520 Pneumatically Placed Mortar

1. Specification:

Item 520.02 C&MS

2. Sampling and/or Inspection Requirements:

The Engineer will approve the preparation and condition of all surfaces immediately before the application of the mortar.

Pre-construction testing of Mortar

Preconstruction testing requires application of pneumatically placed mortar and actual testing of the finished product.  Follow requirements of 520.09

Acceptance of placed mortar

After curing, sound all patched areas. In addition to sounding, acceptance of mortar will be based on 4" cores taken from the patched areas and tested for compressive strength.

The Engineer will determine the location of the cores to be taken. One core shall be taken for every 200 ft2 (20 m2) of pneumatically placed mortar. Visually inspect cores for voids and other defects indicated in Item 520.11

The cores shall be tested by an independent laboratory for compressive strength. The required minimum average for 7 days is 3000 psi (21 MPA) with no single core strength less than 2600 psi (18 MPA).

Defective or unsound patches should be handled in accordance with removal and retesting procedures in Item 520.11.

3. Method of Tests:

ASTM C41, C39