JP2024058255A - Inclination measurement device and inclination angle measurement method of steel cylindrical body - Google Patents

Inclination measurement device and inclination angle measurement method of steel cylindrical body Download PDF

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JP2024058255A
JP2024058255A JP2022165504A JP2022165504A JP2024058255A JP 2024058255 A JP2024058255 A JP 2024058255A JP 2022165504 A JP2022165504 A JP 2022165504A JP 2022165504 A JP2022165504 A JP 2022165504A JP 2024058255 A JP2024058255 A JP 2024058255A
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cylindrical body
steel
accelerometer
steel cylindrical
inclination
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JP7235927B1 (en
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一弘 奥田
Kazuhiro Okuda
浩一郎 梯
Koichiro Kakehashi
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Penta Ocean Construction Co Ltd
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Abstract

To provide an inclination measurement device and an inclination angle measurement method for a steel cylindrical body which can simply and accurately monitor the inclination of a steel pipe, a steel pipe sheet pile and the like at real time.SOLUTION: An inclination measurement device 2 includes: an accelerometer 4 which is fixed to an inner peripheral surface at a predetermined height position that is a reference position from the lower end of a steel cylindrical body 1 through an accelerometer mounting member 3; a protective cover 5 which is fixed to the inner peripheral surface of the steel cylindrical body 1, and covers the accelerometer 4 held by the accelerometer mounting member 3; and horizontal displacement amount calculation means 6 for calculating a horizontal displacement amount L at a reference position of the steel cylindrical body 1 for each predetermined installation depth ln on the basis of measurement data of the accelerometer 4.SELECTED DRAWING: Figure 1

Description

本発明は、鋼管矢板や鋼管杭等の鋼製筒状体を地盤に打設する際の鋼製筒状体の傾斜角を計測する鋼製筒状体の傾斜計測装置及び傾斜角計測方法に関する。 The present invention relates to a steel cylindrical body inclination measurement device and inclination angle measurement method that measures the inclination angle of a steel cylindrical body, such as a steel pipe sheet pile or a steel pipe pile, when the steel cylindrical body is driven into the ground.

鋼管杭や鋼管矢板等の鋼製筒状体を直杭として地盤に打設する際には、導材等によって鋼製筒状体を垂直に建て込んだ状態で杭打機によって鋼製筒状体の上端を打撃又は押し込むことにより地盤に貫入させるようになっている。 When driving a steel tubular body such as a steel pipe pile or steel pipe sheet pile into the ground as a straight pile, the steel tubular body is erected vertically using a guide material or the like, and then the top end of the steel tubular body is struck or pushed in by a pile driver to penetrate the ground.

しかしながら、杭打機により鋼製筒状体を地盤に対し垂直方向に打設しようとしても、地盤からの抵抗や地盤内の岩、地質等の状況によって打設途中の鋼製筒状体に傾きが生じる場合がある。 However, even if you try to drive a steel tubular body vertically into the ground using a pile driver, the steel tubular body may tilt during driving due to resistance from the ground or the rocks and geology in the ground.

その場合、傾いた状態に気づかずに打設し続けると、鋼製筒状体の傾斜が進み、既製杭（鋼管杭やコンクリート杭）の打設に関する一般的な管理基準で定められた許容範囲、詳しくは、平面的に見た場合の偏心量が杭径の１／４且つ１００ｍｍ以下、杭の傾斜が１／１００以下という許容範囲を超えてしまうおそれがある。 In this case, if driving continues without noticing the tilted state, the steel tubular body will continue to tilt, and there is a risk that it will exceed the allowable range set by the general management standards for driving prefabricated piles (steel pipe piles and concrete piles), specifically, the amount of eccentricity when viewed from a plan view must be 1/4 of the pile diameter and 100 mm or less, and the inclination of the pile must be 1/100 or less.

よって、このような鋼製筒状体の打設においては、打設途中における鋼製筒状体の傾きを随時監視する必要がある。 Therefore, when casting such a steel tubular body, it is necessary to constantly monitor the inclination of the steel tubular body during casting.

従来では、例えば、打設する鋼製筒状体から一定の距離をおいて複数の光学式水準器を設置し、水準器で鋼製筒状体の上端部を計測して鋼製筒状体の傾きを監視する方法等や鋼管杭の上端部に傾斜計を設置し、鋼製筒状体の傾斜を計測する方法（例えば、特許文献１を参照）等が知られている。 Conventionally, for example, methods have been known in which multiple optical levels are placed at a fixed distance from the steel tubular body to be cast, and the levels are used to measure the upper end of the steel tubular body to monitor its inclination, or a method has been known in which an inclinometer is placed at the upper end of a steel pipe pile to measure the inclination of the steel tubular body (see, for example, Patent Document 1).

特開平１－３９５１５号公報Japanese Patent Application Laid-Open No. 1-39515

しかしながら、上述の如き従来の水準器を使用した監視方法では、打設位置から離れた位置に設置した水準器により作業員が目視で観察するため、作業が煩雑であるという問題があった。 However, the above-mentioned conventional monitoring method using a level has the problem that the worker must visually observe the concrete pouring position using a level installed at a position away from the pouring position, making the work complicated.

また、鋼製筒状体の打設地点が水底である場合等では、監視位置が水上になるため、打設地点の近辺に陸が無ければ水準器を船舶上に設置しなければならず、船舶上に設置された水準器では、水面のうねり等によって正確な計測ができず、水準器での監視が困難であるという問題もあった。 In addition, when the steel cylindrical body is cast at the bottom of the water, the monitoring position is above water, and if there is no land near the casting point, a spirit level must be installed on a ship. However, a spirit level installed on a ship cannot take accurate measurements due to swells on the water surface, making monitoring with the spirit level difficult.

さらに、上述の如き従来の技術では、一定距離を隔てた位置での測定となるので、天候によっては視認が遮られ、リアルタイムで鋼製筒状体の傾きを把握することができないという問題があった。 Furthermore, with the conventional technology described above, measurements are taken at a fixed distance away, so visibility can be blocked depending on the weather, making it impossible to grasp the inclination of the steel cylindrical body in real time.

また、従来の傾斜計を用いる方法では、傾斜計を鋼製筒状体の上部に取り付けるため、地盤に打設された部分の傾斜状態を十分に把握できないという問題があった。 In addition, the conventional method using an inclinometer requires attaching the inclinometer to the top of a steel cylindrical body, which means that it is difficult to fully grasp the inclination state of the part that is cast into the ground.

そこで、本発明は、このような従来の問題に鑑み、簡便に鋼管や鋼管矢板等の傾斜をリアルタイムで正確に監視することができる鋼製筒状体の傾斜計測装置及び傾斜角計測方法の提供を目的としてなされたものである。 In view of these conventional problems, the present invention aims to provide an inclination measurement device and an inclination angle measurement method for steel cylindrical bodies that can easily and accurately monitor the inclination of steel pipes, steel pipe sheet piles, etc. in real time.

上述の如き従来の問題を解決するための請求項1に記載の発明の特徴は、打撃又は押し込むことにより地盤に打設される鋼製筒状体の傾斜を計測する鋼製筒状体の傾斜計測装置において、前記鋼製筒状体の下端より基準位置である所定の高さ位置の内周面に加速度計取付部材を介して固定された加速度計と、前記鋼製筒状体の内周面に固定され、前記加速度計取付部材に保持された前記加速度計を覆う保護カバーと、前記加速度計の計測データに基づき所定の打設深度毎に前記鋼製筒状体の前記基準位置の水平方向変位量を算出する水平変位量算出手段とを備えていることにある。 The invention described in claim 1, which aims to solve the above-mentioned problems of the prior art, is characterized in that the device for measuring the inclination of a steel cylindrical body, which is driven into the ground by striking or pushing, is provided with an accelerometer fixed via an accelerometer mounting member to the inner surface of the steel cylindrical body at a predetermined height position, which is a reference position, from the lower end of the steel cylindrical body, a protective cover that is fixed to the inner surface of the steel cylindrical body and covers the accelerometer held by the accelerometer mounting member, and a horizontal displacement amount calculation means that calculates the horizontal displacement amount of the reference position of the steel cylindrical body for each predetermined casting depth based on the measurement data of the accelerometer.

請求項２に記載の発明の特徴は、請求項１の構成に加え、複数の前記加速度計が筒軸方向に互いに間隔をおいて固定されていることにある。 The invention described in claim 2 is characterized in that, in addition to the configuration of claim 1, the multiple accelerometers are fixed at intervals from each other in the cylindrical axis direction.

請求項３に記載の発明の特徴は、請求項１又は２の構成に加え、前記保護カバーは、前記鋼製筒状体の上端まで連続し、下端部が閉鎖されていることにある。 The invention described in claim 3 is characterized in that, in addition to the configuration of claim 1 or 2, the protective cover is continuous to the upper end of the steel cylindrical body and the lower end is closed.

請求項４に記載の発明の特徴は、打撃又は押し込むことにより地盤に打設される鋼製筒状体の傾斜を計測する鋼製筒状体の傾斜計測方法において、前記鋼製筒状体の下端より所定の高さ位置の内周面に加速度計取付部材を介して加速度計を固定しておき、所定の打設深度毎に前記加速度計によって前記鋼製筒状体の傾斜角を計測し、該計測された傾斜角と打設深度に基づき前記鋼製筒状体の基準位置における水平方向変位を算出することにある。 The invention described in claim 4 is characterized in that, in a method for measuring the inclination of a steel tubular body that is driven into the ground by striking or pushing, an accelerometer is fixed to the inner surface of the steel tubular body at a predetermined height from the lower end thereof via an accelerometer mounting member, the inclination angle of the steel tubular body is measured by the accelerometer for each predetermined casting depth, and the horizontal displacement of the steel tubular body at a reference position is calculated based on the measured inclination angle and the casting depth.

本発明に係る鋼製筒状体の傾斜計測装置は、請求項１に記載の構成を具備することによって、簡便な構造で鋼管や鋼管矢板等の傾斜をリアルタイムで監視することができる。 The inclination measurement device for a steel cylindrical body according to the present invention has the configuration described in claim 1, and can monitor the inclination of steel pipes, steel pipe sheet piles, etc. in real time with a simple structure.

また、本発明において、請求項２に記載の構成を具備することにより、何れかの加速度計が故障や破損した場合にも計測を実行することができる。また、複数の加速度計の計測結果に基づき誤差の修正をすることができる。 In addition, by providing the configuration described in claim 2, the present invention can perform measurements even if any of the accelerometers fails or breaks. Also, errors can be corrected based on the measurement results of multiple accelerometers.

さらに、本発明において、請求項３に記載の構成を具備することによって、加速度計と地上の装置とを有線で接続することができるとともに、当該接続ケーブルを保護することができる。 Furthermore, in the present invention, by providing the configuration described in claim 3, the accelerometer and the ground device can be connected by wire, and the connection cable can be protected.

本発明に係る鋼製筒状体の傾斜計測方法は、請求項４に記載の構成を具備することによって、簡便に鋼管や鋼管矢板等の傾斜をリアルタイムで監視することができる。 The method for measuring the inclination of a steel cylindrical body according to the present invention has the configuration described in claim 4, making it possible to easily monitor the inclination of steel pipes, steel pipe sheet piles, etc. in real time.

（ａ）本発明に係る構成筒状体の傾斜計測装置の実施例を示す平面図、（ｂ）は同Ａ－Ａ線矢視断面図である。FIG. 2A is a plan view showing an embodiment of the inclination measurement device for a cylindrical body according to the present invention, and FIG. 2B is a cross-sectional view taken along line AA of the same. 図１中の加速度計の取り付け部分を示す拡大断面図である。FIG. 2 is an enlarged cross-sectional view showing a mounting portion of an accelerometer in FIG. 1 . 図２中に示すＢ－Ｂ線矢視拡大断面図である。3 is an enlarged cross-sectional view taken along line BB in FIG. 2. 図３中に示すＣ－Ｃ線矢視断面図である。4 is a cross-sectional view taken along the line CC in FIG. 3. （ａ）は図１（ａ）中の保護カバー下端部分を示す正面図、（ｂ）は同側面図である。1A is a front view showing a lower end portion of the protective cover in FIG. 1A, and FIG. 本発明の計測原理を説明するための概略断面図である。FIG. 2 is a schematic cross-sectional view for explaining the measurement principle of the present invention. （ａ）～（ｄ）は本発明に係る鋼製筒状体の傾斜計測方法の手順を示す概略断面図である。5A to 5D are schematic cross-sectional views showing the steps of the method for measuring the inclination of a steel cylindrical body according to the present invention.

次に、本発明に係る構成筒状体の傾斜計測装置２の実施態様を図１～図６に示した実施例に基づいて説明する。尚、図中符号１は鋼管杭や鋼管矢板等の鋼製筒状体である。 Next, an embodiment of the inclination measurement device 2 for a cylindrical body according to the present invention will be described based on the examples shown in Figures 1 to 6. In the figures, reference numeral 1 denotes a steel cylindrical body such as a steel pipe pile or a steel pipe sheet pile.

鋼製筒状体１は、鋼管杭や鋼管矢板等の鋼製の上下端が開口した一定長さを有する筒状に形成され、バイブロハンマや杭打機等によって打撃又は押し込むことにより地盤４０に打設されるようになっている。 The steel tubular body 1 is made of steel, such as a steel pipe pile or steel pipe sheet pile, and is formed into a cylindrical shape of a certain length with open top and bottom ends, and is designed to be driven into the ground 40 by striking or pushing it with a vibro hammer, pile driver, etc.

尚、鋼製筒状体１は、図１に示す円筒状に限定されず、角筒状や多角形筒状であってもよい。 The steel tubular body 1 is not limited to the cylindrical shape shown in FIG. 1, but may be a square or polygonal tubular shape.

この鋼製筒状体１は、導材等によって垂直に建て込んだ状態で杭打機等によって鋼製筒状体１の上端を打撃又は押し込むことにより地盤４０に貫入させるようになっている。 This steel tubular body 1 is erected vertically using conductors or the like, and then penetrated into the ground 40 by striking or pushing the upper end of the steel tubular body 1 with a pile driver or the like.

その際、鋼製筒状体１は、傾斜計測装置２によって打設途中における鋼製筒状体１の傾きが随時監視できるようになっている。 At this time, the inclination of the steel cylindrical body 1 during casting can be monitored at any time by the inclination measuring device 2.

この傾斜計測装置２は、図１に示すように、鋼製筒状体１の下端より所定の距離をおいた基準位置である所定の高さ位置の内周面に加速度計取付部材３を介して固定された加速度計４，４と、鋼製筒状体１の内周面に固定され、加速度計取付部材３に保持された加速度計４，４を覆う保護カバー５と、加速度計４，４の計測データに基づき所定の打設深度ｌｎ毎に鋼製筒状体１の基準位置の水平方向変位量Ｌｎを算出する水平変位量算出手段６とを備えている。 As shown in Figure 1, this inclination measurement device 2 comprises accelerometers 4, 4 fixed via accelerometer mounting members 3 to the inner surface of the steel tubular body 1 at a predetermined height position, which is a reference position a predetermined distance from the lower end of the steel tubular body 1, a protective cover 5 fixed to the inner surface of the steel tubular body 1 and covering the accelerometers 4, 4 held by the accelerometer mounting members 3, and a horizontal displacement amount calculation means 6 which calculates the horizontal displacement amount Ln of the reference position of the steel tubular body 1 for each predetermined casting depth ln based on the measurement data of the accelerometers 4, 4.

加速度計取付部材３は、図３に示すように、平板状の加速度計取付板１０と、加速度計取付板１０の両側縁より加速度計取付板１０に対し鋼製筒状体の内周面に向け略直角方向に延出した板状の側板部１１，１１とを備え、断面視コ字状に形成され、両側板部１１，１１の短手方向端縁が溶接により基準位置である所定の高さ位置で鋼製筒状内周面に固定されている。尚、この加速度計取付部材３には、一般的な溝形鋼等を用いることができる。 As shown in FIG. 3, the accelerometer mounting member 3 comprises a flat accelerometer mounting plate 10 and plate-like side plate portions 11, 11 extending from both side edges of the accelerometer mounting plate 10 in a direction approximately perpendicular to the inner peripheral surface of the steel cylindrical body, and is formed in a U-shape in cross section, with the short end edges of both side plate portions 11, 11 fixed to the inner peripheral surface of the steel cylindrical body at a predetermined height position, which is the reference position, by welding. Note that general channel steel or the like can be used for this accelerometer mounting member 3.

加速度計取付部材３は、図２に示すように、少なくとも一つが鋼製筒状体１の下端より基準位置である所定の高さ位置の鋼製筒状体１の内周面に長手方向を筒軸方向に向けて固定され、その他の加速度計取付部材３，３がそれぞれ筒軸方向で連続する配置に固定され、複数（少なくとも二つ）の加速度計４，４が筒軸方向に所定の間隔をおいて連続的に配置されるようになっている。 As shown in FIG. 2, at least one accelerometer mounting member 3 is fixed to the inner surface of the steel cylindrical body 1 at a predetermined height position, which is a reference position from the lower end of the steel cylindrical body 1, with its longitudinal direction facing the cylindrical axis direction, and the other accelerometer mounting members 3, 3 are fixed in a continuous arrangement in the cylindrical axis direction, so that multiple (at least two) accelerometers 4, 4 are continuously arranged at a predetermined interval in the cylindrical axis direction.

尚、本実施形態においては、鋼製筒状体１の下端部の打設時の状態を考慮し、鋼製筒状体１の下端より略１ｍ上方を基準位置として設定しているが、杭先端部の状況予測によっては、より下方に設けてもよい。 In this embodiment, the reference position is set approximately 1 m above the bottom end of the steel tubular body 1, taking into consideration the condition of the bottom end of the steel tubular body 1 when it is cast, but it may be set lower depending on the predicted condition of the tip of the pile.

また、もう一つ取り付ける加速度計４は、基準位置に設置した加速度計４が打設に伴い破損した場合のバックアップ用として設置することから、加速度計４が取り付けられた基準位置からの間隔はあまり長くせず、１ｍ程度が望ましい。 The other accelerometer 4 is installed as a backup in case the accelerometer 4 installed at the reference position is damaged during concrete pouring, so the distance from the reference position to the accelerometer 4 should not be too long, preferably about 1 m.

各加速度計取付部材３には、図２～４に示すように、加速度計取付板１０の表面側にボルト締め等によって収容ケース１２が固定され、収容ケース１２を介して加速度計４，４が固定されるようになっている。 As shown in Figures 2 to 4, each accelerometer mounting member 3 has a housing case 12 fixed to the front side of the accelerometer mounting plate 10 by bolting or the like, and the accelerometers 4, 4 are fixed via the housing case 12.

収容ケース１２は、細板状の底板１２ａと、底板１２ａの短辺の両端部上に立ち上げた端壁部１２ｂ，１２ｂと、底板１２ａの長辺の両端部上に立ち上げた側壁部１２ｃ，１２ｃと、底板１２ａの底面部と加速度計取付板１０の表面との間に配置され、収容ケース１２の長辺方向に間隔をおいて固定された複数の取付板１２ｄ，１２ｄ…とを備え、各取付板１２ｄ，１２ｄ…のボルト挿通孔１２ｅ，１２ｅを対応する加速度計取付板１０のボルト挿通孔１０ａ，１０ａの位置に合わせ、取付板１２ｄを貫通させたボルト１３に加速度計取付板１０の裏面側からナット１４を螺合させることによって固定されている。 The storage case 12 comprises a thin bottom plate 12a, end walls 12b, 12b raised on both ends of the short side of the bottom plate 12a, side walls 12c, 12c raised on both ends of the long side of the bottom plate 12a, and a number of mounting plates 12d, 12d... arranged between the bottom surface of the bottom plate 12a and the surface of the accelerometer mounting plate 10 and fixed at intervals in the long side direction of the storage case 12. The bolt insertion holes 12e, 12e of each mounting plate 12d, 12d... are aligned with the corresponding bolt insertion holes 10a, 10a of the accelerometer mounting plate 10, and the mounting plate is fixed by screwing a nut 14 onto the bolt 13 that has passed through the mounting plate 12d from the back side of the accelerometer mounting plate 10.

加速度計４，４は、少なくとも２つの圧電性結晶がそれぞれ別々の軸の振動に反応するように配置され、ｘ、ｙ、ｚ方向の３軸の振動に基づき各軸の加速度を計測する３軸加速度計で構成され、有線で水平変位量算出手段６と接続されている。尚、図中符号１５は加速度計４への電源供給及び加速度計４の計測データを送信するための接続ケーブル１５であって、この接続ケール１５が加速度計４本体と水平変位量算出手段６とを接続している。 The accelerometers 4, 4 are configured as three-axis accelerometers in which at least two piezoelectric crystals are arranged so that they respond to vibrations along different axes, and which measure the acceleration along each axis based on vibrations along three axes in the x, y, and z directions, and are connected to the horizontal displacement calculation means 6 by wire. Note that reference numeral 15 in the figure denotes a connection cable 15 for supplying power to the accelerometer 4 and transmitting the measurement data of the accelerometer 4, and this connection cable 15 connects the accelerometer 4 main body to the horizontal displacement calculation means 6.

加速度計４，４は、図４に示すように、収容ケース１２に収容され、ｘ軸を筒軸方向に、ｚ軸を管径方向にそれぞれ向けられるよう、収容ケース１２を介して加速度計取付部材３に固定されている。 As shown in FIG. 4, the accelerometers 4, 4 are housed in a housing case 12 and fixed to the accelerometer mounting member 3 via the housing case 12 so that the x-axis is oriented in the tube axis direction and the z-axis is oriented in the tube diameter direction.

また、加速度計４，４は、接続ケーブル１５の一部とともに収容ケース１２に収められ、収容ケース１２内に充填された樹脂材によって収容ケース１２に固定されている。 The accelerometers 4, 4 are housed in the housing case 12 together with a portion of the connection cable 15, and are fixed to the housing case 12 by a resin material filled in the housing case 12.

接続ケーブル１５は、収容ケース１２の上端開口部より引き出され、鋼製筒状体１の内周面に沿って鋼製筒状体１の上端開口部まで引き出され、鋼製筒状体１の上端部切り欠け又は上部側面の孔から水平変位量算出手段６に接続されている。 The connection cable 15 is pulled out from the upper opening of the storage case 12, pulled along the inner surface of the steel cylindrical body 1 to the upper opening of the steel cylindrical body 1, and connected to the horizontal displacement calculation means 6 through the notch at the upper end of the steel cylindrical body 1 or a hole in the upper side surface.

尚、接続ケーブル１５は、特に図示しないが、鋼製筒状体１の内周面に固定具によって固定されている。 Although not specifically shown, the connection cable 15 is fixed to the inner surface of the steel cylindrical body 1 by a fastener.

保護カバー５は、加速度計４，４及び加速度計取付部材３を覆うカバー本体２０と、カバー本体２０の下端部を閉鎖する先端用保護部材２１とを備え、鋼製筒状体１の下端より軸方向に所定の距離をおいた位置から上端部まで連続して鋼製筒状体１の内周面に固定されている。 The protective cover 5 comprises a cover body 20 that covers the accelerometers 4, 4 and the accelerometer mounting member 3, and a tip protective member 21 that closes the lower end of the cover body 20, and is fixed to the inner surface of the steel cylindrical body 1 continuously from a position that is a predetermined distance in the axial direction from the lower end of the steel cylindrical body 1 to the upper end.

カバー本体２０は、図３に示すように、細板状の天板２０ａと、天板２０ａの短辺両側縁より天板２０ａに対し鋼製筒状体１の内周面に向けて略直角方向に延出した板状の側板２０ｂ，２０ｂとを備え、平面視コ字状に形成され、両側板２０ｂ，２０ｂの短手方向端縁が溶接により鋼製筒状体１の内周面に固定されている。 As shown in FIG. 3, the cover body 20 is formed in a U-shape in a plan view and includes a thin top plate 20a and plate-like side plates 20b, 20b that extend from both short side edges of the top plate 20a toward the inner peripheral surface of the steel cylindrical body 1 at approximately right angles to the top plate 20a. The short side edges of both side plates 20b, 20b are fixed to the inner peripheral surface of the steel cylindrical body 1 by welding.

カバー本体２０は、天板２０ａの幅が加速度計取付部材３の幅よりも十分に幅広に形成されるとともに、両側板２０ｂ，２０ｂの幅（鋼製筒状体１内周面からの突出高さ）が天板２０ａと加速度計取付部材３に収容ケース１２を介して固定された加速度計４，４との間に一定の隙間が形成される幅に形成されている。 The cover body 20 is formed so that the width of the top plate 20a is sufficiently wider than the width of the accelerometer mounting member 3, and the width of both side plates 20b, 20b (protruding height from the inner peripheral surface of the steel cylindrical body 1) is such that a certain gap is formed between the top plate 20a and the accelerometers 4, 4 fixed to the accelerometer mounting member 3 via the housing case 12.

先端用保護部材２１は、図５に示すように、カバー本体２０の下端部の外周に沿って嵌合される断面視コ字状の嵌合部２１ａと、嵌合部２１ａの下端より下方外側（鋼製筒状体１内周面側）に傾斜した傾斜板２１ｂと、傾斜板２１ｂの両側部を塞ぐために配置された直角三角形状の両傾斜側板２１ｃ，２１ｃと、両傾斜側板２１ｃ，２１ｃ間に間隔をおいて配置された補強リブ２１ｄ，２１ｄとを備え、カバー本体２０の下端に嵌合され、カバー本体２０の下端を閉鎖している。 As shown in FIG. 5, the tip protection member 21 is fitted to the lower end of the cover body 20 along the outer periphery of the lower end of the cover body 20 and has a U-shaped fitting portion 21a in cross section, an inclined plate 21b inclined downward and outward (toward the inner periphery of the steel cylindrical body 1) from the lower end of the fitting portion 21a, two inclined side plates 21c, 21c in the shape of a right triangle arranged to close both sides of the inclined plate 21b, and reinforcing ribs 21d, 21d arranged at intervals between the two inclined side plates 21c, 21c. The tip protection member 21 is fitted to the lower end of the cover body 20 and closes the lower end of the cover body 20.

傾斜板２１ｂは、先端側に円弧状の掘削刃２１ｅが形成され、掘削刃２１ｅで地盤４０が掘削されることにより、先端用保護部材２１及びカバー本体２０が地盤４０に貫入される際の抵抗が軽減されている。 The inclined plate 21b has an arc-shaped excavation blade 21e formed on the tip side, and the excavation blade 21e excavates the ground 40, reducing resistance when the tip protection member 21 and the cover body 20 penetrate the ground 40.

水平変位量算出手段６は、パーソナルコンピュータ、タブレット端末等のコンピュータ機器に搭載されたプログラムよって構成され、加速度計４，４から出力されるデータを基に以下の式１～３により鋼製筒状体１の傾斜角θｎ、基準位置の水平方向変位量Ｌｎ及び加速度計４が設置されている先端部の累積水平変位量Ｌを算出するようになっている。尚、Ｋｘは加速度計４，４のｘ方向（筒軸方向）出力値（ｍ／ｓ２）、Ｋｚは加速度計４，４のｚ方向（管径方向）出力値（ｍ／ｓ２）、θｎは矢板の傾斜角、Ｇは重力加速度（ｍ／ｓ２）である。
（数式１）
θｎ＝ｔａｎ－１（Ｋｘ／Ｋｚ）
（数式２)
Ｌｎ＝ｌｎ×ｔａｎθｎ
（数式３）
Ｌ＝Ｌ０＋Ｌ１＋…＋Ｌｎ The horizontal displacement calculation means 6 is configured by a program installed in a computer device such as a personal computer or a tablet terminal, and is configured to calculate the inclination angle θn of the steel cylindrical body 1, the horizontal displacement Ln of the reference position, and the accumulated horizontal displacement L of the tip where the accelerometer 4 is installed, using the following equations 1 to 3 based on the data output from the accelerometers 4, 4. Note that Kx is the x-direction (cylinder axis direction) output value (m/s 2 ) of the accelerometers 4, 4, Kz is the z-direction (pipe diameter direction) output value (m/s 2 ) of the accelerometers 4, 4, θn is the inclination angle of the sheet pile, and G is the gravitational acceleration (m/s 2 ).
(Formula 1)
θ n =tan −1 (K x /K z )
(Formula 2)
Ln = ln × tan θn
(Formula 3)
L = L 0 + L 1 + ... + L n

尚、水平変位量算出手段６は、鋼製筒状体１を打設する打設船等に設置するが、加速度計４，４の計測データが無線で送信されるときには、陸上の事務所棟等に設置するようにしてもよい。 The horizontal displacement calculation means 6 is installed on a casting ship that casts the steel cylindrical body 1, but when the measurement data of the accelerometers 4, 4 is transmitted wirelessly, it may be installed in an office building on land, etc.

次に、上述の加速度計４を使用した鋼製筒状体１の傾斜計測方法について図７に基づいて説明する。尚、上述の実施例と同様の構成には同一符号を付して説明を省略する。 Next, a method for measuring the inclination of the steel cylindrical body 1 using the above-mentioned accelerometer 4 will be described with reference to FIG. 7. Note that the same components as those in the above-mentioned embodiment are given the same reference numerals and will not be described.

先ず、事前準備として、地上の工場や製作ヤードにおいて、打設する鋼管杭や鋼管矢板等の鋼製筒状体１の内側面の所定の位置に加速度計取付部材３を溶接等によって取り付け、加速度計取付部材３に収容ケース１２に収容された加速度計４，４を固定する。 First, as a preliminary preparation, in an above-ground factory or production yard, the accelerometer mounting member 3 is attached by welding or the like to a predetermined position on the inside surface of the steel cylindrical body 1, such as a steel pipe pile or steel pipe sheet pile, to be driven, and the accelerometers 4, 4 housed in the housing case 12 are fixed to the accelerometer mounting member 3.

また、各加速度計４，４本体から引き出された接続ケーブル１５を鋼製筒状体１の内周面軸方向に沿って這わせ、端部を鋼製筒状体１の上端開口部まで引き出しておく。尚、接続ケーブル１５は、鋼製筒状体１の上部開口部近くに設けた孔を通して鋼製筒状体１の外部に引き出すようにしてもよい。 The connection cables 15 pulled out from the main bodies of the accelerometers 4, 4 are laid along the axial direction of the inner periphery of the steel cylindrical body 1, and the ends are pulled out to the upper opening of the steel cylindrical body 1. The connection cables 15 may also be pulled out to the outside of the steel cylindrical body 1 through a hole provided near the upper opening of the steel cylindrical body 1.

そして、加速度計４，４の設置が完了したら、保護カバー５を加速度計取付部材３に収容ケース１２を介して取り付けられた加速度計４，４及び接続ケーブル１５を覆うように鋼製筒状体１の内周面に溶接によって固定する。また、保護カバー５の下端部に先端用保護部材２１を取り付ける。 After the installation of the accelerometers 4, 4 is completed, the protective cover 5 is fixed by welding to the inner surface of the steel cylindrical body 1 so as to cover the accelerometers 4, 4 and the connection cable 15 attached to the accelerometer mounting member 3 via the housing case 12. In addition, a tip protective member 21 is attached to the lower end of the protective cover 5.

次に、具体的な鋼製筒状体１の傾斜計測方法について説明する。 Next, we will explain a specific method for measuring the inclination of the steel cylindrical body 1.

先ず、図７（ａ）に示すように、鋼製筒状体１を測量により鉛直性を確保しつつ、下端部を一定深さ（以下、建て込み深さｌ０という）だけ地盤４０に貫入させた状態に建て込む。尚、図中符号４１は水面である。 First, as shown in Fig. 7(a), the steel cylindrical body 1 is erected with its lower end penetrating a certain depth (hereinafter referred to as the erection depth l0 ) into the ground 40 while ensuring its verticality by surveying. In the figure, the reference numeral 41 denotes the water surface.

そして、加速度計４，４による出力を開始し、出力された計測データに基づき水平変位量算出手段６が建て込み深さｌ０における鋼製筒状体１の傾斜角度（以下、初期傾斜角θ０という）及び先端部の水平変位量Ｌ０を上述した式１及び式２により算出する。 Then, output from the accelerometers 4, 4 is started, and based on the output measurement data, the horizontal displacement calculation means 6 calculates the inclination angle of the steel cylindrical body 1 at the erection depth l 0 (hereinafter referred to as the initial inclination angle θ 0 ) and the horizontal displacement amount L 0 of the tip portion using the above-mentioned equations 1 and 2.

尚、初期傾斜角θ０及び先端部の水平変位量Ｌ０の算出は、加速度計４，４による計測を１秒間に複数回行い、その平均値を測定値として行う。 The initial tilt angle θ 0 and the horizontal displacement amount L 0 of the tip are calculated by performing measurements by the accelerometers 4, 4 multiple times per second and averaging the measurements.

次に、鋼製筒状体１の打設を開始し、図７（ｂ）に示すように、建て込み深さより所定の深さ分ｌ１だけバイブロハンマや杭打機により鋼製筒状体１の上端を打撃又は押込み、鋼製筒状体１を所定の打設深度まで地盤４０に貫入させる。 Next, the casting of the steel tubular body 1 is started, and as shown in Figure 7 (b), the upper end of the steel tubular body 1 is struck or pushed in by a vibro hammer or pile driver to a predetermined depth l1 from the erection depth, so that the steel tubular body 1 penetrates into the ground 40 to the predetermined casting depth.

鋼製筒状体１を打設深度ｌ１だけ地盤４０に貫入させたら、一旦打設作業を停止し、振動が無い状態で加速度計４，４による計測を行い、出力された計測データに基づき水平変位量算出手段６が打設深度ｌ１における鋼製筒状体１の傾斜角度θ１及び先端部の単位貫入量当たりの水平変位量Ｌ１を式１及び式２により算出し、先端部の累積水平変位量Ｌ＝Ｌ０＋Ｌ１を式３により算出する。 Once the steel tubular body 1 has been penetrated into the ground 40 to a casting depth l1 , the casting work is stopped for a moment and measurements are taken using the accelerometers 4, 4 in an absence of vibration. Based on the output measurement data, the horizontal displacement calculation means 6 calculates the inclination angle θ1 of the steel tubular body 1 at the casting depth l1 and the horizontal displacement L1 per unit penetration at the tip using equations 1 and 2, and calculates the cumulative horizontal displacement L = L0 + L1 at the tip using equation 3.

尚、傾斜角θ１及び単位貫入量当たりの先端部の水平変位量Ｌ１の算出は、加速度計４，４による計測を１秒間に複数回行い、その平均値を測定値として行う。 The inclination angle θ1 and the horizontal displacement L1 of the tip per unit penetration are calculated by performing measurements with the accelerometers 4, 4 multiple times per second and averaging the measurements.

次に、鋼製筒状体１の打設を再開し、現位置から所定の深さ分ｌ２だけバイブロハンマや杭打機により鋼製筒状体１の上端を打撃又は押込み、鋼製筒状体１をさらに地盤４０に貫入させる。 Next, casting of the steel cylindrical body 1 is resumed, and the upper end of the steel cylindrical body 1 is struck or pushed in a predetermined depth l2 from the current position using a vibro hammer or pile driver, thereby penetrating the steel cylindrical body 1 further into the ground 40.

そして、鋼製筒状体１を打設深度ｌ2だけ地盤４０に貫入させたら、再度打設作業を停止し、振動が無い状態で加速度計４，４による計測を行い、出力された計測データに基づき水平変位量算出手段６が打設深度ｌ2分を貫入させた際の鋼製筒状体１の傾斜角度θ2及び先端部の打設深度ｌ2の水平変位量Ｌ2を式１及び式２により算出し、先端部の累積水平変位量Ｌ＝Ｌ０＋Ｌ１＋Ｌ２を式３により算出する。 Then, once the steel tubular body 1 has been penetrated into the ground 40 by a casting depth l2 , the casting work is stopped again and measurements are taken using the accelerometers 4, 4 in an absence of vibration. Based on the output measurement data, the horizontal displacement calculation means 6 calculates the inclination angle θ2 of the steel tubular body 1 when it has been penetrated by casting depth l2 and the horizontal displacement L2 at the casting depth l2 of the tip using equations 1 and 2, and calculates the cumulative horizontal displacement L of the tip, L = L0 + L1 + L2 , using equation 3.

そして、図７（ｃ）～（ｄ）に示すように、以降の貫入回数ｎ＝２～ｋ～ｎ（ｋは打設途中の任意の貫入回数）について、この打設深度ｌｎ分を貫入させる作業と、貫入させた後に停止させる作業と、打設深度毎に加速度計４，４による計測を行い、鋼製筒状体１の傾斜角度θｎ、先端部の単位貫入量当たりの水平変位量Ｌｎ及び先端部の累積水平変位量Ｌを算出する作業とを鋼製筒状体１の下端が図７（ｄ）に示す設計計画上の深さに到達するまで繰り返す。 Then, as shown in Figures 7(c) to (d), for the subsequent penetration count n = 2 to k to n (k is an arbitrary number of penetrations during casting), the following operations are repeated: penetrating to this casting depth l n , stopping after penetration, and taking measurements using accelerometers 4, 4 for each casting depth, and calculating the inclination angle θ n of the steel tubular body 1, the horizontal displacement L n per unit penetration at the tip, and the cumulative horizontal displacement L of the tip, until the lower end of the steel tubular body 1 reaches the design planned depth shown in Figure 7(d).

このように構成された本願発明では、加速度計４，４の位置における鉛直方向に対する鋼製筒状体１の絶対傾斜角θｎを算出することができ、その傾斜角に基づいて打設深度ｌｎ毎の水平変位量Ｌｎを求めることができ、さらに、打設深度ｌｎ毎の水平変位量Ｌｎを累積加算することによって鋼製筒状体１先端部の水平変位Ｌを求めることができる。 In the present invention configured in this manner, the absolute inclination angle θn of the steel tubular body 1 with respect to the vertical direction at the positions of the accelerometers 4, 4 can be calculated, and the horizontal displacement amount Ln for each pouring depth ln can be determined based on that inclination angle. Furthermore, the horizontal displacement L of the tip of the steel tubular body 1 can be determined by cumulatively adding up the horizontal displacement amounts Ln for each pouring depth ln .

尚、仮に累積水平変位量Ｌの上限変位量をプラスマイナス１０ｃｍとしたときに、図７（ａ）～（ｃ）の過程において、打設途中の任意の貫入回数ｋの位置に到達した際の計測値が上限変位量を超過していた時、又は上限変位量間近であったときには、計測対象である鋼製筒状体１を少なくとも前回計測した際の打設深さ分ｌｋ－１まで抜き上げ、変位方向と逆向きとなるよう変位制限措置を加えてから再度打設作業を行う。 Furthermore, if the upper limit of the cumulative horizontal displacement L is set to plus or minus 10 cm, and if the measurement value upon reaching any position of penetration number k during casting in the process of Figures 7(a) to (c) exceeds the upper limit of the displacement or is close to the upper limit of the displacement, the steel cylindrical body 1 to be measured is pulled out at least to the casting depth l k-1 at the time of the previous measurement, and a displacement limiting measure is applied so that the displacement direction is opposite to that, and then the casting work is performed again.

よって、本願発明では、鋼製筒状体１の打設対象位置に関わらず打設深度毎の水平変位量をリアルタイムに計測することができ、地盤４０からの抵抗や地質等の状況によって打設途中の鋼製筒状体１に傾きが生じた場合であっても、鋼製筒状体１の傾きを随時監視することができる。 Therefore, in the present invention, the horizontal displacement amount for each casting depth can be measured in real time regardless of the casting target position of the steel tubular body 1, and even if the steel tubular body 1 tilts during casting due to resistance from the ground 40, geology, or other conditions, the tilt of the steel tubular body 1 can be monitored at any time.

また、本願発明では、複数の加速度計４，４が筒軸方向に互いに間隔をおいて固定されているので、何れかの加速度計４，４が破損・故障した場合にも対応することができる。 In addition, in the present invention, since multiple accelerometers 4, 4 are fixed at intervals from each other in the axial direction of the cylinder, it is possible to respond even if any of the accelerometers 4, 4 is damaged or malfunctions.

尚、上述の実施例では、加速度計４，４を有線で水平変位量算出手段６に接続した場合について説明したが、加速度計４，４と水平変位量算出手段６とを無線で接続するようにしてもよく、その場合、保護カバー５は、加速度計４，４が設置された範囲のみに設けるようにしてもよい。 In the above embodiment, the accelerometers 4, 4 are connected to the horizontal displacement calculation means 6 by wire, but the accelerometers 4, 4 and the horizontal displacement calculation means 6 may be connected wirelessly. In that case, the protective cover 5 may be provided only in the area where the accelerometers 4, 4 are installed.

１ 鋼製筒状体
２ 傾斜計測装置
３ 加速度計取付部材
４ 加速度計
５ 保護カバー
６ 水平変位量算出手段
１０ 加速度計取付板
１１ 側板部
１２ 収容ケース
１３ ボルト
１４ ナット
１５ 接続ケーブル
２０ カバー本体
２１ 先端用保護部材
４０ 地盤
４１ 水面 REFERENCE SIGNS LIST 1 Steel cylindrical body 2 Inclination measurement device 3 Accelerometer mounting member 4 Accelerometer 5 Protective cover 6 Horizontal displacement calculation means 10 Accelerometer mounting plate 11 Side plate portion 12 Storage case 13 Bolt 14 Nut 15 Connection cable 20 Cover body 21 Tip protection member 40 Ground 41 Water surface

本発明は、鋼管矢板や鋼管杭等の鋼製筒状体を地盤に打設する際の鋼製筒状体の傾斜角を計測する鋼製筒状体の傾斜計測装置及び傾斜角計測方法に関する。 The present invention relates to a steel cylindrical body inclination measurement device and inclination angle measurement method that measures the inclination angle of a steel cylindrical body, such as a steel pipe sheet pile or a steel pipe pile, when the steel cylindrical body is driven into the ground.

鋼管杭や鋼管矢板等の鋼製筒状体を直杭として地盤に打設する際には、導材等によって鋼製筒状体を垂直に建て込んだ状態で杭打機によって鋼製筒状体の上端を打撃又は押し込むことにより地盤に貫入させるようになっている。 When driving a steel tubular body such as a steel pipe pile or steel pipe sheet pile into the ground as a straight pile, the steel tubular body is erected vertically using a guide material or the like, and then the top end of the steel tubular body is struck or pushed in by a pile driver to penetrate the ground.

しかしながら、杭打機により鋼製筒状体を地盤に対し垂直方向に打設しようとしても、地盤からの抵抗や地盤内の岩、地質等の状況によって打設途中の鋼製筒状体に傾きが生じる場合がある。 However, even if you try to drive a steel tubular body vertically into the ground using a pile driver, the steel tubular body may tilt during driving due to resistance from the ground or the rocks and geology in the ground.

その場合、傾いた状態に気づかずに打設し続けると、鋼製筒状体の傾斜が進み、既製杭（鋼管杭やコンクリート杭）の打設に関する一般的な管理基準で定められた許容範囲、詳しくは、平面的に見た場合の偏心量が杭径の１／４且つ１００ｍｍ以下、杭の傾斜が１／１００以下という許容範囲を超えてしまうおそれがある。 In this case, if driving continues without noticing the tilted state, the steel tubular body will continue to tilt, and there is a risk that it will exceed the allowable range set by the general management standards for driving prefabricated piles (steel pipe piles and concrete piles), specifically, the amount of eccentricity when viewed from a plan view must be 1/4 of the pile diameter and 100 mm or less, and the inclination of the pile must be 1/100 or less.

よって、このような鋼製筒状体の打設においては、打設途中における鋼製筒状体の傾きを随時監視する必要がある。 Therefore, when casting such a steel tubular body, it is necessary to constantly monitor the inclination of the steel tubular body during casting.

従来では、例えば、打設する鋼製筒状体から一定の距離をおいて複数の光学式水準器を設置し、水準器で鋼製筒状体の上端部を計測して鋼製筒状体の傾きを監視する方法等や鋼管杭の上端部に傾斜計を設置し、鋼製筒状体の傾斜を計測する方法（例えば、特許文献１を参照）等が知られている。 Conventionally, for example, methods have been known in which multiple optical levels are placed at a fixed distance from the steel tubular body to be cast, and the levels are used to measure the upper end of the steel tubular body to monitor its inclination, or a method has been known in which an inclinometer is placed at the upper end of a steel pipe pile to measure the inclination of the steel tubular body (see, for example, Patent Document 1).

特開平１－３９５１５号公報Japanese Patent Application Laid-Open No. 1-39515

しかしながら、上述の如き従来の水準器を使用した監視方法では、打設位置から離れた位置に設置した水準器により作業員が目視で観察するため、作業が煩雑であるという問題があった。 However, the above-mentioned conventional monitoring method using a level has the problem that the worker must visually observe the concrete pouring position using a level installed at a position away from the pouring position, making the work complicated.

また、鋼製筒状体の打設地点が水底である場合等では、監視位置が水上になるため、打設地点の近辺に陸が無ければ水準器を船舶上に設置しなければならず、船舶上に設置された水準器では、水面のうねり等によって正確な計測ができず、水準器での監視が困難であるという問題もあった。 In addition, when the steel cylindrical body is cast at the bottom of the water, the monitoring position is above water, and if there is no land near the casting point, a spirit level must be installed on a ship. However, a spirit level installed on a ship cannot take accurate measurements due to swells on the water surface, making monitoring with the spirit level difficult.

さらに、上述の如き従来の技術では、一定距離を隔てた位置での測定となるので、天候によっては視認が遮られ、リアルタイムで鋼製筒状体の傾きを把握することができないという問題があった。 Furthermore, with the conventional technology described above, measurements are taken at a fixed distance away, so visibility can be blocked depending on the weather, making it impossible to grasp the inclination of the steel cylindrical body in real time.

また、従来の傾斜計を用いる方法では、傾斜計を鋼製筒状体の上部に取り付けるため、地盤に打設された部分の傾斜状態を十分に把握できないという問題があった。 In addition, the conventional method using an inclinometer requires attaching the inclinometer to the top of a steel cylindrical body, which means that it is difficult to fully grasp the inclination state of the part that is cast into the ground.

そこで、本発明は、このような従来の問題に鑑み、簡便に鋼管や鋼管矢板等の傾斜をリアルタイムで正確に監視することができる鋼製筒状体の傾斜計測装置及び傾斜角計測方法の提供を目的としてなされたものである。 In view of these conventional problems, the present invention aims to provide an inclination measurement device and an inclination angle measurement method for steel cylindrical bodies that can easily and accurately monitor the inclination of steel pipes, steel pipe sheet piles, etc. in real time.

上述の如き従来の問題を解決するための請求項1に記載の発明の特徴は、打撃又は押し込むことにより地盤に打設される鋼製筒状体の傾斜を計測する鋼製筒状体の傾斜計測装置において、前記鋼製筒状体の下端より基準位置である所定の高さ位置の内周面に加速度計取付部材を介して固定された３軸加速度計からなる加速度計と、前記鋼製筒状体の内周面に固定され、前記加速度計取付部材に保持された前記加速度計を覆う保護カバーと、前記加速度計の計測データに基づき所定の打設深度だけ打設する毎に前記鋼製筒状体の前記基準位置における傾斜角と累積水平方向変位量を算出する水平変位量算出手段とを備えていることにある。 The feature of the invention described in claim 1 for solving the above-mentioned conventional problems is that, in a steel tubular body inclination measurement device that measures the inclination of a steel tubular body that is driven into the ground by striking or pushing it, it is equipped with an accelerometer consisting of a three-axis accelerometer fixed via an accelerometer mounting member to the inner surface of the steel tubular body at a predetermined height position that is a reference position from the lower end of the steel tubular body, a protective cover that is fixed to the inner surface of the steel tubular body and covers the accelerometer held by the accelerometer mounting member, and a horizontal displacement calculation means that calculates the inclination angle and accumulated horizontal displacement of the steel tubular body at the reference position each time it is cast to a predetermined casting depth based on the measurement data of the accelerometer.

請求項２に記載の発明の特徴は、請求項１の構成に加え、複数の前記加速度計が筒軸方向に互いに間隔をおいて固定されていることにある。 The invention described in claim 2 is characterized in that, in addition to the configuration of claim 1, the multiple accelerometers are fixed at intervals from each other in the cylindrical axis direction.

請求項３に記載の発明の特徴は、請求項１又は２の構成に加え、前記保護カバーは、前記鋼製筒状体の上端まで連続し、下端部が閉鎖されていることにある。 The invention described in claim 3 is characterized in that, in addition to the configuration of claim 1 or 2, the protective cover is continuous to the upper end of the steel cylindrical body and the lower end is closed.

請求項４に記載の発明の特徴は、打撃又は押し込むことにより地盤に打設される鋼製筒状体の傾斜を計測する鋼製筒状体の傾斜角計測方法において、前記鋼製筒状体の下端より所定の高さ位置の内周面に加速度計取付部材を介して３軸加速度計からなる加速度計を固定しておき、所定の打設深度だけ打設する毎に前記加速度計によって前記鋼製筒状体の傾斜角を計測し、該計測された傾斜角と該計測時の打設深度に基づき前記鋼製筒状体の基準位置における累積水平方向変位を算出することにある。 The feature of the invention described in claim 4 is that in a method for measuring the inclination angle of a steel tubular body, which measures the inclination of a steel tubular body that is driven into the ground by striking or pushing it, an accelerometer consisting of a three-axis accelerometer is fixed to the inner surface of the steel tubular body at a predetermined height position from the lower end thereof via an accelerometer mounting member, and the inclination angle of the steel tubular body is measured using the accelerometer each time it is cast to a predetermined casting depth , and a cumulative horizontal displacement at a reference position of the steel tubular body is calculated based on the measured inclination angle and the casting depth at the time of measurement .

本発明に係る鋼製筒状体の傾斜計測装置は、請求項１に記載の構成を具備することによって、簡便な構造で鋼管や鋼管矢板等の傾斜をリアルタイムで監視することができる。 The inclination measurement device for a steel cylindrical body according to the present invention has the configuration described in claim 1, and can monitor the inclination of steel pipes, steel pipe sheet piles, etc. in real time with a simple structure.

また、本発明において、請求項２に記載の構成を具備することにより、何れかの加速度計が故障や破損した場合にも計測を実行することができる。また、複数の加速度計の計測結果に基づき誤差の修正をすることができる。 In addition, by providing the configuration described in claim 2, the present invention can perform measurements even if any of the accelerometers fails or breaks. Also, errors can be corrected based on the measurement results of multiple accelerometers.

さらに、本発明において、請求項３に記載の構成を具備することによって、加速度計と地上の装置とを有線で接続することができるとともに、当該接続ケーブルを保護することができる。 Furthermore, in the present invention, by providing the configuration described in claim 3, the accelerometer and the ground device can be connected by wire, and the connection cable can be protected.

本発明に係る鋼製筒状体の傾斜計測方法は、請求項４に記載の構成を具備することによって、簡便に鋼管や鋼管矢板等の傾斜をリアルタイムで監視することができる。 The method for measuring the inclination of a steel cylindrical body according to the present invention has the configuration described in claim 4, making it possible to easily monitor the inclination of steel pipes, steel pipe sheet piles, etc. in real time.

（ａ）本発明に係る構成筒状体の傾斜計測装置の実施例を示す平面図、（ｂ）は同Ａ－Ａ線矢視断面図である。FIG. 2A is a plan view showing an embodiment of the inclination measurement device for a cylindrical body according to the present invention, and FIG. 2B is a cross-sectional view taken along line AA of the same. 図１中の加速度計の取り付け部分を示す拡大断面図である。FIG. 2 is an enlarged cross-sectional view showing a mounting portion of an accelerometer in FIG. 1 . 図２中に示すＢ－Ｂ線矢視拡大断面図である。3 is an enlarged cross-sectional view taken along line BB in FIG. 2. 図３中に示すＣ－Ｃ線矢視断面図である。4 is a cross-sectional view taken along the line CC in FIG. 3. （ａ）は図１（ａ）中の保護カバー下端部分を示す正面図、（ｂ）は同側面図である。1A is a front view showing a lower end portion of the protective cover in FIG. 1A, and FIG. 本発明の計測原理を説明するための概略断面図である。FIG. 2 is a schematic cross-sectional view for explaining the measurement principle of the present invention. （ａ）～（ｄ）は本発明に係る鋼製筒状体の傾斜計測方法の手順を示す概略断面図である。5A to 5D are schematic cross-sectional views showing the steps of the method for measuring the inclination of a steel cylindrical body according to the present invention.

次に、本発明に係る構成筒状体の傾斜計測装置２の実施態様を図１～図６に示した実施例に基づいて説明する。尚、図中符号１は鋼管杭や鋼管矢板等の鋼製筒状体である。 Next, an embodiment of the inclination measurement device 2 for a cylindrical body according to the present invention will be described based on the examples shown in Figures 1 to 6. In the figures, reference numeral 1 denotes a steel cylindrical body such as a steel pipe pile or a steel pipe sheet pile.

鋼製筒状体１は、鋼管杭や鋼管矢板等の鋼製の上下端が開口した一定長さを有する筒状に形成され、バイブロハンマや杭打機等によって打撃又は押し込むことにより地盤４０に打設されるようになっている。 The steel tubular body 1 is made of steel, such as a steel pipe pile or steel pipe sheet pile, and is formed into a cylindrical shape of a certain length with open top and bottom ends, and is designed to be driven into the ground 40 by striking or pushing it with a vibro hammer, pile driver, etc.

尚、鋼製筒状体１は、図１に示す円筒状に限定されず、角筒状や多角形筒状であってもよい。 The steel tubular body 1 is not limited to the cylindrical shape shown in FIG. 1, but may be a square or polygonal tubular shape.

この鋼製筒状体１は、導材等によって垂直に建て込んだ状態で杭打機等によって鋼製筒状体１の上端を打撃又は押し込むことにより地盤４０に貫入させるようになっている。 This steel tubular body 1 is erected vertically using conductors or the like, and then penetrated into the ground 40 by striking or pushing the upper end of the steel tubular body 1 with a pile driver or the like.

その際、鋼製筒状体１は、傾斜計測装置２によって打設途中における鋼製筒状体１の傾きが随時監視できるようになっている。 At this time, the inclination of the steel cylindrical body 1 during casting can be monitored at any time by the inclination measuring device 2.

この傾斜計測装置２は、図１に示すように、鋼製筒状体１の下端より所定の距離をおいた基準位置である所定の高さ位置の内周面に加速度計取付部材３を介して固定された加速度計４，４と、鋼製筒状体１の内周面に固定され、加速度計取付部材３に保持された加速度計４，４を覆う保護カバー５と、加速度計４，４の計測データに基づき所定の打設深度ｌｎ毎に鋼製筒状体１の基準位置の水平方向変位量Ｌｎを算出する水平変位量算出手段６とを備えている。 As shown in Figure 1, this inclination measurement device 2 comprises accelerometers 4, 4 fixed via accelerometer mounting members 3 to the inner surface of the steel tubular body 1 at a predetermined height position, which is a reference position a predetermined distance from the lower end of the steel tubular body 1, a protective cover 5 fixed to the inner surface of the steel tubular body 1 and covering the accelerometers 4, 4 held by the accelerometer mounting members 3, and a horizontal displacement amount calculation means 6 which calculates the horizontal displacement amount Ln of the reference position of the steel tubular body 1 for each predetermined casting depth ln based on the measurement data of the accelerometers 4, 4.

加速度計取付部材３は、図３に示すように、平板状の加速度計取付板１０と、加速度計取付板１０の両側縁より加速度計取付板１０に対し鋼製筒状体の内周面に向け略直角方向に延出した板状の側板部１１，１１とを備え、断面視コ字状に形成され、両側板部１１，１１の短手方向端縁が溶接により基準位置である所定の高さ位置で鋼製筒状内周面に固定されている。尚、この加速度計取付部材３には、一般的な溝形鋼等を用いることができる。 As shown in FIG. 3, the accelerometer mounting member 3 comprises a flat accelerometer mounting plate 10 and plate-like side plate portions 11, 11 extending from both side edges of the accelerometer mounting plate 10 in a direction approximately perpendicular to the inner peripheral surface of the steel cylindrical body, and is formed in a U-shape in cross section, with the short end edges of both side plate portions 11, 11 fixed to the inner peripheral surface of the steel cylindrical body at a predetermined height position, which is the reference position, by welding. Note that general channel steel or the like can be used for this accelerometer mounting member 3.

加速度計取付部材３は、図２に示すように、少なくとも一つが鋼製筒状体１の下端より基準位置である所定の高さ位置の鋼製筒状体１の内周面に長手方向を筒軸方向に向けて固定され、その他の加速度計取付部材３，３がそれぞれ筒軸方向で連続する配置に固定され、複数（少なくとも二つ）の加速度計４，４が筒軸方向に所定の間隔をおいて連続的に配置されるようになっている。 As shown in FIG. 2, at least one accelerometer mounting member 3 is fixed to the inner surface of the steel cylindrical body 1 at a predetermined height position, which is a reference position from the lower end of the steel cylindrical body 1, with its longitudinal direction facing the cylindrical axis direction, and the other accelerometer mounting members 3, 3 are fixed in a continuous arrangement in the cylindrical axis direction, so that multiple (at least two) accelerometers 4, 4 are continuously arranged at a predetermined interval in the cylindrical axis direction.

尚、本実施形態においては、鋼製筒状体１の下端部の打設時の状態を考慮し、鋼製筒状体１の下端より略１ｍ上方を基準位置として設定しているが、杭先端部の状況予測によっては、より下方に設けてもよい。 In this embodiment, the reference position is set approximately 1 m above the bottom end of the steel tubular body 1, taking into consideration the condition of the bottom end of the steel tubular body 1 when it is cast, but it may be set lower depending on the predicted condition of the tip of the pile.

また、もう一つ取り付ける加速度計４は、基準位置に設置した加速度計４が打設に伴い破損した場合のバックアップ用として設置することから、加速度計４が取り付けられた基準位置からの間隔はあまり長くせず、１ｍ程度が望ましい。 The other accelerometer 4 is installed as a backup in case the accelerometer 4 installed at the reference position is damaged during concrete pouring, so the distance from the reference position to the accelerometer 4 should not be too long, preferably about 1 m.

各加速度計取付部材３には、図２～４に示すように、加速度計取付板１０の表面側にボルト締め等によって収容ケース１２が固定され、収容ケース１２を介して加速度計４，４が固定されるようになっている。 As shown in Figures 2 to 4, each accelerometer mounting member 3 has a housing case 12 fixed to the front side of the accelerometer mounting plate 10 by bolting or the like, and the accelerometers 4, 4 are fixed via the housing case 12.

収容ケース１２は、細板状の底板１２ａと、底板１２ａの短辺の両端部上に立ち上げた端壁部１２ｂ，１２ｂと、底板１２ａの長辺の両端部上に立ち上げた側壁部１２ｃ，１２ｃと、底板１２ａの底面部と加速度計取付板１０の表面との間に配置され、収容ケース１２の長辺方向に間隔をおいて固定された複数の取付板１２ｄ，１２ｄ…とを備え、各取付板１２ｄ，１２ｄ…のボルト挿通孔１２ｅ，１２ｅを対応する加速度計取付板１０のボルト挿通孔１０ａ，１０ａの位置に合わせ、取付板１２ｄを貫通させたボルト１３に加速度計取付板１０の裏面側からナット１４を螺合させることによって固定されている。 The storage case 12 comprises a thin bottom plate 12a, end walls 12b, 12b raised on both ends of the short side of the bottom plate 12a, side walls 12c, 12c raised on both ends of the long side of the bottom plate 12a, and a number of mounting plates 12d, 12d... arranged between the bottom surface of the bottom plate 12a and the surface of the accelerometer mounting plate 10 and fixed at intervals in the long side direction of the storage case 12. The bolt insertion holes 12e, 12e of each mounting plate 12d, 12d... are aligned with the corresponding bolt insertion holes 10a, 10a of the accelerometer mounting plate 10, and the bolts 13 that pass through the mounting plate 12d are fixed by screwing nuts 14 from the back side of the accelerometer mounting plate 10.

加速度計４，４は、少なくとも２つの圧電性結晶がそれぞれ別々の軸の振動に反応するように配置され、ｘ、ｙ、ｚ方向の３軸の振動に基づき各軸の加速度を計測する３軸加速度計で構成され、有線で水平変位量算出手段６と接続されている。尚、図中符号１５は加速度計４への電源供給及び加速度計４の計測データを送信するための接続ケーブル１５であって、この接続ケール１５が加速度計４本体と水平変位量算出手段６とを接続している。 The accelerometers 4, 4 are configured as three-axis accelerometers in which at least two piezoelectric crystals are arranged so that they respond to vibrations along different axes, and which measure the acceleration along each axis based on vibrations along three axes in the x, y, and z directions, and are connected to the horizontal displacement calculation means 6 by wire. Note that reference numeral 15 in the figure denotes a connection cable 15 for supplying power to the accelerometer 4 and transmitting the measurement data of the accelerometer 4, and this connection cable 15 connects the accelerometer 4 main body to the horizontal displacement calculation means 6.

加速度計４，４は、図４に示すように、収容ケース１２に収容され、ｘ軸を筒軸方向に、ｚ軸を管径方向にそれぞれ向けられるよう、収容ケース１２を介して加速度計取付部材３に固定されている。 As shown in FIG. 4, the accelerometers 4, 4 are housed in a housing case 12 and fixed to the accelerometer mounting member 3 via the housing case 12 so that the x-axis is oriented in the tube axis direction and the z-axis is oriented in the tube diameter direction.

また、加速度計４，４は、接続ケーブル１５の一部とともに収容ケース１２に収められ、収容ケース１２内に充填された樹脂材によって収容ケース１２に固定されている。 The accelerometers 4, 4 are housed in the housing case 12 together with a portion of the connection cable 15, and are fixed to the housing case 12 by a resin material filled in the housing case 12.

接続ケーブル１５は、収容ケース１２の上端開口部より引き出され、鋼製筒状体１の内周面に沿って鋼製筒状体１の上端開口部まで引き出され、鋼製筒状体１の上端部切り欠け又は上部側面の孔から水平変位量算出手段６に接続されている。 The connection cable 15 is pulled out from the upper opening of the storage case 12, pulled along the inner surface of the steel cylindrical body 1 to the upper opening of the steel cylindrical body 1, and connected to the horizontal displacement calculation means 6 through the notch at the upper end of the steel cylindrical body 1 or a hole in the upper side surface.

尚、接続ケーブル１５は、特に図示しないが、鋼製筒状体１の内周面に固定具によって固定されている。 Although not specifically shown, the connection cable 15 is fixed to the inner surface of the steel cylindrical body 1 by a fastener.

保護カバー５は、加速度計４，４及び加速度計取付部材３を覆うカバー本体２０と、カバー本体２０の下端部を閉鎖する先端用保護部材２１とを備え、鋼製筒状体１の下端より軸方向に所定の距離をおいた位置から上端部まで連続して鋼製筒状体１の内周面に固定されている。 The protective cover 5 comprises a cover body 20 that covers the accelerometers 4, 4 and the accelerometer mounting member 3, and a tip protective member 21 that closes the lower end of the cover body 20, and is fixed to the inner surface of the steel cylindrical body 1 continuously from a position that is a predetermined distance in the axial direction from the lower end of the steel cylindrical body 1 to the upper end.

カバー本体２０は、図３に示すように、細板状の天板２０ａと、天板２０ａの短辺両側縁より天板２０ａに対し鋼製筒状体１の内周面に向けて略直角方向に延出した板状の側板２０ｂ，２０ｂとを備え、平面視コ字状に形成され、両側板２０ｂ，２０ｂの短手方向端縁が溶接により鋼製筒状体１の内周面に固定されている。 As shown in FIG. 3, the cover body 20 is formed in a U-shape in a plan view and includes a thin top plate 20a and plate-like side plates 20b, 20b that extend from both short side edges of the top plate 20a toward the inner peripheral surface of the steel cylindrical body 1 at approximately right angles to the top plate 20a. The short side edges of both side plates 20b, 20b are fixed to the inner peripheral surface of the steel cylindrical body 1 by welding.

カバー本体２０は、天板２０ａの幅が加速度計取付部材３の幅よりも十分に幅広に形成されるとともに、両側板２０ｂ，２０ｂの幅（鋼製筒状体１内周面からの突出高さ）が天板２０ａと加速度計取付部材３に収容ケース１２を介して固定された加速度計４，４との間に一定の隙間が形成される幅に形成されている。 The cover body 20 is formed so that the width of the top plate 20a is sufficiently wider than the width of the accelerometer mounting member 3, and the width of both side plates 20b, 20b (protruding height from the inner peripheral surface of the steel cylindrical body 1) is such that a certain gap is formed between the top plate 20a and the accelerometers 4, 4 fixed to the accelerometer mounting member 3 via the housing case 12.

先端用保護部材２１は、図５に示すように、カバー本体２０の下端部の外周に沿って嵌合される断面視コ字状の嵌合部２１ａと、嵌合部２１ａの下端より下方外側（鋼製筒状体１内周面側）に傾斜した傾斜板２１ｂと、傾斜板２１ｂの両側部を塞ぐために配置された直角三角形状の両傾斜側板２１ｃ，２１ｃと、両傾斜側板２１ｃ，２１ｃ間に間隔をおいて配置された補強リブ２１ｄ，２１ｄとを備え、カバー本体２０の下端に嵌合され、カバー本体２０の下端を閉鎖している。 As shown in FIG. 5, the tip protection member 21 is fitted to the lower end of the cover body 20 along the outer periphery of the lower end of the cover body 20 and has a U-shaped fitting portion 21a in cross section, an inclined plate 21b inclined downward and outward (toward the inner periphery of the steel cylindrical body 1) from the lower end of the fitting portion 21a, two inclined side plates 21c, 21c in the shape of a right triangle arranged to close both sides of the inclined plate 21b, and reinforcing ribs 21d, 21d arranged at intervals between the two inclined side plates 21c, 21c. The tip protection member 21 is fitted to the lower end of the cover body 20 and closes the lower end of the cover body 20.

傾斜板２１ｂは、先端側に円弧状の掘削刃２１ｅが形成され、掘削刃２１ｅで地盤４０が掘削されることにより、先端用保護部材２１及びカバー本体２０が地盤４０に貫入される際の抵抗が軽減されている。 The inclined plate 21b has an arc-shaped excavation blade 21e formed on the tip side, and the excavation blade 21e excavates the ground 40, reducing resistance when the tip protection member 21 and the cover body 20 penetrate the ground 40.

水平変位量算出手段６は、パーソナルコンピュータ、タブレット端末等のコンピュータ機器に搭載されたプログラムよって構成され、加速度計４，４から出力されるデータを基に以下の式１～３により鋼製筒状体１の傾斜角θｎ、基準位置の水平方向変位量Ｌｎ及び加速度計４が設置されている先端部の累積水平変位量Ｌを算出するようになっている。尚、Ｋｘは加速度計４，４のｘ方向（筒軸方向）出力値（ｍ／ｓ２）、Ｋｚは加速度計４，４のｚ方向（管径方向）出力値（ｍ／ｓ２）、θｎは矢板の傾斜角、Ｇは重力加速度（ｍ／ｓ２）である。
（数式１）
θｎ＝ｔａｎ－１（Ｋｘ／Ｋｚ）
（数式２)
Ｌｎ＝ｌｎ×ｔａｎθｎ
（数式３）
Ｌ＝Ｌ０＋Ｌ１＋…＋Ｌｎ The horizontal displacement calculation means 6 is configured by a program installed in a computer device such as a personal computer or a tablet terminal, and is configured to calculate the inclination angle θn of the steel cylindrical body 1, the horizontal displacement Ln of the reference position, and the accumulated horizontal displacement L of the tip where the accelerometer 4 is installed, using the following equations 1 to 3 based on the data output from the accelerometers 4, 4. Note that Kx is the x-direction (cylinder axis direction) output value (m/s 2 ) of the accelerometers 4, 4, Kz is the z-direction (pipe diameter direction) output value (m/s 2 ) of the accelerometers 4, 4, θn is the inclination angle of the sheet pile, and G is the gravitational acceleration (m/s 2 ).
(Formula 1)
θ n =tan −1 (K x /K z )
(Formula 2)
Ln = ln × tan θn
(Formula 3)
L = L 0 + L 1 + ... + L n

尚、水平変位量算出手段６は、鋼製筒状体１を打設する打設船等に設置するが、加速度計４，４の計測データが無線で送信されるときには、陸上の事務所棟等に設置するようにしてもよい。 The horizontal displacement calculation means 6 is installed on a casting ship that casts the steel cylindrical body 1, but when the measurement data of the accelerometers 4, 4 is transmitted wirelessly, it may be installed in an office building on land, etc.

次に、上述の加速度計４を使用した鋼製筒状体１の傾斜計測方法について図７に基づいて説明する。尚、上述の実施例と同様の構成には同一符号を付して説明を省略する。 Next, a method for measuring the inclination of the steel cylindrical body 1 using the above-mentioned accelerometer 4 will be described with reference to FIG. 7. Note that the same components as those in the above-mentioned embodiment are given the same reference numerals and will not be described.

先ず、事前準備として、地上の工場や製作ヤードにおいて、打設する鋼管杭や鋼管矢板等の鋼製筒状体１の内側面の所定の位置に加速度計取付部材３を溶接等によって取り付け、加速度計取付部材３に収容ケース１２に収容された加速度計４，４を固定する。 First, as a preliminary preparation, in an above-ground factory or production yard, the accelerometer mounting member 3 is attached by welding or the like to a predetermined position on the inside surface of the steel cylindrical body 1, such as a steel pipe pile or steel pipe sheet pile, to be driven, and the accelerometers 4, 4 housed in the housing case 12 are fixed to the accelerometer mounting member 3.

また、各加速度計４，４本体から引き出された接続ケーブル１５を鋼製筒状体１の内周面軸方向に沿って這わせ、端部を鋼製筒状体１の上端開口部まで引き出しておく。尚、接続ケーブル１５は、鋼製筒状体１の上部開口部近くに設けた孔を通して鋼製筒状体１の外部に引き出すようにしてもよい。 The connection cables 15 pulled out from the main bodies of the accelerometers 4, 4 are laid along the axial direction of the inner periphery of the steel cylindrical body 1, and the ends are pulled out to the upper opening of the steel cylindrical body 1. The connection cables 15 may also be pulled out to the outside of the steel cylindrical body 1 through a hole provided near the upper opening of the steel cylindrical body 1.

そして、加速度計４，４の設置が完了したら、保護カバー５を加速度計取付部材３に収容ケース１２を介して取り付けられた加速度計４，４及び接続ケーブル１５を覆うように鋼製筒状体１の内周面に溶接によって固定する。また、保護カバー５の下端部に先端用保護部材２１を取り付ける。 After the installation of the accelerometers 4, 4 is completed, the protective cover 5 is fixed by welding to the inner surface of the steel cylindrical body 1 so as to cover the accelerometers 4, 4 and the connection cable 15 attached to the accelerometer mounting member 3 via the housing case 12. In addition, a tip protective member 21 is attached to the lower end of the protective cover 5.

次に、具体的な鋼製筒状体１の傾斜計測方法について説明する。 Next, we will explain a specific method for measuring the inclination of the steel cylindrical body 1.

先ず、図７（ａ）に示すように、鋼製筒状体１を測量により鉛直性を確保しつつ、下端部を一定深さ（以下、建て込み深さｌ０という）だけ地盤４０に貫入させた状態に建て込む。尚、図中符号４１は水面である。 First, as shown in Fig. 7(a), the steel cylindrical body 1 is erected with its lower end penetrating a certain depth (hereinafter referred to as the erection depth l0 ) into the ground 40 while ensuring its verticality by surveying. In the figure, the reference numeral 41 denotes the water surface.

そして、加速度計４，４による出力を開始し、出力された計測データに基づき水平変位量算出手段６が建て込み深さｌ０における鋼製筒状体１の傾斜角度（以下、初期傾斜角θ０という）及び先端部の水平変位量Ｌ０を上述した式１及び式２により算出する。 Then, output from the accelerometers 4, 4 is started, and based on the output measurement data, the horizontal displacement calculation means 6 calculates the inclination angle of the steel cylindrical body 1 at the erection depth l 0 (hereinafter referred to as the initial inclination angle θ 0 ) and the horizontal displacement amount L 0 of the tip portion using the above-mentioned equations 1 and 2.

尚、初期傾斜角θ０及び先端部の水平変位量Ｌ０の算出は、加速度計４，４による計測を１秒間に複数回行い、その平均値を測定値として行う。 The initial tilt angle θ 0 and the horizontal displacement amount L 0 of the tip are calculated by performing measurements by the accelerometers 4, 4 multiple times per second and averaging the measurements.

次に、鋼製筒状体１の打設を開始し、図７（ｂ）に示すように、建て込み深さより所定の深さ分ｌ１だけバイブロハンマや杭打機により鋼製筒状体１の上端を打撃又は押込み、鋼製筒状体１を所定の打設深度まで地盤４０に貫入させる。 Next, the casting of the steel tubular body 1 is started, and as shown in Figure 7 (b), the upper end of the steel tubular body 1 is struck or pushed in by a vibro hammer or pile driver to a predetermined depth l1 from the erection depth, so that the steel tubular body 1 penetrates into the ground 40 to the predetermined casting depth.

鋼製筒状体１を打設深度ｌ１だけ地盤４０に貫入させたら、一旦打設作業を停止し、振動が無い状態で加速度計４，４による計測を行い、出力された計測データに基づき水平変位量算出手段６が打設深度ｌ１における鋼製筒状体１の傾斜角度θ１及び先端部の単位貫入量当たりの水平変位量Ｌ１を式１及び式２により算出し、先端部の累積水平変位量Ｌ＝Ｌ０＋Ｌ１を式３により算出する。 Once the steel tubular body 1 has been penetrated into the ground 40 to a casting depth l1 , the casting work is stopped for a moment and measurements are taken using the accelerometers 4, 4 in an absence of vibration. Based on the output measurement data, the horizontal displacement calculation means 6 calculates the inclination angle θ1 of the steel tubular body 1 at the casting depth l1 and the horizontal displacement L1 per unit penetration at the tip using equations 1 and 2, and calculates the cumulative horizontal displacement L = L0 + L1 at the tip using equation 3.

尚、傾斜角θ１及び単位貫入量当たりの先端部の水平変位量Ｌ１の算出は、加速度計４，４による計測を１秒間に複数回行い、その平均値を測定値として行う。 The inclination angle θ1 and the horizontal displacement L1 of the tip per unit penetration are calculated by performing measurements with the accelerometers 4, 4 multiple times per second and averaging the measurements.

次に、鋼製筒状体１の打設を再開し、現位置から所定の深さ分ｌ２だけバイブロハンマや杭打機により鋼製筒状体１の上端を打撃又は押込み、鋼製筒状体１をさらに地盤４０に貫入させる。 Next, casting of the steel cylindrical body 1 is resumed, and the upper end of the steel cylindrical body 1 is struck or pushed in a predetermined depth l2 from the current position using a vibro hammer or pile driver, thereby penetrating the steel cylindrical body 1 further into the ground 40.

そして、鋼製筒状体１を打設深度ｌ2だけ地盤４０に貫入させたら、再度打設作業を停止し、振動が無い状態で加速度計４，４による計測を行い、出力された計測データに基づき水平変位量算出手段６が打設深度ｌ2分を貫入させた際の鋼製筒状体１の傾斜角度θ2及び先端部の打設深度ｌ2の水平変位量Ｌ2を式１及び式２により算出し、先端部の累積水平変位量Ｌ＝Ｌ０＋Ｌ１＋Ｌ２を式３により算出する。 Then, once the steel tubular body 1 has been penetrated into the ground 40 by a casting depth l2 , the casting work is stopped again and measurements are taken using the accelerometers 4, 4 in an absence of vibration. Based on the output measurement data, the horizontal displacement calculation means 6 calculates the inclination angle θ2 of the steel tubular body 1 when it has been penetrated by casting depth l2 and the horizontal displacement L2 at the casting depth l2 of the tip using equations 1 and 2, and calculates the cumulative horizontal displacement L of the tip, L = L0 + L1 + L2 , using equation 3.

そして、図７（ｃ）～（ｄ）に示すように、以降の貫入回数ｎ＝２～ｋ～ｎ（ｋは打設途中の任意の貫入回数）について、この打設深度ｌｎ分を貫入させる作業と、貫入させた後に停止させる作業と、打設深度毎に加速度計４，４による計測を行い、鋼製筒状体１の傾斜角度θｎ、先端部の単位貫入量当たりの水平変位量Ｌｎ及び先端部の累積水平変位量Ｌを算出する作業とを鋼製筒状体１の下端が図７（ｄ）に示す設計計画上の深さに到達するまで繰り返す。 Then, as shown in Figures 7(c) to (d), for the subsequent penetration count n = 2 to k to n (k is an arbitrary number of penetrations during casting), the following operations are repeated: penetrating to this casting depth l n , stopping after penetration, and taking measurements using accelerometers 4, 4 for each casting depth, and calculating the inclination angle θ n of the steel tubular body 1, the horizontal displacement L n per unit penetration at the tip, and the cumulative horizontal displacement L of the tip, until the lower end of the steel tubular body 1 reaches the design planned depth shown in Figure 7(d).

このように構成された本願発明では、加速度計４，４の位置における鉛直方向に対する鋼製筒状体１の絶対傾斜角θｎを算出することができ、その傾斜角に基づいて打設深度ｌｎ毎の水平変位量Ｌｎを求めることができ、さらに、打設深度ｌｎ毎の水平変位量Ｌｎを累積加算することによって鋼製筒状体１先端部の水平変位Ｌを求めることができる。 In the present invention configured in this manner, the absolute inclination angle θn of the steel tubular body 1 with respect to the vertical direction at the positions of the accelerometers 4, 4 can be calculated, and the horizontal displacement amount Ln for each pouring depth ln can be obtained based on that inclination angle. Furthermore, the horizontal displacement L of the tip of the steel tubular body 1 can be obtained by cumulatively adding up the horizontal displacement amounts Ln for each pouring depth ln .

尚、仮に累積水平変位量Ｌの上限変位量をプラスマイナス１０ｃｍとしたときに、図７（ａ）～（ｃ）の過程において、打設途中の任意の貫入回数ｋの位置に到達した際の計測値が上限変位量を超過していた時、又は上限変位量間近であったときには、計測対象である鋼製筒状体１を少なくとも前回計測した際の打設深さ分ｌｋ－１まで抜き上げ、変位方向と逆向きとなるよう変位制限措置を加えてから再度打設作業を行う。 Furthermore, if the upper limit of the cumulative horizontal displacement L is set to plus or minus 10 cm, and if the measurement value upon reaching any position of penetration number k during casting in the process of Figures 7(a) to (c) exceeds the upper limit of the displacement or is close to the upper limit of the displacement, the steel cylindrical body 1 to be measured is pulled out at least to the casting depth l k-1 at the time of the previous measurement, and a displacement limiting measure is applied so that the displacement direction is opposite to that, and then the casting work is performed again.

よって、本願発明では、鋼製筒状体１の打設対象位置に関わらず打設深度毎の水平変位量をリアルタイムに計測することができ、地盤４０からの抵抗や地質等の状況によって打設途中の鋼製筒状体１に傾きが生じた場合であっても、鋼製筒状体１の傾きを随時監視することができる。 Therefore, in the present invention, the horizontal displacement amount for each casting depth can be measured in real time regardless of the casting target position of the steel tubular body 1, and even if the steel tubular body 1 tilts during casting due to resistance from the ground 40, geology, or other conditions, the tilt of the steel tubular body 1 can be monitored at any time.

また、本願発明では、複数の加速度計４，４が筒軸方向に互いに間隔をおいて固定されているので、何れかの加速度計４，４が破損・故障した場合にも対応することができる。 In addition, in the present invention, since multiple accelerometers 4, 4 are fixed at intervals from each other in the axial direction of the cylinder, it is possible to respond even if any of the accelerometers 4, 4 is damaged or malfunctions.

尚、上述の実施例では、加速度計４，４を有線で水平変位量算出手段６に接続した場合について説明したが、加速度計４，４と水平変位量算出手段６とを無線で接続するようにしてもよく、その場合、保護カバー５は、加速度計４，４が設置された範囲のみに設けるようにしてもよい。 In the above embodiment, the accelerometers 4, 4 are connected to the horizontal displacement calculation means 6 by wire, but the accelerometers 4, 4 and the horizontal displacement calculation means 6 may be connected wirelessly. In that case, the protective cover 5 may be provided only in the area where the accelerometers 4, 4 are installed.

１ 鋼製筒状体
２ 傾斜計測装置
３ 加速度計取付部材
４ 加速度計
５ 保護カバー
６ 水平変位量算出手段
１０ 加速度計取付板
１１ 側板部
１２ 収容ケース
１３ ボルト
１４ ナット
１５ 接続ケーブル
２０ カバー本体
２１ 先端用保護部材
４０ 地盤
４１ 水面 REFERENCE SIGNS LIST 1 Steel cylindrical body 2 Inclination measurement device 3 Accelerometer mounting member 4 Accelerometer 5 Protective cover 6 Horizontal displacement calculation means 10 Accelerometer mounting plate 11 Side plate portion 12 Storage case 13 Bolt 14 Nut 15 Connection cable 20 Cover body 21 Tip protection member 40 Ground 41 Water surface

Claims (4)

打撃又は押し込むことにより地盤に打設される鋼製筒状体の傾斜を計測する鋼製筒状体の傾斜計測装置において、
前記鋼製筒状体の下端より基準位置である所定の高さ位置の内周面に加速度計取付部材を介して固定された加速度計と、前記鋼製筒状体の内周面に固定され、前記加速度計取付部材に保持された前記加速度計を覆う保護カバーと、前記加速度計の計測データに基づき所定の打設深度毎に前記鋼製筒状体の前記基準位置の水平方向変位量を算出する水平変位量算出手段とを備えていることを特徴とする鋼製筒状体の傾斜計測装置。 A steel cylindrical body inclination measurement device that measures the inclination of a steel cylindrical body that is driven into the ground by striking or pushing it,
This device for measuring the inclination of a steel cylindrical body is characterized by comprising an accelerometer fixed to the inner surface of the steel cylindrical body at a predetermined height position above the lower end of the steel cylindrical body via an accelerometer mounting member, a protective cover fixed to the inner surface of the steel cylindrical body and covering the accelerometer held by the accelerometer mounting member, and a horizontal displacement calculation means for calculating the horizontal displacement of the reference position of the steel cylindrical body for each predetermined casting depth based on the measurement data of the accelerometer. 複数の前記加速度計が筒軸方向に互いに間隔をおいて固定されている請求項１に記載の鋼製筒状体の傾斜計測装置。 The tilt measurement device for a steel cylindrical body according to claim 1, in which a plurality of the accelerometers are fixed at intervals in the axial direction of the cylinder. 前記保護カバーは、前記鋼製筒状体の上端まで連続し、下端部が閉鎖されている請求項１又は２に記載の鋼製筒状体の傾斜計測装置。 The tilt measuring device for a steel cylindrical body according to claim 1 or 2, wherein the protective cover is continuous to the upper end of the steel cylindrical body and the lower end is closed. 打撃又は押し込むことにより地盤に打設される鋼製筒状体の傾斜を計測する鋼製筒状体の傾斜計測方法において、
前記鋼製筒状体の下端より所定の高さ位置の内周面に加速度計取付部材を介して加速度計を固定しておき、
所定の打設深度毎に前記加速度計によって前記鋼製筒状体の傾斜角を計測し、該計測された傾斜角と打設深度に基づき前記鋼製筒状体の基準位置における水平方向変位を算出することを特徴とする鋼製筒状体の傾斜計測方法。 A method for measuring the inclination of a steel cylindrical body, which measures the inclination of a steel cylindrical body that is driven into the ground by striking or pushing the steel cylindrical body, comprising:
An accelerometer is fixed to the inner peripheral surface of the steel cylindrical body at a predetermined height from the lower end thereof via an accelerometer mounting member;
A method for measuring the inclination of a steel tubular body, characterized in that the inclination angle of the steel tubular body is measured using the accelerometer for each specified casting depth, and the horizontal displacement of the steel tubular body at a reference position is calculated based on the measured inclination angle and casting depth.
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05339931A (en) * 1992-06-04 1993-12-21 Kawasaki Steel Corp Bearing force analysis of pile foundation and its device
JP3036985U (en) * 1996-10-17 1997-05-06 株式会社日本技建 Pile
JP2002054131A (en) * 2000-08-11 2002-02-20 Hazama Gumi Ltd Soil improving structure and soil improving method capable of controlling peripheral ground displacement
JP2006105798A (en) * 2004-10-06 2006-04-20 Oki Electric Ind Co Ltd Semiconductor acceleration sensor and method for manufacturing same
JP2017172115A (en) * 2016-03-18 2017-09-28 前田建設工業株式会社 Ground evaluation system, precast pile with acceleration sensor

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05339931A (en) * 1992-06-04 1993-12-21 Kawasaki Steel Corp Bearing force analysis of pile foundation and its device
JP3036985U (en) * 1996-10-17 1997-05-06 株式会社日本技建 Pile
JP2002054131A (en) * 2000-08-11 2002-02-20 Hazama Gumi Ltd Soil improving structure and soil improving method capable of controlling peripheral ground displacement
JP2006105798A (en) * 2004-10-06 2006-04-20 Oki Electric Ind Co Ltd Semiconductor acceleration sensor and method for manufacturing same
JP2017172115A (en) * 2016-03-18 2017-09-28 前田建設工業株式会社 Ground evaluation system, precast pile with acceleration sensor

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