Masonry Magazine April 1999 Page. 14
Table 2
Specifications for Masonry Structures (ACI 530.1-98) Submittal and Inspection Requirements
LEVEL 1 QUALITY ASSURANCE
MINIMUM TESTS AND SUBMITTALS
Certificates for materials used in masonry construction indicating compliance with Contract Documents
MINIMUM INSPECTION
Verify compliance with the approved submittals
LEVEL 2 QUALITY ASSURANCE
MINIMUM TESTS AND SUBMITTALS
Certificates for materials used in masonry construction indicating compliance with Contract Documents
Verification of f'm prior to construction, except where specifically exempted by the Code
MINIMUM INSPECTION
As masonry construction begins, verify the following are in compliance:
Proportions of site prepared mortar
Construction of mortar joints
Location of reinforcement and connectors
Prior to grouting, verify the following are in compliance:
Grout space is clean
Placement of reinforcement and connectors
Proportions of site prepared grout
Construction of mortar joints
Grout placement is in compliance
Observe preparation of grout specimens, mortar specimens, and/or prisms
Verify compliance with the required inspection provisions of the Contract Documents and the approved submittals
LEVEL 3 QUALITY ASSURANCE
MINIMUM TESTS AND SUBMITTALS
Certificates for materials used in masonry construction indicating compliance with Contract Documents
Verification of f'm
prior to construction
every 5,000 sq. ft. (464.5 m2) during construction
Verification of proportions of materials in mortar and grout delivered to the site
MINIMUM INSPECTION
From the beginning of masonry construction and continuously during construction of masonry, verify the following are in compliance:
Proportions of site mixed mortar and grout
Placing of masonry units and construction of mortar joints
Placement of reinforcement and connectors
Grout space prior to grouting
Placement of grout
Observe preparation of grout specimens, mortar specimens and prisms
Verify compliance with the required inspection provisions of the Contract Documents and the approved submittals
The Code provides minimum quality assurance levels, and the designer may elect to provide higher thresholds of quality assurance in the project specifications.
Hot Weather Construction
Previously, Hot Weather Code requirements of limiting the spreading of mortar beds greater than 4 feet ahead of masonry and placing units within one minute of spreading mortar were imposed when the ambient air temperature exceeded 100°F or 90°F with a wind velocity greater than 8 mph.
The Hot Weather requirements of ACI 530.1-99 are somewhat more comprehensive. The highest threshold is at an ambient air temperature of 115°F or 105°F with a wind velocity greater than 8 mph. The ambient air temperature is defined as the average of high and low temperature prediction by the local weather bureau for the subsequent 24 hour period.
At this higher threshold, the Code requires shading of materials and mixing equipment from direct sunlight, maintaining sand piles in a damp loose condition and preparing equipment to produce mortar and grout below 120°F in preparation for masonry construction.
During construction, the Code provides for liberal use of cool water in mixing mortar and grout and retempering mortar. Ice water may be used, but the ice is not to come into direct contact with the mortar or grout materials. Equipment and mortar boards should be flushed frequently with cool water.
When ambient air temperature is above 100°F or above 90°F with a wind velocity greater than 8 mph, sand piles are to be maintained in a damp loose condition and equipment is to be cool enough so that mortar temperature is below 120°F.
During construction, cool water should be used in mixing mortar and grout and for retempering mortar. Ice water may be used, but the ice is not to come into direct contact with the mortar or grout materials. Equipment and mortar boards should be flushed frequently with cool water.
After construction, when the ambient air temperature is above 100°F, or above 90°F with a wind velocity of greater than 8 mph, newly constructed masonry should be fog sprayed three times a day for three days.