SU1476068A1 - Underground part of structure - Google Patents

Abstract

The invention relates to the erection of an underground part of a structure and reduces the laboriousness of the work on the construction of a structure. The underground part of the structure includes pile foundations consisting of pile 1 and grillage 2, or columnar and strip foundations placed on compacted subsiding soil within the deformable zone, and a basement with enclosing walls 6 in the form of walls or columns with overlaps 8. The basement is made not less than 0.6-1.0 wide in the thickness of the subsiding soil. The depth of the basement filling is determined from the condition D _B = (1.1-1.2) [(PD + P _F + P _F ) - P _SL ] / ρ, where D _B is the basement depth

ρ is the average value of the density of the subsidence soil in a water-saturated state

D is the depth at which the difference ρD + P _F + Pb) - P _SL has the maximum value

P _F - additional pressure from the foundation

PЪ - additional pressure from the basement floor

P _SL is the initial subsidence pressure at the foundation depth. The foundation of the basement at a specified depth eliminates the compaction of the subsiding basement over its entire thickness while ensuring the bearing capacity of the soil base. 2 Il.

Description

d out of condition d 5 (1,1-1,2) (p d + + Pf + Pp P5f J / j, where d is the basement depth, p is the average density of the subsidence soil in a water-saturated state, d is the depth, at which the difference (yd + + РЈ + Р ,,) - Р5е has the maximum value, Pf is the additional pressure from the basement, Pf is the additional pressure from the basement floor, Р sc is the initial subsidence pressure at the foundation depth. It does not exclude the compaction of the subsiding basement over its entire thickness while ensuring the carrying capacity ground base. 2 ill.

The invention relates to the construction and construction of the underground part of buildings and structures on forest subsurface soils.

The purpose of the invention is to reduce the complexity of the construction works.

Fig. 1 shows the underground part of the structure on pile foundations; figure 2 - the same, figure 1 column or strip foundations.

The underground part of the basement structure includes pile foundations consisting of piles 1 and grillage 2, or columnar or strip foundations 3, placed on compacted subsiding soil 4 within the deformable zone 5, enclosing walls 6, internal supporting structures 7 in the form of walls or columns with ceiling 8.

Depending on its purpose, the basement is made of a single or multi-storey under construction along its entire length and a width B of not less than 0.6-1 of the thickness of the travel soil layer Hsj. In case the width of the structure is less than (0.6-t) HSi, the width of the basement is increased by the construction of additional rooms outside the contour of the structure. At the same time, for structures whose shape is close to a circle or square in plan, the width of the basement is В Hs, and for structures in terms of a rectangular shape (with an aspect ratio of 3: 1) В 0.6HS {. The value of the thickness of the subsidence soil N s is determined taking into account the planning of the area by filling or cutting the soil.

The depth of the underground part of the structure is determined according to engineering geological surveys carried out prior to construction, which determine the thickness of the subsidence thickness Hst and the average density of the soil with water saturated within the subsidence thickness. From these data, plots of the distribution of household pressure 9 are plotted from the elevation mark or layout 10, the initial subsidence pressure at the foundation depth P5e 11, the average additional pressure 12, 13 from the base PЈ, and after the PJ foundation. by the method of successive approximation by the difference of values between the total pressure from the respective weight of the soil fd, the additional pressure from the foundation Pr and the floor Po and the initial subsidence pressure PSt, the depth d, n is determined and which this difference has the greatest value. The depth of the basement dg, at which there will be no subsidence of the soil, will be d8 (1.1-1.2) (f J + P) -Psf) / j. The depth of the underground part can also be determined graphically. To do this, in the pressure distribution scheme pd, РЈ, РЈ, within the thickness of Hse, tangent 14 is applied to the change curve over the depth of the initial subsiding pressure 11 so that this tangent goes parallel to the total change curve over the depth of the household pressure 9 of its own ground weight, pressure 12 and 13. According to the intersection points of the tangent 14 with the vertical axis, the cutting depth of the subsiding depth db is determined, at which there will be no subsidence.

Due to the uneven subsidence of the soil from its own weight, errors in determining the physicomechanical characteristics of the soils during laboratory tests obtained in the above-described way, the value of d $ is multiplied by a factor of 1.1 for rectangular and 1.2 for round and square in terms of pits.

After the installation of the basement, to avoid subsidence of the load from the load, pile foundations are erected with the remaining subsurface stitching or the usual columnar or strip foundations on the soils compacted within the deformable zone. At the same time, pile foundations are prescribed from the condition of piling in type 1 subsidence soils without additional loading by negative friction forces. The soil within the deformable zone is compacted with tampers with the installation of ground pads, rammed trenches and other methods.

The basement is made by welding the top layer of the subsurface to a depth of db. The foundation of the basement at this depth and its execution with the specified width eliminates the compaction of the subsiding soil to its full thickness, while ensuring the bearing capacity of the base, which reduces the laboriousness of the construction works.

Claims (1)

Invention Formula The underground part of the structure, including the foundation, made in the form of blocks on pre-compacted subsiding soil or from piles that cut through the subsurface tunnel, and the basement, which in order to reduce the labor intensity and construction works, the basement is made with a width of at least 0 6–1.0 of the thickness of the subsidence soil, and its depth is determined from the condition dB (1,1 -1t2) (frf + PЈ + P {) - Ps, J / f, where d 5 is the basement depth, p is the average density of the subsidence soil, in a water-saturated state j d is the depth, which difference (+ Pf + Pf) - PSI has the maximum value j - additional pressure from the foundation j - additional pressure from the basement floor - initial drawdown pressure at the foundation depth. H p pf si ten