1040 -9 MORTAR Proportion mortar used in all brick and block masonry by volume as shown below. Do not add any more water than is necessary to make a workable mixture. Mix No. 1: 1 part Portland cement 1/4 part hydrated lime 3 3/4 parts mortar sand (maximum)
Mix No. 2: 1 part Portland cement 1 part masonry cement 6 parts mortar sand (maximum) Apply Articles 1040- 5, 1040- 6, 1040- 7 and 1040- 8 to all cement, hydrated lime, mortar sand and water. For the hydrated lime and cement portion of Mix No. 1, the Contractor may substitute Type M or TypeS masonry cement that meets ASTM C270 for TypeS masonry cement the minimum compressive strength of the test specimens shall be 2,500 psi at 28 days and the test specimens shall be composed of one part TypeS masonry cement and 3 parts sand. Furnish a Type 3 certification for the Type M or TypeS masonry cement in accordance with Article 106-3. 1040 -10 ADMIXTURES Use admixtures that are on the NCDOT APL . RIP RAP MATERIALS Use field stone or rough unhewn quarry stone for plain rip rap. Use stone that is sound, tough, dense, resistant to the action of air and water and suitable in all other respects for the purpose intended. Where broken concrete from demolished structures or pavement is available, it may be used in place of stone provided that such use meets with the approval of the Engineer. However, the use of broken concrete that contains reinforcing steel will not be permitted. All stone shall meet the approval of the Engineer. While no specific gradation is required, there shall be equal distribution of the various sizes of the stone within the required size range. The size of an individual stone particle will be determined by measuring its long dimension. Stone or broken concrete for rip rap shall meet Table 1042 -1 for the class and size distribution. TABLE 1042 -1 ACCEPTANCE CRITERIA FOR RIP RAP AND STONE FOR EROSION CONTROL Class Required Stone Sizes, inches Minimum Midrange Maximum A 2 4 B 5 8 1 5 10 2 9 14 No more than 5.0% of the material furnished can be less than the minimum size specified nor no more than 10.0% of the material can exceed the maximum size specified.