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SPECIFICATION FOR THE REINSTATEMENT OF OPENINGS IN ROADS

S10 Compaction Requirements

S10.1 Introduction

1) All compaction equipment covered by this Specification shall be checked, adjusted, maintained and operated in accordance with working practices, maintenance schedules, operating procedures and vibrating frequencies recommended by the equipment manufacturer.

2) All equipment and operating procedures used for the compaction of all reinstatement materials laid above the surround to apparatus shall comply with the following relevant requirements:

S10.2 Reinstatement Materials

For all materials, compaction shall be carried out in accordance with the requirements of Appendix A2 and or A8, immediately after the material has been placed and spread.

S10.2.1 Unbound Granular and Cohesive Materials

1) All Class A Graded Granular Materials, Class B Granular Materials and Class C Cohesive/Granular Materials shall be compacted in accordance with the relevant requirements of Appendix A8, Table A8.1.

2) All Class D Cohesive Materials shall be compacted in accordance with the relevant requirements and restrictions of Appendix A8, Table A8.1.

3) Where access is restricted, including small excavations and trenches less than 200 mm wide, compaction shall be in accordance with the restricted access provisions of Appendix A8, Table A8.1.

S10.2.2 Alternative Reinstatement Materials

1) Certain Structural Materials for Reinstatements (SMRs) and Stabilised Materials for Fill (SMFs) may not require the full compaction specified in Appendix A8, Table A8.1 and may be damaged if compaction is continued. Appendix A9 deals with these materials. Such materials should be placed and compacted in accordance with the manufacturer's recommendations and with due regard to the requirements of Appendix A9.

2) Foamed concretes (FCRs) shall not be compacted or tamped unless specifically required by the manufacturer. Thereafter, such FCR materials shall be placed and compacted in accordance with the manufacturer's recommendations and with due regard to the requirements of Appendix A9.

S10.2.3 Bituminous Materials

1) All bituminous materials permitted by Appendix A2 shall be laid and compacted in accordance with the relevant requirements of Appendix A2, Tables A2.1 to A2.3 inclusive, and Appendix A8, section A8.3. Where access is restricted, including small excavations and trenches less than 200 mm wide, compaction shall be in accordance with the restricted access provisions of Appendix A8, Table A8.3.

2) The in-situ air void content for all bituminous materials as permitted in Appendix A2 shall comply with the requirements shown in Table S10.1. The in-situ air void content shall be calculated as the average from all results obtained and shall be determined in accordance with SHW Clause 937: sub-clauses 32 & 33. The overall accuracy of this test measurement is deemed to be 0.5%.

Table S10.1 - In-Situ Air Void Content Requirements

3) All surface course materials used at binder course level shall comply with the in-situ air void content requirement for the relevant surface course material.

4) To determine the in-situ air void content, the entire reinstatement shall be divided into notional units of 18 m ² area and a minimum of three core samples shall be extracted from each notional unit. For reinstatements up to 2 m ² area, a single core sample shall be extracted. All core samples shall be 100 mm minimum diameter, with no part of any core being within 75 mm of either the edge of the reinstatement or of any fixed feature within the reinstatement. The average void content shall be calculated for each notional unit, from all results obtained.

5) Unless agreed otherwise, all air void testing shall be carried out by a laboratory holding current UKAS accreditation for the specified test methods.

6) Where the prevailing weather conditions or other site circumstances are considered likely to mitigate against the successful laying and compaction of any surfacing materials and the achievement of the required in-situ air void content, consideration should be given to deferring the permanent surface reinstatement and, if necessary, to an agreed extension of the interim reinstatement period.

S10.2.4 Cementitious Materials

1) Pavement quality concrete, laid as the surface slab of road, footway, footpath or cycletrack reinstatements, shall be compacted using a proprietary vibrator, selected and operated in accordance with the manufacturer's recommendations. However, proprietary vibrators may be unsuitable for concrete sections less than 100 mm wide or less than 0.5 square metres in area. In such cases, as a minimum requirement, all concrete shall be thoroughly tamped, by hand.

2) Cement-bound granular materials, including CBM3 shall be compacted in accordance with the relevant requirements of Appendix A8, Table A8.1.

S10.2.5 Modular Surfacing Materials

Compaction equipment shall be operated in accordance with the manufacturer's instructions.

S10.3 Equipment Operation and Restrictions

1) All compaction equipment shall be used in accordance with the requirements of Appendix A8.

2) Additional guidance on compaction procedures and the maintenance of compaction equipment is included in Section NG10.6.

S10.3.1 Hand Rammers

Except as permitted in Sections S2.2.6, S10.2.2 and S10.2.4 (1), hand rammers shall be permitted to assist the initial placement of material only. For all materials, full compaction shall be applied, in accordance with the relevant requirements of Appendix A8.

S10.3.2 Percussive Rammers

Percussive rammers shall be permitted for the compaction of reinstatement materials, in accordance with the following requirements:

a) The nominal mass shall not be less than 10 kg.
b) The width of the foot shall not exceed 200 mm
c) The contact length of the foot shall not exceed 200 mm.

S10.3.3 Vibrotampers

Vibrotampers shall be permitted for the compaction of reinstatement materials, in accordance with the following requirements:

1) 50 kg Minimum Nominal Mass

a) The width of the foot shall not exceed 5 mm per kg of the nominal mass.
b) The contact length of the foot shall not exceed 350 mm nor be less than 175 mm.
c) The foot contact area shall not exceed 1000 sq. mm per kg of the nominal mass.
d) The mass of any extension leg shall not exceed 10% of the nominal mass.

2) 25 to 50 kg Nominal Mass - permitted in areas of restricted access only

a) The width of the foot shall not exceed 150 mm.
b) The contact length of the foot shall not exceed 200 mm.

S10.3.4 Vibrating Rollers

Vibrating rollers shall be permitted for the compaction of reinstatement materials, in accordance with the following requirements:

1) Single-Drum Vibrating Rollers

a) Single drum vibrating rollers shall include a mechanical means of applying vibration to the roll. Single-drum rollers without a specific vibration unit shall be considered to be single-drum deadweight rollers and shall not be permitted for reinstatement purposes.
b) The minimum mass of a single-drum vibrating roller shall be 1000 kg per metre width.

2) Twin-Drum Vibrating Rollers

a) Twin-drum vibrating rollers shall include two vibrating rolls. Twin-drum rollers in which only one roll vibrates shall be considered to be single-drum vibrating rollers.
b) The minimum mass of a twin-drum vibrating roller shall be 600 kg per metre width.

3) All Vibrating Rollers

a) The mass per metre width of a vibrating roller shall be calculated by dividing the total mass supported by the roll(s) by the total width of the roll(s).
b) Where existing roads, footways, footpaths or cycletracks may be marked or otherwise damaged by the use of heavy vibrating equipment, the Authority shall notify the Undertaker accordingly, whereupon the use of lower weight vibrating compaction equipment shall be agreed.

S10.3.5 Vibrating Plate Compactors

Vibrating plate compactors of 1400 kg per square metre minimum mass shall be permitted for the compaction of reinstatement materials.

S10.3.6 Other Compaction Equipment

Other compaction equipment, including machine-mounted compactors and all other compaction devices not specifically referenced within Appendix A8, may be permitted for the compaction of reinstatement materials, subject to the requirements of Section NG10 and agreement with the Authority.

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