What are the working ranges: what to take into account

Working ranges required for the construction period are arranged as follows: in the eternal permafrost, a pit of 1.4 hmm m is erupted to a depth of at least 1.5 m from the upper surface of it; A reinforced concrete column (509) with a cross section of 0.3 x 0.3 m at the top of the same height is installed in the dug pits that the upper part of it is issued above the Earth’s surface of at least 1.3 m> or a wooden riser is placed on a lies 1.35 m long and with a diameter of 0.30-0.40 m; The referent pillars (reinforced concrete or wooden) are wrapped freely without nailing with nails in two layers of birch bark or crowd and sprinkled with dry large sand or peat or moss to the full height of the pit, and a sandy or peat sprinkling on top is covered with a clay layer of 0.40 m thick with a slope with a slope for water drainage.

According to drilling, geological sections of the built -up site are compiled, and soil samples and their tests are stored in construction as an excuse for the correctness of the decisions made regarding the foundations.

To determine the characteristics of soil strata, as well as to take samples for the study of the physical and mechanical properties of the soils, rurging is carried out, and the depth of the pits is usually made (by 1 – 2 m) below maximum thawing. RURFING is preferably carried out during freezing. In the pits, the upper boundary of eternal permafrost, the power of individual soil layers, the location of the aquifers and ice layers, and every 0.50 m, the soil temperature with rush thermometers are measured. More reliable data on soil temperature are obtained only after long -term inpatient observations by soil thermometers.

In the pits, every 0.50 m depth and in characteristic layers, soil samples are taken to study the mechanical composition, humidity, water retirement, the angle of natural sloping in talo state, volumetric and specific gravity. The permitted pressure on the forever frozen and thawed soils of the base is determined by the trial load. Such is produced at ambient temperature between zero to -1 °. If the structure is supposed to be built with the calculation of the disappearance of eternal permafrost during subsequent operation, then the trial load on the perzed soil is carried out when it is completely thawed by artificially increasing the temperature of perzed soil to the talus state.