JP7330308B2 - Pile foundation construction method and construction management system - Google Patents

Description

The present invention relates to a pile foundation construction method and a construction management system, and in particular, a construction method for rotating and penetrating a cylindrical member such as a steel pipe in a rotary pile construction method or a casing in an all-casing construction method into the ground with high accuracy, and the construction method. It relates to a construction management system.

For example, the rotary pile construction method, which is one of the pile foundation construction methods, is a method of rotating and penetrating a steel pipe pile having blades at the tip into the ground. As rotary pile construction methods, there are known a pile head rotation method in which a rotational force is applied to the pile head, and a body rotation method in which an excavator applies a rotational force to the pile body. In particular, the body rotation method is applied to construction of steel pipe piles with a relatively large diameter (for example, "500 mm or more"). Here, the pile construction accuracy in the pile workmanship control standard of the Ministry of Land, Infrastructure, Transport and Tourism is such that the standard value for inclination is within 1/100 and the standard value for deviation of pile center is within 1/4 of the pile diameter and within 100 mm. Therefore, at the time of construction, it is necessary to carefully manage the accuracy during rotary penetration, that is, the verticality and the amount of eccentricity (amount of misalignment) of the pile.

Conventionally, the verticality of piles has been confirmed by means of transits, inclinometers, levels, etc. during rotary penetration and before site joining of upper and middle piles. On the other hand, the amount of eccentricity of the pile is measured from the two relief centers (for example, the reference of the reinforcing bar) installed at a certain distance from the construction reference of the pile center during the rotation penetration and before the site joining of the upper pile and the middle pile. It was confirmed by measuring the distance to the outer peripheral surface of the with a standard length stick. However, the measurement requires manpower and time, and the operator cannot check the measured values during rotation penetration in real time. There is a risk that the pile will be damaged and the construction period will be extended.

Therefore, in the construction method described in Patent Document 1 (hereinafter referred to as "conventional construction method"), GNSS is attached to the ends of rod-shaped members projecting to the left and right of the chucking portion of the pile driver that grips the pile head. A receiver is provided, and the position of the pile in the three-dimensional coordinate system and the direction of rotation of the pile are measured from the difference between the two GNSS three-dimensional coordinate systems that are spaced left and right. It is configured to display the orientation in real time on the monitor.

JP 2015-48635 A

However, in the conventional construction method, the position information obtained from GNSS is the position information of the chucking part of the pile driver, not the actual measurement value of the position information of the pile. Variation in the pile center position with respect to the mounting center of the chucking portion and variation in inclination of the pile axis (center line) with respect to the chucking portion mounting center line are reflected in the variation in the pile position information (actual measurement values).

SUMMARY OF THE INVENTION An object of the present invention is to provide a pile foundation construction method and a construction management system capable of rotating and penetrating a cylindrical member such as a steel pipe or casing into the ground with high accuracy.

The pile foundation construction method of the present invention is a pile foundation construction method in which a cylindrical member is rotated and penetrated into the ground, and includes an antenna mounting step of mounting a GNSS antenna on the outer periphery of the opened head of the cylindrical member, and GNSS positioning. A position information generating step of generating position information of a cylindrical member from the obtained position information, a setting step of setting the cylindrical member while monitoring the position information of the cylindrical member in real time, and the cylindrical member and a rotational penetration step of rotationally penetrating the cylindrical member while monitoring positional information of the cylindrical member in real time.
The construction management system of the present invention includes a fixture fixed to the outer circumference of an open head of a cylindrical member, a GNSS antenna attached to the outer circumference of the fixture, and a cylinder based on position information received by the GNSS antenna. and a position information display means for displaying the position information of the cylindrical member.

According to the pile foundation construction method and construction management system of the present invention, a cylindrical member such as a steel pipe or casing can be rotated and penetrated into the ground with high accuracy.

1 is an explanatory diagram of the first embodiment and a conceptual diagram of a positioning system; FIG. 2 is a plan view of a fixture used in the positioning system of FIG. 1; FIG. FIG. 4 is an explanatory diagram of the first embodiment, and is a diagram showing an example of the position information of stakes displayed on the display of the terminal device. FIG. It is a construction flow chart in a 1st embodiment. It is explanatory drawing from (A) to (D) of the construction procedure in 1st Embodiment. It is explanatory drawing from (E) to (H) of the construction procedure in 1st Embodiment. It is a construction flow chart in a 2nd embodiment. It is explanatory drawing from (A) to (D) of the construction procedure in 2nd Embodiment. It is explanatory drawing from (E) to (H) of the construction procedure in 2nd Embodiment.

(First embodiment)
A first embodiment of the present invention will be described with reference to the accompanying drawings.
In the first embodiment, application to a rotary pile construction method by a body rotation method in which a rotation force is applied to the body of a pile 31 (see FIG. 1) using a full circumference rotary machine 5 (excavator) will be described. In addition, the rotary pile construction method ("NS Ecopile [registered trademark] construction method, see Figs. 5 and 6" in the first embodiment) is a steel pipe with a blade 33 (see Fig. 5 (A)) at the tip. This is a construction method in which the pile 31 (cylindrical member) of is rotated and penetrated into the ground 6.

Here, the construction management system used for the rotary pile construction method (pile foundation construction method) according to the first embodiment will be described. The construction management system in the first embodiment includes an existing construction management device (not shown) that monitors the measured values of management items during rotation penetration of the pile 31, and a positioning system 1 based on GNSS (Global Navigation Satellite System) positioning. Prepare. For GNSS positioning, RTK (Real Time Kinematic)-GNSS positioning is applied. For RTK-GNSS positioning, an RTK system with fixed stations installed or a network RTK system such as VRS (Virtual Reference Station) or RRS (Real Reference Station) is applied.

FIG. 1 shows a conceptual diagram of the positioning system 11. As shown in FIG. For the purpose of simplifying the description of the specification, illustration of the existing construction management device is omitted. As shown in FIG. 1, the positioning system 11 comprises two GNSS receivers 12,12. GNSS receivers 12, 12 receive signals (positional information) transmitted from a plurality of GNSS satellites 1 (only one is shown in FIG. 1), and GNSS antennas 13, 13 receive signals (positional information). a positioning unit 14 for generating position information from the signals.

In addition, the positioning system 11 generates the position information of the stake 31 based on the positioning information of the GNSS receivers 12, 12, that is, the position information of each mobile station (GNSS antennas 13, 13) generated by the positioning units 14, 14. , and a relay unit 15 (position information generating means) that transmits the calculation results (vertical accuracy of the pile 31, the amount of eccentricity, and height information with respect to the construction reference plane) to terminal devices such as the tablet terminal 2 and the smartphone 3. Here, the communication method between the GNSS receivers 12, 12 and the relay unit 15, and the communication method between the relay unit 15 and terminal devices such as the tablet terminal 2 and the smartphone 3 are Wi-Fi (Wireless Fidelity) communication (wireless LAN communications) apply. In addition, the terminal device includes the tablet terminal 2, the smartphone 3, as well as a notebook computer and the like.

FIG. 3 shows an example of the display of the display 50 (position information display means) of the terminal device such as the tablet terminal 2 and the smartphone 3, that is, an example of the display of the position information of the pile 31 (cylindrical member) generated by the relay unit 15. indicates As shown in FIG. 3, the display of the display 50 includes a first display area 51 that displays the amount of eccentricity of the pile center, a second display area 61 that displays the inclination of the pile 31, and a construction base surface 72 of the pile 31. and a third display area 71 that displays the depth from.

In the first display area 51, the origin P0 (cross) of the planar coordinate system 52 indicates the design value of the target pile 31 (“Pile No. 2” in FIG. 3). Here, the X-axis of the planar coordinate system 52 is set so as to pass through the pile center P1 of the adjacent pile 31 (“Pile No. 1” in FIG. 3) displayed in the left portion of the first display area 51 . Of the concentric circles 53, 54, and 55 displayed in the first display area 51, the inner circle 53 is the management reference value of the pile center of the target pile 31, and the middle circle 54 is the pile center of the target pile 31. The standard values and the outer circle 55 indicate auxiliary lines. In the first embodiment, the auxiliary line indicates a value (eccentricity) obtained by adding 50 mm to the standard value.

Furthermore, in the first display area 51, the measured value P2 of the pile center of the target pile 31 is displayed. In the first display area 51, the circle 53, circle 54, circle 55, and measured value P2 are displayed in different colors. In addition, the numerical value of the eccentricity is displayed in the lower part of the first display area 51, "d" is the distance between the origin P0 and the measured value P2, "x" is the X coordinate of the measured value P2, and "y" is The Y coordinate of the measured value P2 is shown.

In the second display area 61, the horizontal axis 62 indicates the inclination of the target pile 31 in percentage (%). A line segment 63 displayed in the second display area 61 is a vertical line (inclination of 0%), a line segment 64 is an inclination control reference value (inclination of 0.4%), and a line segment 65 is an inclination standard value (inclination 1.0%), and line segment 66 indicates an auxiliary line (1.5%). In the first embodiment, the auxiliary line indicates a value (gradient) obtained by adding 0.5% to the standard value.

Furthermore, in the second display area 61, a line segment 67 indicating the actually measured value of the inclination of the target pile 31 is displayed. Also, in the lower right portion of the second display area 61, the actually measured value of the inclination of the target pile 31 is displayed as a numerical value. In the first embodiment, the area surrounded by the horizontal axis 62, the line segment 63 (vertical line), and the line segment 64 (control standard value) in the second display area 1 is differentiated and displayed (in FIG. 3 displayed in “grayscale”). In the second display area 61, a line segment 64 (control reference value), a line segment 65 (standard value), a line segment 66 (auxiliary line), and a line segment 67 (actual measurement value) are displayed in different colors. .

In the third display area, the line segment 72 extending horizontally on the upper side is the construction base surface, the line segment 73 extending horizontally on the lower side is the design value (target depth) of the depth of the target pile 31, and the line segment 72 and the line A line segment 74 extending vertically between the segment 73 indicates the depth of the target pile 31 . Also, in the third display area 71, an actual measurement value P3 (cumulative depth) of the depth of the target pile 31 is displayed. Furthermore, in the right part of the third display area 71, the remaining distance to the design value (the difference between the design value and the actual measurement value) is displayed. Note that the design value of the depth is displayed near the line segment 73 in the lower right portion of the third display area.

As shown in FIG. 1 , the GNSS antennas 13 , 13 are attached to the pile head 32 (the head of the cylindrical member) by fasteners 21 . The GNSS antennas 13, 13 attached to the pile head 32 are arranged line-symmetrically with respect to the axis (center line) of the pile 31 in a front view (see FIG. 5A), in other words, the pile 31 It is arranged point-symmetrically with respect to the pile center on a plane perpendicular to the axis of the pile. As shown in FIG. 2, the fixture 21 has a pair of strips 22, 22 formed in a semi-circular shape along the pile head 32, forming a circular shape when closed (see FIG. 2). The band bodies 22, 22 have belt portions 23, 23 made of band steel, and cushion portions 24, 24 made of rubber plates and provided on the inner peripheries of the belt portions 23, 23. As shown in FIG.

One ends of the belt portions 23 , 23 (“left end” in FIG. 2 ) are connected via a hinge 26 . On the other hand, the other ends (“right ends” in FIG. 2) of the belt portions 23, 23 are connected by fasteners 27 so as to be tightly bound. As a result, the connection (bonding) by the fastener 27 is released, and when the straps 22, 22 are rotated around the hinge 26 in the direction in which the other ends are separated to open the fixing tool 21, the stake between the straps 22, 22 is opened. A head 32 can be received. Brackets 28, 28 projecting in the radial direction (“vertical direction” in FIG. 2) are provided on the outer peripheries of the belt portions 23, 23. As shown in FIG. The positioning units 14 , 14 (housings) of the GNSS receivers 12 , 12 are fixed to the brackets 28 , 28 .

Next, based on the construction flow chart shown in FIG. 4, the construction procedure of the rotary pile construction method (NS Ecopile (registered trademark) construction method) using the positioning system 11 will be described.
First, the fixture 21 to which the GNSS antennas 13, 13 (GNSS receivers 12, 12) are attached is attached to the outer periphery of the pile head 32 of the pile 31 (cylindrical member) (“Step 1” in FIG. 4). . A blade 33 is provided at the tip of the pile 31 (lower pile) (the end opposite to the pile head 32).

Next, as shown in (A) of FIG. 5, the pile 31 (lower pile) to which the GNSS antennas 13, 13 are attached is lifted by a crane (not shown), and the pile 31 (lower pile) is erected. (“Step 2” in FIG. 4). At this time, the operator can confirm in real time the position information (installation accuracy) of the pile 31 displayed on the display 50 (see FIG. 3) of the terminal device such as the tablet terminal 2 and the smartphone 3. Illustrations related to preparatory work such as installation of the full-circumference rotary machine 5 (excavator) before erection are omitted.

Next, as shown in FIG. 5B, the all-around rotating machine 5 is operated to rotate and penetrate the pile 31 (lower pile) into the ground 6 ("Step 3" in FIG. 4). At this time, the operator can confirm the position information (construction accuracy) of the pile 31 (lower pile) displayed on the display 50 (see FIG. 3) of the terminal device such as the tablet terminal 2 and the smartphone 3 in real time.

Next, when the penetration depth of the pile 31 (lower pile) or the height of the pile head 32 (height information with respect to the construction base surface) reaches the design value, the rotary penetration by the all-around rotating machine 5 is stopped. , The GNSS antennas 13, 13 (GNSS receivers 12, 12) are replaced from the pile 31 (lower pile) whose rotation penetration has been completed to the pile 31 (upper pile or middle pile) to be rotated next (" Step 4"). At this time, the operator can confirm the penetration depth of the pile 31 (lower pile) or the height of the pile head 32 in real time by displaying the display 50 of the terminal device such as the tablet terminal 2 or the smartphone 3. Moreover, the GNSS antennas 13 and 13 are replaced by operating the fastener 27 to open and close the fixture 21 .

Next, as shown in FIG. 5C, the pile 31 (upper pile or middle pile) to which the GNSS antennas 13 and 13 are attached is lifted by a crane (not shown), and the pile 31 (upper pile or middle pile ) is erected (“Step 5” in FIG. 4). At this time, the operator can confirm in real time the position information (installation accuracy) of the pile 31 (upper pile or middle pile) displayed on the display 50 of the terminal device such as the tablet terminal 2 or the smartphone 3.

Next, as shown in FIG. 5 (D), the joint portion between the pile 31 (lower pile) and the pile 31 (upper pile or middle pile) to which the GNSS antennas 13, 13 are attached is welded all around ( “Step 6” in FIG. 4). Next, as shown in (E) of FIG. 6, the all-round rotating machine 5 is operated to rotate and penetrate the pile 31 (upper pile or middle pile) into the ground 6 ("Step 7" in FIG. 4). At this time, the operator can confirm the position information (construction accuracy) of the pile 31 (upper pile or middle pile) displayed on the display 50 of the terminal device such as the tablet terminal 2 or the smartphone 3 in real time.

Next, when the penetration depth of the pile 31 (upper pile or middle pile) or the height of the pile head 32 reaches the design value, the rotation penetration by the all-around rotating machine 5 is stopped, and the GNSS antennas 13, 13 ( The GNSS receivers 12, 12) are replaced from the piles 31 (upper piles or middle piles) to the Yatko 7 (cylindrical member) (“Step 8” in FIG. 4). At this time, the operator confirms the penetration depth of the pile 31 (upper pile or middle pile) or the height of the pile head 32 in real time by displaying the display 50 of the terminal device such as the tablet terminal 2 and the smartphone 3. can be done.

Next, as shown in (F) of FIG. 6, the Yatko 7 to which the GNSS antennas 13, 13 are attached is lifted by a crane (not shown), and the Yatko 7 is erected (“Step 9” in FIG. 4). ). At this time, the operator can confirm the erection accuracy of the Yatko 7 in real time based on the position information of the Yatko 7 displayed on the display 50 of the terminal device such as the tablet terminal 2 or the smartphone 3 .

Next, the all-around rotating machine 5 is operated to rotate and penetrate the Yatco 7 into the ground 6 (“Step 10” in FIG. 4). At this time, the operator can confirm the position information (construction accuracy) of the Yatko 7 displayed on the display 50 of the terminal device such as the tablet terminal 2 or the smartphone 3 in real time. Then, as shown in (G) of FIG. 6, at the point of stopping when the penetration depth or shaft head height of the Yatko 7 reaches the design value ("step 11" in FIG. 4), the full circumference rotation After stopping the rotary penetration by the machine 5 and confirming the stopping depth, etc., the GNSS antennas 13, 13 (GNSS receivers 12, 12) are recovered (“Step 12” in FIG. 4). Next, as shown in (H) of FIG. 6, after the yattco 7 is pulled out from the ground 6 by a crane, pile hole processing is performed ("step 13" in FIG. 4), and construction is finished.

Here, in the conventional construction method, the plumbness of the pile was confirmed by a transit, an inclinometer, a level, etc. during the rotation penetration and before the site joining of the upper pile and the middle pile. On the other hand, the amount of eccentricity of the pile is the distance from the position of the two relief centers set at a certain distance from the construction standard of the pile center to the outer peripheral surface of the pile during the rotation penetration and before the site joining of the upper pile and the middle pile. It was confirmed by measuring with a standard length stick. In this way, the conventional construction method requires manpower and time for measurement, and since the operator cannot check the measured values in real time during rotary penetration, it is difficult to correct the pile center position and the slope of the pile. If this occurs, there is a risk that the piles will be damaged due to forced rebuilding, or that the construction period will be extended.

On the other hand, in the first embodiment, by fixing the fixture 21 to which the GNSS antennas 13, 13 (GNSS receivers 12, 12) are attached to the pile head 32 of the pile 31 (cylindrical member), the GNSS The antennas 13, 13 are arranged line-symmetrically with respect to the axis of the pile 31, in other words, they are arranged point-symmetrically with respect to the center of the pile on a plane perpendicular to the axis of the pile 31, and the GNSS antennas 13, 13 receive Based on the position information obtained, the position information of the pile 31 is generated by the relay unit 15 (position information generating means), and the position information of the pile 31 (vertical accuracy of the pile 31, the amount of eccentricity, and the height from the construction reference plane) is displayed on the display 50 (position information display means) of the terminal device such as the tablet terminal 2 and the smartphone 3.

According to the first embodiment, since the operator can confirm the position information of the pile 31 in real time, it is possible to improve the finished shape accuracy of the pile 31 . In addition, since the GNSS antennas 13, 13 are directly attached to the pile head 32 using the fixture 21, it is possible to suppress variations in the positional information of the piles 31 and, by extension, variations in the finished shape accuracy of the piles 31. . Furthermore, since manpower and time (effort) related to measurement as in the conventional construction method are not required, it is possible to shorten the construction period, and furthermore, it is possible to prevent damage to the pile 31 due to unreasonable rebuilding. .

(Second embodiment)
Next, a second embodiment will be described with reference to FIGS. 7 to 9. FIG.
Note that the same designations and reference numerals are used for common parts with the first embodiment, and redundant explanations are omitted.

1st Embodiment demonstrated the aspect applied to the rotary pile construction method (NS eco-pile (trademark) construction method). On the other hand, in the second embodiment, a mode applied to the all-casing construction method will be described. Hereinafter, the construction procedure of the all-casing construction method using the positioning system 11 will be described based on the construction flow diagram shown in FIG.

First, the fixture 21 to which the GNSS antennas 13, 13 (GNSS receivers 12, 12) are attached is attached to the outer periphery of the head (the head of the cylindrical member) of the casing 41 (first casing) (Fig. 7 "Step 1" in ). A tip 43 for cutting is provided at the tip of the casing 41 (first casing).

Next, as shown in FIG. 8A, the casing 41 (first casing) to which the GNSS antennas 13, 13 are attached is lifted by a crane (not shown), and the casing 41 (first casing) is erected. (“Step 2” in FIG. 7). At this time, the operator can confirm in real time the position information (installation accuracy) of the casing 41 (first casing) displayed on the display 50 (see FIG. 3) of the terminal device such as the tablet terminal 2 or the smartphone 3. can. Illustrations related to preparatory work such as installation of the full-circumference rotary machine 5 (excavator) before erection are omitted.

Next, as shown in FIG. 8B, the all-around rotating machine 5 is operated to rotate and penetrate the casing 41 (first casing) into the ground 6 ("Step 3" in FIG. 7). At this time, the operator can confirm the position information (construction accuracy) of the casing 41 (first casing) displayed on the display 50 (see FIG. 3) of the terminal device such as the tablet terminal 2 and the smartphone 3 in real time. .

Next, when the depth of penetration or the height of the head of the casing 41 (first casing) reaches the design value, the rotation penetration by the all-around rotating machine 5 is stopped, and the GNSS antennas 13, 13 (GNSS receiver 12 , 12) from the casing 41 (first casing) to the casing 41 (second casing) (“step 4” in FIG. 7). At this time, the operator can confirm the depth of penetration of the casing 41 (first casing) or the height of the head in real time through the display on the display 50 of the terminal device such as the tablet terminal 2 or the smartphone 3 . Moreover, the GNSS antennas 13 and 13 are replaced by operating the fastener 27 to open and close the fixture 21 .

Next, as shown in FIG. 8C, the hammer grub 45 excavates the inside of the casing 41 (the first casing) and removes underground obstacles such as earth and sand ("step 5" in FIG. 8). . Note that the rotational penetration of the casing 41 (first casing) (“Step 3” in FIG. 8) and the excavation and underground obstacle removal (“Step 5” in FIG. 8) can be performed in parallel.

Next, the casing 41 (second casing) to which the GNSS antennas 13, 13 are attached is lifted by a crane (not shown), and the casing 41 (second casing) is erected (“step 6” in FIG. 8). At this time, the operator can confirm the positional information (installation accuracy) of the casing 41 (second casing) displayed on the display 50 of the terminal device such as the tablet terminal 2 and the smartphone 3 in real time.

Next, as shown in (D) of FIG. 8, the casing 41 (first casing) and the casing 41 (second casing) to be buried next are connected ("step 7" in FIG. 8). Next, the all-around rotating machine 5 is operated to rotate and penetrate the casing 41 (second casing) into the ground 6 (“step 8” in FIG. 7). At this time, the operator can confirm the position information (construction accuracy) of the casing 41 (second casing) displayed on the display 50 of the terminal device such as the tablet terminal 2 or the smartphone 3 in real time.

Then, as shown in (E) of FIG. 9, until the final rotation penetration of the casing 41 and the excavation inside the casing 41 after the rotation penetration and the removal of the underground obstruction are completed ("step 9" in FIG. 7). ), and the steps from excavation/removal of underground obstacles (“Step 5” in FIG. 7) to rotary penetration (“Step 8” in FIG. 7) are repeated. Then, after the final rotational penetration of the casing 41 and the completion of the excavation inside the casing 41 and the removal of underground obstacles (“step 9” in FIG. 7), the GNSS antennas 13, 13 (GNSS receivers 12, 12) are recovered. (“Step 10” in FIG. 7).

Next, as shown in (F) of FIG. 9, a reinforcing bar cage 46 and a tremie tube 47 are erected in the buried casing 41 ("step 11" in FIG. 7). Next, as shown in FIG. 9G, concrete is poured into the embedded casing 41 and the tremie pipe 47 in the casing 41 is pulled out by a crane ("step 12" in FIG. 7). Next, as shown in (H) of FIG. 9, after the casing 41 is pulled out from the ground 6 by a crane, pile hole processing is performed (“Step 13” in FIG. 7), and construction is completed.

In the second embodiment, effects equivalent to those of the first embodiment can be obtained.

11 positioning system (construction management system), 13 GNSS antenna, 15 relay device (position information generating means), 21 fixture, 31 stake (cylindrical member), 50 display (position information display means)

Claims (8)

A pile foundation construction method for rotating and penetrating a cylindrical member into the ground,
An antenna mounting step for mounting the GNSS antenna on the outer circumference of the open head of the cylindrical member;
a position information generating step of generating position information of the cylindrical member from the position information obtained by GNSS positioning;
A erecting step of erecting the cylindrical member while monitoring the position information of the cylindrical member in real time;
A rotational penetration step of performing rotational penetration of the cylindrical member while monitoring the positional information of the cylindrical member in real time;
A pile foundation construction method comprising: The pile foundation construction method according to claim 1,
In the antenna mounting step,
A pile foundation construction method characterized by arranging GNSS antennas at two locations symmetrically with respect to the axis of a cylindrical member. The pile foundation construction method according to claim 1 or 2,
A pile foundation construction method, comprising an antenna replacement step of replacing the GNSS antenna from a cylindrical member in which rotational penetration has been completed to a cylindrical member to be subsequently rotated and penetrated. The pile foundation construction method according to any one of claims 1 to 3,
The pile foundation construction method, wherein the position information of the cylindrical member is vertical accuracy, eccentricity, and depth information with respect to the construction base surface. A construction management system used in the pile foundation construction method according to claims 1 to 4,
a fixture fixed to the outer circumference of the open head of the cylindrical member;
a GNSS antenna attached to the outer periphery of the fixture;
position information generating means for generating position information of the cylindrical member based on the position information received by the GNSS antenna;
position information display means for displaying position information of the cylindrical member;
A construction management system comprising: The construction management system according to claim 5,
The construction management system, wherein the GNSS antennas are arranged at two locations symmetrically with respect to the axis of the cylindrical member. The construction management system according to claim 5 or 6,
The fixture comprises a pair of semi-circular straps, a hinge connecting one end of the pair of straps, and a fastener releasably connecting the other end of the pair of straps. Characteristic construction management system. The construction management system according to any one of claims 5 to 7,
The construction management system, wherein the position information display means is a display of a terminal device.

Images