RU2284393C1 - Foundation pit construction method - Google Patents

Abstract

FIELD: excavations, bordering of excavations, making embankments, particularly foundation pits.

SUBSTANCE: method involves ramming and compacting ground by means of free-fall rammer moving in guiding hole; laying concrete mix on pit bottom through water-bearing bed height; setting concrete mix; perforating orifice through ready concrete plug by means of free-fall rammer; ramming pit up to design depth.

EFFECT: increased working efficiency, possibility to form pits in water-bearing ground due to elimination of ground water influx into pit bottom and prevention of loosened ground caving inside the pit.

Description

The invention relates to construction, and in particular to methods for constructing foundation pits for foundations by shock-rope method.

A feature of the method is that pits for individual foundations do not come off, but are rammed to the required depth with simultaneous compaction of soils around and under the bottom of the pit. One of the problems when arranging pits for foundations under the shock-rope method is the inability to work in water-saturated soils due to the collapse of the soil softened by water into the cavity of the pit and the suction of the tamper, which restrains its extraction to repeat the cycle of impacts.

The prototype of the claimed invention is a method of excavation, including ramming, falling from a height of 4-8 m in the guide shaft or on the guide rod tamper, having the form of a future foundation [1].

The disadvantage of this method is the low manufacturability, due to the fact that in the process of tamping the pit with the passage of the aquifer, water enters the cavity of the pit, softening the walls, which leads to collapse of the soil into the cavity of the pit. This leads to the high complexity of the work and, as a rule, the impossibility of installing rammed pits in water-saturated soils.

The basis of the invention is the task of preventing the entry of water from the aquifer into the cavity of the rammed pit and the collapse of the soil into the face.

The essence of the invention lies in the fact that in the method of excavating a foundation pit, including tamping with compaction of the soil falling by tamper in the guide shaft, after tamping the trench to the height of the aquifer, concrete mix is laid in the bottom of the pit, after setting the mixture in the tampon, the hole of the falling tamper is punched and continue the process of ramming the pit to the design depth.

As a result, the use of the proposed method for constructing a foundation pit under the foundation allows to significantly increase labor productivity and to provide the possibility of tamping pits in water-saturated soils by preventing the entry of groundwater into the bottom of the pit and collapse of its softened soil inside the pit.

The method is as follows. The pit is rammed by tamper falling in the guide shaft to the aquifer. A concrete mix of a tampon is laid in the bottom of the pit to the entire height of the aquifer. After the concrete has set, the hole is punched through a falling rammer. Then continue tamping the pit to the design depth.

The source of information

1. Guidance on the design and construction of foundations in rammed pits. M .: Stroyizdat, 1985.

Claims (1)

A method of arranging a foundation pit for foundation, including tamping with compaction of the soil by tamper falling in the guide shaft, characterized in that, after tamping the trench to the height of the aquifer, concrete mixture is laid in the bottom of the pit, after setting the mixture in the tampon, a hole is made by the tamping ram and the tamping process is continued to design depth.