SU1325135A1 - Method of setting a helical pile into soil - Google Patents

Abstract

The invention relates to the field of construction and can be used in foundation drilling when installing helical piles in the ground. The purpose of the invention is to increase the bearing capacity of the pile on the foundation soil. To do this, before fixing each intermediate blade 4 on the shaft 1, the pile is upset before obtaining the design ground resistance of the blade base. The immersion of each of the intermediate blades 4 is carried out to a depth exceeding the design depth by the amount of displacement of the corresponding blade along the trunk during upsetting. After immersing the upper blade 5, it is unscrewed in steps. 2 Il. you sl 00 to SP OO cl

Description

The invention relates to construction, in particular, to foundation construction, and can be used when installing screw piles of increased bearing capacity in the ground to fix structures to the ground, such as pipeline supports, bridges, lines, power transmissions and communications, non-aerodynamic structures, etc. as well as piles with a higher area of bearing in industrial and civil engineering during the construction of blast furnaces, high-rise structures, one-story large-span nrom-buildings, elevators, moorings and other structures.

The purpose of the invention is to increase the height of the pile’s ability to pile on the foundation soil.

FIG. 1 depicts a pile screw installed in the ground in the process of unscrewing the upper blade when working on the depressions of the load, a general view; in fig. 2 - the same, in the working position when working on pulling or alternating 1e load.

The screw that is installed in the ground contains sgvol 1 with tip 2 in the lower part iiei i. On the barrel 1 are mounted with the possibility of moving the bottom 3, intermediate 4 and top 5 screw blades of the same internal diameter, slightly larger than the external diameter of the trunk 1. Lower 3 and intermediate 4 piles of the pile for pressing into the pressing loads are pushed by elastic plates 6, interacting with ring lugs 7 fixed on the barrel 1 (Fig. 1). Instead of ring lugs 7, it is possible to manufacture in the body of the trunk 1 single-slotted grooves (not indicated). During operation of the pile for pulling loads, fixation of the lower blade, 3 is carried out by means of ribs 8, and intermediate 4 blades by means of bushings 9, located between blades 3 and 4 (Fig. 2). In order for the pile to work on alternating loads, in addition to the ribs 8 and the sleeves 9, it is sufficient to provide the upper intermediate blade 4 with plates 6. And the barrel 1 with a stop 7 (Fig. 2). The blades 3 and 4 are positioned at distances that ensure their complete inclusion in the work, taking into account the compaction of the i-root, at the position of the osazhivanpi.

The method of installation in the ground of the screw pile is as follows.

In the ground at the design mark, the barrel 1 is immersed by driving, indentation, vibration or installation in a pre-drilled well (Fig. 1 and 2). To reduce frontal deactivation by eliminating the soil compaction zones, the ribs 8 can be attached at an angle of 5-15 ° to the cone of tip 2, due to which the barrel 1 is rotated during immersion (Fig. 2). After installing the barrel, 1 is immersed at the design mark by screwing with HOMOHIH

inventory rod lower blade 3 until its plates 6 pass through the lower ring stop 7, while plates 6 are straightening, abut against stop 7, fixing the blade 3 (Fig. 1). It is possible to simultaneously immerse the screwing in of the barrel 1 together with the lower blade 3, in which case the latter is rigidly attached to the barrel 1 before immersion (not shown). Subsequently, they are successively submerged to the design depth and settle each of the intermediate blades 4 to obtain the design ground resistance of the ground. The planting is performed using an inventory rod, by means of which the screwing up is carried out by driving, pressing or vibrating it. The initial depth of immersion of each of the intermediate blades 4 is taken higher than the design one by the amount of mixing of this blade 4 along the barrel and 1 when it is deposited.

The amount of mixing of each of the blades 4 during the deposition of the design ground resistance of the base of the blade 4 (design failure during driving) is determined by pre-installation into the ground by the proposed method of experienced piles which can be reused and the blades can be fixed at any mark. And each

of the intermediate blades of these piles, they are immersed to the design elevation level by the value of hii Ck- -hii-, where k is the serial number of lonasty, starting from the bottom; Ck is the value of the unresponsive fe th area, necessary to eliminate the screw cavity in

the soil cut by the k-blade between k- and k- (blades, hk-- is the magnitude of the immersion depth of the i-1th blade above its design immersion depth (for the lower blade).

40

G - i. in {D -df)

five

where is hk. - the distance between the k – 1 th blades; V .i - the volume of single-turn plot

blades (); t is the pitch of the helical blade; D-1 - blade diameter; dc is the diameter of the stem (for the lower blade C | 0).

By the moment of obtaining the design resistance of the soil of the base when the blade 4 is set up its plate 6, an annular stop 7 passes and, straightening, fix the position of the blade 4 on the barrel 1 when working on pressing loads (Fig. 1). When the screw pile is working on pulling out or alternating loads, before immersing the intermediate blades 4, they immerse the sleeves 9 until they stop into the previously immersed blade (Fig. 2). Moreover, the sleeve 9 can be immersed by driving, indentation, vibration or screwing.

At the end of the installation process, the piles are immersed by screwing the upper blade 5 to a depth exceeding the installation depth of the upper intermediate blade 4 by 3-4 turns. After that, the upper blade is unscrewed in 5 steps, at first each of which is performed before the ground is completely compacted over the upper intermediate blade 4 (the degree of compaction of the soil should be negotiated in the project). At each stage, the twisting of the blade 5 is carried out by 3-4 turns. As a result of the compaction of the soil around the pile, a notch is formed, which is filled up with layer-by-layer compaction with low-compressible soil, for example, medium or coarse sand, gravel, etc.

Claims (1)

Invention Formula The method of installation in the ground screw pile, including immersion of the barrel with the bottom screw blade of the pile in the ground at the design mark and subsequent immersion of the intermediate blades with their fixation on the trunk and the upper blade, in order to increase the bearing capacity of the pile on the base soil, by fixing each intermediate blade on the barrel, it is deposited to obtain the design resistance of the soil of the base to the blade, while immersion of each of the intermediate blades is carried out to a depth of 5 times greater than ktnuyu depth by the amount of movement along the respective blades during rein-back trunk, and after immersion upper blade carried out in steps of unscrewing it, at the beginning of each of which produce squat blade.