CC 201 Pavement foundation construction

4.1 The construction subgrade surface modulus for each subgrade characteristic section shall be equal or greater than the design subgrade surface modulus specified in "Pavement foundation construction" in Section 1 of this document.

4.2 Verification shall be undertaken for the subgrade surface modulus for each subgrade characteristic section by measurement using one of the following devices: Dynamic cone penetrometer (DCP) (see requirements in Dynamic cone penetrometer (DCP) testing for subgrade assessment), Falling weight deflectometer (FWD) (see requirements in Falling weight deflectometer (FWD) testing for subgrade assessment) or Lightweight deflectometer (LWD) (see requirements in Lightweight deflectometer (LWD) testing for subgrade assessment).

4.3 The frequency of measurement of subgrade surface modulus shall be at least 10 tests at a maximum spacing of 60 m between each test, evenly spaced along each lane of prepared subgrade and staggered to the mid-point between adjacent lanes where multiple lanes are being tested (see figure 4.5 below) unless otherwise stated in CC 201/WSR/001.

4.4 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the measurement of the subgrade surface modulus.

4.5

4.6 The measurement of the construction subgrade surface modulus for each subgrade characteristic section shall be taken at formation level or at sub-formation level if capping is part of the pavement foundation design.

4.13 The following Documentation shall be submitted for the devices used to measure the subgrade surface modulus prior to the commencement of the construction of the pavement foundation: FWD or LWD annual calibration certificate.

5.1 Prior to construction of the overlying layers, the surface level of the capping shall be at the design level within the following tolerances: + 20 mm and - 30 mm, unless otherwise stated in CC 201/WSR/003.

5.2 Verification shall be undertaken for the surface level of the capping by measurement against the datum level on a grid of points not more than 2 m spacing transversely and not more than 10 m spacing longitudinally.

5.3 The frequency of measurement of surface levels shall be once prior to overlay.

5.4 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the measurement of the surface level of the capping.

5.5 Prior to construction of the overlying layers, the surface level of the subbase shall be at the design level subject to the relevant tolerances stated in table 5.6, unless otherwise stated in CC 201/WSR/003.

5.6

5.7 In any length of pavement, compliance shall be deemed to be met when not more than one of 10 consecutive measurements taken longitudinally or one in any transverse line, exceeds the tolerances permitted in table 5.6.

5.8 Verification shall be undertaken for the surface level of the subbase by measurement against the datum level on a grid of points not more than 2 m spacing transversely and not more than 10 m spacing longitudinally.

5.9 The frequency of measurement of surface levels shall be once prior to overlay.

5.10 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the measurement of the surface level of the subbase.

5.11 Prior to construction of pavement quality concrete layers, the longitudinal regularity of the subbase, measured as the difference between the surface and the underside of a straightedge placed parallel with the centre line of the road, shall be not more than 10 mm.

5.12 Verification shall be undertaken for the subbase longitudinal regularity in accordance with BS 8420 [Ref 31.N]using a straightedge of minimum 2 m length.

5.13 The frequency of measurement of subbase longitudinal regularity shall be one per 100 m.

5.14 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the measurement of the longitudinal regularity of the subbase.

5.15 Verification for the longitudinal regularity of the subbase by measurement shall be undertaken by an accredited testing laboratory in compliance with "Accredited laboratory" in Section 16 of GC 101 [Ref 19.N].

5.16 For unbound and hydraulically bound materials, when rectification is undertaken, the area treated shall be at least 20 m long and 2 m wide.

5.17 For bituminous materials, when rectification is undertaken, the area treated shall be at least 5 m long and the full width of the pavement laid in one operation.

6.1 Unbound capping shall be as specified in CC 201/WSR/004.

6.2 Unbound capping shall be constructed with materials complying with class 6F1, 6F2, 6F3, 6F4, 6F5 or 6S.

6.3 Unbound capping materials shall comply with "Earthworks materials" in Section 2 of CC 601 [Ref 16.N].

6.16 Unbound capping shall comply with Limiting distances of earthworks materials with elevated sulfur species in "General earthworks construction" in Section 5 of CC 601 [Ref 16.N].

6.17 The grading of unbound capping materials shall be compliant with BS 1377-2 [Ref 32.N]or BS EN 13285 [Ref 54.N].

6.18 The grading of unbound capping materials shall meet the performance characteristics as stated in table 6.19.

6.19

6.20 Verification shall be undertaken for the grading of site won unbound capping by sampling and testing in accordance with BS 1377-2 [Ref 32.N].

6.21 The frequency of sampling and testing shall be once per week of production or once per 5000 tonnes, whichever is most frequent.

6.22 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the grading of site won unbound capping.

6.23 Verification shall be undertaken for the grading of recycled (site won or imported) and imported unbound capping by sampling and testing in accordance with BS EN 13285 [Ref 54.N].

6.24 The frequency of sampling and testing shall be once per week of production or once per 5000 tonnes, whichever is most frequent.

6.25 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the grading of recycled (site won or imported) and imported unbound capping.

6.26 Verification for grading of unbound capping shall be undertaken by an accredited testing laboratory in compliance with "Accredited laboratory" in Section 16 of GC 101 [Ref 19.N].

6.27 The asphalt content and maximum bitumen content of unbound capping materials shall be as stated in table 6.27.

6.28 Verification shall be undertaken for the asphalt content of unbound capping materials by testing in accordance with BS EN 933-11 [Ref 39.N].

6.29 The frequency of asphalt content testing shall be once per week of production or once per 5000 tonnes, whichever is most frequent.

6.30 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of asphalt content of unbound capping materials.

6.31 Verification shall be undertaken for the bitumen content of unbound capping materials with more than 20% reclaimed asphalt content by testing in accordance with BS EN 12697-1 [Ref 7.N] or BS EN 12697-39 [Ref 8.N].

6.32 The frequency of bitumen content testing shall be once per material.

6.33 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of bitumen content of unbound capping materials.

6.34 Verification for asphalt content and bitumen content shall be undertaken by an accredited testing laboratory in compliance with "Accredited laboratory" in Section 16 of GC 101 [Ref 19.N].

6.35 The size fraction of material class 6S (imported) passing the 0.425 mm size test sieve shall be non-plastic.

6.36 Verification shall be undertaken for the plasticity of the fraction passing the 0.425 mm test sieve for material class 6S (imported) by testing in accordance with BS 1377-2 [Ref 32.N].

6.37 The frequency of plasticity testing shall be once per mixture type.

6.38 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of plasticity of material class 6S (imported).

6.39 Verification for the plasticity by testing shall be undertaken by an accredited testing laboratory in compliance with "Accredited laboratory" in Section 16 of GC 101 [Ref 19.N].

6.40 Optimum water content of 6F1, 6F2 and 6F3 unbound capping materials shall be determined.

6.41 Verification shall be undertaken for the optimum water content of 6F1 and 6F2 unbound capping materials by testing in accordance with the vibrating hammer method in BS 1377-2 [Ref 32.N].

6.42 The frequency of optimum water content testing shall be once per mixture.

6.43 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of optimum water content of 6F1 and 6F2 unbound capping materials.

6.44 Verification shall be undertaken for the optimum water content of 6F3 unbound capping material by testing in accordance with BS 1377-2 [Ref 32.N], the oven dry method by using a reduced temperature of 45 to 50°C.

6.45 The frequency of optimum water content testing shall be once per mixture.

6.46 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of optimum water content of 6F3 unbound capping materials.

6.47 Laboratory dry density and optimum water content of 6F4 and 6F5 unbound capping materials shall be determined.

6.48 Verification shall be undertaken for the laboratory dry density and optimum water content of 6F4 and 6F5 unbound capping materials by testing in accordance with BS EN 13285 [Ref 54.N].

6.49 The frequency of laboratory dry density and optimum water content testing shall be once per mixture.

6.50 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of laboratory dry density and optimum water content of 6F4 and 6F5 unbound capping materials.

6.51 Verification for dry density and water content by testing shall be undertaken by an accredited testing laboratory in compliance with "Accredited laboratory" in Section 16 of GC 101 [Ref 19.N].

6.57 The following Documentation shall be submitted for site won unbound capping materials (6F1, 6F2 and 6F3) prior to the commencement of the capping construction: optimum water content report.

6.58 The requirements for "Documentation" in Section 2 of GC 101 [Ref 19.N] shall apply to the optimum water content report.

6.59 The following Documentation shall be submitted for imported unbound capping materials (6F4 and 6F5) prior to the commencement of the capping construction: dry density and optimum water content report.

6.60 The requirements for "Documentation" in Section 2 of GC 101 [Ref 19.N] shall apply to the dry density and optimum water content report.

6.61 Installed unbound capping shall comply with "Foundation surface levels, regularity and rectification" in Section 5 of this document.

6.62 The minimum compacted layer thickness of 6F1, 6F2, 6F3, 6F4 and 6F5 unbound capping shall be 110 mm.

6.63 The minimum layer thickness of 6S unbound capping shall be 50 mm.

6.64 The maximum nominal thickness of unbound capping material 6F3 installed in one layer shall be 200 mm.

6.65 The maximum nominal thickness of unbound capping materials 6F1, 6F2, 6F4 and 6F5 installed in one layer shall be 250 mm.

6.66 The lowest layer of unbound capping layers of unequal thickness shall be the thickest layer.

6.67 Site won unbound capping materials (6F1 and 6F2) and 6F3 shall be laid and compacted at + 0% / - 2% of the declared optimum water content.

6.68 Verification shall be undertaken for the water content of site won unbound capping materials (6F1 and 6F2) by testing in accordance with BS 1377-2 [Ref 32.N].

6.69 The frequency of water content testing shall be once per week of production or once per 5000 tonnes, whichever is most frequent.

6.70 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of water content of site won unbound capping.

6.71 Verification shall be undertaken for the water content of imported unbound capping materials (6F3) by testing in accordance with the oven dry method of BS 1377-2 [Ref 32.N], by using a reduced temperature of 45 to 50 °C.

6.72 The frequency of water content testing shall be once per week of production or once per 5000 tonnes, whichever is most frequent.

6.73 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of water content of 6F3 unbound capping.

6.74 Imported unbound capping materials (6F4 and 6F5) shall be laid and compacted at + 0% / - 2% of the declared optimum water content.

6.75 Verification shall be undertaken for the water content of imported unbound capping materials (6F4 and 6F5) by testing in accordance with BS EN 1097-5 [Ref 42.N].

6.76 The frequency of water content testing shall be once per week of production or once per 5000 tonnes, whichever is most frequent.

6.77 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of water content of 6F4 and 6F5 unbound capping.

6.78 Verification for water content shall be undertaken by an accredited testing laboratory in compliance with "Accredited laboratory" in Section 16 of GC 101 [Ref 19.N].

6.79 Trafficking of filter layers constructed with 6S material shall be limited to the traffic directly engaged in the depositing, spreading and compaction of the 6S material.

6.80 The leading edge of the 6S material shall not extend more than 100 m beyond the leading edge of the subbase layer.

6.81 Compaction of unbound capping (6F1, 6F2, 6F3, 6F4 and 6F5) shall be carried out by a method specified in table 6.81, unless it is demonstrated at site trials that a state of compaction achieved by an alternative method is equivalent to or better than that using the specified method.

6.82 Where more than one class of material is being used, capping shall be compacted with plant operating as if only the material which requires the greater compactive effort is being compacted.

6.83 The minimum number of passes N is the minimum number of times that each point on the surface of the layer being compacted shall be traversed by the item of compaction plant in its operating mode, or struck by power rammers or falling weight compactors.

6.84 The compaction plant in table 6.81 shall be categorised in terms of static mass.

6.85 The mass per metre width of roll in table 6.81 shall be the total mass on the roll divided by the total roll width.

6.86 Where a smooth wheeled roller has more than one axle, the category of the machine in table 6.81 shall be determined on the basis of the axle giving the highest value of mass per metre width.

6.87 A grid roller shall be a machine with a compacting roll or rolls constructed of heavy steel mesh of square pattern.

6.88 A deadweight tamping roller shall be a machine with a roll or rolls from which ‘feet’ project, where the projected end area of each 'foot' exceeds 0.01 m² and sum of the areas of the 'feet' exceeds 15% of the area of the cylinder swept by the ends of the 'feet'.

6.89 If only one tamping roll of a deadweight tamping roller traverses each point on the surface of the layer on any one pass of the machine, the minimum number of passes shall be twice the number given in table 6.81.

6.90 For pneumatic-tyred rollers, the mass per wheel shall be the total mass of the roller divided by the number of wheels.

6.91 In assessing the number of passes of pneumatic-tyred rollers, the effective width shall be the sum of the widths of the individual wheel tracks together with the sum of the spacings between the wheel tracks provided that each spacing does not exceed 230 mm.

6.92 Where the spacings exceed 230 mm the effective width of pneumatic-tyred rollers shall be the sum of the widths of the individual wheel tracks only.

6.93 A vibratory tamping roller, which can be self-propelled or towed, shall be a machine having a means of applying mechanical vibration to one or more rolls. The rolls have projected feet where the height of each foot exceeds 10% radius of the roll drum, the projected end area of each foot exceeds 0.1% of the roll drum surface area, and the sum of the areas of the feet exceeds 10% of the area of the cylinder swept by the ends of the feet.

6.94 The requirements for the operation of vibratory tamping rollers shall be the same as those stated for vibratory rollers except that vibratory tamping rollers operating without vibration will be classified as dead weight tamping rollers.

6.95 Vibratory rollers shall be self-propelled or towed smooth-wheeled rollers having means of applying mechanical vibration to one or more rolls.

6.96 The number of passes in table 6.81 for vibratory rollers with a self-propelled machine with mechanical transmission are based on operation of the machine in the lowest gear. If higher gears are used an increased number of passes shall be provided in proportion to the increase in speed of travel.

6.97 The number of passes in table 6.81 for vibratory rollers for a towed machine, or a self propelled machine with hydrostatic transmission are based on a speed of 1.5 to 2.5 km/h. If higher speeds are used an increased number of passes shall be provided in proportion to the increase in speed of travel.

6.98 Where the mechanical vibration is applied to two rolls in tandem, the minimum number of passes shall be half the number given in table 6.81 for the mass per metre width of one vibrating roll.

6.99 Where one roll of a vibratory roller differs in mass per metre width from the other, the number of passes shall be calculated as for the roll with the smallest value or by treating the machine as having a single vibrating roll with a mass per metre width equal to that of the roll with the higher value.

6.100 Vibratory rollers shall be operated with their vibratory mechanism operating only at the frequency of vibration recommended by the manufacturers.

6.101 Where more than one amplitude setting is available and/or a range of frequencies is recommended, the machine shall be operated at the maximum amplitude setting and at the maximum recommended frequency for that setting.

6.102 Vibratory rollers shall be equipped or provided with devices indicating the frequency at which the mechanism is operating and the speed of travel.

6.103 Vibrating plate compactors shall have a base plate which is attached to a source of vibration consisting of one or two eccentrically weighted shafts.

6.104 The mass per square metre of base plate of a vibrating plate compactors shall be calculated by dividing the total mass of the machine in its working condition by its area in contact with compacted material.

6.105 Vibrating plate compactors shall be operated at the frequency of vibration recommended by the manufacturer.

6.106 Where vibrating plate compactors are operated at travelling speeds higher than 1 km/h, the number of passes shall be increased in proportion to the increase in speed of travel.

6.107 Vibro-tampers shall be machines in which an engine-driven reciprocating mechanism acts on a spring system through which oscillations are set up in a base plate.

6.108 Power rammers shall be machines which are actuated by explosions in an internal combustion cylinder, each explosion being controlled manually by the operator.

6.109 Dropping weight compactors shall be machines in which a dead weight is dropped from a controlled height using a hoist mechanism and they include self-propelled machines with mechanical traversing mechanisms capable of compacting soil in trenches and close to structures.

6.110 In the case of power rammers and dropping-weight compactors one pass shall be counted as one strike applied by the compacting shoe.

6.111 Where combinations of different types or categories of plant are used, the depth of layer shall be that for the type of plant requiring the least depth of layer.

6.112 Where combinations of different types or categories of plant are used, the number of passes shall be that for the type of plant requiring the greatest number of passes.

6.113 On completion of compaction and prior to construction of the overlaying layers, the surface of any layer of unbound capping shall be free from cracks, loose material, potholes, ruts or other defects.

6.114 Performance pavement foundations shall comply with "Performance pavement foundation testing" in Section 13 of this document.

7.1 Bound capping shall be as specified in CC 201/WSR/005.

7.2 Chemical analysis shall be as specified in CC 201/WSR/005.

7.3 Bound capping for restricted foundations shall be constructed with materials complying with class 9A, 9B, 9C, 9D, 9E or 9F.

7.4 Bound capping for performance foundations shall be constructed with constituents complying with class 9P.

7.5 Materials to be stabilised with cement shall comply with class 6E, 7F or 7G.

7.6 Materials to be stabilised with lime shall comply with class 7E.

7.7 Materials to be stabilised with lime and cement shall comply with class 6R or 7I.

7.8 Materials classed as 6E, 6R, 7E, 7F, 7G and 7I shall comply with "Earthworks materials" in Section 2 of CC 601 [Ref 16.N].

7.9 Site won natural aggregates classed as 6E, 6R, 7E, 7F, and 7I to be stabilised to form bound capping shall meet the performance characteristics as stated in table 7.9.

7.10 Verification shall be undertaken for the water content of site won materials for stabilisation by testing in accordance with BS 1377-2 [Ref 32.N].

7.11 The frequency of water content testing shall be once per 400 tonnes unless otherwise stated in CC 201/WSR/005.

7.12 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of water content of site won materials for stabilisation to form bound capping.

7.13 Verification shall be undertaken for the liquid limit of site won materials for stabilisation by testing in accordance with BS 1377-2 [Ref 32.N].

7.14 The frequency of liquid limit testing shall be daily.

7.15 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of liquid limit of site won materials for stabilisation to form bound capping.

7.16 Verification shall be undertaken for the plasticity of site won materials for stabilisation by testing in accordance with BS 1377-2 [Ref 32.N].

7.17 The frequency of plasticity testing shall be daily.

7.18 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of plasticity of site won materials for stabilisation to form bound capping.

7.19 Verification shall be undertaken for the organic matter of site won materials for stabilisation by testing in accordance with BS 1377-3 [Ref 33.N].

7.20 The frequency of organic matter testing shall be twice weekly unless otherwise stated in CC 201/WSR/005.

7.21 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of organic matter of site won materials for stabilisation to form bound capping.

7.22 Verification shall be undertaken for the water soluble sulfate and oxidisable sulfides content of site won materials for stabilisation by testing in accordance with BS EN 1744-1 [Ref 37.N].

7.23 The frequency of water soluble sulfate and oxidisable sulfides content testing shall be twice weekly with a minimum of five samples per mixture, using the two higher values to obtain the mean value for comparison with the limiting values. If ten or more results are available the mean is to be calculated using the highest 20% of the results unless otherwise stated in CC 201/WSR/005.

7.24 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of water soluble sulfate and oxidisable sulfides of site won materials for stabilisation to form bound capping.

7.25 Verification shall be undertaken for the total potential sulfate content of 7E, 7F and 7I site won materials for stabilisation by testing total sulfur (%S) in accordance with BS EN 1744-1 [Ref 37.N], calculating the total potential sulfate expressed as %SO4 (total potential sulfate = total sulfur x 3).

7.26 The frequency of total potential sulfate content testing shall be twice weekly with a minimum of five samples per mixture, using the two higher values to obtain the mean value for comparison with the limiting values. If ten or more results are available the mean is to be calculated using the highest 20% of the results unless otherwise stated in CC 201/WSR/005.

7.27 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of total sulfur to determine the total potential sulfate content of 7E, 7F and 7I site won materials for stabilisation to form bound capping.

7.28 Verification shall be undertaken for the SMC of site won chalk for stabilisation by testing in accordance with BS 1377-2 [Ref 32.N].

7.29 The frequency of SMC testing shall be twice weekly.

7.30 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of SMC of site won chalk for stabilisation to form bound capping.

7.31 Verification shall be undertaken for the IDD of site won chalk for stabilisation by testing in accordance with BS 1377-2 [Ref 32.N].

7.32 The frequency of IDD testing shall be twice weekly.

7.33 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of the IDD of site won chalk for stabilisation to form bound capping.

7.34 Verification shall be undertaken for the MCV of site won materials for stabilisation by testing in accordance with BS 1377-2 [Ref 32.N].

7.35 The frequency of MCV testing shall be once per 400 tonnes.

7.36 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of MCV of site won materials for stabilisation to form bound capping.

7.37 Verification for the water content, liquid limit, fines quality, organic matter, water soluble sulfate, oxidisable sulfides and total potential sulfate content, SMC, IDD, MCV and uniformity coefficient shall be undertaken by an accredited testing laboratory in compliance with "Accredited laboratory" in Section 16 of GC 101 [Ref 19.N].

7.38 Imported natural aggregates, recycled aggregates and manufactured aggregates classed as 6E, 6R and 7G to be stabilised to form bound capping shall be compliant with BS EN 13242 [Ref 2.N].

7.39 The aggregates shall meet the performance characteristics as stated in table 7.41.

7.40 The requirements of "Designated standards" in Section 10 of GC 101 [Ref 19.N] shall apply to imported natural aggregates, recycled aggregates and manufactured aggregates for stabilisation to form bound capping.

7.41

7.42 Cement shall be compliant with BS EN 197-1 [Ref 11.N].

7.43 The cement for bound capping shall meet the following performance characteristics: CEM I, CEM II, CEM III, CEM IV or CEM V.

7.44 The requirements of "Designated standards" in Section 10 of GC 101 [Ref 19.N] shall apply to the cement for bound capping.

7.45 Portland-composite cement CEM II/C-M and Composite cement CEM VI for bound capping shall be compliant with BS EN 197-5 [Ref 12.N].

7.46 The Portland-composite cement CEM II/C-M and Composite cement CEM VI for bound capping shall meet the following performance characteristics: Type CEM II/C-M or CEM VI.

7.47 Lime shall be compliant with BS EN 459-1 [Ref 9.N].

7.48 The lime for bound capping shall meet the following performance characteristics: quicklime P4 or hydrated lime.

7.49 The requirements of "Designated standards" in Section 10 of GC 101 [Ref 19.N] shall apply to the lime for bound capping.

7.50 Fly ash, slag, hydraulic road binders and blends shall be compliant with BS EN 16907-4 [Ref 17.N].

7.51 Water shall not contain components which adversely affect the hardening and the performance of the bound capping materials.

7.52 Grading of materials to be stabilised to form bound capping shall be compliant with BS 1377-2 [Ref 32.N]or BS EN 13285 [Ref 54.N].

7.53 The grading of materials to be stabilised to form bound capping shall meet the performance characteristics as stated in table 7.51.

7.54

7.55 Verification shall be undertaken for the grading of site won material to be stabilised to form bound capping by sampling and testing in accordance with BS 1377-2 [Ref 32.N].

7.56 The frequency of sampling and testing shall be once per 400 tonnes.

7.57 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the grading of site won material to be stabilised to form bound capping.

7.58 Verification shall be undertaken for the grading of imported material to be stabilised to form bound capping by sampling and testing in accordance with BS EN 13285 [Ref 54.N].

7.59 The frequency of sampling and testing shall be once per 400 tonnes.

7.60 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the grading of imported material to be stabilised to form bound capping.

7.61 Verification for grading shall be undertaken by an accredited testing laboratory in compliance with "Accredited laboratory" in Section 16 of GC 101 [Ref 19.N].

7.62 The uniformity coefficient of 7F site won materials shall be 5.

7.63 Verification shall be undertaken for the uniformity coefficient of 7F site won materials for stabilisation defined as the ratio of the particle diameters D₆₀ to D₁₀ on the particle-size distribution curve, where D₆₀ is the particle diameter at which 60% of the soil by weight is fine and D₁₀ is the particle diameter at which 10% of the soil by weight is finer.

7.64 The frequency of uniformity coefficient testing shall be once per 400 tonnes.

7.65 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of uniformity coefficient of 7F site won materials for stabilisation to form bound capping.

7.66 The following Documentation shall be submitted for bound capping binders prior to the commencement of bound capping construction: binders certificate of conformity.

7.67 The requirements for "Documentation" in Section 2 of GC 101 [Ref 19.N] shall apply to the binders certificates.

7.111 Installed bound capping shall comply with "Foundation surface levels, regularity and rectification" in Section 5 of this document.

7.112 The minimum compacted layer thickness shall be 130 mm.

7.113 The maximum compacted layer thickness shall be 280 mm.

7.114 Cement stabilisation and cement and lime stabilisation shall not be undertaken when the shade temperature is below 3 °C unless on a rising thermometer above 0 °C.

7.115 Lime stabilisation shall only be carried out from March to the end of September.

7.116 Lime stabilisation shall not be undertaken when the shade temperature is below 7 °C.

7.117 Cement stabilisation and cement and lime stabilisation shall cease in case of inclement weather and any placed material compacted immediately.

7.118 Binder spreading shall be carried out in a manner and under conditions to avoid the binder being blown from the site onto adjacent land or property.

7.119 The plant used for stabilisation shall be in accordance with BS EN 16907-4 [Ref 17.N] in-situ mixing.

7.120 The pulverising and mixing process of Class 9A, 9B, 9C and 9F material shall be such that 95% of the silt and clay fraction of the material is reduced to particles or lumps passing a BS 28 mm sieve.

7.121 The pulverising and mixing process of the Class 9E or 9D material shall be such that 95% of the material is reduced to particles or lumps passing a BS 28 mm sieve.

7.122 Verification shall be undertaken for pulverising and mixing process of bound capping materials by passing the dry material through a BS 28 mm sieve.

7.123 The frequency of checking the pulverising and mixing process shall be 1 per lane width per 200 m length.

7.124 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the checking of pulverising and mixing process of bound capping.

7.125 The degree of pulverisation for Class 9A, 9C and 9F materials shall be P₆₀ before stabilisation.

7.126 The degree of pulverisation for Class 9B, 9D and 9E materials shall be P₃₀ before stabilisation.

7.127 Verification shall be undertaken for the degree of pulverisation of cement stabilised bound capping by testing in accordance with BS EN 13286-48 [Ref 46.N].

7.128 The frequency of degree of pulverisation testing shall be 1 per lane width per 200 m length.

7.129 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of pulverisation of bound capping.

7.130 The minimum overlap between adjacent passes of the stabilising machine shall be 150 mm.

7.131 Where a subsequent layer of material is placed on a layer previously stabilised the tines or blades of the stabilising machine shall be set so that they cut into the previously stabilised layer below by at least 20 mm.

7.132 When lime is used, the layer shall receive at least two passes of the stabilising machine to pulverise and mix the lime and soil.

7.133 The surface of the layer stabilised with lime shall be sealed with one pass of a smooth wheeled roller having a mass per metre width of roll of not less than 2700 kg or a pneumatic tyred roller of not less than 1000 kg per wheel.

7.134 After sealing the layer stabilised with lime, the process shall be interrupted by a period of not less than 24 hours and not greater than 72 hours, to enable the lime to react with the soil.

7.135 At the end of this period the layer stabilised with lime shall receive at least one more pass of the stabilising machine until compliance with the degree of pulverisation requirement is achieved (95% of the silt and clay fraction of the 9F material is reduced to particles or lumps passing 28 mm sieve; and 95% of the 9D or 9E material is reduced to particles or lumps passing 28 mm sieve).

7.136 For lime and cement stabilisation, the material previously mixed with lime shall be stabilised with cement in a single layer or in layers of the same compacted thickness as for the lime mixed material layers.

7.174 Performance pavement foundations shall comply with "Performance pavement foundation testing" in Section 13 of this document.

8.1 Unbound mixtures shall be as specified in CC 201/WSR/006.

8.2 Aggregates for unbound mixtures shall be compliant with BS EN 13242 [Ref 2.N].

8.3 The aggregates for unbound mixtures shall meet the performance characteristics as stated in table 8.8a.

8.4 The requirements of "Designated standards" in Section 10 of GC 101 [Ref 19.N] shall apply to aggregates for unbound mixtures.

8.5 The recycled coarse aggregates and recycled crushed concrete for unbound mixtures shall be compliant with BS EN 13242 [Ref 2.N].

8.6 The recycled coarse aggregates and recycled crushed concrete for unbound mixtures shall meet the performance characteristics as stated in table 8.8a and 8.8b.

8.7 The requirements of "Designated standards" in Section 10 of GC 101 [Ref 19.N] shall apply to the recycled coarse aggregates and recycled crushed concrete for unbound mixtures.

8.8

E/8.9 The quality control procedure for recycled coarse aggregate or recycled concrete aggregate used in unbound mixtures shall be in accordance with the WRAP Quality Protocol [Ref 55.N].

8.10 The results of all quality control checks carried out on recycled coarse aggregate or recycled concrete aggregate used in unbound mixtures shall be compiled in accordance with the quality control procedure for recycled coarse aggregate or recycled concrete aggregate used in unbound mixtures.

8.11 Unbound mixtures shall meet the requirements from table 8.11.

8.12 Verification shall be undertaken for the determination of the water-soluble sulfate, total sulfur, acid soluble sulfides and oxidisable sulfide of unbound mixtures by testing in accordance with BS EN 1744-1 [Ref 37.N].

8.13 The frequency of water soluble sulfate, total sulfur, acid soluble sulfides and oxidisable sulfide testing shall be a minimum of five samples per mixture, using the two higher values to obtain the mean value for comparison with the limiting values. If ten or more results are available the mean is to be calculated using the highest 20% of the results.

8.14 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of water-soluble sulfate, including the pH, total sulfur, acid soluble sulfides and oxidisable sulfide of unbound mixtures.

8.15 Verification for the determination of the water-soluble sulfate, total sulfur, acid soluble sulfides and oxidisable sulfide of the unbound mixtures by testing shall be undertaken by an accredited testing laboratory in compliance with "Accredited laboratory" in Section 16 of GC 101 [Ref 19.N].

8.46 Verification shall be undertaken for the grading and fines content of unbound mixtures by sampling and testing in accordance with BS EN 933-1 [Ref 40.N].

8.47 The frequency of sampling and testing shall be once per week of production or 1 per 5000 tonnes, whichever is most frequent.

8.48 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the grading and fines content of unbound mixtures.

8.49 Verification for grading and fines content of unbound mixtures by sampling and testing shall be undertaken by an accredited testing laboratory in compliance with "Accredited laboratory" in Section 16 of GC 101 [Ref 19.N].

8.50 Verification shall be undertaken for the plasticity of the fraction passing the 0.425 mm test sieve for unbound mixtures by testing in accordance with BS 1377-2 [Ref 32.N].

8.51 The frequency of plasticity testing shall be one per mixture type.

8.52 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of plasticity of unbound mixtures.

8.53 Verification for the plasticity of unbound mixtures by testing shall be undertaken by an accredited testing laboratory in compliance with "Accredited laboratory" in Section 16 of GC 101 [Ref 19.N].

8.54 Verification shall be undertaken for the recovered bitumen content of the asphalt in Type 4 unbound mixtures by testing in accordance with BS EN 12697-1 [Ref 7.N].

8.55 The frequency of recovered bitumen content testing shall be for each mixture.

8.56 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of recovered bitumen of Type 4 unbound mixtures.

8.57 Verification for the recovered bitumen content of the asphalt in Type 4 unbound mixtures by testing shall be undertaken by an accredited testing laboratory in compliance with "Accredited laboratory" in Section 16 of GC 101 [Ref 19.N].

8.58 The following Documentation shall be submitted for Type 2 and Type 4 unbound mixtures prior to the commencement of the construction of the subbase: optimum water content test reports.

8.59 The requirements for "Documentation" in Section 2 of GC 101 [Ref 19.N] shall apply to the optimum water content test reports.

8.60 The following Documentation shall be submitted for unbound mixtures incorporating manufactured aggregates other than air-cooled blast furnace slag and steel slag prior to the commencement of subbase construction: aluminium particle size test report including: the name and location of the sample source; date of sampling; mass of test portion (kg); date of test; number of aluminium particles retained on the 14 mm sieve; and description of any retained particles.

8.61 Installed unbound mixtures in subbases shall comply with "Foundation surface levels, regularity and rectification" in Section 5 of this document.

8.62 Type 2 and Type 4 unbound mixtures shall be laid and compacted at a water content within the range 1% above to 2% below the declared value of optimum water content.

8.63 The water content of Type 4 unbound mixtures shall be determined by oven drying at a reduced temperature setting of 45 ºC to 50 ºC.

8.64 Verification shall be undertaken for the water content of Type 2 and Type 4 unbound mixtures by testing in accordance with BS EN 1097-5 [Ref 42.N].

8.65 The frequency of water content testing shall be daily.

8.66 The requirements for "Verification" in Section 14 of GC 101 [Ref 19.N] shall apply to the testing of the water content of Type 2 and Type 4 unbound mixtures.

8.67 Verification for the water content of Type 2 and Type 4 unbound mixtures by testing shall be undertaken by an accredited testing laboratory in compliance with "Accredited laboratory" in Section 16 of GC 101 [Ref 19.N].

8.68 Unbound mixtures shall not be used in a frozen condition.

8.69 Unbound mixtures shall not be laid on any surface which is frozen or covered with ice.

8.70 The maximum nominal thickness of unbound mixtures installed in one layer shall be 225 mm, unless otherwise stated in CC 201/WSR/006.

8.71 The minimum compacted layer thickness of unbound mixtures, when laid in multiple layers, shall be 110 mm.

8.72 The lowest layer of unbound mixtures layers of unequal thickness shall be the thickest layer.

8.73 Compaction of unbound mixtures shall be carried out by a method specified in table 8.73, unless it is demonstrated at site trials that a state of compaction achieved by an alternative method is equivalent to or better than that using the specified method.

8.74 The number of passes shall be the number of times that each point on the surface of the layer being compacted is traversed by the item of compaction plant in its operating mode (or struck, in the case of power rammers).

8.75 The compaction plant shall be categorised in terms of static mass.

8.76 The mass per metre width of roll shall be the total mass divided by the total roll width.

8.77 For smooth wheeled rollers with more than one axle, the mass per metre width of roll shall be categorised based on the axle giving the highest value of mass per metre width.

8.78 For pneumatic-tyred rollers the mass per wheel shall be the total mass of the roller divided by the number of wheels.

8.79 In assessing the number of passes of pneumatic-tyred rollers the effective width shall be the sum of the widths of the individual wheel tracks together with the sum of the spacings between the wheel tracks provided that each spacing does not exceed 230 mm.

8.80 Where the spacings exceed 230 mm the effective width of pneumatic-tyred rollers shall be the sum of the widths of the individual wheel tracks only.

8.81 Vibratory rollers shall be self-propelled or towed smooth-wheeled rollers having means of applying mechanical vibration to one or more rolls.

8.82 The number of passes in table 8.73 for vibratory rollers with a self-propelled machine with mechanical transmission are based on operation of the machine in the lowest gear. If higher gears are used an increased number of passes shall be provided in proportion to the increase in speed of travel.

8.83 The number of passes in table 8.73 for vibratory rollers for a towed machine, or a self propelled machine with hydrostatic transmission are based on a speed of 1.5 to 2.5 km/h. If a higher speeds are used an increased number of passes shall be provided in proportion to the increase in speed of travel.

8.84 Where the mechanical vibration is applied to two rolls in tandem, the minimum number of passes shall be half the number given in table 8.73 for the mass per metre width of one vibrating roll.

8.85 Where one roll of a vibratory roller differs in mass per metre width from the other, the number of passes shall be calculated as for the roll with the smallest value or by treating the machine as having a single vibrating roll with a mass per metre width equal to that of the roll with the higher value.

8.86 Vibratory rollers shall be equipped or provided with devices indicating the frequency at which the mechanism is operating and the speed of travel.

8.87 Vibrating plate compactors shall have a base plate which is attached to a source of vibration consisting of one or two eccentrically-weighted shafts.

8.88 The mass per square metre of the base plate of a vibrating plate compactor shall be calculated by dividing the total mass of the machine in its working condition by its area in contact with compacted material.

8.89 Vibrating plate compactors shall be operated at the frequency of vibration recommended by the manufacturer.

8.90 Where vibrating plate compactors are operated at travelling speeds higher than 1 km/h, the number of passes shall be increased in proportion to the increase in speed of travel.

8.91 Vibro-tampers shall be machines in which an engine driven reciprocating mechanism acts on a spring system, through which oscillations are set up in a base plate.

8.92 Power rammers shall be machines which are actuated by explosions in an internal combustion cylinder; each explosion being controlled manually by the operator. One pass of a power rammer is counted when the compacting shoe has made one strike.

8.93 Where combinations of different types or categories of plant are used, the number of passes shall be such proportion of the number in table 8.73 as will together produce the same total compactive effort as any one operated singly.

8.94 On completion of compaction and prior to construction of the overlaying layers, the surface of any layer of material shall be free from movement under construction plant and from ridges, cracks, loose material, potholes, ruts or other defects.

8.95 When a trafficking trial is carried out, it shall comply with the trafficking trial requirements in "Performance pavement foundation testing" in Section 13 of this document.

8.96 Verification of unbound mixtures in performance pavement foundations shall comply with "Performance pavement foundation testing" in Section 13 of this document.

9.1 Hydraulically bound mixtures (HBM) shall be as specified in CC 201/WSR/007.

9.37 The following Documentation shall be submitted for HBM binders prior to the commencement of HBM layer construction: binders certificate of conformity.

9.38 The requirements for "Documentation" in Section 2 of GC 101 [Ref 19.N] shall apply to the binders certificates.