RU2616631C1 - Method of the excavation pit walls shoring by the leader backfill layer - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: method of the walls excavation shoring, in which prior to the soil excavation in the pit the leader setup in the level of the pit bottom of the backfill or buried membrane is carried out, which is becoming the rigid spacer, provides the minimum depth of the pit wall fixing.

EFFECT: increase of the reliability and durability of the whole facility in accordance with regulatory requirements, reduction in consumption of materials and labour intensity of underground part structure construction by reducing the depth of the excavation shoring walls bottom embedding.

3 dwg

Description

The invention relates to construction technology used in the construction of artificial structures.

The present invention is used when arranging pits in the soil for the construction of the underground or underwater parts of buildings and structures.

Known and practically applied in the construction of artificial structures are methods of fixing the walls of pits using spacers and anchors (STO 136-2009, SNiP 2.06.07-87). At the same time, spacers and anchors ensuring the stability and strength of the tongue and groove walls are arranged at the end of excavation in the pit. The grouting cushion (antifiltration layer) arranged at the bottom of the pit after its development, after gaining design strength, also acts as a spacer for fixing the walls of the pit.

The disadvantage of this method is that until the installation of the grouting layer, the stability and strength of the walls of the pit are provided by spacers of the upper tiers and the sealing of the bottom of the sheet pile wall into the ground, which, in accordance with the calculation rules, requires an additional depth of sealing of the bottom of the sheet pile fence below the cement layer. After installing the grouting layer, the stability and strength of the tongue and groove wall is already ensured only due to the rigidity of the spacers and grouting layer. Thus, on each separate construction of the foundation pit enclosure with the grouting (anti-filtration) layer, an additional amount of metal or reinforced concrete dowel for attaching the walls of the pits is spent, which after the grouting is no longer involved in the work. Moreover, the additional laying depth of the tongue-and-groove wall of the pit fastening is up to 50% of the total wall laying depth.

In addition, when developing soil in the pit to the bottom of the grouting layer, excavation is carried out under water, since pumping water out of the pit without grouting is impossible. Given the large volume of work in the pits, the additional costs of increasing the depth of embedment of the walls of the foundation pits and underwater excavation make up significant losses in material and economic resources.

The purpose of the invention is the provision of the possibility of using a shorter sheet pile and the development of soil in a pit dry when arranging pits.

To achieve the objective of the invention, it is proposed that after the tongue is immersed in the ground, first of all, the installation of a grouting (anti-filtration) layer is carried out in any known manner that does not require preliminary soil development (cementation, soil replacement, etc.), and further excavation work is carried out in the traditional way .

The economic effect of this invention is to reduce the cost of manufacturing, delivery, immersion and extraction of sheet piles, as well as the cost of underwater excavation in the construction of the underground part of artificial structures using open pits.

In FIG. 1 shows the design patterns of loads on the tongue wall from the lateral pressure of the soil during the construction of the pit before and after the installation of the grouting layer according to the existing technology.

In FIG. 2 shows the design diagram of the loads on the tongue wall from the lateral pressure of the soil during the construction of the pit according to the inventive method of the leader device of the grouting layer.

In FIG. 3 shows the sequence of work during the construction of the pit according to the method of the leader of the grouting layer claimed in the present invention.

According to the claimed technology, it is proposed that, at the first stage, after the tongue 1 of the foundation pit is immersed, the device of the cement layer 2 at the level of the bottom of the pit using cementation of the soil or other known technologies that do not require preliminary soil development. At the next stage, after the strength of the grouting layer 2 is set, excavation of the pit soil is carried out with simultaneous drainage and installation of the tiers of fastening of the 3 walls of the pit. Further construction work in the pit is carried out according to traditional technology.

The present invention is a method of fastening the walls of the foundation pit enclosure with the leader hardening layer, eliminates underwater excavation, significantly reduces the cost of manufacturing, delivery, sinking and removing sheet piles, as well as accelerates the pace of construction work, ensures high-quality work and, thus, ensures reliability and durability of the entire structure in accordance with regulatory requirements.

Claims (1)

The method of attaching the walls of the foundation pit enclosure, characterized in that prior to the development of the soil in the pit, a leader device is made at the bottom of the pit of the grouting or antifiltration layer, which, becoming a rigid spacer, provides a minimum depth of the pit mounting walls.

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