CN1970892A

CN1970892A - Prefabricated reinforced concrete under-reamed pile

Info

Publication number: CN1970892A
Application number: CN 200610155162
Authority: CN
Inventors: 叶长生
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-12-08
Filing date: 2006-12-08
Publication date: 2007-05-30

Abstract

The invention relates to a prefabricated pile with various basis capacities in construction engineering, especially a prefabricated reinforced-concrete expanding bottom pile, comprising prefabricated reinforced concrete pile and prefabricated enlarging pile head. The side length of upper end surface of enlarging pile head is larger than the diameter of pile segment of prefabricated reinforced concrete pile and the enlarging pile head is welded on the pile segment. The purpose is that the prefabricated reinforced-concrete expanding bottom pile is designed, whose section can thicken and enlarge in construction so as to improve the bearing load of prefabricated reinforced-concrete pile. Compared with prior technology, the invention is provided with more than 30-40% of vertical load improved, more than 30-40% of cost saved, no influence to surrounding buildings when soil is extruded in construction, and so on.

Description

Prefabricated reinforced concrete under-reamed pile

Technical field

The present invention relates to the preformed pile of various foundation bearing capacities such as construction work, particularly a kind of prefabricated reinforced concrete under-reamed pile.

Background technology

At present, be used for the preformed pile of various foundation bearing capacities such as construction work, its structure adopts reinforced concrete prefabricated, and profile is multiple, and the cross section is that solid squares and square hollow or garden type are hollow.During construction, be pressed into or adopt the hammering mode that pile cutoff is squeezed in the ground by joint by joint preformed pile, have certain bearing load power with static pile press.As improving preformed pile bearing load power, gesture increases cost of manufacture than wanting overstriking stake footpath, simultaneously, and also essential tonnage and the freight that improves the construction pile press, also corresponding increase construction cost.

Summary of the invention

The objective of the invention is to design and a kind ofly the time can make the pile body cross section increase thick increase, improve the prefabricated reinforced concrete under-reamed pile of precast reinforced concrete piles bearing capacity in construction.

In order to achieve the above object, the present invention adopts following technical solution: a kind of prefabricated reinforced concrete under-reamed pile, comprise precast reinforced concrete piles, it is characterized in that it also contains prefabricated expansion pile crown, enlarge the pile cutoff diameter of the upper surface length of side of pile crown, enlarge pile crown and be weldingly fixed on the pile cutoff greater than precast reinforced concrete piles.

During the construction piling; owing to precast reinforced concrete piles bottom pile crown is enlarged by enlarging pile crown; make and form the side space between the stake and the soil body; irritate with sand grains or artificial stones then and fill out the side space; the limit is filled out under the sinking limit; the pile body cross section is increased slightly increase to and enlarge the pile crown equal diameter, the bearing capacity of precast reinforced concrete piles is improved greatly.

Description of drawings

The present invention is described in detail below in conjunction with drawings and Examples.

Fig. 1 is present embodiment one prefabricated reinforced concrete under-reamed pile (cross section is a square hollow) structural representation.

Fig. 2 is the structural representation of present embodiment two prefabricated reinforced concrete under-reamed piles (cross section is that garden shape is hollow).

Fig. 3 enlarges pile crown and pile cutoff syndeton enlarged diagram among Fig. 1.

Fig. 4 enlarges pile crown and pile cutoff syndeton enlarged diagram among Fig. 2.

Fig. 5 is that Fig. 3 is along the A-A sectional view.

Fig. 6 is that Fig. 3 is along the B-B sectional view.

Fig. 7 is that Fig. 4 is along the C-C sectional view.

Fig. 8 is that Fig. 4 is along the D-D sectional view.

The specific embodiment

By Fig. 1, shown in Figure 2, present embodiment one, two comprises precast reinforced concrete piles 1, enlarges pile crown 2, enlarge pile crown 2 and adopt the high grade steel concrete to prepare that high fibrous material is prefabricated to form, enlarge the big 3-50 of pile cutoff diameter centimetre of the every side ratio precast reinforced concrete piles 1 in pile crown 2 upper surfaces.As Fig. 3, Fig. 5 and Fig. 4, shown in Figure 7, enlarge pile crown surface layer pre-embedded steel slab 3, precast reinforced concrete piles begins when prefabricated, and the bottom is pre-embedded steel slab 4 also.Enlarging pile crown has two kinds of form of structure, and bearing capacity of single pile is not high, adopts the top cone shape (as Fig. 4, Fig. 7, shown in Figure 8) of point down; And bearing capacity of single pile is higher, adopts hollow cone shape (as Fig. 4, Fig. 5, shown in Figure 6) in the square top and round bottom.

In addition,, improve the pile crown penetration capacity, enlarging pre-buried angle bar 5 on the stake point of pile crown 2 in order to protect the expansion pile crown.

During site operation, will enlarge on the pile cutoff that pile crown is weldingly fixed on precast reinforced concrete piles, and make the pile crown firm welding reliable by pre-buried steel plate 3,4.Be pressed into or adopt the hammering mode that pile cutoff is squeezed in the ground by joint by joint preformed pile with static pile press then; the side space that forms between the stake and the soil body is irritated with sand grains or artificial stones 7 and is filled out; the limit is filled out under the sinking limit, the pile body cross section is increased slightly increase to and enlarges pile crown equal diameter (as shown in Figure 1 and Figure 2).

In sum, the present invention compared with prior art has the following advantages:

1, after the stake end enlarges, makes and form the side space between the stake and the soil body, irritate with sand grains or artificial stones then and fill out the side space; the limit is filled out under the sinking limit; the pile body cross section is increased slightly increase to and enlarge the pile crown equal diameter, vertical bearing capacity increases greatly, can improve more than the 30-40%.

2, the corresponding chap of stake diameter becomes big, and the side frictional resistance increases bearing capacity to stake to be had again and increase.

3, the piling or the formula stake of squeezing into make underground interstitial water discharge ground by the seepage of sand grains packing course by very fast side all around in stake, can not make soil body extruding influence surrounding building.

4, stake end and pile body side can use high pressure to inject chemical cement grout, make to reach the cement consolidation in the sand grains packing course, improve intensity, increase the super supporting capacity of stake.

5, minimum economizing on the use of funds more than the 30-40% on the economic benefit, and very reliable on the workmanship.

Claims

1, a kind of prefabricated reinforced concrete under-reamed pile, comprise precast reinforced concrete piles (1), it is characterized in that it also contains prefabricated expansion pile crown (2), enlarge the pile cutoff diameter of the upper surface length of side of pile crown, enlarge pile crown and be weldingly fixed on the pile cutoff greater than precast reinforced concrete piles.

2, prefabricated reinforced concrete under-reamed pile according to claim 1 is characterized in that the big 3-50 of pile cutoff diameter centimetre of the prefabricated every side ratio precast reinforced concrete piles in expansion pile crown (2) upper surface.

3, prefabricated reinforced concrete under-reamed pile according to claim 2 is characterized in that enlarging pile crown (2) surface layer pre-embedded steel slab (3), and precast reinforced concrete piles (1) bottom is pre-embedded steel slab (4) also.

4, prefabricated reinforced concrete under-reamed pile according to claim 3 is characterized in that enlarging pile crown (2) and is the sharp down cone shape in top.

5, prefabricated reinforced concrete under-reamed pile according to claim 3 is characterized in that enlarging pile crown (2) and is hollow cone shape in the square top and round bottom.

6,, it is characterized in that enlarging pile crown and adopt high grade steel concrete to prepare that high fibrous material is prefabricated to form according to claim 4 or 5 described prefabricated reinforced concrete under-reamed piles.

7, prefabricated reinforced concrete under-reamed pile according to claim 6 is characterized in that going up pre-buried angle bar (5) at the stake point that enlarges pile crown (2).