KR20040073415A - Extracting casing after lower part curing type cast-in-place pile method - Google Patents

Abstract

PURPOSE: A casing drawing-type cast-in place pile method after concrete curing of a front end is provided to secure safety of the pile foundation and the whole structure by precisely constructing a cast-in place pile regardless of conditions of the ground. CONSTITUTION: A casing drawing-type cast-in place pile method after concrete curing of a front end comprises steps for forming an excavating hole in a sediment layer(11) by intruding a casing(30) and excavating the sediment contained in the casing with a sediment excavator(S10); pulling out the sediment excavator with leaving the casing to keep a borehole after completing the excavation to a planned penetration(S20); forming the front end of the pile by pouring concrete(33) into the casing and drawing the casing at the predetermined distance to closely contact the lower end of the casing and the surface of the concrete(S41); preventing the settlement of the casing by mounting a casing support(50) on the casing exposed to the ground, putting a stiffener(31) in the casing after mounting a stiffener support(40) to the upper end of the casing, and fixing the upper end of the stiffener to the upper end of the casing through the stiffener support(S42); curing the front end of the pile with fixing the casing and the stiffener by the casing and stiffener supports(S43); and dismantling the stiffener and casing supports after completing the curing of the front end and forming a pile body by pulling out the casing, injecting a filler(34) in the casing, and filling the excavating hole(S51).

Description

Casing drawing-in-place pile pile method after curing of the tip part {EXTRACTING CASING AFTER LOWER PART CURING TYPE CAST-IN-PLACE PILE METHOD}

In the present invention, when constructing a field-placed pile in which reinforcement materials such as steel frame or reinforcing steel are embedded, once the concrete is poured at the tip of the pile, the reinforcement and the casing are fixed to the ground, and curing is completed. By constructing the rest of the pile, by preventing the position of the reinforcing material is changed during the curing of the pile, it is possible to precise construction of the cast-in-place pile.

The cast-in-place pile is a kind of pile foundation in contrast to the ready-made pile, and it is composed by pouring concrete into the pre-drilled excavation hole and curing it. Since the process is unnecessary, there is an advantage that can prevent the noise or vibration caused during the driving process.

In general, pile foundations are resistant to negative pressure of underground structures due to the load of the upper pile structure or groundwater due to the tip bearing and main surface frictional forces, thus securing the excavation depth beyond the rock layer or the rock layer being too deep. In this case, it is necessary to secure near-term entry length.

FIG. 1 shows a process of constructing a cast-in-place pile in a typical ground composed of a soil layer 11 and a rock layer 12, injecting the gasket 30, and the earth and sand inside the casing 30 with the earth excavation equipment 21. As shown in FIG. Excavation to excavate the earth and sand layer excavation step (S10) to form an excavation hole in the soil layer (11), rock excavation to the rock layer (12) is completed excavation to pull out the earth excavation equipment 21 while leaving the casing 30 so that the empty wall is maintained Equipment drawing step (S20), the rock bed excavation bit 22 into the casing 30 to excavate the rock bed layer 12 rock bed layer excavation step (S30), reinforcing materials such as steel or steel in the excavation hole formed in the rock bed layer 12 Reinforcement input step (S40) for inserting the 31, the concrete pouring step (50) and poured concrete to cast the concrete (33) into the casing (30) through the tremis tube (32) while drawing the casing (30) Curing (33) consists of a curing step (S60) to complete the pile.

In some cases, without drilling the rock layer 12, the steel frame is mounted in the casing 30, and then driven to drive the steel frame, which is a reinforcing material 31 to the rock layer 12, as described above. In the case that the depth of the stiffener is not easy to fix the tip of the pile during construction, that is, when the bottom of the stiffener 31 is easily fixed due to the rock layer 12 when the stiffener 31 is introduced into the casing 30. Since the displacement of the reinforcing material 31 during the casting and curing process of the concrete 33 for constituting the body of the cast-in-place pile is minimal, construction of high precision is possible.

However, as shown in Figure 2, when the construction site on the ground consisting of only the soil layer (11) when the pile is placed and the position or angle of the reinforcement 31 is very likely to change during the curing and curing of the concrete 33, Therefore, not only the precise construction is difficult, but also the safety factor is increased to secure the bearing capacity, so there is a serious problem that the construction cost is increased due to the overdesign and the overconstruction.

Particularly, in the case of forming an enlarged portion for securing bearing capacity at the pile tip regardless of the soil layer 11 and the rock layer 12, the possibility of displacement of the reinforcement 31 during the casting and curing process of the concrete 33 is further increased. But there was a serious threat to the safety of the ground structure.

The present invention has been devised in view of the above-described problems, in constructing a site-placement pile into which the reinforcement is embedded, curing the reinforcement and the casing in a state where the reinforcement and the casing are fixed to the ground surface after placing the tip of the pile while drawing the casing slightly. When curing is completed, the excavation hole is filled with a filler such as concrete, sand, or crushed stone to form the remainder of the pile, thereby preventing the position of the reinforcement during the curing of the pile.

The upper part of the casing which is narrowly drawn is installed with a casing support configured to disperse the weight of the casing on the ground to prevent settlement of the casing during curing, and the upper part of the casing secures reinforcing materials such as steel or steel reinforced into the casing. The reinforcement support was installed to prevent displacement of the reinforcement during curing.

1 is an explanatory diagram of a conventional cast-in-place pile method in general ground conditions

2 is an explanatory diagram of a conventional cast-in-place pile method in the soil layer

Figure 3 is an illustration of an embodiment of the present invention

Figure 4 is a detailed view of the head of the curing pile in an embodiment of the present invention

5 is an exploded perspective view of a pile under construction in an embodiment of the present invention;

Figure 6 is a detailed view of the pile tip being cured in the present invention

Figure 7 is a state of reinforcement input of the present invention.

<Code Description of Main Parts of Drawing>

11: soil layer

12: rock bed

21: Earth excavation equipment

22: rock drilling bit

30: Casing

31: reinforcement

32: Tremie pipe

33: concrete

34: charging body

40: reinforcement support

41: frame

42: fixed plate

43: set screw

50: casing support

51: flat flange

52: close contact

53: Tightening Screw

S10: earth excavation stage

S20: Excavation Equipment Drawing Step

S30: rock bed excavation stage

S40: Reinforcement input step

S41: Tip placement step

S42: reinforcement finance stage

S43: Tip curing stage

S50: Concrete pouring step

S51: main body charging step

S60: Curing Stage

The detailed configuration of the present invention through the accompanying drawings as follows.

As shown in FIG. 3, first, inject the gasket 30 and excavate the earth and sand inside the casing 30 by forming the excavation hole in the earth and sand layer 11, and when the excavation is completed to the planned depth. The excavation equipment 21 is drawn out while the casing 30 is left to maintain the empty wall. The process up to this point is the same as the conventional method described above with reference to FIG. 2.

When the formation of the excavation hole is completed, while drawing the casing 30 slowly, the concrete 33 is poured into the casing 30 to form the tip of the pile, wherein the drawing speed of the casing 30 and the concrete 33 Adjusting the pouring speed and the amount so that the lower end of the casing 30 is adjacent to the upper surface of the poured concrete (33).

As such, when pouring concrete 33 to form the tip of the pile, the lower end of the casing 30 is not completely spaced from the poured concrete 33 or penetrated into the concrete 33, and the reason for keeping the adjacent wall is a hollow wall (孔 壁). At the same time to maintain the, so that the concrete 33 is not attached to the casing 30 in the later curing process.

In particular, in the curing process after the pile tip portion is completed, when the lower end of the casing 30 is embedded in the concrete 33, the casing 30 is not drawn, or the cured pile tip portion is drawn together with the casing 30 In particular, in order to prevent this phenomenon, it is preferable to construct the concrete 33 and the casing 30 so as to be slightly spaced apart from each other.

When the pouring of concrete 33 for the pile tip configuration is completed, the casing support 50 is installed on the upper portion of the casing 30 exposed on the ground so that the casing 30 does not settle and the upper end of the casing 30 After the reinforcement support 40 is installed, as shown in FIG. 7, the reinforcement 31 is introduced into the casing 30 while maintaining the correct position and posture through the reinforcement support 40.

The casing support 50 is for preventing the casing 30 from sinking during the curing process of the pile tip concrete 33. The casing support 50 is fixed to the upper portion of the casing 30 exposed to the ground to ground the weight of the casing 30. And an embodiment thereof are shown in FIGS. 4 and 5.

The casing support 50 of the illustrated embodiment has a contact portion 52 and an upper surface formed such that one surface thereof coincides with the outer circumferential surface of the casing 30, and a bottom surface is joined to the lower portion of the contact portion 52 and the bottom surface thereof is in contact with the ground. Consists of a flat flange 51, the pair of casing support 50 is symmetrical to the casing 30 is fastened tightly fixed, fastening screw 53 is configured to enable fast fastening and disassembly. .

4 and 5, the embodiment is shown in the reinforcement support 40, by fixing the upper end of the reinforcing material 31, such as steel frame or reinforcing steel during the curing of the pile tip concrete 33 to the upper end of the casing 30, In addition to the role that the position or angle of the 31 is not changed, as described above, when the reinforcing material 31 is introduced into the casing 30, the reinforcing material 31 introduced by guiding the feeding path is poured into concrete. 33, it will also play a role in intruding into the correct position and posture.

The reinforcing material support 40 of the illustrated embodiment is composed of a rectangular frame 41 fixed to the upper casing 30 by a fixing screw 43 and a pair of parallel fixing plates 42 installed on the frame 41 and the like. , It is configured to adjust the interval between the two fixing plates 42 according to the dimensions of the reinforcing material 31 is inserted, it is installed after cutting the upper end of the partially drawn casing (30) when the concrete 33 is placed.

As such, when curing of the tip portion is completed in the state of fixing the reinforcing material 31, the reinforcing material support 40 and the casing support 50 are dismantled and the casing 30 is pulled out while the concrete 33, sand, and crushed stone are inside the casing 30. The main body of the cast-in-place pile is formed by filling the excavation hole by injecting the filler 34 such as the back.

3 shows that the concrete 33 is applied as the filler body 34, and the poured concrete 33 is completed with a pile through a curing period of a predetermined period, and then, tofu, etc. After the post-treatment process.

As a result, the technical gist of the present invention, in the construction method of the site-placed pile in which the reinforcement 31 is embedded, penetrates the casing 30 and excavates the earth and sand inside the casing 30 with the earth excavation equipment 21. 11) the excavation layer (S10) to form an excavation hole, and excavation equipment drawing step (S20) to pull out the excavation excavation equipment 21 while leaving the casing 30 so that the empty wall is maintained when excavation is completed to the planned depth And to cast the predetermined amount of concrete 33 into the casing (30) to form the tip of the pile, but to draw the casing (30) a predetermined distance so that the lower end of the casing (30) and the surface of the cast concrete 33 is adjacent to the casing (30) Install the casing support 50 on the tip portion placing step (S41) and the upper portion of the casing 30 exposed on the ground, so that the casing 30 does not settle, and the reinforcing material support 40 on the upper end of the casing 30 After installation, the reinforcing material 31 is put into the casing and the reinforcing material is supported. Reinforcing step (S42) for fixing the upper end of the reinforcing material 31 to the upper end of the casing 30 through the (40), the casing 30 and through the casing support 50 and the reinforcing material support (40) The tip curing step (S43) for curing the tip of the pile in a state in which the reinforcing material 31 is fixed, and when the curing of the tip is completed, the reinforcing member support 40 and the casing support 50 are dismantled and the casing 30 is drawn out. (30) Injecting the filling body 34 to fill the excavation hole by filling the excavation hole, the body filling step (S51) comprising the casing pull-out casing pull-out method after curing the front end portion, characterized in that the casing support 50 is a pair of close contact portion 52 formed so that one surface coincides with the outer circumferential surface of the casing 30, the upper surface is joined to the lower end of each contact portion 52, the bottom surface of the plate-like (하는) in contact with the ground It is fastened between the flat plate flange 51 and each contact portion 52 A plurality of front end after curing, characterized by consisting of a fastening screw (53) is a casing drawn expression Drilled method.

By improving the precision of the cast-in-place pile through the present invention, it is possible to obtain the effect of ensuring the safety of the entire structure, including the foundation, and in particular, it is possible to precise construction regardless of the ground conditions, overdesign and construction for securing the safety factor Improving practices can also reduce the cost of construction.

Claims (2)

In the construction method of the cast-in-place pile in which the reinforcing material 31 is embedded, A soil layer excavation step (S10) of injecting the gasket 30 to excavate the soil inside the casing 30 with the soil excavation equipment 21 to form an excavation hole in the soil layer 11; Excavation equipment drawing step (S20) for drawing the earth excavation equipment 21 while leaving the casing 30 to maintain the empty wall when the excavation is completed by the planned depth; A predetermined amount of concrete 33 is poured into the casing 30 to form a tip end of the pile, but a tip end casting for drawing the casing 30 a predetermined distance so that the bottom of the casing 30 and the surface of the poured concrete 33 are adjacent to each other. Step S41; The casing support 50 is installed on the upper part of the casing 30 exposed on the ground so that the casing 30 does not settle, and the reinforcing material support 40 is installed on the upper end of the casing 30, and then the reinforcing material 31 is provided. A reinforcing step (S42) for putting the inside of the casing and fixing the upper end of the reinforcing material 31 to the upper end of the casing 30 through the reinforcing material support 40; A tip curing step (S43) for curing the tip of the pile in a state where the casing 30 and the reinforcing material 31 are fixed through the casing support 50 and the reinforcing material support 40; When curing of the front end is completed, the pile body is formed by dismantling the reinforcing material support 40 and the casing support 50, and filling the excavation hole by injecting the filling body 34 into the casing 30 while drawing the casing 30. Casing-pulling on-site casting method after the end portion curing, characterized in that the main body charging step (S51) is included. According to claim 1, the casing support (50) and a pair of close contact portion 52 formed so that one surface and the outer peripheral surface of the casing (30); An upper surface is joined to the lower end of each contact portion 52, and a lower surface of the plate-like flat flange 51 is in contact with the ground; Casing pull-in-place pile method after the end portion curing, characterized in that it consists of a plurality of fastening screws 53 fastened between each of the close contact portion (52).