Verge or footway 150 Finished road surface 125 Finished road surface 125 250x125 Polymer modified kerb friction course (PMFC) 50 Wearing course (Optional) 150 Base course . n 20/20 concrete backing i Road-base 150 m (See Note 3) Sub-base 150 Subgrade 20/20 concrete foundation 1:3 cement mortar PAVEMENT CROSS-SECTION Layers Material Thickness Polymer modified Bituminous friction course 30 Applications refer to RD/GN/011 and RD/GN/032 (non-structural layer) (Optional) Wearing course 40 Total thickness to be designed to RD/GN/042 and (i) min. 350 for Expressway, Trunk Road, and Base course Bituminous 65 Primary Distributor, or (ii) min. 280 for all other roads except low-volume roads Road base max. 395 (iii) min. 205 for low-volume roads Sub-base Granular Designed to RD/GN/042 THICKNESS OF PAVEMENT LAYERS Overlap (see Note 2) Cut back distance Prepared joint (See Note 1 ) D Notes: JOINTS IN BITUMINOUS MATERIALS LAYERS 1. Minimum cut back distance = 2 x D or 100 whichever is greater. 2. Minimum overlap between adjoining layers: 150 for joints longitudinal to carriageway. Original 500 for joints transverse to carriageway. C Include PMFC layer Jan 17 Signed 3. Where the crossfall of road surface is towards the kerb the Table for thickness revised to tally sub-base should be carried through to the edge of the B - Nov 13 with RD/GN/042 embankment or to the filter drain. Table for thickness revised July 11 4. Refer to the general specification for the nominal sizes of materials. A - 5. Kerb units shall be laid on 1 : 3 cement mortar not less than Former Drg. No. H1016/A June 94 - 10 mm thick and not more than 40 mm thick. with general revision 6. All dimensions are in millimetres. REF. REVISION SIGNATURE DATE HIGHWAYS DEPARTMENT TYPICAL BITUMINOUS REFERENCE DRAWING No. CAD RD/GN/042 PAVEMENT CONSTRUCTION SCALE H 1101C Diagrammatic.