JP2003184099A - Preventive force increasing method for preventive pile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem wherein a strength which concrete or the like filled in between a steel pipe pile and a boring hole or filled in a steel pipe pile holds is negrected. <P>SOLUTION: Protrusions such as reinforcements, etc., are welded or stuck in the manufacturing stage on the inner and outer peripheries of a steel pipe pile for preventing land slide, and a steel bottom cover is welded to the lower end of the steel pipe pile and erected in a boring hole (5). The erected steel pipe pile is adjusted to have a specified direction and depth and installed. Then, injection mortar or the like is charged in both inner and outer peripheries by a pump up to the mouth opening. After curing the mortar or the like, a top cover is welded to the upper end of the steel pipe pile. <P>COPYRIGHT: (C)2003,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preventing landslides, landslides, and the like, which increases the deterrent force of deterrent piles. 2. Description of the Related Art As shown in FIG. 1 and FIG. 2, a deterrent pile is used to bore a slipping soil mass to be activated to a stable ground by boring, and to put a pile into the boring hole to deter it. . [0003] The general construction method of the deterrent pile is as follows. Holes are drilled from the ground surface to the immovable ground through large-diameter boring, and steel pipe piles and H steel piles are built in the boreholes. The mortar or ready-mixed concrete is filled in or around the pile with a pump or the like. Then, the activity of the upper-level slipping soil mass is used to seek a reaction force on the immovable ground, and the landslide is suppressed using the pile as a cantilever. [0004] However, the following problems remain in the conventional deterrent piles. When landslide activities are deterred by piles, stability analysis is performed in advance to calculate the required deterrent.However, the strength of the mortar or ready-mixed concrete that fills the detent piles or fills the outer periphery is quite low. Estimates cannot be estimated. The reason is that when the landslide starts to work, the pile is bent and bent as shown in Fig. 1 and Fig. 2, and a tensile force acts on the mountain side (A) and a compressive force acts on the valley side (B). It is well known that hardened mortar and concrete materials are strong in compression but very weak in tension. The intensity difference is about 1/10 to 12. Therefore, the strength of the mortar or concrete material is calculated by ignoring the state of being subjected to the tensile action.
The mortar around the pile is filled only for the purpose of familiarizing with the ground, the expected strength of the mortar is about the same as that of the sliding soil mass, and concrete etc. packed inside the steel pipe pile is filled for corrosion protection of the steel pipe. I'm just there. Concrete is definitely cheaper than steel, but it is uneconomical. [0005] In view of the above problems, the present invention has been repeatedly studied and experimented. By maximizing the strength of concrete, which is inexpensive compared to steel, to increase the deterrence of piles, reduce the drilling depth and diameter of large-diameter boring, We studied how to reduce it. In other words, it provides a technology that can significantly reduce construction costs. [0006] From the above, the present invention described later cannot be applied to an active landslide, but not all landslides are always continuous and active. Sometimes slow down or stop. The occurrence of landslides and landslides is almost 100%, excluding earthquakes, and is caused by heavy rain or heavy rain. In other words, as a result of the rise of the groundwater level, the shear strength of the ground decreases and occurs. In addition, the sliding soil mass that has slipped is in a stable state even temporarily, although it will be active. This is even more so when sunshine continues and groundwater levels drop. Furthermore, the work to prevent steep inclines is mostly a precautionary measure for places where there is a possibility of collapse, and is not in operation. Therefore, there are many places where the present invention is employed. The inventor has devised the following method taking advantage of the properties of concrete and the like. As shown in FIG. 3, the bottom cover 1 is welded to the lower end of the pile.
0 was added. This is a very simple structure in which the reinforcing bars 8 and the like are welded to the inside and outside of the steel pipe pile 6 at equal intervals to form projections. When the slide soil mass 2 starts to operate, the steel pipe pile 6
When the thrust 22 acts on the steel pipe pile 6, the steel pipe pile 6 bends and bends. At this time, a tensile force 24 acts on the mountain side A of the steel pipe pile 6 and a compressive force 25 acts on the opposite valley side B. . And, the mountain side A of the concrete 7 inside and outside the steel pipe pile 6 easily generates a tensile crack and loses strength. However, on the contrary, it is also the result that the valley side B is slightly compacted. Therefore, when the reinforcing bar 8 and the like shown in FIG. 3 are present, the thrust 22 acts on the restraining pile 6 and when the pile 6 tries to bend, the concrete 7 on the valley side B is not compressed because the reinforcing bar 8 is hindered.
The concrete 7 on the mountain side A also cannot be stretched even if it is stretched because the reinforcing bar 8 is obstructed.
Cannot be deformed because it is surrounded on all sides. Accordingly, as long as the landslide activity thrust 22 does not exceed the restraining stress of the steel pipe pile 6 plus the compressive stress of the concrete 7, the deflection of the steel pipe pile 6 is kept to a minimum. That is, the deterrence of the steel pipe pile 6 is increased. Embodiments of the present invention will be described based on embodiments with reference to the drawings. In FIG. 3, the steel pipe pile 6
The projections such as the reinforcing bars 8 are welded at equal intervals inside or outside, or attached at the manufacturing stage. Then, a bottom lid is welded to one side of the steel pipe pile 6. Next, the steel pipe pile 6 is lifted into the boring hole 5 drilled by the large-diameter boring so that the bottom cover of the steel pipe pile 6 faces down, and built into the boring hole 5. Built steel pipe pile 6
Is installed at a predetermined direction and depth. Then, an injection hose is inserted between the steel pipe pile 6 and the boring hole 5, and mortar is filled with a pump. Mortar or ready-mixed concrete is filled in the steel pipe pile 6 to the mouth by the same pump. After confirming that the ready-mixed concrete has been filled and hardened to the mouth, the canopy is welded to the mouth of the steel pipe pile. When a horizontal loading test of steel pipe piles under various conditions was performed on the ground surface, the displacement of the restraining pile formed by reinforcing steel on the steel pipe pile was the smallest. That is, it was found that compressive strength of concrete can be expected by processing a reinforcing steel into a steel pipe pile. In other words, the deterrent of steel pipe piles is increased.
The same is true for H steel piles.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall cross-sectional view of a deterrent pile installed for landslide prevention. FIG. 2 is an up cross-sectional view of a deterrent pile installed for landslide prevention. FIG. 3 is a reinforcing bar inside and outside the deterrent pile. [Description of reference symbols] 1, ground surface 12-2, tension member (PC stranded wire, etc.) 2, slip mass 13, lever member 3, slip surface 14, fulcrum 4, immovable ground 15, working point 5 , Boring hole and hole wall 16, tension member U-turn head 6, steel pipe pile 17, tightening nut 7, mortar or ready-mixed concrete 18, wedge 8, rebar 19, rack gear 9, canopy 20, gear 10, bottom cover 21, Drum 11, compression plate 22, moving direction of thrust mass (thrust) 12, tension member 23, H steel pile 12-1, reinforcing bar (PC deformed steel bar, etc.) 24, tensile force A, tensile side 25, compressive force B , Compression side

[Procedure for Amendment] [Date of Submission] July 20, 2002 (2002.7.2
0) [Procedure amendment 1] [Document name to be amended] Description [Item name to be amended] Full text [Amendment method] Change [Content of amendment] [Document name] Description [Title of invention] Deterrent force of landslide prevention deterrent pile Up method Claims 1. Projections such as reinforcing bars (8) are attached to the inner and outer peripheries of a steel pipe pile (6) at the welding or manufacturing stage. Then, a steel bottom cover is welded to the lower end of the steel pipe pile (6), and a steel pipe pile (6) in which the bottom cover (10) and the reinforcing bar (8) are welded is built into the boring hole (5). The built-in steel pipe pile (6) is adjusted and installed in a predetermined direction and depth. Then, the inner and outer peripheries of the steel pipe pile (6) are filled with the injection mortar (7) and the like to the mouth by a pump. After curing the mortar (7) or the like, the canopy (9) is welded to the upper end of the steel pipe pile (6). Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pile for preventing landslides, landslides and other landslides. 2. Description of the Related Art As shown in FIGS. 1 and 2, a deterrent pile is made by drilling through a slip surface with a large-diameter boring, drilling to a stable immovable ground, and installing a steel pipe pile or an H steel pile. It is intended to control moving soil masses such as landslides by the shear and bending strength of the pile. Also, the mortar or concrete is filled into the inside and outer periphery of the pile with a pump or the like. [0003] However, the following problems remain in the conventional landslide prevention piles. First, when landslide activity is deterred by piles, stability analysis is performed in advance and the required deterrent force is estimated. However, the strength of the mortar and concrete filled inside and around the deterrent pile is not estimated at all in the calculation conditions. The reason is that when the moving mass of the landslide starts to move, the deterrent pile will bend to the valley side, the tensile force acts on the mountain side (A), and the compressive force acts on the valley side (B). In general, it is well known that hardened mortar and concrete are strong in compression and weak in tension. The difference in strength is about 1/10 to 10
It is set to 12. Therefore, the strength of the mortar or concrete material cannot be estimated as a trial calculation condition because the strength is lost due to tension. The mortar around the pile is filled for the purpose of familiarizing itself with the ground, and the mortar and concrete filled inside the steel pipe pile are filled for corrosion prevention of the steel pipe. Moreover, the quality of the filled mortar and the like was uneasy. Mortars are cheaper than steel, but they are uneconomical. [0004] In view of the above problems, the present invention has been repeatedly studied and experimented. As a means of increasing the deterrent of piles, the strength of mortar and concrete, which are cheaper than steel, is used to the maximum, the slope stability such as landslides is reduced, and the drilling depth and diameter are reduced. And
It is intended to provide economical landslide prevention technology that can significantly reduce construction costs. [0005] The problem in the deterrent pile,
Think back again. When the moving mass of the landslide is activated, the deterrent pile is deformed and bent to the valley side above the immovable ground by the thrust, and at the same time, the hardened mortar etc. in the steel pipe is pulled on the mountain side and cracks are cracked. Strength is lost. That is, when a thrust acts on the deterrent pile, the mortar or the like packed in the steel pipe becomes the force to receive the thrust, and the problem is solved if there is a method of preventing deformation. The present invention utilizes the properties of hardened mortar and the like to increase the deterrent of deterrent piles by the following method. A bottom cover (10) is welded to the lower end of the steel pipe pile (6), and a reinforcing bar (8) is welded to the inner and outer circumferences of the pile. Bottom cover (10)
And a steel pipe pile (6) with a reinforcing bar is suspended by a hoist or the like and built into a boring hole (5). Fill the inner and outer perimeters of the built steel pipe pile (6) with mortar (7) etc. to the mouth,
After curing the mortar, weld the canopy. [0009] In the landslide activity, a force is applied to the steel pipe pile (6),
The stake tries to deform. The force (tensile force acting on the pile hill side and compression acting on the valley side) is transmitted from the reinforcing bar (8) to the reinforcing bar (8) welded to the inner and outer peripheries of the steel pipe pile (6) ⇒ filled mortar (7), etc. From the mortar (7) etc. to the ground (2) via the hole wall. However, the hardened mortar (7) and the like are resistant to compressive force. In particular, since both ends of the steel pipe pile (6) are closed by lids, there is no escape for the force. Further, the force transmitted from the reinforcing bar (8) around the pile is dispersed and absorbed by the ground (2). Embodiments of the present invention will be described with reference to the drawings based on embodiments. In FIG. 3, protrusions such as reinforcing bars (8) are attached to the inner and outer peripheries of the steel pipe pile (6) at the welding or manufacturing stage. Then, a steel bottom cover is welded to the lower end of the steel pipe pile (6), and a steel pipe pile (6) in which the bottom cover (10) and the reinforcing bar (8) are welded is built into the boring hole (5). The built-in steel pipe pile (6) is adjusted and installed in a predetermined direction and depth. Then, the inner and outer peripheries of the steel pipe pile (6) are filled with the injection mortar (7) and the like to the mouth by a pump. After curing the mortar (7) or the like, the canopy (9) is welded to the upper end of the steel pipe pile (6). When a horizontal load test was conducted on a steel pipe pile, the displacement of the pile processed according to the present invention was much smaller than that of the conventional pile. That is, the steel pipe pile deterrence was improved by attaching a reinforcing bar to the inner periphery of the steel pipe pile or closing both ends of the pile. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall cross-sectional view in which a landslide prevention steel pipe pile is installed. FIG. 2 is an enlarged cross-sectional view in which a landslide prevention steel pipe pile is installed. FIG. 3 is an inner and outer periphery of the landslide prevention steel pipe pile. Cross-sectional view of rebar welding and lids welded to both ends of pile [Description of symbols] 1, Ground surface 2, Sliding moving mass 3, Slip surface 4, Immovable ground 5, Boring hole and hole wall 6, Steel pipe pile 7, Injection mortar Or concrete 8, steel bar 9, canopy 10, bottom lid 11, moving direction (thrust) of sliding soil mass 12, tensile force 13, compressive force A, tensile side B, compression side [Procedure 2] [Document name to be corrected] [Correction target item name] All drawings [Correction method] Change [Correction contents] [Fig. 1] FIG. 2 FIG. 3

Claims (1)

Claims: 1. Projections such as reinforcing bars 8 are welded to the inside and outside of a steel pipe pile 6 at equal intervals or attached at a manufacturing stage, and a bottom lid is welded to one side of the steel pipe pile 6 to form a boring hole. Build in 5. The inside and outside of the steel pipe pile 6 is filled with ready-mixed concrete or the like up to the mouth. After confirming that the ready-mixed concrete has been filled and hardened to the mouth, the canopy is welded to the mouth of the steel pipe pile.