Site Inspections
Site selection
Transport Scotland’s pavement management system, AMPS, was used to provide information on materials selected for the 2023 survey. The approximate site locations are shown in Figure 2-1.
A total of 49 sites were visited, which were nominally five years old, i.e. the actual age of the surface course ranged between 4.5 and 5.5 years. The age and material type for all the sites inspected is shown in Table 2-1. The table also includes an estimation of traffic stress based on road layout and type of traffic at the locus of the inspection. All sites inspected were allocated specific acronyms, e.g. IP1, IP2, etc., to retain supplier anonymity throughout the report. Three additional sites of interest were also visited at the request of Transport Scotland. These sites are discussed separately under section 4 and contained new materials or had been reported to be performing poorly.
| Site Ref. | Location | Type | Stress Level | Age (yrs.) |
|---|---|---|---|---|
| IP1 | M9 North Bound, West of Kirkliston | TS2010 | M | 5.2 |
| IP2 | M9 North Bound, North of Grangemouth | TS2010 | M | 5.2 |
| IP3 | M9 South Bound, East of Linlithgow | TS2010 | M | 5 |
| IP4 | M8 East Bound, River Almond | TS2010 | M | 5.2 |
| IP5 | A720 East Bound, Fairmilehead | TS2010 | M | 4.6 |
| IP6 | A1 North Bound, Dunbar | TS2010 | M/H | 4.6 |
| IP7 | A68 North of Pathead | TS2010 | L | 4.9 |
| IP8 | A68 East of Oxton | TS2010 | M | 5.3 |
| IP9 | A68 North of Earlston | TS2010 | L | 5 |
| IP10 | A7 South of Hawick | TS2010 | L/M | 4.9 |
| IP11 | A7 River Teviot | TS2010 | L | 5.4 |
| IP12 | A7 North Langholm | TS2010 | H | 5.2 |
| IP13 | A7 South Langholm | TS2010 | H | 5.2 |
| IP14 | A75 West of Annan | TS2010 | L | 5.4 |
| IP15 | A75 West of Cargenbridge | TS2010 | M | 5 |
| IP16 | A75 West of Twynholm | TS2010 | L | 4.8 |
| IP17 | A76 Kilpatrick | TS2010 | L | 5.1 |
| IP18 | A76 South of Cumnock | TS2010 | L | 4.6 |
| IP19 | A78 North of Ardrossan | TS2010 | L | 5.2 |
| IP20 | A78 Skermorlie | TS2010 | N/A | 5.4 |
| IP21 | A8 Greenock | TS2010 | M | 5.4 |
| IP22 | M8 West Bound North of Paisley | TS2010 | M | 4.5 |
| IP23 | A82 North of Inverbeg | CL942 | H | 5.2 |
| IP24 | A85 West of Tyndrum | CL942 | L | 5.2 |
| IP25 | A85 West of Dalmally | CL942 | L | 5.4 |
| IP26 | A85 South of Dunbeg | CL942 | M | 5.1 |
| IP27 | A828 West of Barcaldine | CL942 | M | 4.8 |
| IP28 | A828 North of Ballachulish | TS2010 | M | 4.5 |
| IP29 | A830 West of Glenfinnan | CL942 | M | 5.1 |
| IP30 | A82 West of Spean Bridge | TS2010 | L | 5 |
| IP31 | A82 South of Invergloy | CL942 | L | 4.5 |
| IP32 | A887 West of Glenmoriston | CL942 | L | 5.4 |
| IP33a/b | A887 West of Invermoriston | TS2010 | L/M | 5.3 |
| IP34 | A82 North of Drumnadrochit | TS2010 | L | 5.1 |
| IP35 | A96 West of Nairn | TS2010 | L | 4.6 |
| IP36a/b | A96 Nairn | TS2010 | M/H | 5.1 |
| IP37 | A96 North of Keith | TS2010 | L | 5.3 |
| IP38 | A96 North of Huntly | TS2010 | M | 4.6 |
| IP39 | A96 Hillhead | TS2010 | M | 5.2 |
| IP40a/b | A90 South of Ellon | TS2010 | L/H | 4.5 |
| IP41 | A90 East of Ellon | TS2010 | M | 5 |
| IP42 | A90 North Bound South of Brechin | TS2010 | M | 4.5 |
| IP43 | A90 South Bound Tarbrax | TS2010 | M | 4.5 |
| IP44 | A90 North Bound Petterden | TS2010 | M | 4.8 |
| IP45 | A90 North Bound Dundee | TS2010 | M | 4.8 |
| IP46 | A92 Letham | TS2010 | M | 4.6 |
| IP47 | A92 South of Letham | TS2010 | L | 5 |
| IP48 | A92 Cowdenbeath | TS2010 | M | 5.1 |
| IP49 | M90 North Bound Kelty | TS2010 | M | 4.8 |
Key
Clause 942: Thin surface course systems (MCHW 1,Series 900); TS2010: Stone mastic asphalt with polymer modified bitumen and added fibres (TSIA No 35, 2018).
Stress Level: L- Low stress site; M- Medium stress site; and H- High stress site.
Inspection method
The sites were assessed visually and ranked in accordance with the TRL Scottish Inspection Panel marking system (McHale et al., 2011). Full details of the method of inspection, including the meaning of each mark and defect suffix, are described in Appendix A.