4-MTW Specifications for reinstatements of small openings, crossings, tracks and signage.pdf

SPECIFICATIONS FOR

REINSTATEMENTS

OF SMALL OPENINGS/CROSSINGS

TRACKS & SIGNAGE

PREPARED BY

METHOD/ANALYSIS SECTION

(Utility Coordination)

Revised April 2023

MINISTRY OF TRANSPORT AND WORKS

MINISTRY OF TRANSPORT AND WORKS

Ref: CTO/R.20

Specifications for Reinstatements of Small Openings/Crossings

i. Cart away all loose material, and excavate to a sound foundation ensuring that the sides of the openings are square.

ii. Compact base sides, which should be dry prior to the reinstatement.

iii. Apply emulsified asphalt to sides and base, then place and compact in 3" (75mm) layers with hot mix asphalt or premix asphalt (chip thoroughly coated with asphalt).

iv. The final surface of the work should be at the level of the existing road

Tracks

i. After the Utility Company has installed its pipes/ cables etcetera, the track may be back-filled with excavated material provided that the quality is satisfactory to the Chief Technical Officer, that is, no organic matter of soil. The backfill material should be placed in layers not exceeding 150mm (6") thick and compacted. These compacted layers should be brought to within 375mm (15 ) of the surface.

ii. Marl-fill should then be placed in the trench and compacted in 150mm layers up to 75mm (3") from road surface.

iii. A little more than 75mm (3 ) of 37mm (15 ) stone should[ be placed on top of the marl, so that it is slightly proud of the road, and rolled with a 8 to 10 tonne roller. Any unevenness in the surface should be made up with more crushed material

iv. The stone above should then be penetrated with emulsified asphalt a rate of 4 litres per square meter covered with 6mm chips, and further rolled with a similar roller as at (iii)

v. Where the existing surface is already hot mix asphalt (barber-greened) then paragraph

iii) and iv) will not apply, instead 75mm of hot mix should be placed in the trench, compacted and rolled in with an 8 to 10 tonne roller.

vi. The finished surface should be even and level with the existing road. In the case of both openings and tracks, the Utility Company will ensure that there is no damage nor settlement to their work. For openings, the maintenance period will be six (6) months, while for the tracks the period will be one (1) year.

vii. Where the opening or track has settle down during the maintenance period, the Utility Company will return and raise the track to the existing road surface, using the same asphalt material as was used for the top 75mm(3") layer.

viii. These crossings should be completed and backfilled to provide an adequate riding surface to vehicular traffic during the week days until the compaction has been approved.

Minimun Proctor + 95% Modified Proctor of Test C T18093 of AASHTO

Maximum Proctor = 100 + % (or as the quarry dictates).

ix. Periodic meetings should be carried out with our Traffic Management Section on site to ensure that the measures taken are feasible or to modify them to accommodate the conditions at the time of your operations, hence minimising the inconvenience to the public and increasing the safety factor.

x. On completion of your backfilling and compaction to specifications, this Ministry must be informed via the Deputy Chief Technical Officer (Operations) before temporary or the final surface crossing of Hot Asphalt Concrete is applied. The Ministry will carry out "Nuclear Density Gauge test to ensure that the compaction has met the required density".

Other Mandatory Instructions

Prior to your works:

a) The other Utility Companies must be informed of this construction programme as it relates to their existing underground plant at this project.

b) The Commissioner of Police, the Labour Officer and the general public must be notified about the project, its starting time and duration.

c) The drainage Unit which now has the responsibility for the drainage facilities at the public carriageways must be notified about the project and details given of how you propose to execute works around these facilities.

d) The edges of all tracks should be cut as clean and square as possible using a graphite blade or similar mechanical cutting saw to cut the first 3" depth (75mm) of asphalt concrete surface; 3' (900mm) off edge and to be implemented in conjunction with the attached Civ/75: Required Technical Works to Maintain the Integrity of the Public Roads.

e) All consideration must be given to the travelling public (all public transport authorities), commercial operations and the pedestrian traffic in these areas, therefore the media as well must be constantly used to up-date and inform them of these activities.

f) The timing of this work and the co-ordination of the traffic control should be reviewed with our Technical Officer I or Technical Officer 2, Traffic Management Section as you proceed.

g) Adequate barricades, warning signs and lights should be used and some manual form of assistance rendered towards the traffic control. A specimen document of the signs that can be used is attached.

h) The selected materials could be excavated materials but should be free from all organic matter, mould, et cetera, well compacted in 150mm (6") layers and brought to the level of existing road surface for compaction testing.

i) The filling must not contain aggregate greater than 100mm (4") in size and must have the following gradation:

Grade A

Designation or Percent Passing Marlfill Material Sieve Size

75mm (3") 100

50mm (2") 65-85

25mm (1") 35-70

9.5mm (3/8) 30-60

2.00mm (No 10 Sieve) 20-60

0.452mm (No 100 Sieve) 12-25

0.075mm (No 200 Sieve) 6-11

Grade B

50 mm (2") Down Crusher Run

Sieve Size% Passing

50 mm (2") 100

37.5 mm (1 ½) 90-100

19 mm(¾) 50-90

.2 mm (#10) 20-55

0.075 (#200) 0-15

Also in our tests the Ministry will indicate the maximum compaction density that the selected backfill can attain based on the quarry. This will provide you with the flexibility for determining where the temporary or permanent reinstatement can be carried out.

The reinstatement will be governed by the specifications as set out in our attached document Ref: CTO/R20 "Specifications for Reinstatements AND Small Openings/Crossings" and as supported by the attached extract from the general details which you will carry out to this Ministry's satisfaction.

Drainage

Please monitor and ensure that all of your duct systems pass under these facilities with adequately compacted back-filling of concrete floated under the boxed drain, crossed culvert slippers, curbs, et cetera and vibrated thoroughly to ensure complete compaction as per the attached general details.

Those culverts that are damaged or collapsed as a result of this construction work must be re-established by you with the prerequisite reinforcement.

The concrete footpaths, drainage, et cetera, must be re-established with 1:2:4 concrete mix to the existing full depth and reinforcement.

Required Detail

All services must be placed at a minimum depth of 3' (900mm) below the finished road surface and must pass under the established water mains where they intercept.

With respect to the attachment Civ/75:

Required Technical Works to Maintain the integrity of the Public Roads a mechanical paving machine must be used to apply the Hot Asphaltic Concrete when a lane or the width of the carriageway is to be paved as required by item #2 and #3 of this regulation.

REF: ' CTO/G12:

Road Signs for Maintenance and Construction Work

In efforts to reduce the risk of danger to motorist and workers alike during the operations of road work projects, Outlined below are guidelines to the type of signs/signage which should be used while such road works projects are being carried out.

1. DISTANCE FROM SITE WORD ARRANGEMENT

1) 150m Ahead

2) 75m Ahead

3) 50m Ahead

4) 50m After

2. Signs (I) and (2) should be diamond shaped with black letters on an orange back-ground,-, while signs ( 3*) and (4) are rectangular with the same color scheme.

3. The following "accessories" should be used to call attention to the early warning signs (I) and (2):

i. Orange triangular flags mounted at either side of these signs .

ii. Either flashing warning lights should be mounted at the top of the signs or reflective strips attached along borders and/or stands for increased night time visibility.

iii. All channelizing devices e.g., traffic cones, barricades, etc., should be lit or reflective . x

4. When Road Closures are necessary, the following may be erected as appropriate:

I.

II.

*These Signs Should have

White background and Black letters.

5. These signs 'should be placed at the most convenient detour routes and should only be used to mark roads that have been closed to all traffic.

i. White Background And Black Letters

ii. Black Background And Letters, Orange Arrow

6. The following sign, should be used for major road works which call for long periods of rerouting etc. for road users:

i. Orange Background Black Letters

7. You are requested to have a sufficient number of these signs together with their stands made and kept available for use. Note that the signs must be made in complete accordance with the above instructions in the interest of standardization. All signs should have a border of inch reflective tape stuck on them. Also special attention must be paid to erecting the signs the recommended distances ahead and after the road works and removing them upon completion. It is your responsibility to ensure that all workers are made familiar with the proper use of the signs.

8. Maintaining good public relations is necessary. We do get co-operation from the various news media and police re: publicizing the existence of and reasons for the work but for one reason or another the road user may have missed these notices and so must be give clear directions when moving through the work sites. These signs and other aids were devised for this reason as well.

Ref. CIV/75 (Revised 2023)

Required Technical Works to Maintain the Integrity of the Public Roads

1.0 EXECUTION

1.01 TRENCHING:

A. Trench Dimensions: The width of the trench shall be as shown in the table given below:

Pipe Diameter Minimum Trench Width Maximum Trench Width

25mm through 200mm O.D. + 300mm O.D. + 450mm

250mm through 400mm O.D. + 400mm O.D. + 600mm

450mm through 600mm O.D. + 500mm O.D. + 900mm

675mm through 900mm O.D. + 600mm O.D. +1200mm

LENGTH OF OPEN TRENCH

The length of open trench is limited to 100 metres (approx.300 feet) in advance of pipelaying or amount of pipe installed in one working day. Backfilling and temporary or first layer paving is to be not more than 40metres (130 feet) in the rear of pipelaying.

B. Trench Grade: Standard trench grade shall be defined as the bottom surface of the utility to be constructed or placed within the trench. Trench grade for utilities in rock or other non-cushioning material shall be defined as below the outside of the bottom of the utility, which shall be backfilled with extra utility bedding material. Excavation below trench grade that is done in error shall be backfilled to trench grade with granular material and compacted.

C. Utility Bedding: The bottom of the trench shall be shaped to provide a firm bedding for the utility pipe. The utility shall be firmly bedded in undisturbed firm soil, or hand-shaped unyielding material. The bedding shall be shaped so that the pipe will be in continuous contact therewith for its full length and shall provide a minimum bottom segment support for the pipe equal to one-half of the outside diameter of the barrel. Special bedding may be required, due to depth of cover, impact loadings, or other conditions.

D. Unsuitable Material Below Trench Grade: Soil unsuitable for a proper foundation encountered at or below trench grade, such as muck or other deleterious material, shall be removed for the full width of the trench and to the depth required to reach suitable foundation material, unless special design considerations rec

E. Extra Utility-Bedding Material: When rock or other non-cushioning material is encountered at trench grade, excavation shall be extended to below the outside of the bottom of the utility, and a cushion of granular material shall be provided. For the purpose of this specification, granular material is material for which the sum of the plasticity index and the percent of material passing a No.200 sieve does not exceed 23. The plasticity index shall be tested in accordance with AASHTO T-146, T-89 and T-90. The percent of the material passing a No. 200 sieve shall be tested in accordance with ASTM C136 and ASTM C117.

F. Sheeting and Bracing: In order to prevent damage to property, injury to persons, erosion, cave-ins, or excessive trench widths, adequate sheeting and bracing shall be provided, as required, and/or directed by the Engineer, in accordance with accepted standard practice. When the situation arises, sheeting and bracing shall be used as necessary to protect the integrity of the road shoulder. Sheeting shall be removed when the trench has been backfilled to at least one-half its depth, or when removal would not endanger the construction of adjacent structures.

When required, to eliminate excessive trench width or other damage, sheeting, bracing, or shoring shall be left in place and the top cut off at an elevation of below finished grade, unless otherwise directed.

G. Excavated Material: Excavated material to be used for backfill shall be neatly and safely deposited at the sides of the trenches where space is available. Whenever possible, excavated material near a roadway should be deposited on the right-of-way side of the trench away from the travel way. Where stockpiling of excavated material is required, the Contractor shall be responsible for obtaining the sites to be used and shall maintain his operations to provide for natural drainage and not present an unsightly appearance. All sites shall be restored after fill is removed.

Native material used for backfill shall be sound material free from broken concrete, broken pavement, wood or other deleterious material with no piece larger than 100mm (4

H. Material Disposal: Excess, unsuitable, or cleared and grubbed material resulting from the utility installation shall be removed from the work site and disposed of at a location(s) secured by the Contractor, and in accordance with the Ministry. Excess excavated material shall be spread on the disposal site and graded in a manner to drain properly and not disturb existing drainage conditions, in accordance with applicable permit requirements.

I. Borrow: Should there be insufficient satisfactory material from the excavations to meet the requirements for fill material, borrow shall be obtained from quarries secured by the Contractor and approved by the Ministry. All borrow shall meet the provisions of these specifications.

J. Rock Excavation: Rock excavation shall be defined as excavation of any hard natural substance that cannot be removed by a one cubic metre bucket and requires the use of explosives and/or special impact tools such as jackhammers, sledges, chisels, or similar devices specifically designed for use in cutting or breaking rock.

K. De-watering may be dewatered by using one or more of the following methods: well point system, sumps with pumps, or other methods(s) as approved by the Engineer. Dewatering systems shall be utilized in accordance with good standard practice and must be efficient enough to lower the water level in advance of the excavation and maintain it continuously to keep the trench bottom and sides firm and dry. If the material encountered at trench grade is suitable for the passage of water without destroying the sides or utility foundation of the trench, sumps may be provided at intervals at the side of the main trench excavation, with pumps used to lower the water level by taking their suction from said sumps. Discharge from dewatering shall be disposed of in such a manner that it will not interfere with normal drainage of the area in which the work is being performed or create a public nuisance. The operations shall not cause injury to any portion of the work completed, or in progress, or to the surface of roads, or to private property.

Additionally, where private property will be involved, advance permission shall be obtained in writing by the Contractor from the property owner.

L. Obstructions:

conditions and to locate structures and utilities along the proposed utility alignment in order to avoid conflicts. Where actual conflicts are unavoidable, work shall be coordinated with the facility owner and performed so as to cause as little interference as possible with the service rendered by the facility disturbed. All affected utilities shall be notified prior to excavation in their vicinity.

Compaction Methods: The above-specified compaction shall be accomplished using accepted standard methods (powered tampers, vibrators, etc.), with the exception that the first 300mm of backfilling over the pipe shall be compacted by hand-operated tamping devices.

Density Tests: Density tests for determination of the above-specified compaction shall be made

If any test results are unsatisfactory, the Contractor shall re-excavate, re-compact the backfill, and retest, at his expense until the desired compaction is obtained. Additional compaction tests shall be made to each side of an unsatisfactory test, as directed, to determine the extent of re-excavation and re-compaction necessary. In addition, the minimum compaction densities shall be as follows:

MINIMUM TRENCH COMPACTION DENSITITES

Backfill Type

Location From Surface to 2 feet below surface

From 2 feet below surface to 1 foot above top of pipe

From 1 foot above top of pipe to bottom of pipe

I. Under any existing or proposed pavement, curb, gutter, attached sidewalk, roadway, shoulders, and other areas within right-of-way subject to vehicular traffic, or when any part of the trench excavation is within 2-feet of the existing pavement, curb, or gutter.

100% for granular 95% for non-granular

95%

95%

II. On any utility easement or right-of-way outside limits of backfill.

85% 85% 90%

III. Around any structures (manholes, etc.) or exposed utilities outside limits of backfill.

95% in all cases

N. Pavement replacement: The contractor shall do such grading in the area adjacent to backfilled trenches and structures as may be necessary to leave the area in a neat and satisfactory condition approved by

All streets ,alleys, driveways, sidewalks, kerbs, or other surfaces in which the surface is broken into or damaged by the installation of the new work, shall be resurfaced as specified to the satisfaction of the engineer in accord

The job site shall be left in a neat and acceptable condition. Excess soil, concrete, shall be removed from the premises.

2.0 ROAD REINSTATEMENT

i. Tracks that are excavated at the road edge or immediately outside of the slipper drain, boxed drain, curb wall, flush haunch, footpath or rock cut, must be reinstated 600mm (2 feet) from the outer edge of the track towards the centre line of the carriageway and all of the old asphalt removed from the inner edge and paved.

ii. Tracks at the centre of a lane would require the reinstatement of the tracks and the paving of the lane.

iii. Tracks that are excavated along the centre or within the proximity of the carriageway would require the reinstatement of the track and the paving of the full width of the road.

iv. Tracks that are excavated away from the road edge but are not at the centre of a lane would require the reinstatement of 600mm (2 ft.) outside of the inner and outer edge of the respective tracks et cetera.

v. Where the excavation of your tracks cause the other utility companies, for example the Barbados Water Authority, to remove replace or repair their services across the roads, you are responsible for the squaring of the cross cuts; compacting and paving with the required 75mm of hot rolled asphalt concrete to the existing riding surface level.

Philip Tudor

Deputy Chief Technical Officer (Operations)

For Permanent Secretary