Experience in handling sandy loams under severe winter conditions

Conclusions

• 1. Experience has shown that it is perfectly possible to produce an effective bank of thawed sandy loams during the winter at ambient air temperatures in the range from −40 to −47°C, but the density is 1.6 tons/m³ as against the planned value of 1.8 tons/m³.

• 2. During the experimental work it was found that at temperatures in the range from −17 to −47°C the thawed sandy loams taken from the quarry remained above zero for 2.5–3.5 h; this enabled the soil to be transported over a distance of 5 km to the site and then leveled and rolled while still thawed. It was established that the coneshaped heaps dumped on the plan area must be leveled immediately before rolling. Soil which is leveled as it is spread cools faster and is poorly compacted.

• 3. To keep the soil above zero for a considerable time, it must be transported in large dump trucks with heated bodies.

• 4. Thawed material laid on the frozen layer and compacted in the thawed state joins well at the contacts and has no nonconsolidated intermediate layers or visible boundaries between the layers. Nonconsolidated intermediate layers were formed only when, as a result of deviation from the planned procedure, the soil dumped on the plan area became frozen before rolling and was therefore poorly compacted.

If dumping is performed at an appropriate rate and the correct procedure is strictly observed, a somewhat higher and more uniform density of the material laid in a bank during the winter can be obtained.