Where a load is applied to a working platform

with relatively shallow thickness which has been

placed on the weak subgrade, the simple approach

for calculating the bearing resistance of this two-soil

system can be based on the analysis of punching

failure. In this analysis the bearing resistance R is

considered to be the sum of the shear required to

punch through a vertical plane in the granular

platform material and the bearing capacity of the

subgrade (Fig. 1) (BRE 2004).

Fig. 1 Punching failure mechanism

Using the simplified analysis developed by

Meyerhof and his co-workers for a footing punching

through a dense sand layer overlying soft clay, the

following expression is obtained for the bearing

resistance of a platform on a cohesive subgrade

(Meyerhof 1974):

pp

2

pccu s tanK /W)D( +sNc = R (3)

where D is the thickness of the platform material, W

is the track width of the plant, Nc is the bearing

capacity factor for a cohesive subgrade, Kptanδ is the

punching shearing resistance coefficient of the

granular platform material and can be determined

from Fig. 2 as a function of the angle of the shearing




3

resistance of the material (φ’), γp is the bulk unit

weight of the platform material and sc and sp are the

shape factors, which are functions of W and L and:

[W/L] + 1 =sp (4)

Where geosynthetic reinforcement is

incorporated at the base of the working platform to

take tensile loads, the required thickness of platform

can be reduced. The design tensile strength of the

reinforcement (Td) should be evaluated by applying

a minimum factor of 2 to the ultimate tensile

strength (Tult) of the reinforcement so that:

Fig. 2 Design values of Kptanδ (BRE 2004)

/2T =T ultd (5)

Where the reinforcement is not stiff, a higher

factor or the strength at 5% strain should be used

(BRE 2004).

The bearing resistance provided by the

reinforcement has to be assessed and it is proposed

that this is calculated in a simplified way based on

the punching failure mechanism, such that the

additional bearing resistance is calculated as 2Td/W.

For a platform on a cohesive subgrade we will have

(BRE 2004):

/W2T +s tanK /W)D( +sNc = R dpp

2

pccu

(6)

The interaction of the base course material

with the geogrid results in a measurably higher

internal friction angle at low lateral compression like

in road constructions (Ziegler and Ruiken 2010).

The tests have shown that internal friction angles

higher than δ = 60° are detectable for the compound

construction (Ziegler and Ruiken 2010). Of course it

should be considered that the punching shear failure

mechanism is only applicable where the working

platform is significantly stronger than the underlying

subgrade. Also the routine design calculation

method based on punching shear is not appropriate

where (D/W) >1.5 and Slopes are greater than 1 in

10 or for ground conditions 20 kPa < cu < 80 kPa

(BRE 2004).

Routine working platform design calculations

with geosynthetics have the following stages:

determine ground conditions, determine design load

cases according to characteristic loads from EN

996:1996 and design load factors (BRE 2004),

derive bearing capacity and shape factors and

punching shear coefficient, check support of

platform material alone, determine required

thickness of platform using geosynthetic

reinforcement and final evaluation of results (BRE

2004). As a final check, the design thickness of

platform should satisfy the following conditions

(BRE 2004): ignoring the effect of the

reinforcement, both load cases q1d and q2d are < Rd

where:

1k1d 1.25q = q (7)

2k2d 1.05q = q (8)

ppd

2

pccudd s tanK )/WD( +sNc = R (9)

where q1d is the design load case 1 (standing,

travelling), q2d is the load case 2 (handling,

penetrating, extracting) and q1k and q2k are

characteristic load cases 1 and 2. If these two

requirements are not met, the thickness of platform

should be increased until they are. As a limitation,

the minimum platform thickness should be the lesser

of 0.5W or 300 mm (BRE 2004).

CASE HISTORY

Project and Problem Description

In 2011, it was planned to build granular piling

rig access platforms to facilitate the installation of

piles for support of the new Harvey Norman bulky

goods project in Maroochydore in Australia to

increase the low subgrade strength and to provide

sufficient bearing capacity for the imposed loads of

the cranes.

After site investigations, the consultant

confirmed that the current condition of the site

surface would not be satisfactory for the safe

operation of the proposed precast piling rig imposed

load of 280 kN/m3. It was also advised that the grey




4

clay exposed on the surface of the site had been

badly affected through saturation as a result of the

2010 local flooding. Subsequent continual wet

weather was not allowing the perched groundwater

to drain away, leaving the platform saturated. Three

boreholes were drilled at the site in August 2008

finding a silty sand at the surface in BH1 located

toward the northern end, a clayey silt (low plasticity

with a trace of sand) in BH2, and low plasticity silty

clay in BH3 at the southern end of the site. These

surface soils alone were not capable of supporting

the required 280kPa bearing capacity required for

the pile rig. A further constraint was that the

platform thickness was limited to 350 mm above the

existing subgrade elevation to avoid interference

with the intended levels of the proposed basement

car parking concrete slab on ground.

Geosynthetic Improvement Solution Using

geogrid/geocomposite

The main purpose of the geogrid reinforced

piling platform is to reduce the imposed bearing

pressures of the piling rig to acceptable rates for the

given bearing capacity of the in-situ subgrade. As

the subgrade was a weak subgrade and the thickness

of the platform was limited, the geosynthetic

reinforced platform on existing subgrade was chosen

as the economic alternative solution for the initial

design for providing suitable (i.e. safe and stable)

access for the piling rig, which was 200mm

excavation and 500mm thick platform installation

consisting of good quality unbound pavement

gravel.

With reference to the given information, a

subgrade CBR value of min. 1% (equal to cu > 30

kN/m2) has to be considered for the bearing capacity

of the in-situ soft subgrade. The design was focused

on the specific machine type with the total weight of

77200 kg. The design of the reinforced working

platform was carried out with full consideration of

BRE design manual and design principles defined

in DIN 4017:2006 to reach a sufficiently high

safety factor against bearing failure.

The bearing resistance Rd of the cohesive in-situ

subgrade underneath the tracks can be calculated as

follows (BRE 2004):

2

uccd kN/m 154.2 = cNs = R (10)

with sc equal to 1 (safer value), cu equal to 30 kN/m2

and Nc equal to 5.14 for φ ≥ 0°. The fill material for

the working platform was a well graded crushed

aggregate with an assessed internal angle of friction

of approx. 40°. After consideration of the potentially

variable conditions on site (compaction, grain size

distribution, internal friction angle of fill material)

a relatively conservative internal friction angle

for the compound construction (geogrid + fill

material) of δ = 50° was considered on the safe side

for this design.

In case that a h = 350 mm thick geogrid

reinforced working platform is used, the area of

influence on the in- situ subgrade can be calculated

as follows:

))(h tan 2 +(W ))(h tan 2 + (L 2 =A (11)

A = 22.83 m² with:

L = Length of crawler track, here: 5.75 m

W = Width of crawler track, here: 0.90 m

Considering the required bearing capacity to be

achieved according to the design brief was 280

kN/m2, the net bearing pressure qres imposed on the

subgrade at under side of the 350mm thick geogrid

reinforced crane working pad platform was

calculated as:

kN/m² 63.47 =LW/A kN/m 280 = q 2

res (12)

According to DIN 4017:2006, the safety factor

against bearing failure is taken to η = 2.0. In the

particular case of the above mentioned project, the

safety factor η against bearing failure can be

calculated to:

result. q / q = (13)

Then η = 154.2 kN/m² / 63.47 kN/m² = 2.42. The

calculation shows that the solution adopted satisfies

the minimum required safety factor for bearing

failure of η = 2.0 according to DIN 4017:2006.

To prevent fines from migrating into the base

course a filtration and separation nonwoven

geotextile underneath the geogrid is

recommended. For the selection of the geogrid

reinforcement to be used underneath working

platforms, Rüegger et al (2003) defines an

extensional stiffness of 400 kN/m or 8 kN/m

tensile strength at 2 % strain respectively.

Geogrid/Geocomposite Selection

Upon final approval, some 50000 m2 of

Combigrid® 40/40 Q1 151 GRK 3 was installed

successfully on site under the crane platform directly




5

on the soft subgrade, to improve the subgrade

bearing capacity as well as to prevent fines from

migrating into the platform materials. The cross

section is shown in Fig. 3.

Fig. 3 Reinforced working platform

This geocomposite has a min. tensile strength of 16

kN/m at 2% strain which is much more than 8 kN/m

and fulfills the recommendation from Rüegger et al

(2003). This product consists of a Secugrid®

geogrid as the reinforcement component; with a

needle-punched nonwoven geotextile firmly welded

between the reinforcement bars, for soil

stabilisation, separation and filtration. This

geocomposite combines all of these functions into

one single product. It offers the advantages of two

materials with the simplicity of installing a single

product. It is also extremely quick and easy to

install, thus reducing installation costs considerably.

The appropriate strength of the geogrid was selected

according to the stress strain properties required

above and the subgrade bearing capacity. Figs. 4 and

5 show some installation pictures.

Fig. 5 Installation and overlaps

ACKNOWLEDGEMENT

The authors sincerely appreciate the assistance of

colleagues, especially J. Klompmaker and C. Psiorz

from BBG GmbH & Co. KG, and the support from

NAUE GmbH & Co. KG. The authors would also

like to acknowledge Martin Smith for the final

review and the assistance of Chris Carey of ADCO

Constructions Pty Ltd in correspondence and liaison

with the client regarding the development of this

adopted solution.

REFERENCES

British Research Establishment-BRE (2004).

Working platforms for tracked plant: Good

practice guide to the design, installation,

maintenance and repair of ground-supported

working platforms. Report BR470.

BS EN 1997-1 (2004). Eurocode 7: Geotechnical

design – Part 1: General rules.

DIN 4017 (2006). Calculation of design bearing

capacity of soil beneath shallow foundations.

Meyerhof G.G. (1974). Ultimate bearing capacity of

footings on sand layer overlying clay Canadian

Geotechnical Journal, vol. 11, no. 2: 223–-229.

Rüegger R. and Hufenus R. (2003). Building with

Geosynthetics – A Handbook for Geosynthetic

Users. Swiss Association for Geosynthetics.

Ziegler M. and Ruiken A. (2010). Examination of

the Performance of Geogrids with wide-scaled

Triaxial Tests. Project Number 0703, RWTH,

Aachen.

Fig. 4 Installation

C/o Peter Tzelepis

83-93 Canterbury Road Braeside VIC 3195

25 February 2013

MEMBERSHIP FEES FOR AUSTRALIAN CHAPTER OF IGS (ACIGS):

Fee for year 2013 A$ 75.00 per member The cheque is to be made out to Geosynthetics Interest Group. Please note that we are not registered for GST, hence there is no GST component in this fee. Please sign a copy of this invoice and return it with your payment, as a confirmation that you

accept the rules and By-Laws of the ACIGS.

Peter Tzelepis Treasurer

Members Details:

Name: ___________________________________________________________________

Company: ________________________________________________________________

Position: _________________________________________________________________

Email: ___________________________________ Phone No. _______________________

Mode of payment: Cheque enclosed: Payable to “Geosynthetics Interest Group”

Credit card (circle one): Mastercard Visa Bankcard

Account Number: ________________________________

Expiry date: ________________________________ Name on card: ________________________________ Authorised Signature: ________________________________

EFT: Account Name: Geosynthetics Interest Group

BSB: 063 142

Account No.: 10213604

RETURN EMAIL: [email protected]

RETURN FAX No: 07 3865 4444

Australasian Chapter of International Geosynthetic Society

ABN : 27 845 329 614

to collect and disseminate knowledge on all matters relevant to geotextiles, geomembranes and related

products by promoting the development of seminars, conferences, publications, etc.

to promote advancement of the state of the art of geotextiles, geomembranes and related products and of

their applications by encouraging, through its members, the harmonization of test methods, equipment and

criteria , etc.

to improve communication and understanding regarding such products between designers, manufacturers

and users and especially between the geosynthetic manufacturing and engineering communities

The International Geosynthetics Society (IGS) is a non-profit organization which was founded in Paris, on 10

November 1983, by a group of geotechnical engineers and textile specialists. The society brings together

individual and corporate members from all parts of the world, who are involved in the design, manufacture,

sale, use or testing of geotextiles, geomembranes, related products and associated technologies, or who teach

or conduct research about such products.

The IGS has a constantly growing General Membership, currently over 2800 members. In addition, there

are over 230 Student Members worldwide. There are 34 national or regional Chapters of the IGS repre-

senting 90% of the membership. Our growing Corporate Membership has exceeded 137 members from 69

countries.

The IGS is managed by 5 elected officers and 10-16 elected council members— a maximum of 5 co-opted

council members may also serve on the council. Contact information for council and officers is

available on the IGS website under Directories at www.geosyntheticssociety.org.

The IGS Aims

promotes the dissemination of technical information on geosynthetics through its two official journals

Geotextiles & Geomembranes and Geosynthetics International

provides a forum for the exchange of ideas through communications at IGS Conferences and IGS

supported events on local, national, regional and international levels

through work in its Educational and Technical committees, publishes documents which provide guidance to

the users of geosynthetics

through work in its Technical Committees assists in the editing of documents from other agencies,

associations or regulators

publishes The IGS News three times annually

hosts a publicly available web site for members and non-members to search many of the educational

documents created by the IGS

offers multiple awards including the IGS Award for excellence in achievement

A comprehensive listing of the IGS’ 25 years of achievement can be found on the IGS Web Site

on the page titled Milestones

In Order to Achieve These Aims the IGS:

By becoming a member of the IGS you will:

help support the aims of the IGS

contribute to the advancement of the art and science of geotextiles, geomembranes and re-

lated products and of their applications

be exposed to a forum where designers, manufacturers and users are exchanging new ideas

and developing new contacts

become increasingly informed, involved and influential in the field of geotextiles, geomem-

branes, related products and associated technologies

on-line access to the IGS Membership Directory which is updated in real-time, with full

addresses, telephone, email and fax numbers of all members

complete access to the on-line version of Journal Geosynthetics International.

complete access to the on-line version of the Journal Geotextiles & Geomembranes

electronic access to the IGS NEWS, published three times annually

on-line access to the 19 IGS Mini Lecture Series for the use of the membership

Opportunity to join open committees to contribute to topics of common interest

on-line access to the growing library of multilingual IGS Educational Leaflets

discount rates

on any document published by the IGS

at all international, regional or national conferences organized by the IGS or under

its auspices

preferential treatment at conferences organized by the IGS or under its auspices

eligibility for various IGS awards

IGS membership card and IGS lapel pin

Benefits to All Members

Chapters of the IGS

Contact information for all Chapters of the IGS may be found on our website:

Argentina

Indonesia Poland

Australasian Italy Portugal

Belgium Japan Romania

Brazil Korea Russia

Chile Mexico Slovakia

China Netherlands South Africa

Czech North American Spain

Finland Norway Thailand

France Pakistan Turkey

Germany Peru United Kingdom

Greece Philippines West Pacific Regional

India

Acigs newsletter 201305

Documents

Transcript of Acigs newsletter 201305