S PECIFICATION D&C B30

EXCAVATION AND BACKFILL FOR

BRIDGEWORKS
Copyright – Transport for NSW
IC-DC-B30

VERSION FOR: Coffs Harbour Bypass

DATE: October 2021

Edition 2 / Revision 2 TRANSPORT FOR NSW

June 2020
Excavation and Backfill for Bridgeworks D&C B30

CONTENTS
CLAUSE PAGE
FOREWORD .........................................................................................................................................II
TfNSW Copyright and Use of this Document ............................................................................ii
Base Specification.....................................................................................................................ii

1 GENERAL .................................................................................................................................. 1
1.1 Scope ......................................................................................................................... 1
1.2 Structure of the Specification...................................................................................... 1
1.3 Definitions ................................................................................................................. 2

2 SAFETY AND ENVIRONMENTAL PROTECTION............................................................................. 2

2.1 Work Health and Safety ............................................................................................. 2
2.2 Environmental Protection ........................................................................................... 2

3 COFFERDAMS AND SHORING ..................................................................................................... 2

4 EXCAVATION ............................................................................................................................ 3
4.1 General ...................................................................................................................... 3
4.2 Excavation of Stream Channel.................................................................................... 3
4.3 Excavation for Construction of Structures................................................................... 4
4.4 Inspection of Foundation Material .............................................................................. 4

5 MASS CONCRETE BLINDING LAYER .......................................................................................... 5

6 BACKFILLING AGAINST STRUCTURES ........................................................................................ 5

6.1 General ...................................................................................................................... 5
6.2 Fill and Drainage Material .......................................................................................... 5
6.3 Age of Structure Before Backfilling............................................................................ 7
6.4 Placing and Compaction ............................................................................................. 7
6.5 Drainage Zone Behind Earth Retaining Structures ...................................................... 9
6.6 Disposal of Surplus Excavated Material...................................................................... 9

ANNEXURES B30/A TO B30/B – (NOT USED)..................................................................................... 10

ANNEXURE B30/C – SCHEDULES OF HOLD POINTS AND IDENTIFIED RECORDS .................................. 10

C1 Schedule of Hold Points ........................................................................................... 10
C2 Schedule of Identified Records ................................................................................. 10

ANNEXURE B30/D – PLANNING DOCUMENTS .................................................................................... 10

ANNEXURE B30/E – EXCAVATION, SELECT FILL AND DRAINAGE ZONE VOLUMES FOR MEASUREMENT
AND PAYMENT PURPOSES........................................................................................................ 12

ANNEXURES B30/F TO B30/K – (NOT USED) ..................................................................................... 17

ANNEXURE B30/L – MINIMUM FREQUENCY OF TESTING .................................................................. 17

ANNEXURE B30/M – REFERENCED DOCUMENTS ............................................................................... 18

LAST PAGE OF THIS DOCUMENT IS ..................................................................................................... 18

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D&C B30 Excavation and Backfill for Bridgeworks

FOREWORD

TFNSW COPYRIGHT AND USE OF THIS DOCUMENT

Copyright in this document belongs to Transport for NSW.

When this document forms part of a deed

This document should be read with all the documents forming the Project Deed.

When this document does not form part of a deed

This copy is not a controlled document. Observe the Notice that appears on the first page of the copy
controlled by TfNSW. A full copy of the latest version of the document is available on the TfNSW
Internet website: http://www.rms.nsw.gov.au/business-industry/partners-
suppliers/specifications/index.html

BASE SPECIFICATION
This document is based on Specification TfNSW B30 Edition 4 Revision 2.

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TfNSW SPECIFICATION D&C B30

EXCAVATION AND BACKFILL FOR BRIDGEWORKS

1 GENERAL

1.1 SCOPE
This Specification sets out the excavation and backfilling requirements associated with bridgeworks,
including earth retaining structures. It also sets out the requirements for cofferdams and shoring, and
mass concrete blinding layers.

Backfilling includes both backfilling of excavations up to the adjacent surface level, and backfilling to
the levels shown on the Design Documentation drawings, such as that behind bridge abutments and
earth retaining structures.

This Specification does not cover:

(a) backfilling from the natural surface level up to the underside of the sill beam at “spill-through”
bridge abutments – refer to Specification TfNSW D&C R44 for the relevant requirements;
(b) backfilling against and over culverts or box section underpasses – refer to Specification TfNSW
D&C R11 for the relevant requirements;
(c) backfilling for reinforced soil walls – refer to Specification TfNSW D&C R58 for the relevant
requirements.

1.2 STRUCTURE OF THE SPECIFICATION

This Specification includes a series of annexures that detail additional requirements.

1.2.1 (Not Used)

1.2.2 (Not Used)

1.2.3 Schedules of HOLD POINTS and Identified Records

The schedules in Annexure B30/C list the HOLD POINTS that must be observed. Refer to
Specification TfNSW D&C Q6 for the definition of HOLD POINTS.

The records listed in Annexure B30/C are Identified Records for the purposes of TfNSW D&C Q6.

1.2.4 Planning Documents

The PROJECT QUALITY PLAN must include each of the documents and requirements listed in
Annexure B30/D and must be implemented.

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1.2.5 Frequency of Testing

The Inspection and Test Plan must nominate the proposed frequency of testing to verify conformity of
the item, which must not be less than the frequency specified in Annexure B30/L. Where a minimum
frequency is not specified, nominate an appropriate frequency. Frequency of testing must conform to
the requirements of TfNSW D&C Q6.

1.2.6 Referenced Documents

Standards, specifications and test methods are referred to in abbreviated form (e.g. AS 1234). For
convenience, the full titles are given in Annexure B30/M.

1.3 DEFINITIONS
The terms “you” and “your” mean “the Contractor” and “the Contractor’s” respectively.

The following definitions apply to this Specification:

Contaminated Material classified as Restricted, Hazardous or Special Waste in accordance with

material EPA Waste Classification Guidelines.

Earth retaining Structures which are designed and constructed to retain earth. They include
structures retaining walls and bridge abutments (including the sill beam of spill-through
abutments).

Frame Structures with their members joined together by moment resisting connections,
structures such as integral and semi-integral bridges.

Select Fill Fill material of specified quality placed against or adjacent to structures. This
material is different from Selected Material (refer TfNSW D&C R44 for definition
of Selected Material).

2 SAFETY AND ENVIRONMENTAL PROTECTION

2.1 WORK HEALTH AND SAFETY

Implement work health and safety measures, including preparation of Safe Work Method Statements,
in accordance with Specification TfNSW D&C G22.

2.2 ENVIRONMENTAL PROTECTION

Implement appropriate environmental control measures in accordance with Specifications TfNSW
D&C G36 and D&C G38.

3 COFFERDAMS AND SHORING

Cofferdams must be constructed sufficiently watertight to prevent water seepage through the sides
during concreting, which can cause damage to the freshly placed concrete.

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Position the toe of the cofferdam sufficiently below the level of the bottom of the excavation, to avoid
piping at the bottom of the excavation from water seepage.

Provide adequate bracing to the cofferdams. The construction of the cofferdam must be such that
removal of the cofferdam will not damage the concrete structure.

Provide sufficient clearance within the cofferdam for construction and inspection of the exterior
surfaces of the formwork and for pumping out water both inside and outside the forms as required.

HOLD POINT
Process Held: Construction of cofferdams and/or shoring.

Submission Details: At least 5 working days prior to the proposed date for commencement of
construction, submit details of the cofferdams and/or shoring with details of
clearances provided, together with a statement by a Chartered Professional
Engineer experienced in this type of work, certifying the design.

Release of Hold Point: The Nominated Authority will consider the submitted documents prior to
authorising the release of the Hold Point.

Do not incorporate material used in the construction of the cofferdam or shoring within the concrete of
the finished structure, unless shown otherwise on the Design Documentation drawings.

Remove any cofferdams and shoring, including temporary piles, to a minimum of 0.5 m below natural
or finished surface, whichever is lower.

4 EXCAVATION

4.1 GENERAL
4.1.1 Survey Marks

During excavation and backfilling, do not disturb any survey bench marks, survey or level peg, plug,
pipe or marking. Comply with the requirements of Specification TfNSW D&C G71 on the care,
protection and preservation of survey control marks.

4.1.2 No Blasting

Do not use blasting in excavation for foundation members.

4.1.3 Contaminated Material

If contaminated material is encountered during excavation, notify the Principal immediately and deal
with the contaminated material in accordance with TfNSW D&C R44.

4.2 EXCAVATION OF STREAM CHANNEL

Where excavation of a stream channel is required, the excavation must extend to join the existing
stream bed in such a manner as to allow the smooth flow of water past the structure.

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4.3 EXCAVATION FOR CONSTRUCTION OF STRUCTURES

4.3.1 General

Excavate for construction of structures to the depth and profile shown on the Design Documentation
drawings. The Principal may require excavation to a different level from that shown on the Design
Documentation drawings.

Avoid disturbing the material below the required excavation level shown on the Design
Documentation drawings.

Remove all loose material from within the excavation before placing concrete.

4.3.2 Foundations on Rock

For foundations bearing on rock, thoroughly clean out any minor fissures in the rock and refill the
fissures with concrete, mortar or grout. Wet the rock surface prior to placing concrete.

Fill any over-excavation in rock with concrete of the same quality as that of the overlying concrete
structure.

4.3.3 Foundations on Earth

For foundations bearing on earth, backfill any over-excavation under the foundation member with
Select Fill complying with Clause 6.2.2, or concrete of the same quality as the overlying concrete
structure.

4.3.4 Excavation for Anchor Beams

Excavate for anchor beams, anchor blocks, and other similar members in a manner such that concrete
for the member placed within the excavation is in direct contact with the sides of the excavation.

If side forms are used, fill the space between the concrete member and the sides of the excavation
remaining when forms are removed with concrete of the same quality as that of the member.

4.4 INSPECTION OF FOUNDATION MATERIAL

Prior to placing concrete for the mass concrete blinding layer, present the excavated foundation area
for inspection by the Geotechnical Design Representative.

HOLD POINT
Process Held: Placing of concrete for mass concrete blinding layer for each foundation
member (except foundation members supported by piles).

Submission Details: Conformity records for levels and dimensions of excavation, for each
foundation member.

Release of Hold Point: The Nominated Authority will inspect the foundation material, and may
direct further excavation, prior to authorising the release of the Hold Point.

Where further excavation is required, the above Hold Point will again apply after the completion of the
excavation to the new levels or new dimensions.

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5 MASS CONCRETE BLINDING LAYER

Where shown on the Design Documentation drawings, place unreinforced mass concrete as a blinding
layer over the earth foundation material. Do not place concrete in the presence of surface or seepage
water.

The concrete for the blinding layer must be of the same quality as that of the overlying concrete
structure, unless shown otherwise on the Design Documentation drawings.

The mass concrete layer must be brought to a level finish unless shown otherwise on the Design
Documentation drawings and allowed to harden sufficiently before any subsequent operation over it
can take place, to avoid damage to the layer.

6 BACKFILLING AGAINST STRUCTURES

6.1 GENERAL

6.1.1 Extent

Backfill against structures to the details shown on the Design Documentation drawings.

6.1.2 Remove Foreign Material

Prior to backfilling, remove all foreign material such as waste concrete and timber from within the
excavation.

6.2 FILL AND DRAINAGE MATERIAL

6.2.1 General

Fill material for backfilling and granular drainage material must be free of timber and rubbish.

Where these materials are imported, provide the Principal with details of the proposed source
locations, quantities and types of material before the imported material is delivered to site.

6.2.2 Chemical Properties

The chemical properties of placed Select Fill, earth fill and drainage material must conform to
Table B30.1.

Table B30.1 – Chemical Properties of Fill and Drainage Material

Property Test Method Requirement

pH TfNSW T123 ≥ 5.5
Sulfates (expressed as SO4) TfNSW T1011 ≤ 1000 mg/L
Chlorides TfNSW T1010 ≤ 200 mg/L

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6.2.3 Select Fill

Select Fill must conform to the requirements shown in Table B30.2, and must be capable of achieving
the relative compaction specified in Clause 6.4.

Table B30.2 – Select Fill Material Properties

Property Test Method Requirement

(1)
Particle size distribution: TfNSW T106, T107
Percentage passing AS Sieve (by mass)
53 mm 100%
37.5 mm > 60%
2.36 mm < 50%
75 µm < 15%
(2) (1)
Coefficient of uniformity TfNSW T106, T107 ≥5
Plasticity Index TfNSW T108, T109 ≤ 15
Notes:
(1)
After pretreatment in accordance with Test Method TfNSW T102.
(2)
Coefficient of uniformity = D60/D10, where D60 and D10 are the equivalent sieve sizes in mm which 60%
and 10% of the Select Fill passes respectively, as interpolated from particle size distribution curve.

6.2.4 Earth Fill

Earth fill must conform to the requirements shown in Table B30.3, and must be capable of achieving
the relative compaction specified in Clause 6.4.

Table B30.3 – Earth Fill Material Properties

Property Test Method Requirement

Maximum particle dimension TfNSW T280 200 mm
Particle size distribution: TfNSW T106
Percentage passing AS Sieve (by mass)
37.5 mm > 60%
Coefficient of uniformity (1) TfNSW T106, T107 ≥5
Notes:
(1)
Coefficient of uniformity = D60/D10, where D60 and D10 are the equivalent sieve sizes in mm which 60%
and 10% of the Earth Fill passes respectively, as interpolated from particle size distribution curve.

6.2.5 Drainage Zone Material

Drainage zone material must be clean, graded, hard and durable, of either crushed stone or river
gravel, conforming to the requirements shown in Table B30.4:

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Table B30.4 – Drainage Zone Material Properties

Property Test Method Requirement

Particle size distribution: TfNSW T106
Percentage passing As Sieve (by mass)
53 mm 100%
9.5 mm < 5%

6.2.6 Corrugated Perforated Plastic Subsurface Drainage Pipe

Corrugated perforated plastic subsurface drainage pipe must comply with Specification
TfNSW D&C 3552.

6.3 AGE OF STRUCTURE BEFORE BACKFILLING

Unless specified otherwise on the Design Documentation drawings, carry out backfilling only at the
following times:

(a) Against concrete members other than those in items (b) or (c)
Do not carry out backfilling until at least 7 days has elapsed after concrete placement, or at least
75% of the specified minimum 28 day concrete compressive strength of the member has been
achieved, whichever is earlier.

(b) Against concrete earth retaining structures (e.g. cantilever retaining walls and conventional
bridge abutments)
Do not carry out backfilling until at least 100% of the specified minimum 28 day concrete
compressive strength of the structure has been achieved, but in any case not earlier than 7 days
after concrete placement.

(c) Against concrete frame structures (e.g. integral and semi-integral bridge abutments)
In addition to the requirements of item (b) above, do not carry out backfilling until the
compressive strength of the concrete in the bridge deck (or horizontal connecting slab) has
reached at least 75% of the specified minimum 28 day concrete compressive strength.

6.4 PLACING AND COMPACTION

6.4.1 Field Moisture Content

Unless specified otherwise or accepted by the Principal, the field moisture content of the Select Fill
and earth fill at the time of placing must be between 60 to 90% of the optimum moisture content.

Determine the field moisture content in accordance with Test Methods TfNSW T120, T121 or T180.
Only use T121 and T180 where results have previously been checked against those of T120 for the
range of materials being compacted, using Test Method TfNSW T2105.

6.4.2 Layer Thickness and Relative Compaction

Place Select Fill and earth fill in layers of (compacted) thickness not exceeding that shown in Table
B30.5, and compact to the relative compaction requirements shown in Table B30.5.

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Conformity of a Lot is achieved if the characteristic value of relative compaction of that Lot is not less
than the lower limit specified in Table B30.5.

Table B30.5 – Fill Materials, Layer Thickness and Compaction

Maximum Relative
Fill Type Location Layer Compaction
Thickness (2) (3)

Select Fill Below foundations on earth where over-excavation has 150 mm (4) 102%
occurred (refer Clause 4.3.3).
Select Fill Behind abutments and retaining walls (1) within a 150 mm (4) 98%
distance of H/2 from edge of base slab, where H is
distance between the base of the footing and the top of
the wall.
Earth Fill All other locations. 300 mm 98%
Notes:
(1)
“Behind … walls” refers to the backfilled side of the walls.
(2)
Layer thickness after compaction.
(3)
Lower limit of characteristic value of relative compaction.
(4)
May be increased to 200 mm away from abutments or retaining walls where machines heavier than one tonne
are permitted in compaction.

6.4.3 Determination of Field Density and Relative Compaction

Determine the field (insitu) density using either Test Methods TfNSW T173 using a nuclear gauge,
TfNSW T119 using the sand replacement method, or TfNSW T165 using the fixed volume extractive
method. The situations where these test methods are applicable are shown in Table B30.6.

Table B30.6 – Applicable Test Methods for Determining Field Density and Relative Compaction

Fill Material Properties Test Method / Actions

≤ 20% by mass retained on 37.5 mm AS sieve Either T173 (nuclear gauge) or T119 (sand
replacement method)
> 20%, ≤ 40% by mass retained on 37.5 mm AS sieve T119 (sand replacement method) (1)
> 40% by mass retained on 37.5 mm AS sieve Report only % by mass of oversize material (2)
Fine to medium grained sand, including single size T165 (fixed volume extractive method)
material or gap graded material
Notes:
(1)
If % by mass retained on 37.5 mm AS sieve is between 20% and 40%, do not use the nuclear gauge method.
(2)
If % by mass retained on 37.5 mm AS sieve is greater than 40%, do not report the relative compaction as the
test result obtained is not valid.

Do not use TfNSW T173 (nuclear gauge) for insitu density tests if the layer thickness exceeds 300
mm.

Calculate the relative compaction using Test Method TfNSW T166.

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Determine the characteristic value of relative compaction in accordance with TfNSW D&C Q6.
Round off the relative compaction value and the characteristic relative compaction value to the nearest
0.1%.

6.4.4 Compaction Method

Start the compaction at areas immediately adjacent to the wall, and then gradually proceed away from
the wall.

Do not use vibrating rollers of mass exceeding one tonne, or any other equipment that may potentially
cause damage to the earth retaining structure, to compact fill material located within 2 m behind the
structure. Provide, as part of your PROJECT QUALITY PLAN, details of your method for
compaction of fill located within this zone.

6.4.5 Backfilling Against Several Sides

When backfilling against several sides of a structure is required, maintain the level of the backfill at
approximately the same levels on opposing sides during backfilling.

In the case of frame structures (refer Clause 1.3 for definition), at any time during backfilling, the
difference in level of the backfill at opposing sides must not exceed 500 mm.

6.5 DRAINAGE ZONE BEHIND EARTH RETAINING STRUCTURES

Place granular drainage material complying with Clause 6.2.4 in the drainage zone behind retaining
structures to the extent shown on the Design Documentation drawings.

Provide within the drainage zone a corrugated perforated plastic subsurface drainage pipe, discharging
into the drainage system.

Provide a geotextile complying with Specification TfNSW D&C R63 to separate the granular drainage
material from the adjoining fill material.

Alternatively, subject to the Principal’s concurrence, where the drainage zone is less than 3 m high, the
granular drainage material may be substituted by a geocomposite membrane of equivalent drainage
capacity.

6.6 DISPOSAL OF SURPLUS EXCAVATED MATERIAL

Unless otherwise specified or accepted by the Principal, remove and dispose of all surplus excavated
material from the Site.

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ANNEXURES B30/A TO B30/B – (NOT USED)

ANNEXURE B30/C – SCHEDULES OF HOLD POINTS AND IDENTIFIED

RECORDS
Refer to Clause 1.2.3.

C1 SCHEDULE OF HOLD POINTS

Clause Description
3 Submission of cofferdam and/or shoring details
4.4 Inspection of foundation prior to placing mass concrete blinding layer

C2 SCHEDULE OF IDENTIFIED RECORDS

The records listed below are Identified Records for the purposes of TfNSW D&C Q6.

Clause Description of Identified Record

6.2.1 Details of source, location, quantities and type of imported Select Fill.

ANNEXURE B30/D – PLANNING DOCUMENTS

Refer to Clause 1.2.4.

The following documents are a summary of documents that must be included in the PROJECT
QUALITY PLAN. The requirements of this Specification and others included in the deed must be
reviewed to determine additional documentation requirements.

Clause Description
3 Details of cofferdam and/or shoring.
3 Method of installation and removal of cofferdam.
6.4.4 Method of compaction of fill material located within 2 metres behind earth retaining
structure.

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ANNEXURE B30/E
The following pages of Annexure B30/E are included for information only. The statements on
measurement and payment do not apply to D&C contracts.

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ANNEXURE B30/E – EXCAVATION, SELECT FILL AND DRAINAGE ZONE VOLUMES FOR MEASUREMENT AND
PAYMENT PURPOSES
LEGEND
Excavation volume measured and paid for
Finished surface (shown for
under Annexure B30/B Pay Item (a)
illustration purposes only)
Select Fill volume measured and paid for under
Annexure B30/B Pay Item (c)
Natural surface (shown for
illustration purposes only) Drainage zone volume measured and paid for
under Annexure B30/B Pay Item (e)

1000 mm

H
(1)
See Note
See Note (1)
Indicative extent of excavation (shown Finished surface (shown for
for illustration purposes only) 300 mm illustration purposes only)

Natural surface (shown for

illustration purposes only)

H/2
Indicative extent of excavation (shown
Mass concrete for illustration purposes only)
blinding layer
Notes:
(1)
The details shown above serves only to indicate the extent of the volumes of excavation, Select Fill backfill and drainage zone that are measured and paid for under
Annexure B30/B. These volumes are measured net, with no account taken in the measurement for payment of any additional excavation and backfilling necessitated by the
construction method adopted, and the rates are deemed to have made due allowance for any additional excavation and backfilling so required.
(2)
The actual details shown on the Drawings may differ from the details and dimensions shown above, in which case the details and dimensions shown on the Drawings take
precedence over those shown above.
(3)
The features other than the Select Fill backfill and drainage zone shown adjacent to the retaining structure serves merely to illustrate possible configurations in the finished
works. The actual works required will be shown on the Drawings, and constructed in accordance with the relevant specifications.

Figure B30/E.1

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LEGEND

Natural surface (shown for

illustration purposes only) Excavation volume measured and paid for
under Annexure B30/B Pay Item (a)

Footpath (shown for Select Fill volume measured and paid for under
Shown for illustration purposes only) Annexure B30/B Pay Item (c)
illustration purposes
only 1000 Drainage zone volume measured and paid for
under Annexure B30/B Pay Item (e)
Pavement

Upper Zone of Formation

H Natural surface (shown for
illustration purposes only)
See Note (1)
Finished surface (shown for
300 mm
illustration purposes only)
Indicative extent of excavation (shown
for illustration purposes only)

See Note (1)

Indicative extent of excavation (shown

for illustration purposes only)
H/2
Mass concrete
blinding layer

Notes:
(1)
The details shown above serves only to indicate the extent of the volumes of excavation, Select Fill backfill and drainage zone that are measured and paid for under
Annexure B30/B. These volumes are measured net, with no account taken in the measurement for payment of any additional excavation and backfilling necessitated by the
construction method adopted, and the rates are deemed to have made due allowance for any additional excavation and backfilling so required.
(2)
The actual details shown on the Drawings may differ from the details and dimensions shown above, in which case the details and dimensions shown on the Drawings take
precedence over those shown above.
(3)
The features other than the Select Fill backfill and drainage zone shown adjacent to the retaining structure serves merely to illustrate possible configurations in the finished
works. The actual works required will be shown on the Drawings, and constructed in accordance with the relevant specifications.

Figure B30/E.2

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LEGEND
Excavation volume measured and paid for
under Annexure B30/B Pay Item (a)
Shown for illustration
Shown for Select Fill volume measured and paid for under
purposes only Annexure B30/B Pay Item (c)
illustration
purposes only
Drainage zone volume measured and paid for
Pavement Approach slab under Annexure B30/B Pay Item (e)
Bridge superstructure
Upper Zone of Formation 1000 mm

Natural surface (shown for H 300 mm

See Note (1) Finished surface (shown for
illustration purposes only)
illustration purposes only)

See Note (1)

Indicative extent of excavation (shown Natural surface (shown for illustration purposes only)
for illustration purposes only)
H/2 Indicative extent of excavation (shown for illustration purposes only)

Mass concrete blinding layer

Pile

Notes:
(1)
The details shown above serves only to indicate the extent of the volumes of excavation, Select Fill backfill and drainage zone that are measured and paid for under
Annexure B30/B. These volumes are measured net, with no account taken in the measurement for payment of any additional excavation and backfilling necessitated by the
construction method adopted, and the rates are deemed to have made due allowance for any additional excavation and backfilling so required.
(2)
The actual details shown on the Drawings may differ from the details and dimensions shown above, in which case the details and dimensions shown on the Drawings take
precedence over those shown above.
(3)
The features other than the Select Fill backfill and drainage zone shown adjacent to the retaining structure serves merely to illustrate possible configurations in the finished
works. The actual works required will be shown on the Drawings, and constructed in accordance with the relevant specifications.

Figure B30/E.3

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LEGEND
Select Fill volume measured and paid for under
Annexure B30/B Pay Item (c)
Shown for illustration Drainage zone volume measured and paid for
Shown for purposes only under Annexure B30/B Pay Item (e)
illustration 1000 mm
purposes only Spill through bridge abutment fill material
Approach slab measured and paid for under TfNSW R44
Pavement
Bridge superstructure
Upper Zone of Formation

H 300 mm
Extent of wing wall (shown for
illustration purposes only)
H/2

See Legend

Pile Natural surface (shown for

illustration purposes only)

Notes:
(1)
The details shown above serves only to indicate the extent of the volumes of Select Fill backfill and drainage zone that are measured and paid for under Annexure B30/B.
These volumes are measured net, with no account taken in the measurement for payment of any additional excavation and backfilling necessitated by the construction method
adopted, and the rates are deemed to have made due allowance for any additional excavation and backfilling so required.
(2)
The actual details shown on the Drawings may differ from the details and dimensions shown above, in which case the details and dimensions shown on the Drawings take
precedence over those shown above.
(3)
The features other than the Select Fill backfill and drainage zone shown adjacent to the retaining structure serves merely to illustrate possible configurations in the finished
works. The actual works required will be shown on the Drawings, and constructed in accordance with the relevant specifications.

Figure B30/E.4

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Excavation and Backfill for Bridgeworks B30

LEGEND
Excavation volume measured and paid under
Annexure B30/B Pay Item (a)

Pier
Natural surface (shown for
column Earth fill complying with Clause 6.2.3
illustration purposes only)

See Note (1) See Note (1)

Indicative extent of excavation (shown Footing Indicative extent of excavation (shown
for illustration purposes only) (Pilecap similar) for illustration purposes only)

Mass concrete
blinding layer

Notes:
(1)
The details shown above serves only to indicate the extent of the volume of excavation that is measured and paid for under Annexure B30/B. The volume is measured net,
with no account taken in the measurement for payment of any additional excavation and backfilling necessitated by the construction method adopted, and the rates are
deemed to have made due allowance for any additional excavation and backfilling so required.
(2)
The actual details shown on the Drawings may differ from the details and dimensions shown above, in which case the details and dimensions shown on the Drawings take
precedence over those shown above.
(3)
The features other than the earth fill backfill shown adjacent to the footing/pile cap serves merely to illustrate possible configurations in the finished works. The actual works
required will be shown on the Drawings, and constructed in accordance with the relevant specifications.

Figure B30/E.5

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Excavation and Backfill for Bridgeworks D&C B30

ANNEXURES B30/F TO B30/K – (NOT USED)

ANNEXURE B30/L – MINIMUM FREQUENCY OF TESTING

Refer to Clause 1.2.5.

Clause Characteristic Tested Test Method Minimum Frequency of Testing

Select Fill
6.2.1 Chemical properties TfNSW T123, One per 500 m3
T1010, T1011
6.2.2 Particle size distribution and TfNSW T102, One per 500 m3
coefficient of uniformity T106, T107
6.2.2 Plastic Index TfNSW T108, One per 500 m3
T109
6.4 Relative compaction TfNSW T119, One per layer, or one per 100 m2, or
T165, T166, T173 one per day, whichever is more
frequent
Earth fill
6.2.1 Chemical properties TfNSW T123, One per 500 m3
T1010, T1011
6.2.3 Maximum particle dimension TfNSW T280 One per 500 m3
6.2.3 Particle size distribution and TfNSW T106, One per 500 m3
coefficient of uniformity T107
6.4 Relative compaction TfNSW T119, In accordance with TfNSW D&C Q6
T165, T166, T173
Drainage Zone Material
6.2.1 Chemical properties TfNSW T123, One per 500 m3
T1010, T1011
6.2.4 Particle size distribution TfNSW T106 One per 500 m3

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D&C B30 Excavation and Backfill for Bridgeworks

ANNEXURE B30/M – REFERENCED DOCUMENTS

Refer to Clause 1.2.6.

TfNSW Specifications

TfNSW D&C G22 Work Health and Safety (Construction Work)

TfNSW D&C G36 Environmental Protection
TfNSW D&C G38 Soil and Water Management
TfNSW D&C G71 Construction Surveys
TfNSW D&C Q6 Quality Management System (Type 6)
TfNSW D&C R44 Earthworks
TfNSW D&C R63 Geotextiles (Separation and Filtration)
TfNSW D&C 3552 Subsurface Drainage Pipe (Corrugated Perforated and Non-perforated Plastic)

TfNSW Test Methods

TfNSW T102 Pre-treatment of Road Construction Materials by Compaction

TfNSW T106 Coarse Particle Size Distribution of Road Construction Materials (by Dry
Sieving)
TfNSW T107 Fine Particle Size Distribution of Road Construction Materials
TfNSW T108 Liquid Limit of Road Materials
TfNSW T109 Plastic Limit and Plasticity Index of Road Construction Materials
TfNSW T119 Field Density of Road Construction Materials (Sand Replacement Method)
TfNSW T120 Moisture Content of Road Construction Materials (Standard Method)
TfNSW T121 Moisture Content of Road Construction Materials (Sand Bath or Hot Plate
Method)
TfNSW T123 Ph Value of a Soil (Electrometric Method)
TfNSW T165 Density In Situ of Road Construction Materials (Fixed Volume Extractive
Method)
TfNSW T166 Relative Compaction of Road Construction Materials
TfNSW T173 Field Wet Density of Road Construction Materials (Nuclear Gauge in Direct
Transmission Method)
TfNSW T180 Moisture Content of Road Construction Materials (Microwave Oven Method)
TfNSW T280 Determination of Maximum Particle Dimension of Road Construction Materials
by Direct Measurement
TfNSW T1010 Quantitative Determination of Chlorides in Soil
TfNSW T1011 Quantitative Determination of Sulphates in Soil
TfNSW T2105 Correlation of Moisture Content with Standard Method

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