Concrete Study Notes: Pavement & Strength

• The following are potential study notes based on the text provided.

Test Questions and Answers

• Extruder is not included in moisture content determination.
• The minimum strength requirement for Portland Cement Concrete Pavement is both absorption and mortar strength.
• Index of Retained Strength (IRS) of a bituminous mix is its dry stability of 3,300 lb and wet stability of 2,250 lb, having a moisture content of 1.1%
• 650 psi is the minimum strength when tested by the third-point method.
• Forms used in concrete paving shall remain undisturbed for not less than 12 to 24 hours.
• Sawing of the joint shall commence as soon as the concrete has hardened sufficiently to permit sawing without excessive raveling, usually 4 to 12 hours.
• Class C is the recommended class of concrete for all superstructure.
• Curing is done after concrete pouring to minimize cracking and to ensure proper development of concrete strength.
• It shall be constructed when there is an interruption of more than 30 minutes in the concreting operations: Sawing of joints
• Determining the thickness of a finished pavement: Core sample
• One set consisting of 6 specimens of beam test specimen shall be taken from concrete pavement of 3.30m^2, 230mm depth or for every fraction thereof.
• Purpose of capping concrete cylinders prior to testing of compression: To safeguard the end of the cylinder from premature breaking, resulting to improper application of load.
• A common test to determine the cleanliness of an aggregate: Slump test
• Degree of compaction required for embankment is at least 95%.
• Coarse aggregates used in concrete pavement shall contain not more than 1% of material passing the sieve no. 200 by washing.
• In molding concrete cylinder specimen, each layer should be rodded 25 times and each layer should be rodded 25 times.
• To uphold the verticality of the cylinder is a common test to determine the cleanliness of an aggregate.