1. Introduction
The purpose of this verification report is to document the compliance of the newly constructed asphalt roadway with the design specifications, applicable standards, and performance criteria set forth in the contract documents. The report summarizes field observations, laboratory test results, and nondestructive testing (NDT) findings that collectively demonstrate the quality and durability of the pavement system.
2. Project Overview
Location: Milepost 12.518.0, Highway 78, County A
Construction Period: 15January2026 28April2026
Design Classification: TypeIII, Flexible Pavement
Design Thickness: 10cm surface course, 12cm base course, 30cm subbase
Materials: Hotmix asphalt (HMA) with 5% polymer modifier, reclaimed asphalt pavement (RAP) 20% by weight, and an aggregate blend meeting ASTMD6982.
3. Scope of Verification
- Material conformity (aggregate gradation, binder content, RAP utilisation).
- Compaction quality field density and airvoids.
- Thickness verification core sampling and electronic profilometry.
- Surface roughness International Roughness Index (IRI) measurement.
- Structural integrity Falling Weight Deflectometer (FWD) testing.
- Environmental compliance runoff control and temperature monitoring.
4. Methodology
4.1 Sampling and Laboratory Testing
All samples were collected in accordance with ASTMD3203 (core extraction) and ASTMD2216 (binder content). Laboratory testing was performed at the certified State Materials Laboratory. Key test methods included:
- ASTMD2950 Sieve analysis of aggregates.
- ASTMD2172 Marshall stability and flow.
- ASTMD oven Binder content determination.
- ASTMD7034 Bulk specific gravity.
4.2 Field Measurements
Compaction was monitored using nuclear density gauges (ASTMD6938) and nuclear moisture meters (ASTMD778). Thickness checks employed both manual coring and a portable groundpenetrating radar (GPR) system calibrated to 5mm. IRI values were recorded with a ClassI laser profilometer following AASHTOT 324.
4.3 NonDestructive Testing
The FWD was calibrated per AASHTOT 307. Three load plates (0.5kN, 1kN, 2kN) were applied at 1m intervals across each test lane. Deflection data were processed to derive the modulus of elasticity for each pavement layer.
5. Results and Discussion
5.1 Material Conformity
| Parameter | Specification | Test Result | Compliance |
|---|---|---|---|
| Aggregate 200mm sieve % passing | 40% | 38% | Yes |
| Binder content (by weight) | 5.0%0.5% | 5.2% | Yes |
| RAP proportion | 20%2% | 19.5% | Yes |
5.2 Compaction
The average field density measured at 96% of maximum theoretical density (MTD) with airvoids of 4.5% (spec limit 5%). All values exceed the 93% MTD requirement.
5.3 Thickness Verification
Core logs from 30 locations indicated an average surface course thickness of 100.3mm (2.1mm) and base thickness of 119.8mm (3.3mm). These values are within the tolerance of 5mm prescribed in the contract.
5.4 Surface Roughness
The IRI measured 0.85m/km (average) across the 5.5km test stretch. This meets the project requirement of 1.0m/km and satisfies the AASHTOGuide for smooth ride quality.
5.5 Structural Performance (FWD)
Deflection basin analysis produced the following moduli (average):
- Surface course: 2,800MPa
- Base course: 1,850MPa
- Subbase: 840MPa
All layer moduli exceed the minimum design values (surface 2,500MPa, base 1,600MPa, subbase 700MPa).
5.6 Environmental Compliance
Runoff collection units operated within the permitted discharge limits. Temperature sensors indicated that the mix temperature remained above 150C during placement, satisfying the recommended range for workability and compaction.
6. Conclusions
The verification activities confirm that the constructed asphalt roadway conforms to the design specifications, applicable ASTM and AASHTO standards, and the performance criteria established in the contract. No significant deficiencies were identified. The pavement system is expected to provide a service life of at least 20years under the projected traffic loads.
Recommendations:
- Maintain routine preventive maintenance (crack sealing and surface cleaning) every 23years.
- Conduct periodic IRI monitoring to detect any premature roughness development.
- Retain core and FWD data for future asset management and lifecycle analysis.
Prepared by: Quality Assurance Team XYZ Consulting Engineers
Date: 2June2026
