Thaw depth thaw line than clays. Yet another factors are the vegetation and the percentage of the soil organic matter, which influence the bulk density of the soil, and hence thermal conductivity. Thaw depth In soil science, the thaw depth or thaw line is the instantaneous level down to which the soil has warmed to zero degrees celcius. The active layer thickness is the maximum thaw depth over a period of two years. The layer of soil over the thaw depth is called the active layer, while the soil below is called permafrost. The term frost front refers to the varying position
Building material mortar or clay slip. Sand is used with cement, and sometimes lime, to make mortar for masonry work and plaster. Sand is also used as a part of the concrete mix. An important low-cost building material in countries with high sand content soils is the Sandcrete block, which is weaker but cheaper than fired clay bricks. Rock structures have existed for as long as history can recall. It is the longest lasting building material available, and is usually readily available. There are many types of rock throughout the world, all with differing attributes that make them better or worse for