Non Destructive Testing of Grout 1

[gosai]

Is some one know any NDT method to test Grout strength for masonry? I am looking to find some economical option to test. The grout was never tested at the time of construction

Thanks to all

 

[concretemasonry]

You will not find a very good correlation between non-destructive testing of grout in place with the normally specified grout tests of the grout itself because of the variability and other factors.

Normally, grout on site is testing according to ASTM standards, which is a method of casting s sample in an absorptive form (hopefully the same masonry materials in the wall to produce a sample for testing with the sample ratio of dimension to be compared with the standards and the basis for the specifications. The sample is not placed the in the same manner as actual construction. The best and easiest reliable test is to measure the slump to make sure it is between 8" and 11" and verify the proportions. Too little water is the enemy of proper grouting, especially since grout is usually vibrated to ensure complete filling and placed in lifts for higher walls to allow for absorption of moisture and consolidation.

Usually, grout strength are not critical, but some good engineers to specify a maximum strength to ensure the structure performs as expected. It provides a bond between the reinforcement and the masonry units for the purpose of developing the desired flexural strength of the wall section, but not to over-shoot (one place where a belt and suspenders is not better).

Dick

Engineer and international traveler interested in construction techniques, problems and proper design.