Municipal Inspection and Construction Guidelines
Section I – Roadworks
SECTION I
ROADWORKS
I-1
GENERAL
The Consultant Engineer is to monitor all specified asphalt, granular materials and sub-grade
preparation to ensure all road and curb construction is undertaken as outlined in the criteria
below.
I-1.1
Road Composition
The Geotechnical Consultant is to provide recommended road composition based on existing
conditions and proposed road use. All granular composition, pavement design and roadworks
installation must meet City of Markham minimum design thicknesses and testing requirements.
Recycled Concrete Material shall be permitted in lieu of virgin granular A, B or crusher run
limestone material, subject to meeting City of Markham Material Specification. The following is
a typical minimum road composition; generally the Geotechnical Consultant will provide a site
specific recommendation to be followed:
Residential
Top Asphalt
Base Asphalt
Base
HL3 - 40mm compacted thickness
HL8 - 75mm compacted thickness (one lift)
20mm diameter - 150mm compacted thickness Crusher Run Limestone or
Granular “A”
Sub-Base
50mm diameter - 300mm compacted thickness Crusher Run Limestone or
Granular “B”
Collector & Industrial
Top Asphalt
HL3 - 50mm compacted thickness
Base Asphalt HL8 - 100mm compacted thickness (two lifts)
Base
20mm - 150mm compacted thickness Crusher Run Limestone or Granular “A”
Sub-Base
50mm - 450mm compacted thickness Crusher Run Limestone or Granular “B”
I-2
PRIMARY ROADWORKS
I-2.1
Pre-grade - Prior to Granular Import
Prior to commencing with importing materials for roadworks, the Consultant Engineer is to
check the grade sheets and layout to confirm the recommended road pre-grade elevations have
been satisfied and the sub-grade is in suitable condition to be overlaid with road granular.
Placement of granular prior to the City issuing approvals may result in complete removal of
granular. Special conditions such as winter construction or construction in wet conditions may
require full depth placement of granular material based on the recommendation of the
Geotechnical Engineer and acceptance by the City. The following items should typically be taken
into consideration prior to road granular import:
•
All materials surrounding manholes have been compacted to sub-grade
•
Sub-grade is graded and compacted to a 3% crossfall
City of Markham
Page 44
May 2015
Municipal Inspection and Construction Guidelines
Section I – Roadworks
•
Sub-grade is to extend 300mm beyond back of curb
I-2.2.1 Pre-grade Proof Roll
•
For proof rolling use of 40,000kg gross mass vehicle with pneumatic tires.
•
Non-standard proof rolling equipment will not be accepted.
•
Proof roll to be conducted at road subgrade level.
•
Make sufficient passes with proof vehicle to subject every point on surface to three
separate passes of loaded tire.
•
Where proof rolling reveals areas of defective subbase, remove defective (soft)
subgrade materials to depth and extent as directed by Geotechnical Engineer and
replace with new dry materials as approved by the Geotechnical Engineer and City of
Markham.
•
Replace subbase material and compact in accordance with this section.
•
Finished subbase surface to be within 25 mm of elevation as indicated but not uniformly
high or low.
•
Maintain granular subbase in condition conforming to this section until succeeding base
is constructed, or until granular subabse is accepted by the Geotechnical Engineer.
The Consulting Engineer is to summarize the Proof Roll event in a Site Report form (see
Appendix XIV – Site Report), include the Geotechnical Consultant’s report and issue this to the
Developer, City of Markham, Contractor and Geotechnical Consultant.
The locations and depths of any additional granular to be used or any areas to be sub-excavated
are to be recorded by the Consulting Engineer and shown on as built drawings. Where extra
depth of material is required, the Consulting Engineer is to ensure the subdrains are low enough
(or adjusted) to drain these areas.
I-2.2
Road Sub-base
Road sub-base recommendations are to be provided by the Geotechnical Consultant based on
site conditions and proposed uses and approved by the City as part of the engineering approval
process. Road sub-base to be compacted to 100% SPD within 1 meter of finished road grade.
In accordance with the City of Markham standards and OPSS 314 and in working closely with the
Geotechnical Consultant, the following is to be adhered and monitored by the Consultant
Engineer:
•
Materials, depth and achieved compaction are per Geotechnical Consultant
recommendations (on site and outlined in geotechnical report).
City of Markham
Page 45
May 2015
Municipal Inspection and Construction Guidelines
Section I – Roadworks
•
Material shall be placed without segregation in uniform layers such that the thickness of
the compacted layer is not greater than 150mm, unless otherwise directed by the
Geotechnical Consultant.
•
Sub-base and base layers shall be bladed to a smooth surface in conformance to the
required cross-section and maintained until placement of a subsequent layer, where
applicable.
I-2.3
Subdrains
150mm diameter rigid HDPE perforated subdrains with geotextile sock are set on both sides of
the roadway to provide a ‘path of least resistance’ for water to drain out of the road base and
sub-base, to minimize water and frost damage. Subdrains to be installed at a uniform grade and
alignment and connectors to the catchbasins.
I-2.3.1 Subdrain Installation Requirements
The following is to be adhered and monitored by the Consultant Engineer, including reference to
City of Markham road cross sections MR- 1to MR-13:
•
Subdrains are to be 150mm diameter rigid HDPE perforated pipe enclosed by a
perforated geotextile sock placed continuously between catchbasins below the subbase.
•
Subdrain pipe is to be laid at a continuous grade with no settlements in the pipe.
•
20mm diameter clear stone or HL6 stone backfill is to be used around all subdrains,
unless otherwise specified by the Geotechnical Engineer and approved by the City of
Markham.
•
The invert of the subdrain is to be higher than obvert of the catchbasin lead to the
mainline sewer to ensure adequate drainage.
•
Where utility road crossing (hydro, gas, etc.) have been installed after the roadworks,
specific attention must be made to ensure the road sub-drain has not been damaged
and that it will continue to drain.
I-2.4
Road Base
Road base recommendations are to be provided by the Geotechnical Consultant based on site
conditions and proposed uses and approved by the City prior to import.
The following is to be adhered and monitored by the Consultant Engineer during road base
construction:
•
Materials, depth and achieved compaction are per Geotechnical Consultant
recommendations (on site and outlined in geotechnical report).
•
Material shall be kept free from clay and other types of deleterious material.
City of Markham
Page 46
May 2015
Municipal Inspection and Construction Guidelines
Section I – Roadworks
•
Material shall be placed without segregation in uniform layers such that the thickness of
the compacted layer is not greater than 150mm, unless otherwise directed by the
Geotechnical Consultant.
•
The granular base shall be maintained to grade and cross-section and to the specified
compaction until the surface is paved.
•
Prior to closing down operations for the completion of each day’s work, the sub-base
material shall be bladed and compacted.
•
Granular road base materials to be compacted to 100% SPD.
I-2.5
Base Curb
Prior to the Contractor pouring base curb, the Consulting Engineer is to ensure the following:
•
The vertical and horizontal placement of the stringline prior to base curb being poured
has been verified by survey.
•
The Geotechnical Consultant has reviewed the sub base material where the curb will be
placed and confirmed adequate compaction has been achieved (i.e. - 100% SPD).
•
Concrete mix designs have been provided by the Contractor and reviewed and approved
by the Geotechnical Consultant and the City.
•
Curb form to be per OPSD 600.040, 600.060, 600.070, 600.100 or 600.11, as referenced
on City approved drawings MR-14 and MR-15.
•
Concrete shall confirm to OPSS 1350 and the following specific requirements:
Class of Concrete
32 MPa at 28 days
Coarse Aggregate
19.0 mm nominal maximum size
Maximum Slump
60mm
Air Content
6.0% ± 1.5%
I-2.6
Base Asphalt
HL8 (base asphalt) is to be placed no later in the year than December 1 or below temperatures
of 2ºC as measured at the surface of the road. Ambient air temperatures during asphalt
placement are to be 2ºC and rising. The Geotechnical Consultant is to abide by the City’s listed
testing requirements (see Section B-2.2 and K-3). On site inspections during asphalt placement
works include testing for temperature, compacted thickness and degree of compaction.
The Consulting Engineer is to ensure asphalt mix designs have been provided by the Contractor
to the Geotechnical Consultant and reviewed and approved prior to placement.
I-2.6.1 Pre-Base Asphalt Inspection
Prior to base asphalt being laid, the Consulting Engineer is to coordinate a Proof Roll inspection
of the road base material with the Contractor, Geotechnical Consultant and City Inspector. The
City of Markham
Page 47
May 2015
Municipal Inspection and Construction Guidelines
Section I – Roadworks
Consulting Engineer is to ensure the road base materials have been previously tested by the
Geotechnical Consultant have met material quality (including material type and moisture
content) and compaction requirements.
Prior to asphalt works, the Consultant Engineer is to undertake an on site inspection with the
Contractor, Geotechnical Consultant and City of Markham ensuring the following is complete:
•
Sewer videos have been reviewed and all deficiencies reported have been rectified and
re-video recorded.
•
All manholes and catchbasins are to be set 5 to 10mm below the base asphalt elevation.
Asphalt ramping of asphalt to meet these structures is not permitted.
•
The correct lid has been placed on the manhole (i.e. sanitary, storm or FDC).
I-2.6.2 Base Asphalt Inspections
During asphalt works, the Consultant Engineer is to ensure the Contractor completing the work
undertakes the following:
•
Temporary asphalt curbs are to be placed behind each catchbasin.
•
Asphalt thicknesses and temperatures are achieved per Geotechnical Consultant
recommendations as approved by City of Markham.
•
Asphalt maintains a minimum 2% fall at all locations.
•
Asphalt is smooth and free of depressions.
•
The maximum length of an asphalt cold joint is 180m or a minimum asphalt
temperature of 85ºC.
•
Tack coat to be placed where asphalt abuts curb, against all ‘cold’ asphalt joints,
manholes, structures, etc.
I-3
UTILITY COORDINATION
In conjunction with primary roadworks the Consulting Engineer is to ensure that a utility
coordination meeting is held with a representative from the following parties: road works
contractor, City of Markham, Developer, Gas, Cable TV, Telephone, Markham District Energy
and Hydro utilities.
As part of utility coordination the following items should be considered:
•
•
Review the utility schedule to ensure this coincides with the overall roadworks schedule
and timing of all utilities.
Ensure that all utility design approvals are in place and that all parties show their utilities
correctly on the City approved Composite Utility Plans.
City of Markham
Page 48
May 2015
Municipal Inspection and Construction Guidelines
Section I – Roadworks
•
A site inspection is to be coordinated by the Consultant Engineer with the Developer
and Electrical/Utility Contractor before and following installation to ensure all
underground servicing and roadworks have not be damaged due to utility construction.
These site inspections are to be documented by the Consultant Engineer in the Site Visit
Report (Appendix XIV).
I-4
SECONDARY ROADWORKS
I-4.1
Base Curb Inspections
Base Curb inspections are completed to ensure a quality foundation is in place for the
placement of top curb. Generally, any settling, grading, damaged stirrups or foundation issues
will be dealt with before top curb is poured. See Appendix XVII – Inspection Guidelines for
Rectification Requirements for criteria to be referenced during base curb inspections.
The Consulting Engineer is to coordinate base curb inspections with the Contractor, Consultant
and City Inspector. The Consulting Engineer should document any base curb deficiencies
including the length and location (street name and station) of curb to be removed and replaced
(where cracked or missing sections), locations requiring saw cuts and areas where stirrups are to
be replaced in accordance with Appendix XV – Base Curb Inspection Report. Subsequent
inspections are to be coordinated and undertaken if repairs to the base curb are required. Once
all deficiencies have been rectified if any noted, a final inspection will be completed to approve
the base curb foundation prior to top curb being poured.
All base curb replacement sections shall be formed and constructed with a “key” and stirrups.
I-4.2
Top Curb
Prior to the Contractor pouring top curb, the Consulting Engineer is to ensure concrete mix
designs have been reviewed and approved by the Geotechnical Consultant and the City. During
preparations for top curb temporary asphalt fillers are removed from behind catchbasins and
replaced with the top curb concrete.
Prior to the Contractor pouring top curb, per City recommendations and OPSS 353 the
Consulting Engineer is to ensure the following:
•
Concrete mix designs have been provided by the Contractor and reviewed by the
Geotechnical Consultant.
•
Curb form to be per OPSD 600.040, 600.060, 600.070, 600.100 or 600.11, as referenced
on City approved drawings.
•
Concrete shall confirm to OPSS 1350 and the following specific requirements:
Class of Concrete
32 MPa at 28 days
Coarse Aggregate
19.0 mm nominal maximum size
Maximum Slump
60mm
Air Content
6% ± 1.5%
All base curb shall be thoroughly cleaned prior to placement of top curb works.
City of Markham
Page 49
May 2015
Municipal Inspection and Construction Guidelines
Section I – Roadworks
One stage curb shall be installed adjacent to all school and park blocks prior to base asphalt
placement.
I-4.3
Concrete Sidewalk and Multi-Use Pathway
The Consultant Engineer is to monitor all preparations, formworks and materials and ensure the
outlined criteria below is adhered during construction of sidewalks. Concrete sidewalks are to
be installed in accordance with the City standard MR-20 through MR-24.
The work required for concrete sidewalk shall include earthwork, 50mm (minimum) granular ‘A’
base, compaction, preparation work, form work, utility adjustment and isolation, concrete
placing and finishing, jointing, curing and protection. A plastic membrane shall be laid over the
subgrade, prior to placing concrete.
I-4.3.1 Sidewalk Materials
Concrete shall confirm to OPSS 1350 and the following specific requirements:
Class of Concrete
30 Mpa at 28 days
Coarse Aggregate
19.0 mm nominal maximum size
Air Content
6% ± 1.5%
Maximum Slump
50 ± 20mm
Expansion joints shall be filled with bituminous fiberboard material having a minimum of 12mm
thickness and conform to Type “A” material in OPSS 1308.
Material used for sidewalk granular base shall conform to OPSS 1010.
Curing compound shall conform to OPSS 1315.
I-4.3.2 Joints
Per OPSS 351, longitudinal and transverse joints shall be constructed of the type, and at the
locations, specified in the Contract. The concrete adjacent to all formwork and joints shall be
finished with a tool that produces a 5mm rounded edge and a smooth, horizontal surface with a
maximum width of 50mm.
Dummy joints shall be hand formed using a 5mm radius dummy joint tool (refer to City standard
MR-20 and MR-21).
Contraction joints shall be placed at every third dummy joint and shall be sawcut or formed to a
depth which is 0.25 of the sidewalk thickness.
Expansion joints shall be constructed to the full depth of the slab. Expansion joints shall be filled
with expansion joint material and shall be clean and dry at the time of construction. These
joints shall be constructed where the sidewalk abuts a rigid object or changes direction.
City of Markham
Page 50
May 2015
Municipal Inspection and Construction Guidelines
Section I – Roadworks
I-4.3.3 Sidewalk Installation Requirements
City of Markham standard MR-20 through MR-24 and the following are to be adhered and
monitored by the Consultant Engineer:
During sidewalk construction, the Consultant Engineer is to ensure the following:
•
Concrete mix designs have been provided by the Contractor to the Geotechnical
Consultant and reviewed and approved prior to use.
•
Sidewalk forms are per City approved design drawings and OPSS 919.
•
Proper bedding including a plastic barrier has been placed prior to concrete being
poured.
•
Sidewalk maintains a minimum 2% fall (maximum 4%) at all locations.
•
Sidewalk ramps do not exceed a maximum slope of 5%.
•
Geotechnical Consultant is on site and testing is completed for every 100 cubic meters
of concrete. Minimum of one set of tests for each day.
•
All sidewalk repair or replacement sections shall include the immediate restoration of
the boulevard including the placement and watering of sod and asphalt replacement as
required.
I-4.4
Top Asphalt
The Consulting Engineer is to ensure the roads and infrastructure is prepared prior to the
scheduled date of top asphalt, including all base asphalt and curb repairs. Base asphalt and curb
shall be thoroughly cleaned prior to placement of top asphalt and curb. Base asphalt has been
inspected and manholes and catchbasins adjusted to match the proposed finished asphalt
elevations.
HL3 (top asphalt) is not to be placed later in the year than November 14 or below ambient air
temperatures of 7ºC as measured at the surface of the road. The Consulting Engineer is to
ensure asphalt mix designs have been provided by the Contractor to the Geotechnical
Consultant and reviewed and approved prior to use.
The Geotechnical Consultant is to abide by the City’s listed testing requirements (see Section B2.2 and K-3). On site inspections during asphalt laying works shall include but not limited to
testing for temperature, asphalt material content and compacted thickness and compaction.
I-4.4.1 Base Asphalt Inspections
Base Asphalt inspections are completed to ensure a quality base is in place for the placement of
top asphalt. Any settling, grading, or base issues will be preemptively dealt with before top
asphalt is placed. The Consulting Engineer is to coordinate base asphalt inspections with the
Contractor, Geotechnical Engineer and City Inspector. The Consulting Engineer must also
City of Markham
Page 51
May 2015
Municipal Inspection and Construction Guidelines
Section I – Roadworks
prepare a Site Report (see Appendix XIV – Site Report) tracking the inspection noting any base
asphalt deficiencies including the length and location (street name and station) of base asphalt
to be ground or removed and replaced where cracked or otherwise damaged.
Subsequent inspections are to be coordinated and undertaken if repairs to the base asphalt are
required. Once all deficiencies have been rectified if any noted, a final inspection will be
completed by the Consulting Engineer, Geotechnical Engineer, Contractor and City Inspector to
approve the base conditions prior to placement of top asphalt.
I-4.4.2 Tack Coat Material
Immediately prior to top asphalt being laid a ‘tack coat’ layer is to be placed. Per City of
Markham standards and OPSS 310, the tack coat shall consist of SS-1 emulsified asphalt diluted
with an equal volume of water. This material is to coat the surface of the base asphalt, curbs
and manholes which will aid in the top asphalt binding to all surfaces.
I-4.4.3 Top Asphalt Installation Requirements
During asphalt works, the Consulting Engineer is to ensure the Contractor completing the work
undertakes the following:
I-5
•
Asphalt is to be mixed and compacted per OPSS 310 and confirmed by the Geotechnical
Consultant.
•
Asphalt thicknesses and temperatures are achieved per the approved design and
Geotechnical Consultant recommendations as approved by City of Markham.
•
Asphalt maintains a minimum 2% fall at all locations.
•
Asphalt is smooth and free of depressions.
•
The maximum length of an asphalt cold joint is 180m or a minimum asphalt
temperature of 85ºC.
ROADWAY RESTORATION
The Consulting Engineer is to ensure any disturbed unpaved road surfaces are prepared to the
required grades and density ready for a subsequent cover of granular or surfacing courses. Per
OPSS 301, restoring roadway surfaces shall consist of the following:
a) The scarification (uniform loosening to remove damaged areas) of the existing surface
to a depth not less than 75mm, but sufficient to remove potholes.
b) Restoring or reshaping the scarified material.
c) Compacting of the scarified materials according to OPSS 501.
d) Ensuring the finished surface is within tolerance by checking the accuracy with the cross
section.
City of Markham
Page 52
May 2015
Municipal Inspection and Construction Guidelines
Section I – Roadworks
The Contractor is responsible to maintain the scarified surface to the profile, cross-section, and
density until the project is accepted or if applicable, until any subsequent granular or surfacing
course is completed.
Unsuitable material encountered during restoring operations shall be removed to a depth not
less than 150mm and replaced by acceptable granular material.
I-6
DRIVEWAY RESTORATION
Throughout construction works, access to driveways must be maintained unless otherwise
arranged. Per OPSS 311 and the City of Markham, the Consultant Engineer is to ensure the
following is to be adhered and monitored:
I-7
•
The hot mix asphalt shall be placed on the prepared base to the line, grade, dimensions,
and thickness outlined in the City approved engineering design. The prepared base shall
be dry, well compacted, and approved by the Geotechnical Consultant.
•
Hot mix asphalt shall not be placed unless the surface is dry and the air temperature is
at least 7ºC and rising. Asphalt shall not be dumped faster than it can be properly
raked, screeded and compacted.
•
Areas inaccessible to a roller shall be compacted with hand operated hot tampers.
•
The sidewalks, driveways, and boulevards and the resurfaced sidewalks shall not be
opened to pedestrians or vehicles until the mix has cooled sufficiently to prevent
deformation.
•
Forms or other approved means shall be used to obtain proper line and neat uniform
edges.
ROAD SETTLEMENT
If in the opinion of the City, settlement has occurred at the base course or top course of asphalt
levels, a road review will be required to determine the structural integrity of the road. The cost
of any additional testing or analysis by a Geotechnical Engineer will be borne by the Developer.
A review of the condition of the roads determines whether the maintenance period of the road
should be extended or if reconstruction is required.
I-8
PAVEMENT MARKING
All pavement markings as shown on the approved engineering drawings including but not
limited to center line, stop bars, pedestrian crossings, bicycle lanes and parking spaces shall be
installed upon the completion of base asphalt and again upon completion of top course asphalt.
The pavement markings on base asphalt shall be painted with two coats including glass
reflective beads. Durable rubberized pavement markings shall be used on top asphalt. At the
discretion of the City, the pavement markings shall be repainted/refreshed as required prior to
final assumption of the development.
Pavement markings shall be in accordance with OPSS 1715 & 1716, see Appendix XXIX.
City of Markham
Page 53
May 2015
Municipal Inspection and Construction Guidelines
Section I – Roadworks
Line painting shall be as per OPSS 1712: Material Specification for Organic Solvent Based Traffic
Paint. As well as OPSS 1750-1: Material Specification for Traffic Paint Reflectorizing Glass Beads.
I-9
SECTION I SUMMARY CHECKLIST
•
Consultant Engineer is to collect all grade sheets, review and survey site to ensure
specified asphalt and granular materials are placed per the approved drawings.
•
Geotechnical Consultant is on site as required based on the construction schedule.
•
Proof roll review and inspection test is coordinated with the Contractor, Developer,
Geotechnical Consultant and the City for the pre-grade prior to the placement of
granular.
•
Road sub-base and base are placed as per the City Requirements outlined in Sections I3.2 and I-3.4.
•
Base curb mix design is approved and Contractor string line is verified.
•
Proof roll review and inspection test is coordinated with the Contractor, Developer,
Geotechnical Consultant and the City for the road base prior to the placement of base
asphalt.
•
Base asphalt mix design is approved and inspections are completed.
•
Base asphalt is placed per the specified conditions outlined in Section I-3.6.
•
Base curb inspections are completed as per Appendix XV – Base Curb Inspection Report
and deficiencies have been rectified.
•
Top asphalt mix design is approved and base asphalt inspections/proof roll are
completed as per Section I-4.4.
•
Consultant Engineer is to coordinate and carry out inspections related to roadworks, top
curbs, sidewalks, top asphalt, boulevard grading and sodding for Acceptance for
Maintenance and Final Assumption.
City of Markham
Page 54
May 2015