JPH07293192A - Measuring method for press-in quantity of buried pipe - Google Patents

Abstract

PURPOSE:To measure a distance accurately without being affected by underground water by measuring the press-in quantity of a buried pipe by means of a band plate, by a clamp fixing one end of the band plate on a buried pipe, a traction means which pulls the other end of the band plate at a starting shaft front section, and of a laser irradiation range finder. CONSTITUTION:A starting pit wall 7 preventing underground water and earth and sand from entering in, is set at the drive position of a buried pipe 11 at a front face within a starting shaft, and a hole larger than the outer diameter of the buried pipe 11 is bored at the center section of the starting pit wall 7. In this case, a water stop rubber 18 is installed in the hole section while being brought into contact with the outer circumference of the buried pipe 11. Furthermore, a push ring 8 is set at the rear end of the buried pipe 11, so that the propelling force of main thrust jacks 12 mounted on their rear section is thereby uniformly transmitted to the buried pipe 11. Beside, a bearing wall 13 is provided for the rear section of the main thrust jacks 12 for supporting the propelling force. Since the band plate 2 is moved forward by a traction means by the press-in quantity of the buried pipe 11 as the buried pipe is thrusted, the quantity of the movement of the band plate can thereby the measured by a range finder 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring a propulsion press-fitting distance on a starting shaft side in a method for detecting the position of a front conductor in a propulsion method, and more particularly to a method for detecting the press-fitting amount of a buried pipe in real time by a laser irradiation method.

[0002]

2. Description of the Related Art In the propulsion method, in order to lay a buried pipe according to a planned line, it is important to know the posture of the tip conductor at an early stage. If the correct attitude of the conductor is known at an early stage, it can be easily corrected in the correct direction according to the planned line. As a method of detecting the attitude of the leading conductor, a method of sequentially measuring from the base point in the starting shaft to the leading conductor at the tip with an optical instrument is generally used. In addition, when the propulsion section is a straight line and has a long distance, an optical device using a laser is used, and a method of irradiating the laser on a target installed in the front conductor and measuring a deviation from the reference line has been used.

However, in a propulsion method in which the propulsion section includes a curve, it is impossible to see from the starting shaft to the front conductor, and it is impossible to use the above-mentioned optical device using a laser. For this reason, a method is used to check the position of the lead conductor by performing a traverse survey up to the lead conductor measurement point using an optical device such as a transit, but the radius of the curve becomes smaller and the curve propulsion extension becomes longer. In such a case, the installation and replacement of the optical equipment must be frequently performed, and the time spent for surveying becomes very long, resulting in a significant decrease in other propulsion work time.

Therefore, in recent years, in order to solve the above problems, a method as disclosed in Japanese Patent Laid-Open No. 5-141186 has been developed. According to the present invention, a gyro compass or the like for detecting an azimuth is mounted in the leading conductor, and the azimuth angle of the leading conductor is continuously detected. Then, as a means to detect the distance from the gyro compass to the base point in the starting shaft in real time, the surface of the buried pipe is irradiated with laser light, and the movement of the light and dark mottled patterns is received by the image sensor to determine the press-fitting amount. A laser irradiation method for calculating is used. Therefore, it is possible to continuously detect the azimuth angle of the leading conductor and the press-fitting amount of the buried pipe, and it is possible to easily detect the position of the leading end conductor without interrupting the propulsion operation.

[0005]

With the above-mentioned conventional technique, the position of the tip conductor can be easily detected in real time even in curve propulsion, and the time spent for surveying work can be reduced and the construction period can be remarkably shortened. In addition, complicated and frequent surveys are not required, and the working environment can be improved.

However, in the above distance measurement by the laser irradiation method, when the laying position of the buried pipe is below the groundwater level, as shown in FIG. 4, the starting pit wall 7 in front of the starting pit is used.
From the position, groundwater 19 flows into the starting shaft along the surface of the buried pipe 11. The start pit wall 7 is provided with a waterproof rubber 18 for preventing backflow of groundwater 19,
It is difficult to completely stop the water in a place where the groundwater pressure is high or in long-distance propulsion due to abrasion of the rubber 18. Since the groundwater 19 flowing in the starting shaft travels backward along the surface of the buried pipe 11, the distance meter 1 by the laser irradiation method installed in the front part of the starting shaft detects the movement of the groundwater 19 and the buried pipe An error will occur in the amount of press-fitting.

Therefore, it becomes impossible to detect the distance from the gyro compass of the leading conductor to the base point in the starting shaft, and it becomes necessary to carry out actual measurement with a tape measure or the like, making it impossible to measure the position of the leading conductor in succession. At the same time, a large amount of time is spent to measure the distance, and the time required for the propulsion work is shortened, which leads to a delay in the construction period.

Therefore, in view of the above-mentioned problems of the prior art, the present invention provides a method capable of performing distance measurement in real time without being affected by groundwater even when it is propelled and buried under groundwater.

[0009]

That is, the structure of the present invention comprises a strip plate extending along the axial direction of the buried pipe, a stopper for fixing one end of the strip plate at the rear end of the buried pipe, and the other end of the strip plate. Is a method for measuring the amount of press-fitting of a buried pipe, which comprises a device for pulling the vehicle in front of the starting shaft and a range finder based on a laser irradiation system installed at a predetermined position on the strip.

As the range finder, a laser irradiation method is used in which the surface of the strip plate is irradiated with laser light, and the movement of light and dark mottled patterns is received by an image sensor to calculate the amount of press fit. As the strip plate, it is possible to use a cloth or steel plate having a dull surface, but it is effective to use a dull steel plate that is less stretched by traction.

As a method of fixing one end of the strip plate to the rear end of the buried pipe, a method of fixing it to a metal fitting attached to the outer peripheral portion of the push ring to be brought into contact with the rear end surface of the buried pipe is used. The other end of one of the strips is towed by a towing device provided on the starting pit wall or earth retaining wall so that the strip does not sag. As a method of pulling, by fixing the end of the strip to the tip of a coil spring provided in the storage box, a method of constantly generating a pulling force on the strip or a strip passed through a roller attached to the earth retaining wall A method in which a weight is fixed to the tip of the strip to generate a traction force on the strip is used.

[0012]

According to the buried pipe press-fitting amount measuring method of the present invention, the band plate is moved forward by the traction device by the amount of press-fitting of the buried pipe as the buried pipe is propelled, and the moving amount of the band plate is moved by the distance. It is measured by a meter. At this time, even if groundwater flows on the outer peripheral surface of the buried pipe, accurate measurement can be performed without being affected by groundwater.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a sectional view illustrating an embodiment of the present invention. A start pit wall 7 for preventing the inflow of groundwater and earth and sand is installed at the front of the buried pipe propulsion position in the start pit. A hole slightly larger than the outer diameter of the buried pipe 11 is penetrated through the center of the starting pit wall 7, and the buried pipe 11 is inserted in the hole.
The waterproof rubber 18 is attached so as to abut the outer circumference.
At the rear end of the buried pipe 11, a former push jack 1 equipped at the rear
A push ring 8 for evenly transmitting the propulsive force of 2 to the buried pipe 11.
Is installed. A pressure bearing wall 13 for supporting a propulsive force is provided behind the former push jack 12.

A thin strip 2 is provided extending in the axial direction with a distance of several to several tens from the buried pipe 11. One end of the strip 2 is
It is fixed by a stopper 8 of a push ring 10 provided at the rear end of the buried pipe 11. The other front end of the strip 2 is attached to a traction device A installed on the starting pit wall 7 and is always tensioned with a constant traction force so that the strip 2 does not sag. A distance meter 1 is installed at a predetermined position on the strip 2 so as to face the strip 2. The arm 9 of the rangefinder 1 is fixed to the earth retaining wall 14 in front of the starting shaft.

FIG. 2 is a sectional view for explaining the structure of the traction device A in detail. The other end of the strip plate 2 whose one end is fixed by the stopper 8 is taken into the storage box 3 from the guide 6 provided at the front of the storage box 3 and fixed to the coil spring 5 fixed to the central support shaft 4. Has been done. A slide fitting 15 is attached to the rear end of the storage box 3 so that the storage box 3 can move up and down. Fix the storage box 30 with the slide metal fitting 1
This is done by fixing 5 to the starting pit wall 7.

FIG. 3 is a sectional view for explaining another embodiment of the traction device A. The strip 2 whose one end is fixed to the stopper 8 is a roller 16 provided on the starting pit wall 7 and the earth stop wall 14.
The belt 2 is fixed to the weight 17, and the tension is always applied to the strip 2. The strip 2 to be used is made of cloth or steel having a dull surface, but is generally made of steel which is less stretched by traction. Further, the strip plate 2 is used as a relatively thin one because it is wound in a roll shape and passes through the roller portion.

Next, a method of measuring the press-fitting amount of the buried pipe by the above device will be described with reference to FIGS. 1 and 2. When the propulsion construction of one buried pipe 11 is completed, the next buried pipe 1
1 is connected to the rear. When the connection of the buried pipe 11 is completed, the push ring 10 is installed at the rear end of the buried pipe 11, and the end of the strip 2 is fixed to the stopper 8. When the setting of the strip 2 is completed, the original push jack 12 is extended and the embedded pipe 11 is press-fitted.

With the press-fitting of the buried pipe 11, the strip 2 is pulled toward the pulling equipment A by the same amount as the press-fitting amount of the buried pipe 11. The distance meter 1 measures the amount of movement of the strip 2. As a measurement method of the rangefinder 1, a laser irradiation method is used in which the surface of the strip plate 2 is irradiated with laser light, and the movement of the light and dark mottled patterns is received by an image sensor to calculate the amount of press fit.

The press-fitting amount of the buried pipe 11 obtained by the real-time distance meter 1 is input to the processing function together with the data of the attitude angle obtained by a gyrocompass or the like (not shown) mounted on the lead conductor and calculated by the computer. It is more effective to always display the difference from the planned value or display it in a graph.

[0020]

EFFECTS OF THE INVENTION According to the present invention, even if the distance measurement of the buried pipe is propulsion construction under the groundwater level, accurate and highly accurate distance measurement can be performed without the influence of groundwater on the strip.
Furthermore, by enabling highly accurate distance measurement without being affected by groundwater, it is no longer necessary to use excessive nerves to discharge groundwater from the starting pit wall, and the propulsion work environment has improved significantly.

[0019]

[Brief description of drawings]

FIG. 1 is a cross-sectional view illustrating an entire embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating in detail the traction device of the present invention.

FIG. 3 is a sectional view showing another embodiment of the traction device.

FIG. 4 is a cross-sectional view illustrating distance measurement according to a conventional technique.

[Explanation of symbols]

 A Traction device 1 Distance meter 2 Strip plate 3 Storage box 4 Support shaft 5 Coil spring 6 Guide 7 Start pit wall 8 Stopper 9 Arm 10 Pusher wheel 11 Buried pipe 12 Pusher jack 13 Bearing wall 14 Earth stop wall 15 Sliding bracket 16 Laura 17 Weight 18 Water-stop rubber 19 Groundwater

Claims (1)

[Claims] 1. A measuring method for calculating in real time the propulsion press-fit amount of a buried pipe in a starting shaft by a laser irradiation method, wherein a strip extending along the axial direction of the buried pipe and one end of the strip are buried. It consists of a stopper for fixing at the rear end of the pipe, a traction device for pulling the other end of the strip plate at the front of the starting shaft, and a distance meter by a laser irradiation system installed at a predetermined position on the strip plate. A characteristic method for measuring the amount of press-fitting of buried pipes.