surface layer of rock that is most exposed to, is called "ground".Its properties are directly dependent on various external influences that can cause chemical and physical weathering, air destruction, water erosion, as well as temperature variations.The uppermost part of the soil that is prone to all sorts of additional effects of biological agents is called soil.Influence of soil during the construction of buildings and roads is very high.Depending on the type and properties of stability and strength differs ground cover, the technology and design of the construction work.
by the degree of destruction of land cover and rocks, distinguish the following main groups of soils:
1. Neskalnye.
2. Rock.
first group, in turn, is divided into several groups according to the degree of fragmentation: coarse, clay and sand soils.
coarse soils group includes a mixture of unbound particles larger than 2 mm in size with their percentage of more than 50% by weight.Sandy soils are a mixture of dry bulk particles, the total mass does not have sufficient ductility.
group Clay soils are ground cover, do not let the water, which can be dry or lumpy monolithic state but plastic in a wetted condition.The content of clay rocks must be at least 3% of the total weight.
Rock group soils are divided into metamorphic, igneous and sedimentary.They have a sufficiently tight bond between the mixture and a mineral grain particles, which may occur in a cracked layer or continuous array.
components Igneous rocks are of volcanic origin and its particular classification: effusive, such as basalt and diabase, and in-depth, such as syenite and granite.
The metamorphic rocks are, who were exposed to high temperature and pressure, for example, marble, quartzite and gneiss.Such materials have an increased level of safety.
formation of sedimentary soils group was due to deposits of particles from the slurry opening, which subsequently is converted into a monolithic layer.They are either the result of chemical vapor deposition, or various organic processes.Similarly, there are marl, dolomite, gypsum, limestone and peat.
Terms sedimentation caused further classification on aeolian, water-glacial moraine, sea and river.
clastic rocks comprise two subgroups, which are separated by the nature of the interaction between the particles in the connected (clay) and disconnected (sand and gravel).
properties of each group of soils depend on the appearance of the rocks, but they can vary greatly in chemical and mineralogical composition, the nature of the communication, the shape and size of the particles.
thus ground is dispersed multiphase system, in its natural state it has three phases: the mineral constituents of rocks, water and air.
