Common use of Field Sampling Clause in Contracts

Field Sampling. 1. Quality assurance testing and sampling of the slurry seal mixture will be performed by the County of Orange OC Public Works Materials Laboratory, which shall include all the components necessary and required in the laboratory approved mix design. 2. The testing and sampling shall be performed by the County of Orange OC Public Works Materials Laboratory. The Engineer may, at any time during the project, suspend work in order to verify or interpret test results. 3. During the performance of the work, the Contractor shall arrange for taking at least 2 field samples of the mixed slurry per slurry truck, per day, for the purpose of wet track abrasion tests. 4. The slurry seal mixture sample shall be taken from the slurry truck by a qualified technician from the approved material testing laboratory. 5. Test results for the slurry seal mixture used during the course of the job will be based on random samples taken from the slurry seal truck at the time the material is being placed. These test results shall comply to the requirements of the wet track abrasion test, ASTM D3910, this Scope of Work, and the following values: Test Test Method Requirement Minimum Maximum Wet Track Abrasion (weight loss in grams per square foot) ASTM D3910 0 75 Consistency (CMS) ASTM D3910 20 30 Extraction Test (emulsion content, percentage) ASTM D2172 + 1.0 Percent of mix design Water Content (percentage of dry aggregate weight) ASTM D2172 --- 25 6. The slurry mixture sampled shall be of aggregate, asphalt emulsion, water, and additives, and shall be mixed in the slurry truck mixer and spreader or pre-mixed from the plant. It shall reflect the same slurry produced in the approved mix design and shall be prepared to a homogeneous flowing consistency and shall meet the requirements of the consistency test. 7. The slurry seal mixture sample taken from the slurry truck shall be formed into a disk by pouring it in the circular opening of a poly (methyl) methacrylate (PMMA) template resting on a larger circlet of roofing felt. 8. The method for testing shall follow ASTM D3910, as follows: After removal of the template, the disk-shaped specimen is dried to constant weight at 140°F. The cured slurry is placed in a water bath for one hour, then mechanically abraded under water with a rubber hose for 5 minutes. The abraded specimen is washed free of debris, dried at 140°F and weighed. The loss in weight expressed as grams per square foot is reported as the wear value (WTAT loss). 9. For continuous flow mixing, the Contractor shall arrange and schedule an aggregate moisture test taken for each day of the slurry operation. Results of the test shall be submitted to the Engineer for review. 10. For continuous flow mixing, the Contractor shall perform an aggregate gradation test (ASTM 136) for every 250 tons of aggregate used during the job. 11. For continuous flow mixing, the Contractor shall perform at least one sieve analysis test (ASTMD244) for each load of emulsion delivered to the job site. An additional sieve analysis test shall be performed on the first day for each work week that the job is in progress.