JPS60115715A - Method and apparatus for formation of expanded head and tiered pile for cast-in-place pile - Google Patents

Abstract

PURPOSE:To easily construct an expanded head and tiered pile by a method in which excavation for pile pit and an expanded head of the pile is made until a given depth is reached, a width expansion blade is folded, and the excavation for the pile pit is continued. CONSTITUTION:A rod tube B is rotationally operated to excavate a pit of a diameter (d) by an excavating bit C, and excavation for expanded head of pile is concurrently made with a given interval by a head-expanding bit G. When a given depth (h) is reached by the bit G, the rod tube B is lifted up, the bit G is pulled up to the upper end of a stand pipe A, and a stopper bolt 6 is removed out. The rod tube B is hung down and again driven rotationally to complete excavation for the diameter (d) of the pile. An expanded head and tiered pile as a theoretically cast-in-place pile can be constructed economically and safely.

Description

[Detailed Description of the Invention] In general, the cast-in-place pile construction method first involves drilling an excavation hole with the required diameter and depth in the specified ground, then suspending and inserting reinforcing bar cages into the excavation hole, and pouring concrete into the holes. The purpose is to build the desired reinforced concrete pile by setting the concrete pile, and in order to make this formula easy, economical, safe, and theoretically cast-in-place pile, the wave crest expansion pile is constructed. .

This invention relates to the improvement of a head construction method and device.

The conventional construction method for expanding the head is to use a hammer club, etc. to create a standpipe A with the required expanded diameter.
After completing the excavation inside the standpipe by inserting it to a predetermined depth while removing earth and sand inside the standpipe, the method is used to drill a hole by inserting it into an excavation pit standpipe with a shaft diameter d. There is. In this case, if the required length of the pile head is deep, it may take an appropriate amount of time to insert the standpipe, and the geology may make it difficult to insert the standpipe.

It was considered a non-invention.

Next, the present invention will be explained in detail based on the illustrated embodiments and its construction method and apparatus. (b.

First, cast-in-place piles are built, and stand pipe A is placed at position 1. While excavating the earth and sand inside this stand pipe A using an L1 hammer club, etc., the stand pipe A is moved to a predetermined depth of 1.
Insert it. After completing the insertion of the stand pipe, a drilling bit C with diameter d at the tip of the rod pipe B is attached, and a stabilizer E and a weight F are sequentially connected and fixed on top of this pit. A pile head widening pit G having the diameter of the pile head is connected to the rod pipe above the top of the weight, and is driven to rotate through the rod pipe B. Rotating the rod pipe A hole with a shaft diameter d is excavated from the excavation pit CI at the tip of the rod pipe. Therefore, the drilling of the enlarged head diameter can be done at the same time. When this pile head widening pipe () () reaches a predetermined depth hr, the rotation of the rod pipe B is temporarily stopped, the pile head widening pipe) () is pulled to the upper end of the stand pipe A, and the upper stop ball trolley is removed. Then, the plurality of widening brackets 6 protruding radially from the outer periphery of the outer steel pipe 1 provided on the outer periphery of the rod pipe are folded down, and the rod pipe B is again suspended into the drilled hole. Rotate and drive to drill 4IllI Tsuzumi d.

In the above-mentioned structure of the pile head widening pin (G), the widening pin 3 is fitted into the outer steel pipe 1, and the excavation ≦ restrains the upward movement of the excavation blade 6, and 1 frees its downward movement.7? The mold notch 1a is provided, and the rib 21 is used to fix the rod pipe BI.
The lower ends of the ribs 2 are provided at both sides of the X3, with a spacing that allows the widening blades 6 to freely slide up and down, and the lower end of the rib 2 allows the widening blades 3 to be freely attached and detached by inserting the RC rotating shaft bolt 5 into the bold hole 4. A base protrusion 2a is provided, and a stopper ball is inserted into the bold hole 2b to prevent the descending of the widening material 3 during widening excavation. In addition, a width adjustment hole 4aG is provided so as to be able to cope with the reduction of the width of the enlarged head.

The outer lower Iglc of the widening blade 3 is provided with the required number of claws 3a to facilitate excavation, and has a structure in which the ribs 21 on both sides are narrowed by the bold holes 41m provided on the inside and can freely slide up and down by the rotating shaft bold 5. Eggplant.

Therefore, when the wave crest excavation proceeds five times at the same time and the head widening bit G reaches a predetermined depth, the rotation of the -U rod gB is stopped and the rod pipe B is rotated. Lift the pipe BG, pull up the pile head widening bit roll to the top of the stand pipe A, insert it into lip 2 2b, remove the locking ball toro, lower the widening wing 3 and fold it, then lower the rod pipes B and G. Then, the rotational drive is restarted, the trench of shaft diameter d (1t+p) is completed, and the pile head is expanded and the pile is constructed.

After completing the excavation of the shaft diameter d, a well-known bottom-expanding excavator is inserted and the bottom-expanding drill is carried out to construct a wave crest-expanding pile.

What is shown in No. 4 @ shows an example of an enlarged head that can be constructed using the construction method of the present invention. Figure (a) shows an enlarged head h,
This shows a wave crest expansion pile consisting of a shaft part Also, when the present invention is used, the standpipe Aid should be set to an appropriate length, and even if the pile head length is too large, Not only can construction be done easily, but the trouble of handling the pile head widening pit is omitted, which reduces the construction time accordingly. By making the K diameter of E the same diameter, the vertical end of the hole [7i
, - It also has many advantages, such as increasing the weight and also acting as a weight.

[Brief explanation of the drawings] Figure 1 shows the construction method of the present invention, the second figure shows the cross section (support) of the pile cap widening device, Figure 3 shows the same plan view, and the fourth side shows the construction method of the present invention. FIG. Aoo, stud pipe Bol, rod pipe C10, interaxial drilling bit Dol, pile head diameter dol, shaft diameter Eol, stabilizer F106 weight Gol, pile head widening bit 111. Outer steel pipe 1a01. Mold notch 2 +0. +1 pin 2a, , protrusion 2b, , bold hole 311. Widening wing 3a, , , claw 4!6. Bold hole 4J10. , widening adjustment hole 5101101 rotation shaft hold, stop bolt 7, . 7 Land Patent Publisher: Marugo Basic Industry Co., Ltd. Agent Kiyoaki Hayashi',:':,'9',,,:
. +1/ Outside 1 person IR Figure 1 Shin A Figure (ctn (Iy> Cc)]

Claims (2)

[Claims] (1) In I+Persue Method 1, a pile head widening pin is installed in advance on the top of the pile shaft hole drilling device, and the pile head widening is carried out at the same time as the pile shaft hole drilling progresses by rotating the rod pipe. ), when the pile cap widening excavation reaches the specified depth, −
Stop the rotation of the large rod pipe, lift the rod +f to the top of the pile head widening pit stand pipe, fold the widening blade, hang the rod pipe, and drill the pile shaft hole. A method for constructing stepped piles with widened pile heads in cast-in-place piles, which is characterized by continuously constructing stepped piles with widened pile heads. (2) An outer steel pipe having a slightly smaller diameter than the pile shaft hole diameter is fixed to the rod pipe with ribs, sandwiched between the ribs on both sides of the widening wing, and installed so that one widening wing can freely slide up and down, A construction device for a stepped pile with a pile head for widening in a cast-in-place pile, characterized in that the widening wing can be lowered and folded after completion of widening excavation.