Rock samples similar to those used in previous tests were used for freeze-thaw tests. Because of the high porosity and high water absorption of the conglomerate, the samples disintegrated easily when frozen and thawed. The conditions of the samples in different freeze-thaw cycles were recorded, but the weight losses were not recorded. Testing was continued until all the samples had disintegrated. The number of freeze-thaw cycles was recorded, and rough estimates were made of the resistance to freezing and thawing of the weathered rock samples and the samples after consolidation.
Freeze-thaw tests were performed on four groups of samples (three samples in each group) after consolidation using AC, AS, and SS at concentrations of 1:10 (water), and of 10% PS. Samples were first heated at 105-110 °C to constant weight, after which they were soaked in water at 20 °C for four hours. They were then placed in a freezer at -30 °C for four hours. Repeated cycles of freezing and thawing consisted of thawing for four hours (20 °C water) and freezing for four hours (-30 °C), with each eight-hour period being counted as one cycle.
A minute crack developed in one of the 10% PS-consolidated samples in the third freeze-thaw cycle, at which time the other two samples were still intact. In the fifth freeze-thaw cycle, minute cracks also appeared in the other two. In the eleventh freeze-thaw cycle, there was expansion of the cracks in all three. During the seventeenth cycle, the corners of two of the samples fell off. During the twenty-eighth cycle, the two samples with chipped corners broke into two or three pieces. By the forty-fifth freeze-thaw cycle, all three rock samples virtually disintegrated.
One of the samples treated with AS developed a crack in the eighth cycle, at which time the other two samples were essentially intact.
In the twelfth cycle, the crack that had already appeared expanded, a small piece broke off from the lower part of the second sample, and a minute crack also developed in the third rock sample. By the forty-fifth freeze-thaw cycle, there was clear enlargement of the cracks in all three rock samples. However, there was no evidence of disintegration.
The corners of one of the AC samples broke off at the twentieth freeze-thaw cycle. The other two samples were basically intact. In the twenty-sixth cycle, there was disintegration of the lower portion, whereas there were no changes in the other two samples. During the thirty-third cycle, distinct cracks appeared in the sample that had begun to disintegrate, and the corners fell off of the other two samples, which also showed
Abrasion loss of consolidated rock sample in the wind tunnel test (wind only): C = unconsolidated; D = AC; A = AS; S = SS; P = PS.
Figure 10
Abrasion loss of consolidated rock sample in the wind tunnel test (wind plus sand):
Some disintegration. By the forty-third freeze-thaw cycle, all three samples had basically disintegrated.
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