What type of test can help determine the presence of soluble salts in masonry?

The electrical conductivity test is the most effective method for determining the presence of soluble salts in masonry. This test works on the principle that the presence of salts in a solution increases its electrical conductivity. When an electrical current is passed through a sample of masonry, if there are soluble salts present, they will enhance the conductivity of the material. This measurable increase in conductivity indicates the extent of soluble salts, providing valuable information for assessing potential issues such as efflorescence, which can negatively impact the durability and appearance of masonry structures.

Other tests, such as compression tests, evaluate the strength of the material rather than its chemical composition. Moisture content tests measure water levels within the masonry, but they do not specifically indicate the presence of soluble salts. Similarly, while pH tests can provide information about the acidity or alkalinity of a substrate, they do not directly measure the concentration of soluble salts. Thus, the electrical conductivity test stands out as the most suitable choice for assessing soluble salt content in masonry.