CN202012074U

CN202012074U - Expansive concrete bored pile

Info

Publication number: CN202012074U
Application number: CN2011200638851U
Authority: CN
Inventors: 赵顺增; 刘立
Original assignee: China Building Materials Academy CBMA
Current assignee: China Building Materials Academy CBMA
Priority date: 2011-03-11
Filing date: 2011-03-11
Publication date: 2011-10-19
Anticipated expiration: 2021-03-11

Abstract

An expansive concrete bored pile belongs to the technical field of concrete pile foundation work, which comprises a reinforcement cage and a poured pile body. The pile body is in bamboo joint structure and formed by normal concrete segments and expansive concrete segments which are poured alternately, the expansive concrete segments are thicker than the normal concrete segments, and the bottom end of the pile body is also provided with a solidified body formed by pouring cement paste. The height of every segment is not less than 1000mm and equal or not equal, and the top of the pile body is a normal concrete segment. The pile body of the expansive concrete bored pile utilizes alternate pouring of the expansive concrete and the normal concrete, and the expansive concrete segments form expanded joints, thereby remarkably improving the relative resistance of motion between the pile body and soil around the pile body, and increasing mechanical interaction between pile body concrete and combination soil. The solidified body formed at the pile end is capable of increasing pile end resistance and increasing a single pile bearing capacity by 30% to more than one time compared with a normal concrete bored pile.

Description

The expansive concrete castinplace pile

Technical field

The utility model belongs to the concrete pipe base field of engineering technology, relates to a kind of cast-in-place concrete pile of new structure.

Background technology

Cast-in-place concrete pile is a kind of structural measure that improves basic supporting capacity that often uses in worker China Democratic National Construction Association and infrastructure, is extensive use of in the area of highrise building, bridge and some earth bearing strength differences.Adopting technical measures, improve bearing capacity of single pile, is the important research contents in bored concrete pile technology field, and many achievements have been arranged in this respect, props up expansion (dish), end (side) post-grouting technology etc. as expansion pile crown (end is expanded in boring), pile body.These technology can both improve the castinplace pile single pile bearing capacity, not only exist technology comparatively complicated, and reliability is poor, time-consuming problem such as take a lot of work, and formed pile body structure is single, is difficult to effectively improve the castinplace pile bearing capacity of single pile.

The Chinese patent of publication number CN100519951C (inventor: Japanese plum source, together high, Wang Chuanjia) a kind of job practices of dry auger boring pouring pile is disclosed, be to utilize the spiral drilling machine dry hole to projected depth, build ordinary concrete, pile body is laid two grouting behind shaft or drift lining pipes, the commercially available ordinary concrete expansion agent of admixture 5% in the cement grout of grouting behind shaft or drift lining, can form firming body at the stake end after the slip casting, can improve end resistance, appropriateness improves bearing capacity of single pile; But its pile body structure and material itself is not broken through.

The utility model content

The purpose of this utility model provides a kind of expansive concrete castinplace pile of new structure, makes its cost that can significantly reduce the expansive concrete castinplace pile, compares with the ordinary concrete castinplace pile, obviously improves the castinplace pile bearing capacity of single pile.

To achieve these goals, the utility model is by the following technical solutions:

The present invention proposes a kind of expansive concrete castinplace pile, comprises reinforcing cage and builds the pile body that forms, and described pile body is formed bamboo knot shaped structure by ordinary concrete section of alternately building and expansive concrete section, and the expansive concrete section is thick than the ordinary concrete section.

Wherein, the pile body bottom is also with the firming body that is formed by the cement slurry placing.

In the above expansive concrete castinplace pile, the height of described ordinary concrete section and expansive concrete section is not less than 1000mm.The height of described ordinary concrete section and expansive concrete section equates or is unequal.

Every section of described pile body is highly equal or unequal.The top of described pile body is the ordinary concrete section for one section.

Adopt technique scheme, pile body of the present utility model partly adopts expansive concrete and ordinary concrete to build at interval, make position, expansive concrete section place, protruding joint because of concrete expansion formation, similar with ring, can significantly improve pile body and native relative motion resistance of stake week, can increase considerably pile body concrete and the mechanical snap power that combines between the soil, compare with the ordinary concrete castinplace pile, significantly improve bearing capacity of single pile; Compare with full expansive concrete castinplace pile, save expansion agent; Compare with stake rear flank slurry injection technique, technology is simple.On the other hand, the curing physical efficiency that pile-end post-grouting forms improves end resistance, cooperates with the pile body of bamboo knot shaped structure more to significantly improve bearing capacity of single pile.

Description of drawings

Fig. 1 is that the utility model castinplace pile one embodiment (stake of I type) constitutes schematic diagram;

Fig. 2 is that another embodiment of the utility model castinplace pile (stake of II type) constitutes schematic diagram.

The specific embodiment

Embodiment 1:I type stake and manufacturing thereof

Referring to shown in Figure 1, install in the priming concrete pile hole 3 of reinforcing cage at below ground, build ordinary concrete and expansive concrete that the strength grade according to designing requirement configures successively, form ring shape ordinary concrete section 1 and expansive concrete section 2, the height of every section concrete is not less than 1m; At every turn building of ordinary concrete and expansive concrete highly both can be identical, also can be different, and ordinary concrete is preferentially used at the stake top.Wherein, expansive concrete is admixture 15～30wt% expansion agent and forming in ordinary concrete, and expansion agent can be commercially available cement expansive material, as the UEA expansion agent.

After castinplace pile is built and is finished, to test pile length of time.With reference to existing national sector standard " technical code for building pile foundation " JGJ94 bearing capacity of single pile is tested, the result shows: under the identical ground soil property situation, and diameter 800mm, the castinplace pile of long 35m, adopt ordinary concrete, the veritcal limit load of stake is 4200KN; Adopt the stake of I type expansive concrete, the veritcal limit load is 5600KN.Compare with common filling pile, the stake of I type can improve bearing capacity of single pile more than 30%.

Embodiment 2:II type stake and manufacturing thereof

Referring to shown in Figure 2, install in the priming concrete pile hole 3 of reinforcing cage at below ground, build ordinary concrete 1 and expansive concrete 2 that the strength grade according to designing requirement configures successively, form the ring shape pile body that ordinary concrete section 1 and expansive concrete section 2 are interlocked, the height of every section concrete is not less than 1m, at every turn building of ordinary concrete and expansive concrete highly both can be identical, also can different (stakes of I type); After pile body was built 12 hours, with the cement slurry of slush pump by Grouting Pipe 4 pressure injection admixture expansion agent (as the UEA expansion agent) in the weak soil of stake end pre-buried in the pile body, cement solidification forms stake end firming body 5 (forming process of firming body 5 is called placing) after 24 hours.

During pile body was built, expansive concrete was admixture 15～30wt% expansion agent and forming in ordinary concrete, and expansion agent can be commercially available UEA expansion agent.

With reference to existing national sector standard " technical code for building pile foundation " JGJ94 this bearing capacity of single pile is tested, the result shows: under the identical ground soil property situation, and diameter 800mm, the castinplace pile of long 35m, adopt ordinary concrete, the veritcal limit load of stake is 4200KN; Adopt the stake of II type expansive concrete, the veritcal limit load is 9000KN.Compare with the ordinary concrete castinplace pile, this II type stake can improve bearing capacity of single pile more than 1 times.

Claims

1. an expansive concrete castinplace pile comprises reinforcing cage and builds the pile body that forms, and it is characterized in that: described pile body is formed bamboo knot shaped structure by ordinary concrete section of alternately building and expansive concrete section, and the expansive concrete section is thick than the ordinary concrete section.

2. according to the described expansive concrete castinplace pile of claim 1, it is characterized in that: the pile body bottom is also with the firming body that is formed by the cement slurry placing.

3. according to claim 1 or 2 described expansive concrete castinplace piles, it is characterized in that: the height of described ordinary concrete section and expansive concrete section is not less than 1000mm.

4. according to the described expansive concrete castinplace pile of claim 3, it is characterized in that: the height of described ordinary concrete section and expansive concrete section equates or is unequal.

5. according to the described expansive concrete castinplace pile of claim 4, it is characterized in that: every section of described pile body is highly equal or unequal.

6. according to the described expansive concrete castinplace pile of claim 5, it is characterized in that: the top of described pile body is the ordinary concrete section for one section.