Comparison of Rock Durability Tests

Abstract

The outdoor exposure test and accelerated deterioration tests, such as the freezing and thawing test and sodium sulfate soundness test on dolerite have been conducted to study the deterioration characteristics and durability of material rocks for use as riprap of rock fill dams in each test condition. From a series of tests, the following results have been obtained.
1) The deterioration types of rocks in the freezing and thawing test are basically identical with those in the outdoor exposure test. In these tests, the deterioration types of rocks can roughly be categorized into five groups, N (horizontal), N′ (almost horizontal), A (stepped), B (smoothly curved) and C (intermediate between A and B) based on weight loss curve characteristics.
2) The change types in physical parameters, such as absorption, dry density and dynamic modulus of elasticity with time in the outdoor exposure test are identical with those in the freezing and thawing test. Relationship between change types in physical parameters and rock properties are also identical in these two tests.
3) Even though in the case that any relationship between initial physical parameters and deterioration types can't be recognized at all in the outdoor exposure test, close relationship can be recognized in the freezing and thawing test and the sodium sulfate soundness test.
4) In the case where close relationship between initial physical parameters and deterioration types can be recognized in the outdoor exposure test, criteria values for durability evaluation are all nearly equal in the outdoor exposure test, freezing and thawing test and sodium sulfate soundness test. Therefore, in this case, durability of rocks under natural environments can accurately be evaluated by accelarated deterioration tests.
5) In the case where any relationship between initial physical parameters and deterioration types can't be recognized at all in the outdoor exposure test, criteria values for durability evaluation in the freezing and thawing test are different from those in the sodium sulfate soundness test. Namely, deterioration characteristics of such material rocks can't be considered to have close relationships among these accelerated deterioration tests.