Polymer grouting method for constructing multi-wing pile

Abstract

A polymer grouting method for constructing multi-wing pile, includes steps of: (1) arranging the positions of piles; (2) producing multi-wing drilling tool and locating holes; (3) installing grouting pipes; (4) polymer lifting grouting; (5) forming polymer multi-wing piles. According to the geologic characteristics, the three-wing drilling tool or the four-wing drilling tool are produced through pressing the drilling tool into each location of pile by a static pressure equipment to form the multi-wing holes, and injecting two-component expansive polymer materials to the holes, wherein the polymers expand and solidify after reacting for filling the holes and the gaps in the soil of slope to be fully integrated with the surrounding soil and form the polymer multi-wing piles.

Description

BACKGROUND OF THE PRESENT INVENTION

1. Field of Invention

The present invention relates to a field of slope protection and landslide control, and more particularly to a polymer grouting method for constructing multi-wing pile relating to a field of slope protection of roads and landside control.

2. Description of Related Arts

Geological disasters occur frequently in China, wherein the number of dead and missing caused by geological disasters accounts for about ⅓ of the total number of disasters, and the cost of direct economic loss are as high as billions of dollars, wherein landslide is the geological disaster which occurs most frequently and is most harmful, wherein the number thereof is 50%-60% of the total number of geological disasters. Once the landslide disasters occur, traffic is interrupted, channels are congested, factories are destroyed, and villages are buried, serious life and property loss and environmental damage are caused. In recent years, with the rapid development of economic construction and human engineering activities in China, the frequency and scale of the landslide disasters increase year by year, it is a serious threat to people's lives and property and the production of industry and agriculture. Therefore, the prevention and control of landslide disaster and the active exploration of new material, new technology and new equipment in landslide disaster treatment have become important tasks to be solved.

Landslide is a phenomenon of rock and soil overall sliding along one or more weakness surfaces of slope under the action of gravity. The factors of inducing the landslide are various, wherein the geological structure and physic-mechanical property of the rock and soil on slope are the internal causes, wherein rainfall, underground water level change, and human engineering activities are the external causes. The formation process of landslide is the result of interaction.

Aiming at the factors of inducing the landslide, 5 ways of conventional treatments of landslide comprise: removing the rock and soil of landslide, establishing drainage project, improving the rock and soil on slope, reducing pressure and establishing retaining project. It is economical for the small scale landslides to remove the rock and soil of landslide through the excavation work but not the big scale landslides; establishing drainage project is an indirect control measure, wherein underground water and surface water are guided to the natural channels through building drainage and cut-off system at the inside and outside of the landslide respectively for avoiding landslide caused by that the rock and soil of slope is weakened when encountering water and its strength is sharply dropped down; improving the rock and soil on slope is also an indirect control measure, wherein the properties of the rock and soil on slope are improved by electro-osmosis, calcinations, and chemical grouting to increase the strength and anti-sliding ability; reducing pressure is a way which unloads at the top of the slope and loading at the bottom of the slope for decreasing the strength, for improving the anti-sliding force and the stability of slope, wherein it is suitable to the small and medium scale landslides, and the design and construction are simple but it is only used in earthwork, wherein the pre-condition for using is the mechanical equipments are easy to be stationed in the construction plant, or the labor intensity is high and the efficiency is low; wherein establishing retaining project is a way which increases the anti-sliding ability through building the retaining structure to stabilize the rock and soil of slope. The common forms of retaining wall comprise anti-sliding retaining walls, pre-stressed anchor rods (or anchor cables) and anti-sliding piles. Anti-sliding retaining walls are positioned at a bottom of the slope, it is suitable to treat the slopes which is small-scale and has small sliding thrust; pre-stressed anchor rods (or anchor cables) are used in reinforcing rock slopes but it is hard to used in reinforcing soil slopes; anti-sliding piles are widely used in treating different scales of slopes.

Among the ways of conventional treatments of landslide, establishing retaining project is the most effective and direct, and the earth quantity is smallest, wherein anti-sliding piles are favored by engineers because of the characters such as great anti-sliding, flexible pile position and strong applicability. The pile body of anti-sliding piles goes deeply into the slope through a sliding surface, wherein a landslide thrust is passed to the stable formation by the combination of pile and surrounding rock and soil, wherein the landslide thrust is balanced by the effect of anchoring and passive resistance to improve the state of landslide and stabilize the landslide.

Anti-slide piles comprise driven piles, bored piles and digging piles according to the method of construction, wherein anti-slide piles comprise timber piles, steel piles, and reinforced concrete piles according to the material, wherein the shapes of section can be circular, tubular and rectangular. Anti-slide piles have many significant advantages such as: (1) high anti-slide capacity, which has more obvious advantage than the retaining wall which resists the slide force under an action of gravity through a resistance produced by embedding the piles into stable layer; (2) flexible pile position, which can be set at the position which is the most anti-sliding, wherein it can be used individually or be combined with the retaining structure such as anchor rods and anchor cables, wherein the huge landslide can be cut into several units to treat separately when the anti-slide piles are set in lines; (3) strong applicability, which can be used in different scales and types of slide treatment; (4) checking the geology directly through digging the pile holes to modified the original design.

Though the advantages of anti-slide piles are outstanding, there are still some shortcomings which are hard to overcome with respect to the demand of landslide treatment, comprising: (1) large disturbance to the slopes when digging the holes by machines or human, wherein the landslide state is easy to worsen especially when using the driven piles; (2) complicated process, slow construction speed, high labor intensity and low efficiency, wherein mud and concrete retaining wall is needed when using machines to dig holes, wherein it is hard to meet the demand of emergency rescue; (3) large equipments, high energy consumption and poor applicability, wherein it is hard to enter and set up the machines in the steep slope engineering; (4) long construction period, huge material consumption and high cost; (5) poor durability of timber piles and steel piles, and large difference between the elasticity modulus of the reinforced concrete piles and soil, wherein the reinforced concrete piles and soil are easy to cracked because of the low deformation coordination; (6) polluting the environment because a number of effluent and waste are produced in the cement concrete pile construction process.

Therefore, anti-slide piles are most widely used in landslide treatment, but there are still some shortcomings which are hard to overcome with respect to the current demand of landslide prevention and control, comprising: large disturbance to the slopes, long construction period, high cost and complicated process. Thus, developing new materials, new technologies and new equipments of landslide disaster treatment which are efficient and cheap are of great importance to prevent and control landslide disaster and protect people's lives and property.

Polymer grouting technology is the foundation reinforcement technique quickly developed in the 1970s. It reinforces the foundation and fills the gaps through grouting polymers to the foundation, wherein the polymers expand and solidify after reacting. At present, polymer grouting technology is widely used in the foundation reinforcement of industrial and civil structures, wherein the polymer grouting method for constructing multi-wing pile has not been used to treat landslide in China.

SUMMARY OF THE PRESENT INVENTION

Aim to the shortcomings of landslide treatment specially that high cost, low construction speed and large disturbance to slopes which are hard to meet the demand of emergency rescue, the present invention is to provide a polymer grouting method for constructing multi-wing pile which is easy, cheap, safe and environmental protecting. The present invention is to provide an advanced, efficient, safe and suitable method to achieve the landslide treatment.

Accordingly, in order to accomplish the above objects, the present invention provides a polymer grouting method for constructing multi-wing pile, comprising the steps of:

• • (1) arranging positions of piles, comprising: arranging the positions on a slopes which need be treated according to design;
  • (2) producing a multi-wing drilling tool and locating multi-wing holes, comprising: producing drilling tool and press the drilling tool for an expected depth to form the multi-wing holes at each location of pile according to the design;
  • (3) installing grouting pipes, comprising: installing grouting pipes in the multi-wing holes, wherein the grouting pipes are provided at centers of the multi-wing holes, wherein outlets of grouting pipes are provided at bottoms of the multi-wing holes;
  • (4) polymer lifting grouting, comprising: providing a grouting control equipment for lifting polymer on tops of the multi-wing holes, providing the grouting pipes into a pipe fixing device of the grouting control equipment for lifting polymer, injecting two-component expansive polymer materials through the grouting pipes of the polymer grouting system into the multi-wing holes, and turning on the grouting control equipment for lifting polymer at the same time; and
  • (5) forming polymer multi-wing piles, comprising: lifting the grouting pipes according to a set rate, wherein the polymer materials expand and solidify after reacting for filling the multi-wing holes and gaps in the soil of slope to be fully integrated with the surrounding soil and form the polymer multi-wing piles.

In step (2), the multi-wing drilling tool is combined with a drill stem and wings welding on a circumference of the drill stem, wherein a diameter D of cone probe of the drill stem is 40-80 mm, wherein the wings of the drill stem are triangular steel plates welding blades, wherein a highness H of the wings is 100-400 mm, an angle α between a base of the wings and the drill stems is 30-45 degrees, a thickness T of the wings is 10-30 mm.

The multi-wing drilling tool comprises a three-wing drilling tool and a four-wing drilling tool.

According to the geologic characteristics of project, the three-wing drilling tool and the four-wing drilling tool are produced. Through pressing the drilling tool into each location of pile to form the multi-wing holes, and injecting two-component expansive polymer materials into the multi-wing holes, the polymers expand and solidify after reacting for filling the multi-wing holes and the gaps in the soil of slope to fully integrated with the surrounding soil and form the polymer multi-wing piles with strong anti-slide ability.

Compared with conventional technology of anti-slide piles, the present invention has the advantages comprising:

• • (1) Non-water reaction, which has high applicability; it is suitable to be used in the landslide disaster rescue for the different scales of landslide because of the polymer multi-wing piles which can be constructed rapidly to form an anti-sliding retaining structure system. The non-water reacted polymer does not shrink, which has great tensile, anti-vibrating and anti-crack properties, wherein the volume expansion rate is large, the shape of pile can fulfill the multi-wing holes, wherein it is not only suitable to the soil and the slope protection but also the landslide treatment which the cement base is not suitable to;
  • (2) high anti-pulling and anti-shearing; the contact area between the pile and surrounding soil of polymer multi-wing pile is bigger than the pile that the section is circle or rectangle which improves the anti-pulling and the anti-shearing;
  • (3) small disturbance to slope; the disturbance to slope is small to the slope through pressing the drilling tool into each location of pile to form the multi-wing holes and anhydrous reacting;
  • (4) fast constructing, no need to be cured; the construction is fast because of the continuous operation of drilling and lifting; About 90% of the strength is formed after the reaction of material for 15 minutes;
  • (5) low cost; the cost of polymer multi-wing pile technology can save 50% of the cost compared with the conventional anti-sliding technology;
  • (6) easy constructing; the series of polymer grouting equipment can be used in different construction plants, the stationing is convenient and the power consumption is small;
  • (7) great durability; the polymer grouting material has stable property, non-pollution, good flexibility, closely combined with the rock and soil of the slope, compatible deformation, small osmotic coefficient, great resistance to chemical corrosion and anti-penetrability performance when being buried underground for a long time.

Therefore, the present invention has serious advantages in the landslide treatment. The polymer grouting method for constructing multi-wing pile is a newer set of technologies compared with the conventional technology, mainly in:

• • (1) the aspect of the material of pile and the idea of pile-forming, wherein non-water reacted polymer grouting materials are used in the polymer grouting method for constructing multi-wing pile, according to the idea of flexible pile-forming, which is safe, environmental protecting and light, and has high expansion rate, great anti-permeability and early strength. The polymer multi-wing piles are flexible, firmly gluing with the soil, wherein the deformation is harmonious, the properties of anti-permeability and anti-crack are great;
  • (2) the aspect of the mechanism of treatment, wherein the polymers expand and solidify after reacting for filling the multi-wing holes and the gaps in the soil of slope to be fully integrated with the surrounding soil and form the polymer multi-wing piles to realize rapidly stabilizing the sliding slope;
  • (3) the aspect of the mode of construction, wherein polymer multi-wing piles are formed through pressing the drilling tool into each location of pile by a static pressure equipment and polymer lifting grouting method to form the multi-wing holes, which realizes a easy construction, wherein it achieves rapid landslide treatment and small disturbance to the slope;
  • (4) the aspect of the shape of pile, comprising: substituting the shape which is circle or rectangular for the shape which is multi-wing pile, which improves the anti-pulling and the anti-shearing ability thereof.

Therefore, there are obvious differences between the invention and the conventional anti-sliding pile technology according to the aspect of the material of pile and the idea of pile-forming, the aspect of the mechanism of treatment, the aspect of the mode of construction, and the aspect of the shape of pile, wherein it has the advantages of great adaptability, fast speed, light weight, high tenacity, cheap cost and durable in use, and has a great development prospect in economy and social benefit.

These and other objectives, features, and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a vertical view of a multi-wing drilling tool.

FIG. 2 is a top view of the multi-wing drilling tool.

FIG. 3 is a schematic diagram of pressing the drilling tool into each location of pile to form the multi-wing holes.

FIG. 4 is a schematic diagram of polymer lifting grouting.

FIG. 5 is a section view of a polymer multi-wing pile.

FIG. 6 is a top view of the polymer multi-wing pile.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A polymer grouting method for constructing multi-wing pile according to a preferred embodiment of the present invention is illustrated, comprises the steps of:

• • (1) arranging positions of piles, comprising: arranging the positions on slope which need be treated according to design;
  • (2) producing a three-wing drilling tool and locating the holes, comprising: producing the three-wing drilling tool 1, the three-wing drilling tool 1 is combined with a drill stem 1-1 and three wings 1-2 welding on a circumference of the drill stem 1-1, wherein a diameter D of cone probe of the drill stem 1-1 is 40-80 mm, wherein the diameter D of cone probe can be 40 mm, 50 mm, 65 mm, 75 mm, or 80 mm, wherein the wings 1-2 are triangular steel plates welding blades, wherein a highness H of the wings 1-2 is 100-400 mm, wherein the highness H of the wings 1-2 can be 100 mm, 200 mm, 350 mm, or 400 mm, i.e., any value between 100-400 mm, wherein an angle α between a base of the wings 1-2 and the drill stem 1-1 is 30-45 degrees, a thickness T of the wings 1-2 is 10-30 mm, wherein an angle β between two adjacent wing 1-2 of the three-wing drilling tool 1 is 120 degrees, wherein the three-wing drilling tool 1 are pressed into each location of pile for an expected depth by a static pressure equipment 2 to form three-wing holes 3 according to the design;
  • (3) installing grouting pipes, comprising: installing grouting pipes 4 in the three-wing holes 3, wherein the grouting pipes 4 are provided at a center of the three-wing holes 3, wherein outlets of the grouting pipes 4 are provided at a bottom of the three-wing holes 3;
  • (4) polymer lifting grouting, comprising: providing a grouting control equipment 5 for lifting polymer on a top of the grouting pipes 4, providing the grouting pipes 4 into a pipe fixing device of the grouting control equipment 5 for lifting the polymer, injecting two-component expansive polymer materials 6 through the grouting pipes 4 of the polymer grouting system into the three-wing holes 3, and turning on the grouting control equipment 5 for lifting polymer at the same time;
  • (5) forming polymer three-wing piles, comprising: lifting the grouting pipes according to a set rate of 8 cm/s, wherein the two-component polymer materials expand and solidify after reacting for filling the three-wing holes and the gaps in the soil of slope to be fully integrated with the surrounding soil and form three-wing polymer piles 7.

The grouting method of polymer multi-wing according to another preferred embodiment of the present invention is illustrated, comprises the steps of:

• • (1) arranging positions of piles, comprising: arranging the positions on slope which need be treated according to design;
  • (2) producing a four-wing drilling tool and locating the holes, comprising: producing the four-wing drilling tool 1, the four-wing drilling tool 1 is combined with a drill stem 1-1 and four wings 1-2 welding on a circumference of the drill stem 1-1, wherein a diameter D of cone probe of the drill stem 1-1 is 40-80 mm, wherein the diameter D of cone probe can be 40 mm, 50 mm, 65 mm, 75 mm, or 80 mm, wherein the wings 1-2 are triangular steel plates welding blades, wherein a highness H of the wings 1-2 is 100-400 mm, wherein the highness H of the wings 1-2 can be 100 mm, 200 mm, 350 mm, or 400 mm, i.e., any value between 100-400 mm, wherein an angle α between a base of the wings 1-2 and the drill stem 1-1 is 30-45 degrees, a thickness T of the wings 1-2 is 10-30 mm, wherein an angle β between two adjacent wings 1-2 of the four-wing drilling tool 1 is 90 degrees, wherein the four-wing drilling tool 1 are pressed into each location of pile for an expected depth by a static pressure equipment 2 to form four-wing holes 3 according to the design;
  • (3) installing grouting pipes, comprising: installing grouting pipes 4 in the four-wing holes 3, wherein the grouting pipes 4 are provided at a center of the four-wing holes 3, wherein outlets of the grouting pipes 4 are provided at a bottom of the four-wing holes 3;
  • (4) polymer lifting grouting, comprising: providing a grouting control equipment 5 for lifting polymer on a top of the grouting pipes 4, providing the grouting pipes 4 into a pipe fixing device of the grouting control equipment 5 for lifting the polymer, injecting two-component expansive polymer materials 6 through the grouting pipes 4 of the polymer grouting system into the four-wing holes 3, and starting the grouting control equipment 5 for lifting polymer at the same time;
  • (5) forming polymer four-wing piles, comprising: lifting the grouting pipes according to a set rate of 8 cm/s, wherein the two-component polymer materials expand and solidify after reacting for filling the four-wing holes and the gaps in the soil of slope to be fully integrated with the surrounding soil and form four-wing polymer piles 7.

One skilled in the art will understand that the embodiment of the present invention as shown in the drawings and described above is exemplary only and not intended to be limiting.

It will thus be seen that the objects of the present invention have been fully and effectively accomplished. Its embodiments have been shown and described for the purposes of illustrating the functional and structural principles of the present invention and is subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.

Claims

1. a polymer grouting method for constructing multi-wing pile, comprising steps of:

(1) arranging positions of piles, comprising: arranging said positions on slopes which need be treated according to a design;

(2) producing a multi-wing drilling tool and locating multi-wing holes, comprising: producing said multi-wing drilling tool and press said multi-wing drilling tool for an expected depth to form said multi-wing holes at each location of pile according to said design;

(3) installing grouting pipes, comprising: installing said grouting pipes in said multi-wing holes, wherein said grouting pipes are provided at a center of said multi-wing holes, wherein outlets of said grouting pipes are provided at a bottom of said multi-wing holes;

(4) polymer lifting grouting, comprising: providing a grouting control equipment for lifting polymer on a top of said multi-wing holes, providing said grouting pipes into a pipe fixing device of said grouting control equipment for lifting polymer, injecting two-component expansive polymer materials through said grouting pipes of said polymer grouting system into said multi-wing holes, and turning on said grouting control equipment for lifting polymer at the same time;

(5) forming polymer multi-wing piles, comprising: lifting said grouting pipes according to a set rate, wherein said polymer materials expand and solidify after reacting for filling said multi-wing holes and gaps in said soil of slope to be fully integrated with a surrounding soil and form said polymer multi-wing piles.

2. The polymer grouting method for constructing multi-wing pile, as recited in claim 1, wherein, in step (2), said multi-wing drilling tool is combined with a drill stem and multi-wings welding on a circumference of said drill stem, wherein a diameter D of cone probe of said drill stem is 40-80 mm, wherein said multi-wings are triangular steel plates welding blades, wherein a highness H of said multi-wings is 100-400 mm, wherein an angle α between a base of said multi-wings and said drill stem is 30-45, wherein a thickness T of said multi-wings is 10-30 mm.

3. The polymer grouting method for constructing multi-wing pile, as recited in claim 2, wherein said multi-wing drilling tool comprises a three-wing drilling tool and a four-wing drilling tool.