JP2002129561A - Construction method for driven pile, jointly using vibration and pressure water injection - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a construction method for a driven pile, jointly using vibrations and pressure water injection, having an execution management method for enabling the reliable acquirement of a prescribed bearing capacity while allowing for an influence on a ground. SOLUTION: In the construction method for the driven pile, the vibrations generated by a vibration hammer are combined with the pressure water injection given by a water jet. In the layer region wherein the driven pipe having the execution management method manifests an end bearing capacity, the output of the vibration hammer is kept within a prescribed range, and the pressure water injection is controlled. In the layer region wherein skin friction manifests itself, the pressure water injection is adjusted so as to allow the output of the vibration hammer to be kept within the prescribed range.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the field of pile driving method for steel pipe piles and steel pipe sheet piles. In particular, the present invention relates to a vibratory driving pile method combined with pressure water injection in which a vibro hammer is used as a pile driver and pressure water injection is used in combination to reinforce the driving capability.

[0002]

2. Description of the Related Art Driving piles for steel pipe piles and steel sheet piles include:
It mainly includes the impact method, vibration method and embedded pile method. In the hammering method and the vibration method, the pile is forcibly penetrated by hitting or vibrating up to a predetermined supporting layer, so that it is possible to expect a supporting force commensurate with the ground strength.
Noise pollution is a problem.

[0003] The embedded pile method has the advantage that there is little pollution such as vibration and noise, but it has difficulties in the construction of large diameter and long piles, and uses a three-point support type pile driver as a base machine. Work safety may be lacking.

Therefore, a combined construction method combining a vibro hammer and pressure water injection has been proposed. As the pressure water injection device, a water jet cutter used for excavation of the ground is used. The continuous jet water jet discharged from the water jet cutter exerts an auxiliary effect of effectively cutting the target ground at the time of pile driving, thereby preventing generation of vibration.

[0005] FIG. 1 shows a water discharge port 11 of a water jet cutter 10 in a vibration driving pile method combined with pressure water injection.
To the injection nozzle 15 at the tip of the steel pipe pile 12,
It is a figure which shows the example which attached the piping material 16 which introduces pressure water. A vibro hammer is attached to the head of the steel pipe pile 12.

FIG. 2 is a diagram schematically showing the principle of this combined construction method. Nozzle 15 attached to the tip of driving pile 12 with pressure water discharged from the water jet cutter body
, And combined with the vertical vibration of a vibro hammer to drive a pile. The ground cutting effect provided by the water jet varies depending on the soil properties, but is extremely large.

[0007] The difference in the effect due to the soil properties of the target ground will be briefly described. In the case of hard sandy soil or cohesive soil, the cross section of the tip of the pile is cut to an extremely limited range by pressure water injection, and the soil is vibrated by a vibro hammer. Encourages movement and shearing of particles.
In addition, in compacted soil, bedrock, deep mixed improved soil, etc., a small gap is forcibly provided just below the nozzle, and stress concentration is attempted there to improve the crushing effect at the cross section of the pile tip due to vibro vibration energy. . Furthermore, in the cobble-stone-bearing gravel layer, the sandy soil surrounding the cobblestone is cut, the soil particles are liquefied, and the cobblestone in the cross section of the pile tip is forcibly moved and eliminated by vibrating vibration.

[0008] The soil particles in the initial sedimentation state undergo a liquefaction process and become compacted during re-deposition, ensuring ground recovery after construction and at the same time ensuring a greater bearing capacity than other construction methods. You.

In the vibratory driving pile method combined with pressure water injection, the driving speed, that is, the penetration speed of the pile is much higher in most of the ground compared with the hitting method, the vibration method using only the vibratory hammer, or the embedded pile method.

The features of the vibration driven pile method combined with pressure water injection are summarized as follows. 1) Extremely wide application range. 2) Construction using a crane is possible 3) Easy correction of pile accuracy 4) Construction without buckling is possible 5) Good workability and economy 6) Construction under special conditions is possible

[0011]

As described above, the vibration driving pile method combined with pressure water injection is an extremely excellent pile driving method. However, there is a problem in using the pressure water injection as an auxiliary for pile driving. Have been. It is a problem that arises from concerns about the effect of the pressure water injected into the ground on the ground surrounding the pile.

Usually, when driving a pile, a design calculation for calculating a bearing force generated by the pile is performed based on various design methods.

Here, the supporting force of the driving pile will be briefly described with reference to FIG. The driving force of the driving pile 12 is constituted by a front-end supporting force 20 and a peripheral friction force 21. The tip support force 20 is generated by a reaction force from the ground (support layer) to the load transmitted to the pile tip 14. The peripheral frictional force 21 is generated by the frictional force between the pile peripheral surface and the soil.

[0014] The conventional design method is for estimating the tip support force and the peripheral friction force determined by the pile and the ground, and the calculation method for obtaining these is also adopted as an official standard. For example, please refer to the road bridge specification book and its commentary.

[0015] However, in the case of the construction method using both pressurized water injection, since the construction management method has not been established, the ground water is often disturbed, that is, affected by the pressure water during construction. Therefore, it is difficult to calculate the design bearing capacity, and no confirmation method has been established to confirm that the bearing capacity has been secured.

Overlooking this situation, the present method is applied only to walls and temporary support piles that do not require a supporting force, so that the method of the present method is not sufficiently exhibited, and thus the field is not used in this field. Think big loss.

In view of the above situation, the present invention relates to a vibration driving pile method combined with pressure water injection in a pile driving method,
An object of the present invention is to manage a construction while taking into consideration the influence on the ground during the construction, so that a predetermined supporting force can be reliably obtained after the construction. It is another object of the present invention to realize this especially for a support pile. Specifically, in order to express the required tip support force and peripheral frictional force of the pile, in the pile driving process, the amount and pressure of the pressurized water are optimally controlled and adjusted based on the output of the vibro hammer. It is an object of the present invention to provide a pressure driven water injection combined vibration driving pile method having a construction management method to be adjusted.

[0018]

To achieve the above object, the present invention provides the following arrangement. (1) The vibration driving pile method combined with pressure water injection according to the present invention drives a driving pile into a target ground by combining vibration energy by a vibratory hammer and pressure water injection energy by a water jet, and drives the driving pile of the driving pile. The purpose of the present invention is to develop the tip support force at the tip and the peripheral frictional force at the pile peripheral surface. The driving pile is driven into the target ground from the ground surface, and after the pile tip reaches the support layer, is further driven until the pile tip reaches a predetermined stop depth in the support layer. Here, the area from the ground surface to the upper surface of the support layer in the target ground is referred to as “implantation layer”, and the area from the upper surface of the support layer to the depth of impact is referred to as “impact layer”. In this method, in the driving layer, the vibration energy by the vibro-hammer is detected, and the construction management of adjusting the pressure water injection energy so as to maintain the detected vibration energy within a predetermined range is performed. The present invention is characterized in that vibration management by vibratory hammer is maintained within a predetermined range and construction management for controlling pressure water injection energy is performed.

(2) The vibration energy of the vibro-hammer is evaluated using the current value of the vibro-hammer as an index, and the pressure water injection energy is evaluated using the pressure and the amount of water as indices. The current value of the vibro-hammer is maintained, and the pressure and amount of the pressurized water are adjusted or controlled.

(3) Preferably, in the striking layer, the pressure and the amount of the pressurized water are controlled so that the current value of the vibro-hammer is kept within a predetermined range not less than its rated value. More preferably, the striking layer is divided into an upper layer and a lower layer, and in the upper layer, the current value of the vibrohammer is maintained within a predetermined range equal to or higher than its rated value, and in the lower layer, the current value is higher than the rated value. Is kept within a predetermined range. For example, in the upper layer, the current value of the vibro-hammer is kept within a range from its rated value to 125% of the rated value, and in the lower layer, the current value is kept within a range from 125% of its rated value to its limit value. .

(4) Preferably, the pressure and the amount of the pressurized water are adjusted so that the current value of the vibratory hammer is kept within a predetermined range equal to or less than the rated value in the driving layer. For example, the current value of the vibro-hammer is maintained within a range from 60% of its rated value to its rated value.

(5) However, in the implanted layer, N ≧ 50
If there is an intermediate layer or an intermediate layer made of hard soil or gravel soil, the predetermined range for holding the output current value of the vibrohammer is preferably within a range exceeding its rated value and up to its limit value. .

(6) The bearing capacity of the driven pile driven under the above construction management method is calculated as follows. _{R u = q d A + UΣl} i f i R u: ultimate bearing capacity of the determined driving piles from ground (kN) A: pile tip cross-sectional area ^(m 2) _{q d:} ultimate bearing per unit area is supported by the pile tip Strength (kN / m ² ) U: Perimeter of driving pile (m) l _i : Layer thickness of layer region expressing peripheral friction force (m) f _i : Maximum circumference of layer region expressing peripheral surface friction force Surface friction force (kN / m ² ) In the above equation, the tip support force q _d (kN / m ² ) is represented by αN, and α is obtained by the ratio of the pile diameter of the driving pile to the thickness of the striking layer. The value is 300 at the maximum. The N value at that time is used as a maximum of 40. In the above equation, the peripheral frictional force fi (kN / m ² ) is 2N (kN / m ² ) and 100 kN / m ² or less for sandy soil, and 0.8 c (kN / m ² ) for viscous soil.
/ m ² ) or 8N (kN / m ² ) and 100 kN / m ² or less.

(7) Preferably, the fluctuation of the driving speed is measured and monitored during the driving process in order to detect that the tip of the driving pile has reached the upper surface of the support layer, that is, the upper surface of the driving layer. Further, in the striking layer, it is necessary to keep the current value of the vibratory hammer high. Therefore, it is preferable to load the driving pile with the entire mass of the vibratory hammer. Furthermore, preferably, a pipe member for guiding the pressure water to perform the pressure water injection is attached to the outer peripheral surface of the driving pile and is mounted to inject the pressure water in the axial direction of the driving pile.

[0025]

In the vibration driving pile method combined with pressure water injection according to the present invention, the driving layer detects vibration energy by vibratory hammer and adjusts the pressure water injection energy to keep the detected vibration energy within a predetermined range. In the striking layer, and in the striking layer, by maintaining the vibration energy by the vibro hammer within a predetermined range and controlling the pressure water injection energy, the pile tip of the driven pile after the completion of construction , A predetermined tip bearing force is generated, and a predetermined peripheral friction force is generated on the pile peripheral surface (that is, the entire driving layer and the striking layer).

[0026]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 4 is a diagram illustrating an example of a construction procedure of a pressure driven water injection combined vibration driven pile construction method (hereinafter, may be referred to as a “combined construction method”) managed by the present invention. The example of FIG. 4 is a standard construction procedure by crane construction.

First, at the planning stage prior to construction, a model of construction equipment and a pile are selected. For example, a vibratory hammer standard and a water jet cutter standard that are optimal for the ground to be driven are selected, and the number of holes for the water jet injection nozzle, the shape of the piping material, the mounting position, and the like are determined. In the combined construction method managed by the present invention, the state of bearing capacity of the driven pile is related to the ground condition, the specification of the pile, and the driving state of the pile (driving length, penetration speed). The driving situation is related to the standard of the used vibro hammer and the standard of the water jet cutter. Therefore, it is important to select a model that meets these conditions in order to develop a bearing capacity.

In the step shown in FIG.
6 is welded to a driving pile 12 such as a steel pipe pile. In the case shown, a plurality of injection nozzles 15 are provided at the tip of the pipe member 16, and the pipe member 16 is welded to the outer surface of the driving pile 12. The direction of the injection nozzle 15 is the axial direction of the driving pile 12. When the pipe member 16 is welded and attached, it is a buried type, that is, a system in which the pipe member is not diverted, but it is noted that the present invention is also applicable to a system in which the pipe member is temporarily fixed. Further, the pipe member 16 is preferably attached to the outer peripheral surface of the driving pile 12 (this will be described later).
However, application of the present invention to the case where the pipe member 16 is attached to the inner peripheral surface of the driving pile 12 is not excluded. Still further, a pile to which the present invention is applied is a steel pipe pile or a steel pipe sheet pile.

In the step, the high pressure hose 32 is connected to the piping material, and the driving pile 12 is suspended by the crane 33.

In a step, the driving pile 12 is erected at the driving position, and a water jet cutter (not shown) is started. Thereby, the pressurized water can be supplied to the high-pressure hose 32.

Further, in a step, the driving pile 12 is chucked by the vibro hammer 34. afterwards,
After performing normal adjustment such as centering of the driving pile 12, the vibro hammer 34 is started.

Then, in the step, the driving of the driving pile 12 is executed while applying the construction management method according to the present invention. This step will be described later in detail. Then, when the driving is performed to the stopping depth of 50, the driving is stopped.

After the driving is completed, the water jet cutter is stopped, and in a step, the vibrohammer 34 and the high-pressure hose 32 are removed, and the work is completed.

Next, with reference to FIG. 5, a construction management method in the driving step of the step of FIG. 4 will be described in detail. One of the features of the construction management method according to the present invention is that while the pile driving is in progress, the water energy by the water jet cutter and the vibration energy by the vibratory hammer are mutually adjusted and controlled.

Conventionally, it has been recognized that the influence on the ground must be taken into account when performing the combined construction method. However, during pile driving, the amount and pressure of the pressurized water are set to predetermined values. The aim was to reduce the output of the vibro hammer as much as possible and to try to complete the driving in as short a time as possible due to the effect of the pressure water.

FIG. 5 is a table summarizing one embodiment of the construction management method in the pile driving process according to the present invention.
In this construction management method, the ground layer from the ground surface of the target ground to the percussion depth is roughly divided into two layer regions, and finely divided into three layer regions. For each layer region, vibration energy and water jet by vibratory hammer are used. It regulates the water energy adjustment control method by the cutter. When it is roughly divided into two layer regions, the implanted layer from the ground surface to the upper surface of the support layer (layer A in the table of FIG. 5)
And the striking layer from the upper surface of the support layer to the striking depth (Fig. 5
In the table (1), the layer B is combined with the layer C). When divided into three layer regions, the striking layer is further divided into an upper layer and a lower layer (the striking layer (1) in the table in FIG. 5 is the upper layer, and the striking layer (2) is the lower layer). Here, the "strike depth" is the depth reached by the tip of the driving pile after the driving is completed.

In the example shown in the table of FIG. 5, when the diameter of the driving pile is D, the support layer is constructed so that the upper surface of the support layer is located 5D before the hitting depth. Also, the boundary between the upper layer and the lower layer of the hitting layer is constructed so as to be located 1D before the hitting depth. In addition, the thickness of the hitting layer is also referred to as “depth of penetration into the support layer”.

When the construction management according to the present invention is executed, the vibration energy by the vibro-hammer is sequentially measured by any of the indexes and detected. In the embodiments described below, the vibration energy of the vibratory hammer is determined using the current value of the vibratory hammer as an index, and the water energy of the water jet cutter is determined using the pressure of the pressured water to be discharged as an index.

A. Example of construction management in driving layer The driving layer, which is the first layer region, is a layer region from the ground surface to the upper surface of the support layer. In this layer, the pressure of the pressurized water discharged from the water jet cutter is adjusted so that the output current value of the vibrohammer exceeds 60% of the rated current value of the vibrohammer and falls within the range of the rated current value or less. The maximum pressure of the pressure water is 14.7 MPa. However, when there is an intermediate layer (N ≧ 50) or an intermediate layer such as hard soil or gravel, the output current value of the vibrohammer is allowed to exceed the limit value, that is, about 1.5 times exceeding the rated current value.
Reading the load fluctuation of the vibratory hammer output during the driving process is a basis for grasping the specific bearing force of the driving pile.

Normally, the output of the vibro-hammer fluctuates depending on the hardness of the ground, that is, the load on the vibro-hammer.
For example, when the load on the vibratory hammer increases due to the hard ground and the current value is likely to increase beyond this range, the pressure of the pressurized water is increased to increase the ground cutting effect.
As a result, the load on the vibro-hammer is reduced, and the current value is reduced. Further, when the ground is soft and the current value of the vibro hammer is likely to fall below this range, the ground cutting effect is weakened by lowering the pressure of the pressurized water. As a result, the load on the vibro-hammer increases, and the current value of the vibro-hammer increases.

B. Example of construction management in the striking layer (1) The striking layer (1), which is the second layer region, is the upper layer of the striking layer. Usually, the sand layer has N ≧ 30 and the cohesive soil layer has N ≧ 20. 3 shows a support layer. That is, it is a layer region from the upper surface of the support layer to the boundary with the lower layer of the striking layer. When reaching this region, the current value of the vibratory hammer is maintained so as to be equal to or higher than the rated current value, while the pressure of the pressurized water from the water jet cutter is controlled to 4.9 MPa or less. During the driving of the pile in this layer, the lifting of the crane lifting device is released so that the full mass of the vibrohammer is applied to the pile so that a predetermined current value is obtained.

C. Example of execution management in the hitting layer (2) The hitting layer (2), which is a third layer region, is below the hitting layer and is included in the support layer as is the upper layer of the hitting layer. That is, it is a layer region from the boundary with the upper layer of the hitting layer to the hitting depth. Also in this region, the pressure water injection is kept controlled. Then, the output current value of the vibro hammer is equal to or more than “rated current value * 1.25”, that is, 125% of the rated current value.
It holds so that it becomes above. However, in this case, when the current value exceeds the “rated current value * 1.5”, that is, the limit value, it is preferable that the duration does not exceed 5 minutes. This is to avoid burning of the motor of the vibro-hammer. During the driving of the pile in this layer, the lifting of the crane lifting device is released so that the full mass of the vibrohammer is applied to the pile so that a predetermined current value is obtained.

It should be noted here that the construction management method shown in FIG. 5 is an example, and the current value of the vibro-hammer, the specific setting of the pressure of the pressurized water, and other conditions may be changed depending on the ground condition. .

The basic aspect of the construction management method according to the present invention is as follows. In the driving layer, a change in the load on the vibratory hammer is monitored and detected, and the load on the vibratory hammer is maintained within a predetermined range. In addition, the ability to cut ground by pressurized water is adjusted. Thereby, the expression of the peripheral frictional force in the pile supporting force is ensured. The peripheral friction force is related to the penetration speed at the time of pile driving. Therefore, by adjusting the vibration energy by the vibro-hammer and the water energy by the water jet cutter for each target ground where the pile is to be driven in accordance with the construction management procedure as shown in FIG. 5, it is possible to expect the resistance of the ground around the pile peripheral surface. it can.

In the striking layer, when the tip of the pile penetrates into the support layer, in order to prevent the turbulence and destruction of the ground of the support layer, the driving means of the pile is set to be smaller than the water energy of the water jet cutter. By controlling the water energy of the water jet cutter so as to depend on the vibration energy of the vibratory hammer, it is expected that the resistance of the ground equal to the closed cross-sectional area of the tip at the time of pile driving will be obtained.

In carrying out the construction management method as described above, it is preferable to continuously measure and record the following items in order to comprehensively monitor the construction situation during driving. The specific measuring method is an example. 1) Pile penetration depth Confirmation of pile penetration depth shall be the same as the conventional impact method, for example. 2) Pile driving speed or driving time The driving speed is measured and recorded at every 1 m of driving depth. Also, it is desirable to record every 10 cm for the 50 cm of the final hit. For the measurement at the time of hitting, it is necessary to previously mark the length of the stake to be measured (10 to 50 cm) on the stake to be measured and to drive the stake. By reading the variation of the driving speed, it is possible to determine the difference from the ground surveyed beforehand and the determination of the penetration into the support layer. 3) Vibro hammer motor output (calculated from current value and voltage value) To obtain the vibro hammer motor output, measure the current and voltage during operation and substitute them into the output formula. Measure and record every 1 m of the pile depth from the ammeter and voltmeter provided.
In addition, it is desirable to record every 10 cm for 50 cm of the final striking of the pile, and read and record the maximum current value and the minimum voltage value of each. This is a material for more specifically grasping the bearing capacity by knowing the tendency of the load fluctuation on the pile. 4) Change in pile amplitude Attach an amplitude meter to the side of the pile and read it during driving, or attach a blank sheet and draw a horizontal line with a writing instrument during driving.
The movement of the stake is recorded and one half of the total amplitude is recorded as the amplitude. The measurement of the amplitude serves as one of the criteria for determining whether or not the performance of the vibratory hammer is appropriate, and can determine whether the vibratory hammer is embedded in the support layer. 5) Pressure and volume of pressurized water by water jet cutter The pressure is measured and recorded by a pressure gauge at every 1 m of pile depth. By controlling and adjusting the pressure and amount of the pressurized water, the vibration energy of the vibro-hammer can be adjusted so as to maintain the vibration energy within a predetermined range for each of the layers in each region, thereby ensuring that the vibratory hammer is firmly embedded in the support layer and has a sufficient support force. (Tip support force and peripheral surface frictional force).

As a result of performing the construction by the vibration driving pile method combined with the pressure water injection characterized by the construction management method according to the present invention as described above, the ultimate support of the pile was obtained by the supporting force estimation formula summarized in the table of FIG. It was empirically confirmed that the force could be calculated. The basic formula is as follows. _{R u = q d A + UΣl} i f i R u: ultimate bearing capacity of the determined driving piles from ground (kN) A: pile tip cross-sectional area ^(m 2) _{q d:} ultimate bearing per unit area is supported by the pile tip Strength (kN / m ² ) U: Perimeter of driving pile (m) l _i : Layer thickness of layer region expressing peripheral friction force (m) f _i : Maximum circumference of layer region expressing peripheral surface friction force Surface friction force (kN / m ² )

The ultimate bearing capacity of q _d per unit area is supported by piles tip is as the middle graph in the table of FIG.
Note that the vertical axis is a value obtained by dividing _qd by the N value, and the horizontal axis is a converted value obtained by dividing the depth of the support layer by the pile diameter D. Further, the peripheral surface frictional force of f _i is the value depending on the type of soil as the lower part of Table of Figure 6 differs. c is the adhesive strength of the ground.

In the above equation, the tip supporting force q _d (kN /
m ² ) is represented by αN, and α is obtained by the ratio between the pile diameter of the driving pile and the thickness of the striking layer.
The N value at that time is used as a maximum of 40. In the above equation, the peripheral frictional force fi (kN / m ² ) is 2N (kN / m ² ) and 100 kN / m ² or less for sandy soil, and 0.8 c (kN / m ² ) for viscous soil. / m ² ) or 8N (kN / m ² ) and 100 kN / m ² or less.

In the method of the present invention, a preferred example of a method of attaching a pipe material to a driving pile will be described. It is preferable that a pipe member for guiding the pressurized water from the water jet cutter be mounted on the outer peripheral surface of the driving pile. The reason is that when installed on the inner peripheral surface, the soil inside the pile tip at the support layer is extremely discharged, the ground facing the cross section of the pile tip is crushed, and the blockage of the tip is blocked. This is because there is a possibility that it cannot be obtained. As described above, the tip supporting force of the pile is obtained by the resistance from the ground to the closed cross section of the tip of the pile. In addition, in order to obtain the effect of the pressurized water injection most efficiently, it is preferable that the piping direction of the piping material in the support layer is the driving direction of the driving pile.

[0051]

According to the present invention, a vibration driving pile method combined with pressure water injection which has a construction management method capable of reliably developing a predetermined tip supporting force and a peripheral friction force of a driving pile is established. That is, in the striking layer, the energy of the pressure water is controlled and vibration energy is kept at a high value in order to avoid excessive ground crushing, and in the striking layer, the vibration energy by the vibratory hammer is kept within a predetermined range. Adjust the pressure water energy as needed. Further, the present invention has presented a bearing capacity estimation formula applicable to a driven pile constructed under the construction management method.

When the combined construction method is applied under the construction management according to the present invention, the construction can be completed while controlling the influence on the ground. The predetermined supporting force can be surely developed by the driving and the reliable embedding into the support layer.

As described above, if the combined construction method is applied under the construction management according to the present invention, the steel pipe pile and the steel pipe sheet pile can be widely used as a highly reliable support pile.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example in which a pressure water guide pipe material is attached to a steel pipe pile in a vibration driving pile method combined with pressure water injection.

FIG. 2 is a diagram schematically showing the principle and construction of a vibration driving pile method combined with pressure water injection.

FIG. 3 is a diagram showing a mechanism of a supporting force of a pile driven by a pile driving method.

FIG. 4 is a diagram showing an example of a construction procedure of a vibration driving pile method combined with pressure water injection managed by the present invention.

FIG. 5 is a table showing an example of a construction management method in a pile driving process according to the present invention.

FIG. 6 is a table showing an equation for estimating the bearing capacity of a pile driven by the vibration driven pile method combined with pressure water injection having the construction management method according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Water jet cutter 11 Water outlet 12 Driving pile 14 Pile tip 15 Pressure water injection nozzle 16 Piping material 20 Tip support force 21 Friction force 32 High pressure hose 33 Crane 34 Vibro hammer

 ────────────────────────────────────────────────── ─── Continued on front page (72) Inventor Yoshihide Suzuki 7-10-4 Nishigotanda, Shinagawa-ku, Tokyo F-term in Tomec Co., Ltd. (reference) 2D050 AA08 CB32 CB42 FF02 FF03

Claims (18)

[Claims] 1. A method of vibrating a pile driven into a target ground by combining a vibration energy by a vibratory hammer and a pressure water injection energy by a water jet, wherein the target ground is moved from the ground surface to the upper surface of a support layer. When the driving pile includes a driving layer up to and a driving layer from the upper surface of the supporting layer to the driving depth, the driving force of the driving pile expresses a tip supporting force at a pile tip and a peripheral frictional force at a pile peripheral surface. The driving layer detects vibration energy by the vibratory hammer, adjusts the pressure water injection energy to maintain the detected vibration energy within a predetermined range, and controls the vibratory hammer in the striking layer. For controlling the pressure water injection energy while maintaining the vibration energy by the pressure within a predetermined range Pressure water injection combined vibration driving Pile characterized physical methods. 2. A method of combining a vibration energy from a vibratory hammer with a pressure water injection energy from a water jet to drive a driving pile into a target ground, wherein the target ground is struck from above a support layer. In the case of including a striking layer up to a depth, vibration by the vibratory hammer at the striking layer is used to develop a tip support force at a pile tip of the driven pile and a peripheral frictional force at a pile peripheral surface. A vibration driving pile method combined with pressure water injection, characterized by a construction management method for maintaining the energy within a predetermined range and controlling the pressure water injection energy. 3. A method of combining a vibration energy by a vibratory hammer with a pressure water injection energy by a water jet to drive a driving pile into a target ground, wherein the target ground is moved from the ground surface to an upper surface of a support layer. In the case of including the driving layer up to, in order to express the peripheral friction force on the pile peripheral surface of the driven pile, the vibration energy by the vibratory hammer is detected in the driving layer, and the detected vibration energy is A construction method for controlling the pressure water injection energy to maintain the pressure water injection energy within a predetermined range. 4. A method of driving a driven pile into a target ground by combining vibration energy by a vibratory hammer and pressure water injection energy by a water jet, wherein the target ground is moved from the ground surface to the upper surface of a support layer. When the driving pile includes a driving layer up to and a driving layer from the upper surface of the supporting layer to the driving depth, the driving force of the driving pile expresses a tip supporting force at a pile tip and a peripheral frictional force at a pile peripheral surface. To detect the current value of the vibro-hammer in the driving layer, adjust the pressure and amount of the pressure water to maintain the detected current value within a predetermined range, and in the driving layer The pressure water injection is characterized by a construction management method for maintaining the current value of the vibratory hammer within a predetermined range and controlling the pressure and amount of the pressure water. Vibration driving Pile. 5. A method for driving a driven pile into a target ground by combining a vibration energy from a vibratory hammer and a pressure water injection energy from a water jet, wherein the target ground is struck from above a support layer. In the case of including a striking layer up to a depth, in order to develop a tip support force at a pile tip of the driven pile and a peripheral frictional force at a pile peripheral surface, a current of the vibratory hammer is measured at the striking layer. A vibration driving pile method combined with pressure water injection, characterized by a construction management method for controlling the pressure and the amount of the pressure water while maintaining the value within a predetermined range. 6. A method of driving a pile driven into a target ground by combining a vibration energy by a vibratory hammer and a pressure water injection energy by a water jet. In the case of including the driving layer up to, in order to express the peripheral frictional force on the pile peripheral surface of the driven pile, the current value of the vibro hammer is detected in the driving layer, and the detected current value is calculated. A construction method for controlling the pressure and amount of the pressurized water so as to maintain it within a predetermined range. 7. The construction management method according to claim 4, wherein a predetermined range in which the current value of the vibratory hammer is held in the hitting layer is within a predetermined range that is equal to or greater than a rated value. Vibratory driving pile method combined with pressure water injection. 8. The predetermined range in which the current value of the vibratory hammer is held in the striking layer is within a predetermined range equal to or higher than a rated value of an upper layer of the striking layer. The method of claim 4 or 5, wherein the lower layer is a construction management method in which the lower layer is within a predetermined range of a value higher than the rated value. 9. The predetermined range in which the current value of the vibratory hammer is held in the striking layer is in a range from a rated value to 125% of the rated value in an upper layer of the striking layer. The method according to claim 4 or 5, wherein the lower layer of the striking layer has a construction management method in a range from 125% of its rated value to its limit value. 10. The construction management method according to claim 4, wherein a predetermined range in which the driving layer holds a current value of the vibrohammer detected is within a predetermined range equal to or less than its rated value. Vibration driving pile method combined with pressure water injection described in 4. 11. A construction management method in which a predetermined range in which the current value of the vibratory hammer detected by the driving layer is held is within a range from 60% of its rated value to its rated value. The vibration driving pile method combined with pressure water injection according to claim 4 or 6. 12. When the implanted layer has an intermediate layer of N ≧ 50 or an intermediate layer made of hard soil or gravel, the predetermined range for holding the current value of the vibrohammer exceeds the rated value. The method of claim 4 or 6, wherein the construction is controlled within a range up to the limit value. Wherein said tip supporting force of use in the method of calculating the tip bearing capacity q _{d (kN} / m ²⁾ are indicated by alpha N, alpha is the ratio of the thickness of the Uchidome layer and pile diameter of the driving pile The method according to any one of claims 1 to 12, wherein the maximum value is 300 and the maximum N value is 40. 14. When the target ground is sandy soil, the peripheral surface frictional force fi (kN / m) used in the method of calculating the peripheral surface frictional force.
The ^{2), 2N (kN / m} 2) and 100 kN / m ² or less pressure water injection combined vibration driving Pile as claimed in any one of claims 1 to 12, characterized in that. 15. When the target ground is a cohesive soil, the peripheral surface frictional force fi (kN / m) used in the method of calculating the peripheral surface frictional force.
² ) is set to 0.8 c (kN / m ² ) or 8 N (kN / m ² ) and 100 kN / m ² or less.
13. The method of vibration driving pile combined with pressure water injection according to any one of 12 above. 16. The construction management method according to claim 1, further comprising measuring a change in driving speed of the driving pile to detect that a tip end of the driving pile has reached the striking layer. The vibration driven pile method combined with pressure water injection according to any one of the above. 17. The vibration combined with pressure water injection according to claim 7, wherein a construction management method of loading the entire mass of the vibratory hammer on the driving pile at the striking layer. Driving pile method. 18. A pipe member for guiding pressure water to perform the pressure water injection is attached to an outer peripheral surface of the driving pile,
The method of claim 1, wherein the driving pile is mounted to inject the pressure water in an axial direction of the driving pile.