Permits & Development - Encroachment(EP)/Driveway(DW) Permits - 2007_EP-07-301 thru EP-07-400_ - EP-07-352

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• The Engineer, at the Engineer's discretion,will inspect and test the facilities, materials and methods for producing the concrete to ensure that minor concrete of the quality suitable for use in the work is obtained. 90-10.02 MATERIALS • Minor concrete shall conform to the following requirements: 90-10.02A CEMENTITIOUS MATERIAL • Cementitious material shall conform to the provisions in Section 90-1.01,"Description." 90-10.02B AGGREGATE • Aggregate shall be clean and free from deleterious coatings,clay balls,roots,and other extraneous materials. • Use of crushed concrete or reclaimed aggregate is acceptable only if the aggregate satisfies all aggregate requirements. • The Contractor shall submit to the Engineer for approval, a grading of the combined aggregate proposed for use in the minor concrete. After acceptance of the grading, aggregate furnished for minor concrete shall conform to that grading, unless a change is authorized in writing by the Engineer. • The Engineer may require the Contractor to furnish periodic test reports of the aggregate grading fumished. The maximum size of aggregate used shall be at the option of the Contractor,but in no case shall the maximum size be larger than 37.5 mm or smaller than 19 mm. • The Engineer may waive, in writing, the gradation requirements in this Section 90-10.0213, if, in the Engineer's opinion,the furnishing of the gradation is not necessary for the type or amount of concrete work to be constructed. 90-10.02C WATER • Water used for washing,mixing, and curing shall be free from oil, salts,and other impurities that would discolor or etch the surface or have an adverse affect on the quality of the concrete. 90-10.02D ADMIXTURES • The use of admixtures shall conform to the provisions in Section 90-4, "Admixtures." 90-10.03 PRODUCTION • Cementitious material, water, aggregate, and admixtures shall be stored, proportioned, mixed, transported, and discharged in conformance with recognized standards of good practice that will result in concrete that is thoroughly and uniformly mixed, that is suitable for the use intended, and that conforms to requirements specified herein. Recognized standards of good practice are: outlined in various industry publications such as are issued by American Concrete Institute, AASHTO,or the Department. • The cementitious material content of minor concrete shall conform to the provisions in Section 90-1.01, "Description." • The amount of water used shall result in a consistency of concrete conforming to the provisions in Section 90-6.06, "Amount of Water and Penetration." Additional mixing water shall not be incorporated into the concrete during hauling or after arrival at the delivery point,unless authorized by the Engineer. • Discharge of ready-mixed concrete from the transporting vehicle shall be made while the concrete is still plastic and before stiffening occurs. An elapsed time of 1.5 hours (one hour in nonagitating hauling equipment), or more than 250 revolutions of the drum or blades, after the introduction of the cementitious material to the aggregates, or a temperature of concrete of more than 32°C will be considered conditions contributing to the quick stiffening of concrete. The Contractor shall take whatever action is necessary to eliminate quick stiffening,except that the addition of water will not be permitted. • The required mixing time in stationary mixers shall be not less than 50 seconds or more than 5 minutes. • The minimum required revolutions at mixing speed for transit-mixed concrete shall be not less than that recommended by the mixer manufacturer, and shall be increased, if necessary, to produce thoroughly and uniformly mixed concrete. • When a high range water-reducing admixture is added to the concrete at the job site,the total number of revolutions shall not exceed 300. • Each load of ready-mixed concrete shall be accompanied by a weighmaster certificate that shall be delivered to the Engineer at the discharge location of the concrete, unless otherwise directed by the Engineer. The weighmaster certificate shall be clearly marked with the date and time of day when the load left the batching plant and, if hauled in truck mixers or agitators,the time the mixing cycle started. Contract No. 10-OM7104 91