Investigation of the Effect of Larestan’s Pipeline Water on the Mechanical Properties of Concretes Containing Granite Aggregates

Table 4

The degree of water hardness based on the American Society of Agricultural and Biological Engineering (No. S-339) [38].

Degree of hardness	ppm (mg/L)
Soft	<17.0
Slightly hard	17.1–60
Moderately hard	60–120
Hard	120–180
Very hard	>180