JPH0215698B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides foundation pile construction in which the relationship between the construction method and the construction ground can be quickly and reliably determined in order to construct foundation piles on the most suitable ground in ideal conditions. Regarding management methods.

Normally, when constructing foundation piles using an earth auger or the like without noise or vibration, in order to obtain a reliable bearing capacity of the foundation pile, it is necessary to check the penetration of the foundation pile into the supporting ground and the driving approach conditions. Each pile must be accurately measured and managed. As a method,
Conventionally, the determination method has been completely primitive, based on pre-examined boring charts and the quality of the soil discharged to the ground, so it has been difficult to ensure that the foundation pile reaches the supporting layer. It is of course difficult to determine whether each foundation pile is embedded, and the number of boring surveys mentioned above is limited by the construction ground, so it is completely impossible to determine the bearing capacity of each foundation pile. Ta.

The applicant of the present application first installed a load sensing device and a displacement sensing device on a part of the auger that drills into the ground and presses in the pile body, and records changes in load and displacement of the pile during driving, Developed and applied for a device that can determine the relationship between piles and the ground (Patent application 1986-53895)
However, in the device based on this patent application, changes in load (power,
I tried to record the displacement of the pile (electric power consumption) and the displacement of the pile to obtain a correlation between the displacement of the pile, that is, the depth of pile insertion and the change in load, but the length of the recording paper required to press the unit length of the pile was the unit. Each length has different drawbacks,
Particularly when the displacement of the pile is small, the disadvantage is that only the recording paper becomes long, so even if changes in load, especially electric energy, are recorded, the displacement of the unit length of the pile, that is, the comparison at each depth, cannot be determined. Therefore, there was a drawback that it was impossible to compare and confirm with the boring survey sheet conducted in advance.

Therefore, as a result of various experimental studies using the above-mentioned device, we found that, as shown in the following formula, F=f(N) N=f'(W, E, H) becomes a function of
Furthermore, it was found that the ground hardness N is a function of the instantaneous power W, time H, and energy E required to drill a hole in the ground and press in a foundation pile. The instantaneous power W, time H, and energy E can be recorded on a recording paper representing the press-in depth, that is, on a recording paper on which the press-in and displacement of the pile are graduated on a fixed scale (as a result, the scale represents the press-in depth). It is desirable for management of foundation pile construction, and in particular, it is best to record energy E in the form of a bar graph for each press-in depth of the unit length of the pile, which is also optimal for determining the penetration status of the foundation pile into the supporting ground and the bearing capacity F. It has been found.

Based on the above, the present invention aims to provide a foundation pile construction management method characterized by recording instantaneous power W, time H, and energy E on a recording paper that moves in synchronization with the pile press-in speed. This invention was developed to accurately determine the penetration state of the pile into the supporting layer and the pile supporting capacity based on the correlation between the press-in depth and the recorded value.

Embodiments of the present invention will be described below with reference to the drawings.

1 is a pile driver, 2 is a drive unit, 3 is an auger, and 4 is a displacement meter, which is connected to a part of the drive unit 2 while maintaining a constant tension on a wire 5. Further, a power converter 6 for sensing load power is provided in a part of the drive unit 2, and is connected by wiring to an integration counter 7 and a recorder 8 so as to be energized. The displacement meter 4 has several tension pulleys 9 ₁ , 9 ₂ , 9 as shown in FIG.
₃ , is composed of a pulse oscillator 10, a winding drum 11, and a torque motor 12, and the torque motor 12 applies a constant load to the winding drum 11 through a belt 13 so that the wire 5 is always in tension.
A belt 14 is stretched between the tension pulley 9 ₁ and the pulse oscillator 10, and the movement of the wire 5 can be read by the tension pulley 9 ₁ .
In other words, the pulse oscillator 10 is configured to convert only the downward motion of the vertical motion of the drive unit 2 and the pile P into an electrical signal, and the recorder is electrically connected via the integration counter 7 and the paper feed tuner 15. Only the signal of the downward movement of the pile No. 8 is transmitted. The paper feed tuner 15 receives an electrical signal generated in response to the downward movement of the pile P, and synchronizes the paper feed speed of the recorder 8 with the downward movement (displacement amount) of the pile P, thereby adjusting the upward movement of the pile. The configuration is such that paper feeding is stopped when this occurs. The integration counter 7 is configured to integrate the power signal sent from the power converter 6 and transmit the integrated power, that is, the energy E, to the recorder 8. Dynamic displacement is 50cm
Perform the above integration until reaching the unit amount such as ~100cm,
When the unit amount is reached, the integrated value _E1 is canceled, reset to 0, and integrated again, and the recorder 8 is used to record the previous integrated value _E1 as is until the displacement amount reaches the next unit amount. It is configured to transmit the subsequent integrated values of unit quantities E ₂ , E ₃ ...
It is also configured to record continuously. Therefore, as shown in Fig. 3, the energy E is applied to the downward movement of the pile P, that is, the unit of the pile, on the recording paper that is sent synchronously with the press-in, that is, on the record paper that represents the press-in depth of the pile that is graduated on a constant scale. The energy required to press fit the length is recorded in a bar graph, which also indicates the hardness of the ground at each depth.

Incidentally, the above-mentioned integration of the displacement of the pile is performed only for the downward movement of the pile, and the pulse oscillator is configured to send a signal to the integration counter so that the above-mentioned integration is not performed for the upward movement of the pile.

Furthermore, a time oscillator 16 is incorporated in the recorder 8, and the time oscillator 16 is configured to record the time H required for foundation pile press-in on a recording paper. , the energy required to press-fit a unit length of pile E ₁ , E ₂ ,
E ₃ ... and the required time H can be recorded at the same time. Further, in the figure, each number 17 is for converting a digital amount electrically transmitted by a D/A converter into an analog amount,
If this is not available, the digital amount will be printed directly onto recording paper.

The device used in the present invention has the configuration described above, and its operating state will be explained next.

First, the pile P is suspended together with the auger 3 below the drive section 2, and then when an electric current is applied to the drive section 2, the auger 3 rotates and the pile P is gradually inserted into the hole while drilling a hole in the ground. let it sink. In this case, an electrical signal is transmitted from the pulse oscillator 10 in the displacement meter 4 operated by the wire 5 connected to a part of the drive unit 2 to the recorder 8 via the paper feed tuner 15, and the Recording paper will also be sent. During this period, the power W required for rotational penetration of the auger 3 is transmitted to the recorder 8 via the power converter 6 and recorded on recording paper, and the power signal transmitted from the power converter 6 is transmitted to the unit length of the pile. Energy E ₁ , E ₂ , E _{3 .} . . required for press-fitting a unit length of the pile is accumulated in the integration counter 7 for each press-in depth, and is calculated by transmission from the pulse oscillator 10, and is recorded in a bar graph. Furthermore, the time oscillator 16, which was activated at the same time as the recorder 8, is activated to record the time H required to press in the pile, and as shown in Fig. 3, the instantaneous electric power W, The energy E ₁ , E ₂ , E _{3 .} . . and the time H required to press-fit the unit length of the pile are recorded at the same time. Therefore, by using this record, it is possible to manage the construction state at the depth of the pile press-in, and based on the correlation between the above-mentioned recorded values, it is possible to easily and reliably determine the state of penetration of the pile into the supporting layer and the pile supporting capacity.

As described above, the foundation pile construction management method according to the present invention records the instantaneous electric power W and the time H required for construction on a recording paper representing the press-in depth, and records the energy E ₁ required to press-in the unit length of the pile. , E ₂ ,
Since E ₃ ... is simultaneously recorded in a bar graph, the press-in condition of the driven pile column can be accurately known from beginning to end on the ground, and the ground resistance at the tip of the pile column can be determined according to the press-in depth of the foundation pile. can be grasped as time, power, and energy-related values at all times during construction, ensuring that the foundation piles are firmly embedded in the designated support layer, and that stable pile bearing capacity can be expected. . Another advantage is that it is possible to record and manage the pile press-in construction time using automatic construction time recording paper, and even if the ground is hard and it takes time to penetrate the piles, the recording paper does not become long. In particular, since the energy E ₁ , E ₂ , E ₃ ... is recorded in a bar graph, each bar represents the energy at each depth of pile press-in, and the recorded values in the bar graph indicate the magnitude of the energy at each depth, Furthermore, the strength and weakness of the ground can be clearly determined at a glance, and the recorded values can be compared and confirmed with the boring survey sheet conducted before construction, making it possible to install piles more reliably.

[Brief explanation of drawings]

FIG. 1 is an overall schematic diagram showing an embodiment of the present invention;
FIG. 2 is a block diagram of the main parts of the apparatus used in the present invention, and FIG. 3 is a chart showing the recording state according to the present invention. DESCRIPTION OF SYMBOLS 1... Pile driver, 2... Drive unit, 3... Auger, 4... Displacement meter, 5... Wire, 6... Power converter, 7... Integration counter, 8... Recorder,
10...Pulse oscillator, 15...Paper feed tuner,
16...Time oscillator, P...Pile, W...Electric power, E
...Energy, H...Time.

Claims (1)

[Claims] 1. When driving and press-fitting a pile, continuously record the time H and power W required to press-in the pile on a recording paper that moves in sync with the downward press-in of the pile and indicates the press-in depth in the direction of movement, and A foundation pile construction management method characterized by recording energy E1, E2, E3, etc. required for press-fitting a unit length of a pile in the form of a bar graph for each press-fit depth.