Seepage barriers between the water supply and the frost zone. Soils developed from in-situ weathering of rocks. The graph in figure 24 shows a good overall agreement between LTPP and historical maximum frost depth predictions. Muck implies organic matter. When existing subgrade soils do not meet minimum compaction requirements and are susceptible to large settlements over time, consider the following alternatives: They are easily disturbed under construction activities.
Using frost estimates computed based on in-situ data, frost penetration profiles were analyzed for each of the 41 LTPP sites for all available years of data.
Increase the pavement structural layer thickness to account for strength reduction in the subgrade during the spring-thaw period for frost-susceptible groups F1, F2, and F3. Peat containing a high degree of easily identifiable fibers is often called fibrous peat for geotechnical applications. Furthermore, the depth of the top of the first unbound layer was different for each SMP site, which occasionally limited frost determination at shallow and medium depths where the first unbound layer was placed below the expected freeze depth. Sandy clays of medium plasticity found in the semiarid regions of the southwestern U. Some of the terms are true geological terminology, while some are local or regional terminology. Identification of Frost-Susceptible Conditions The most distinguishing factor for identifying a pavement frost hazard condition is water supply. A surface soil that may be described as a sandy silt of low plasticity or a silty sand that is well suited to tilling.