JP2013100696A - Method for managing tension of pc steel rod - Google Patents

Method for managing tension of pc steel rod Download PDF

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JP2013100696A
JP2013100696A JP2011245715A JP2011245715A JP2013100696A JP 2013100696 A JP2013100696 A JP 2013100696A JP 2011245715 A JP2011245715 A JP 2011245715A JP 2011245715 A JP2011245715 A JP 2011245715A JP 2013100696 A JP2013100696 A JP 2013100696A
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tension
nut
jack
steel rod
hydraulic jack
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JP5799762B2 (en
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Jun Nomura
潤 野村
Yoshito Mizushima
好人 水島
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Obayashi Corp
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Abstract

PROBLEM TO BE SOLVED: To accurately manage tension of a PC steel rod after tensile stress applied with a jack is released.SOLUTION: A method is to manage tension of a PC steel rod 10 in construction to fix the same in a concrete structure 1 by: fastening a nut 12 of the PC steel rod 10 in a state that the same inserted in the concrete structure 1 is put under tension with a hydraulic jack 20; and releasing the tension of the PC steel rod 10 applied with the hydraulic jack 20 with the nut 12 fastened. The method: preliminarily obtains a relation among hydraulic pressure of the hydraulic jack 20 before fastening the nut 12, an amount of decrease in the hydraulic pressure of the hydraulic jack 20 on completion of fastening the nut 12 and the tension of the PC steel rod 10 after releasing the tension applied with the hydraulic jack 20; decides, based on the relation, the hydraulic pressure before fastening the nut 12 and the amount of decrease in the hydraulic pressure of the hydraulic jack 20 on completion of fastening the nut 12; and fastens the nut 12 so that the hydraulic pressure of the hydraulic jack 20 decreases by the decided amount.

Description

本発明は、PC鋼棒の張力を管理する方法に関する。   The present invention relates to a method for managing the tension of a PC steel bar.

従来から、コンクリート構造体に挿通させたPC鋼棒を緊張させてコンクリート構造体にプレストレスを導入したり、当該PC鋼棒でコンクリート構造体とコンクリート又は鋼製の構造体とを結合したりすることが行われており、その際のPC鋼棒の張力を管理する方法が考えられている(例えば、特許文献1参照)。特許文献1に記載のPC鋼棒の緊張方法は、油圧ジャッキでPC鋼棒を緊張させた状態でPC鋼棒のナットを締付け、その後、油圧ジャッキによるPC鋼棒の緊張を開放するというものである。   Conventionally, a PC steel rod inserted through a concrete structure is tensioned to introduce prestress into the concrete structure, or a concrete structure and a concrete or steel structure are coupled with the PC steel rod. A method of managing the tension of the PC steel bar at that time is considered (for example, see Patent Document 1). The tension method of the PC steel bar described in Patent Document 1 is to tighten the nut of the PC steel bar in a state where the PC steel bar is tensioned by a hydraulic jack, and then release the tension of the PC steel bar by the hydraulic jack. is there.

また、特許文献1に記載のPC鋼棒の張力の評価方法は、PC鋼棒に超音波パルスを入射し、その反射波の伝搬時間に基づいてPC鋼棒の張力を評価するというものである。   Moreover, the evaluation method of the tension | tensile_strength of the PC steel rod of patent document 1 is that the ultrasonic pulse is incident on the PC steel rod and the tension of the PC steel rod is evaluated based on the propagation time of the reflected wave. .

特開平7−113231号公報JP-A-7-113231

特許文献1に記載のPC鋼棒の緊張方法では、油圧ジャッキによるPC鋼棒の緊張を開放した後、ナットの雌ネジとPC鋼棒の雄ネジとの隙間によるガタ(セット量)の分だけPC鋼棒の伸びが減少して張力が低下することから、PC鋼棒の張力が設計緊張力を下回ってしまう場合がある。   In the tensioning method of the PC steel rod described in Patent Document 1, after releasing the tension of the PC steel rod by the hydraulic jack, the backlash due to the gap between the female screw of the nut and the male screw of the PC steel rod (set amount) Since the elongation of the PC steel bar decreases and the tension decreases, the tension of the PC steel bar may fall below the design tension.

なお、特許文献1には、PC鋼棒の緊張時と非緊張時との反射波の伝搬時間の差に基づいてPC鋼棒の張力を評価することが開示されているが、この反射波の伝搬時間の差から如何にしてPC鋼棒の緊張力を求めるかは開示されておらず、ジャッキによる緊張を開放した後のPC鋼棒の張力を正確に管理できるには至っていない。   In addition, Patent Document 1 discloses that the tension of the PC steel bar is evaluated based on the difference in propagation time of the reflected wave between the tension and non-tension of the PC steel bar. It is not disclosed how to determine the tension of the PC steel bar from the difference in propagation time, and the tension of the PC steel bar after releasing the tension by the jack has not been managed correctly.

本発明は、上記事情に鑑みてなされたものであり、ジャッキによる緊張を開放した後のPC鋼棒の張力を正確に管理することを課題とするものである。   This invention is made | formed in view of the said situation, and makes it a subject to manage correctly the tension | tensile_strength of PC steel bar after releasing the tension | tensile_strength by a jack.

上記課題を解決するために、本発明に係るPC鋼棒の張力の管理方法は、構造体に挿通されたPC鋼棒を流体圧式のジャッキで緊張させた状態でPC鋼棒のナットを締付け、その状態で前記ジャッキによるPC鋼棒の緊張を開放することにより、PC鋼棒を構造体に定着させる施工において、PC鋼棒の張力を管理する方法であって、前記ナットの締付前の前記ジャッキの流体圧と、前記ナットの締付完了時の前記ジャッキの流体圧の低下量と、前記ジャッキによる緊張を開放した後のPC鋼棒の張力との関係を予め求めておき、前記ジャッキによる緊張を開放した後のPC鋼棒の張力が所定値となるように、前記関係に基づいて、前記ナットの締付前の前記ジャッキの流体圧と、前記ナットの締付時の前記ジャッキの流体圧の低下量とを決定し、決定した量だけ前記ジャッキの流体圧が低下するように前記ナットの締付を行うことを特徴とする。   In order to solve the above-described problem, the PC steel rod tension management method according to the present invention includes tightening a nut of a PC steel rod in a state where the PC steel rod inserted through the structure is tensioned by a hydraulic jack, In the construction for fixing the PC steel bar to the structure by releasing the tension of the PC steel bar by the jack in that state, the method is to manage the tension of the PC steel bar, and before the nut is tightened, The relationship between the hydraulic pressure of the jack, the amount of decrease in the hydraulic pressure of the jack when the tightening of the nut is completed, and the tension of the PC steel rod after releasing the tension by the jack is determined in advance. Based on the above relationship, the hydraulic pressure of the jack before tightening the nut and the fluid of the jack at the time of tightening the nut so that the tension of the PC steel rod after releasing the tension becomes a predetermined value. Determine the amount of pressure drop And the determined amount by fluid pressure in the jack and performing tightening of the nut to decrease.

前記PC鋼棒の張力の管理方法において、前記ジャッキにより所定の流体圧で前記ナットの締付前のPC鋼棒を緊張させて当該PC鋼棒の張力を測定する工程と、前記ナットの締付完了時の前記ジャッキの流体圧を測定する工程と、前記ジャッキによるPC鋼棒の緊張を開放した後のPC鋼棒の張力を測定する工程と、を実施することにより前記関係を求めてもよい。   In the method for managing the tension of the PC steel bar, the step of measuring the tension of the PC steel bar by tensioning the PC steel bar before tightening the nut with a predetermined fluid pressure by the jack; and tightening the nut The relationship may be obtained by performing a step of measuring the fluid pressure of the jack at the time of completion and a step of measuring the tension of the PC steel rod after releasing the tension of the PC steel rod by the jack. .

本発明によれば、ジャッキによる緊張を開放した後のPC鋼棒の張力を正確に管理することができる。   ADVANTAGE OF THE INVENTION According to this invention, the tension | tensile_strength of PC steel bar after releasing the tension | tensile_strength by a jack can be managed correctly.

コンクリート構造体にプレストレスを導入している状態を示す断面図である。It is sectional drawing which shows the state which has introduce | transduced the prestress to a concrete structure. 定着開始から定着完了までのPC鋼棒の張力の増減を示すグラフである。It is a graph which shows increase / decrease in the tension | tensile_strength of PC steel bar from fixing start to fixing completion. ナットとPC鋼棒との螺合状態を拡大して示す図である。It is a figure which expands and shows the screwing state of a nut and a PC steel rod. PC鋼棒の張力の管理方法の概要を説明するためのグラフである。It is a graph for demonstrating the outline | summary of the management method of the tension | tensile_strength of PC steel bar. PC鋼棒の張力と油圧ジャッキの油圧との相関関係を求めるための実験をしている状態を示す断面図である。It is sectional drawing which shows the state which is doing the experiment for calculating | requiring the correlation with the tension | tensile_strength of PC steel bar, and the hydraulic pressure of a hydraulic jack. PC鋼棒の張力と油圧ジャッキの油圧との相関関係を求めるための実験の手順を示すフローチャートである。It is a flowchart which shows the procedure of the experiment for calculating | requiring the correlation with the tension | tensile_strength of PC steel bar, and the hydraulic pressure of a hydraulic jack. コンクリート構造体にプレストレスを導入する作業の手順を示すフローチャートである。It is a flowchart which shows the procedure of the operation | work which introduce | transduces prestress into a concrete structure.

以下、本発明の一実施形態を、図面を参照しながら説明する。図1は、油圧ジャッキ20によりPC鋼棒10を緊張させてコンクリート構造体1にプレストレスを導入している状態を示す断面図である。この図に示すように、PC鋼棒10は、梁や柱や壁や基礎等のコンクリート構造体1に空けられた貫通孔2に挿通され、両端に設けられたナット12及び支圧板13からなる定着具でコンクリート構造体1に定着される。このPC鋼棒10は、1〜3mの比較的短いものであり、緊張力による伸び量は数mm程度である。   Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing a state in which prestress is introduced into the concrete structure 1 by tensioning the PC steel rod 10 by the hydraulic jack 20. As shown in this figure, a PC steel bar 10 is inserted into a through hole 2 formed in a concrete structure 1 such as a beam, a column, a wall, or a foundation, and includes a nut 12 and a bearing plate 13 provided at both ends. It is fixed to the concrete structure 1 with a fixing tool. This PC steel bar 10 is a comparatively short thing of 1-3 m, and the elongation amount by tension | tensile_strength is about several mm.

油圧ジャッキ20は、内部にピストンが配されたシリンダ22と、ジャッキ反力を取るためのラムチェア24と、シリンダ22及びピストンに挿通されたロッド26と、ロッド26の一端側をピストンに固定するナット28とを備えている。ロッド26の他端側にはPC鋼棒10のネジ部と螺合する袋ナット26Aが形成されている。   The hydraulic jack 20 includes a cylinder 22 having a piston disposed therein, a ram chair 24 for taking jack reaction force, a rod 26 inserted through the cylinder 22 and the piston, and a nut for fixing one end of the rod 26 to the piston. 28. A cap nut 26 </ b> A is formed on the other end side of the rod 26 to be screwed with the threaded portion of the PC steel rod 10.

この油圧ジャッキ20では、油圧ポンプ30により圧油が供給されるとピストン及びロッド26がラムチェア24の反対側へ移動する。これにより、PC鋼棒10が緊張される。また、油圧ジャッキ20の油圧はマノメータ32により測定される。   In the hydraulic jack 20, when pressure oil is supplied from the hydraulic pump 30, the piston and the rod 26 move to the opposite side of the ram chair 24. Thereby, the PC steel bar 10 is tensioned. The hydraulic pressure of the hydraulic jack 20 is measured by a manometer 32.

コンクリート構造体1にプレストレスを導入する際には、PC鋼棒10の両端のナット12を支圧板13に当接させた状態にして、油圧ジャッキ20でPC鋼棒10を緊張させる。そして、油圧ジャッキ20側のナット12をレンチで回して締付けた後に、油圧ジャッキ20への油圧の供給を停止して油圧ジャッキ20によるPC鋼棒10の緊張を開放する。以上により、PC鋼棒10の緊張力によってコンクリート構造体1にプレストレスが与えられた状態になる。   When prestress is introduced into the concrete structure 1, the nuts 12 at both ends of the PC steel bar 10 are brought into contact with the support plate 13, and the PC steel bar 10 is tensioned by the hydraulic jack 20. Then, after tightening the nut 12 on the hydraulic jack 20 side with a wrench, the supply of hydraulic pressure to the hydraulic jack 20 is stopped and the tension of the PC steel rod 10 by the hydraulic jack 20 is released. As described above, the concrete structure 1 is prestressed by the tension of the PC steel bar 10.

図2は、ナット12の締付によるPC鋼棒10の定着開始から油圧ジャッキ20の油圧を開放することによるPC鋼棒10の定着完了までのPC鋼棒10の張力の増減を示すグラフである。このグラフに示すように、ナット12の締付作業を開始すると、PC鋼棒10に締付力が生じることによりPC鋼棒10の張力が増加する。そして、ナット12の締付を完了して、油圧ジャッキ20によるPC鋼棒10の緊張を開放すると、PC鋼棒10の張力は減少する。   FIG. 2 is a graph showing the increase or decrease in the tension of the PC steel rod 10 from the start of fixing of the PC steel rod 10 by tightening of the nut 12 to the completion of fixing of the PC steel rod 10 by releasing the hydraulic pressure of the hydraulic jack 20. . As shown in this graph, when the tightening operation of the nut 12 is started, a tightening force is generated in the PC steel rod 10, and the tension of the PC steel rod 10 is increased. When the tightening of the nut 12 is completed and the tension of the PC steel bar 10 by the hydraulic jack 20 is released, the tension of the PC steel bar 10 decreases.

ここで、図3に示すように、ナット12の雌ネジとPC鋼棒10の雄ネジとの間には微小な隙間が存在するため、PC鋼棒10には、その隙間の分のセット量が存在する。従って、油圧ジャッキ20によるPC鋼棒10の緊張を開放した後、上記セット量の分だけ、PC鋼棒10の伸びが減少し、PC鋼棒10の張力が減少する。   Here, as shown in FIG. 3, since there is a minute gap between the female screw of the nut 12 and the male screw of the PC steel rod 10, the PC steel rod 10 has a set amount corresponding to the gap. Exists. Therefore, after releasing the tension of the PC steel rod 10 by the hydraulic jack 20, the elongation of the PC steel rod 10 is reduced by the amount of the set amount, and the tension of the PC steel rod 10 is reduced.

特に、本実施形態で張力を管理するPC鋼棒10は、1〜3mと比較的短いところ、元々の伸びが数mm程度と小さいため、セット量による緊張力の減少率が大きくなり、その影響が大きくなる場合がある。例えば、伸びが4mmでセット量による伸びの減少が0.5mmの場合、セット量による緊張力の減少率は12.5%となり、その影響は大きくなる。   In particular, the PC steel rod 10 for managing the tension in this embodiment is relatively short as 1 to 3 m, and since the original elongation is as small as several millimeters, the rate of decrease in tension due to the set amount increases, and the influence thereof. May become larger. For example, when the elongation is 4 mm and the decrease in elongation due to the set amount is 0.5 mm, the decreasing rate of the tension force due to the set amount is 12.5%, and the influence becomes large.

そこで、本実施形態に係るPC鋼棒10の張力の管理方法では、PC鋼棒10の張力を、油圧ジャッキ20によるPC鋼棒10の緊張を開放した後のセット量による減少分を考慮して管理する。   Therefore, in the method for managing the tension of the PC steel rod 10 according to the present embodiment, the tension of the PC steel rod 10 is taken into consideration by the amount of decrease due to the set amount after the tension of the PC steel rod 10 by the hydraulic jack 20 is released. to manage.

図4は、本実施形態に係るPC鋼棒10の張力の管理方法の概要を説明するためのグラフである。このグラフに示すように、ナット12の締付作業を開始すると、PC鋼棒10に締付力が生じることによりPC鋼棒10の張力が増加する一方、油圧ジャッキ20によるPC鋼棒10の張力の負担が減少することにより油圧ジャッキ20の油圧は低下する。   FIG. 4 is a graph for explaining an outline of a tension management method for the PC steel rod 10 according to the present embodiment. As shown in this graph, when the tightening operation of the nut 12 is started, the tension of the PC steel rod 10 increases due to the tightening force generated on the PC steel rod 10, while the tension of the PC steel rod 10 by the hydraulic jack 20 is increased. As a result, the hydraulic pressure of the hydraulic jack 20 decreases.

ここで、ナット12の締付開始時から締付完了時までのPC鋼棒10の張力に応じて、油圧ジャッキ20の油圧が低下し、油圧ジャッキ20による緊張を開放した後のPC鋼棒の張力が低下する。即ち、ナット12の締付開始時、締付完了時、及び油圧開放時のPC鋼棒10の張力と、ナット12の締付開始時の油圧ジャッキ20の油圧と、ナット12の締付開始時から締付完了時までの油圧ジャッキ20の油圧の低下量との間には相関関係がある。   Here, the hydraulic pressure of the hydraulic jack 20 decreases according to the tension of the PC steel rod 10 from the start of tightening of the nut 12 to the completion of tightening, and the PC steel rod after the tension by the hydraulic jack 20 is released is released. Tension decreases. That is, the tension of the PC steel rod 10 at the start of tightening of the nut 12, when the tightening is completed, and when the hydraulic pressure is released, the hydraulic pressure of the hydraulic jack 20 at the start of tightening of the nut 12, and the tightening of the nut 12 There is a correlation between the amount of decrease in the hydraulic pressure of the hydraulic jack 20 from when the tightening is completed to when the tightening is completed.

そこで、本実施形態に係るPC鋼棒10の張力の管理方法では上記相関関係を実験で求めておき、その相関関係に基づいて、油圧ジャッキ20の油圧を指標としてナット12の締付を行う。   Therefore, in the method for managing the tension of the PC steel rod 10 according to the present embodiment, the above correlation is obtained by experiment, and the nut 12 is tightened using the hydraulic pressure of the hydraulic jack 20 as an index based on the correlation.

図5は、上記相関関係を求めるための実験をしている状態を示す図であり、図6は、当該実験の手順を示すフローチャートである。当該実験では、図5に示すように、PC鋼棒10の一端側は油圧ジャッキ20のロッド26の袋ナット26Aに螺合させ、当該一端側のナット12は支圧板13に当接させる。一方、PC鋼棒10の他端側のナット12と支圧板13との間にはロードセル等の歪ゲージ(荷重計)34を設置する(ステップ1)。   FIG. 5 is a diagram illustrating a state in which an experiment for obtaining the correlation is performed, and FIG. 6 is a flowchart illustrating a procedure of the experiment. In the experiment, as shown in FIG. 5, one end of the PC steel rod 10 is screwed into a cap nut 26 </ b> A of the rod 26 of the hydraulic jack 20, and the nut 12 on the one end is brought into contact with the bearing plate 13. On the other hand, a strain gauge (load meter) 34 such as a load cell is installed between the nut 12 on the other end side of the PC steel bar 10 and the bearing plate 13 (step 1).

次に、油圧ジャッキ20によりPC鋼棒10を緊張させる(ステップ2)。この際、油圧ジャッキ20の油圧は、PC鋼棒10の張力の設計値(例えば、40t)程度に設定し、歪ゲージ34でPC鋼棒10の張力を確認する。次に、ナット12の締付を開始し、歪ゲージ34の計測値が所定値(例えば、44t)になるとナット12の締付を完了する(ステップ3)。この際、油圧ジャッキ20の油圧(例えば、締付開始時に対して80%の値)をマノメータ32で確認する。   Next, the PC steel bar 10 is tensioned by the hydraulic jack 20 (step 2). At this time, the hydraulic pressure of the hydraulic jack 20 is set to about the design value (for example, 40 t) of the tension of the PC steel rod 10, and the tension of the PC steel rod 10 is confirmed by the strain gauge 34. Next, tightening of the nut 12 is started, and when the measured value of the strain gauge 34 reaches a predetermined value (for example, 44 t), tightening of the nut 12 is completed (step 3). At this time, the hydraulic pressure of the hydraulic jack 20 (for example, a value of 80% with respect to the start of tightening) is confirmed by the manometer 32.

次に、油圧ジャッキ20によるPC鋼棒10の緊張を開放する(ステップ4)。次に、歪ゲージ34の値を確認して、設計値以上であるか否かを判断する(ステップ5)。そして、歪ゲージ34の値が設計値以上である場合には、ナット12の締付開始時の油圧ジャッキ20の油圧、締付完了時の油圧ジャッキ20の油圧を、施工時の設定値とする(ステップ6)。一方、歪ゲージ34の計測値が設計値未満である場合には、ナット12の締付開始時の油圧ジャッキ20の油圧をより高い値(例えば、42t)に上げてから(ステップ7)、ステップ2〜4を繰返す。そして、油圧ジャッキ20によるPC鋼棒10の緊張を開放した後の歪ゲージ34の計測値が設計緊張力以上であれば、ナット12の締付開始時の油圧ジャッキ20の油圧、締付完了時の油圧ジャッキ20の油圧を、施工時の設定値とする(ステップ6)。   Next, the tension of the PC steel bar 10 by the hydraulic jack 20 is released (step 4). Next, the value of the strain gauge 34 is confirmed, and it is determined whether or not the value is greater than the design value (step 5). When the value of the strain gauge 34 is equal to or greater than the design value, the hydraulic pressure of the hydraulic jack 20 at the start of tightening of the nut 12 and the hydraulic pressure of the hydraulic jack 20 at the completion of tightening are set values at the time of construction. (Step 6). On the other hand, when the measured value of the strain gauge 34 is less than the design value, the hydraulic pressure of the hydraulic jack 20 at the start of tightening of the nut 12 is increased to a higher value (for example, 42 t) (step 7), and then the step Repeat steps 2-4. And if the measured value of the strain gauge 34 after releasing the tension | tensile_strength of the PC steel rod 10 by the hydraulic jack 20 is more than design tension | tensile_strength, the hydraulic pressure of the hydraulic jack 20 at the time of the clamping | tightening start of the nut 12, and completion | finish of clamping | tightening The hydraulic pressure of the hydraulic jack 20 is set as a set value at the time of construction (step 6).

図7は、コンクリート構造体1にプレストレスを導入する作業の手順を示すフローチャートである。このフローチャートに示すように、まず、油圧ジャッキ20によりPC鋼棒10を緊張させる(ステップ11)。この際の油圧ジャッキ20の油圧は、上記実験で求めたナット12の締付開始時の油圧(例えば、42t)に設定する。   FIG. 7 is a flowchart showing a procedure of work for introducing prestress into the concrete structure 1. As shown in this flowchart, first, the PC steel rod 10 is tensioned by the hydraulic jack 20 (step 11). The hydraulic pressure of the hydraulic jack 20 at this time is set to the hydraulic pressure (for example, 42 t) at the start of tightening of the nut 12 obtained in the above experiment.

次に、マノメータ32の値を確認しながら、ナット12を締付け、油圧ジャッキ20の油圧が上記実験で求めた値(例えば、締付開始時の80%の値)まで低下するとナット12の締付を完了する(ステップ12)。次に、油圧ジャッキ20によるPC鋼棒10の緊張を開放する(ステップ13)。   Next, the nut 12 is tightened while checking the value of the manometer 32, and the nut 12 is tightened when the hydraulic pressure of the hydraulic jack 20 drops to the value obtained in the above-described experiment (for example, 80% at the start of tightening). Is completed (step 12). Next, the tension of the PC steel bar 10 by the hydraulic jack 20 is released (step 13).

以上により、ナット12の締付開始から油圧ジャッキ20による緊張を解放した後までのPC鋼棒10の張力を、油圧ジャッキ20の油圧という数値で管理することによって、ナット12の締付力やセット量を一定にすることができ、油圧ジャッキ20による緊張を開放した後のPC鋼棒10の張力を所望の値(設計緊張力)に管理することができる。特に、本実施形態では、PC鋼棒10が1〜3mと比較的短く、油圧ジャッキ20による緊張を開放した後のPC鋼棒10の張力の減少率が高いため、効果的である。   As described above, the tension of the nut 12 is controlled by managing the tension of the PC steel rod 10 from the start of tightening of the nut 12 until the tension released by the hydraulic jack 20 is released by the numerical value of the hydraulic pressure of the hydraulic jack 20. The amount can be made constant, and the tension of the PC steel bar 10 after releasing the tension by the hydraulic jack 20 can be managed to a desired value (design tension). In particular, the present embodiment is effective because the PC steel rod 10 is relatively short as 1 to 3 m and the rate of decrease in the tension of the PC steel rod 10 after releasing the tension by the hydraulic jack 20 is high.

なお、上述の実施形態は、本発明の理解を容易にするためのものであり、本発明を限定するものではない。本発明はその趣旨を逸脱することなく、変更、改良され得ると共に本発明にはその等価物が含まれることは勿論である。例えば、上述の実施形態では、梁や柱や壁や基礎等のコンクリート構造体1にプレストレスを導入する例を挙げて本発明を説明したが、PC鋼棒10を用いてコンクリート構造体同士を結合したり、コンクリート構造体に鉄骨や鉄板等を結合したりする場合にも本発明を適用することができる。   In addition, the above-mentioned embodiment is for making an understanding of this invention easy, and does not limit this invention. It goes without saying that the present invention can be changed and improved without departing from the gist thereof, and that the present invention includes equivalents thereof. For example, in the above-described embodiment, the present invention has been described with reference to an example in which prestress is introduced into the concrete structure 1 such as a beam, a column, a wall, or a foundation. The present invention can also be applied to the case where the steel frame, the steel plate, or the like is joined to the concrete structure.

また、上述の実施形態では、PC鋼棒10の張力と油圧ジャッキ20の油圧との相関関係を、実験により求めたが解析により求めてもよい。また、上述の実施形態では、1〜3mの比較的短いPC鋼棒10を例に挙げて本発明を説明したが、それよりも長いPC鋼棒10にも本発明を適用することができる。さらに、上述の実施形態では、油圧ジャッキを用いた例を挙げて本発明を説明したが、他の液体や気体等の他の作動流体の圧力でPC鋼棒を緊張させる他の流体圧式のジャッキを用いた場合にも本発明を適用することができる。   In the above-described embodiment, the correlation between the tension of the PC steel bar 10 and the hydraulic pressure of the hydraulic jack 20 is obtained by experiment, but may be obtained by analysis. In the above-described embodiment, the present invention has been described by taking the PC steel rod 10 having a relatively short length of 1 to 3 m as an example. However, the present invention can also be applied to a PC steel rod 10 longer than that. Furthermore, in the above-described embodiment, the present invention has been described with an example using a hydraulic jack. However, other hydraulic jacks that tension a PC steel bar with the pressure of another working fluid such as another liquid or gas. The present invention can also be applied to the case where is used.

1 コンクリート構造体(構造体)、2 貫通孔、10 PC鋼棒、12 ナット、13 支圧板、20 油圧ジャッキ(ジャッキ)、22 シリンダ、24 ラムチェア、26 ロッド、26A 袋ナット、28 ナット、30 油圧ポンプ、32 マノメータ(油圧計)、34 歪ゲージ(荷重計) DESCRIPTION OF SYMBOLS 1 Concrete structure (structure), 2 Through-hole, 10 PC steel bar, 12 nut, 13 Supporting plate, 20 Hydraulic jack (jack), 22 Cylinder, 24 Ram chair, 26 Rod, 26A Cap nut, 28 Nut, 30 Hydraulic pressure Pump, 32 Manometer (hydraulic gauge), 34 Strain gauge (load gauge)

Claims (2)

構造体に挿通されたPC鋼棒を流体圧式のジャッキで緊張させた状態でPC鋼棒のナットを締付け、その状態で前記ジャッキによるPC鋼棒の緊張を開放することにより、PC鋼棒を構造体に定着させる施工において、PC鋼棒の張力を管理する方法であって、
前記ナットの締付前の前記ジャッキの流体圧と、前記ナットの締付完了時の前記ジャッキの流体圧の低下量と、前記ジャッキによる緊張を開放した後のPC鋼棒の張力との関係を予め求めておき、
前記ジャッキによる緊張を開放した後のPC鋼棒の張力が所定値となるように、前記関係に基づいて、前記ナットの締付前の前記ジャッキの流体圧と、前記ナットの締付時の前記ジャッキの流体圧の低下量とを決定し、決定した量だけ前記ジャッキの流体圧が低下するように前記ナットの締付を行うことを特徴とするPC鋼棒の張力の管理方法。
The PC steel rod is structured by tightening the nut of the PC steel rod while the PC steel rod inserted through the structure is tensioned by the hydraulic pressure jack, and releasing the tension of the PC steel rod by the jack in that state. In the construction to fix to the body, a method of managing the tension of the PC steel bar,
The relationship between the fluid pressure of the jack before tightening the nut, the amount of decrease in the fluid pressure of the jack when the tightening of the nut is completed, and the tension of the PC steel rod after releasing the tension by the jack Find in advance,
Based on the relationship, the hydraulic pressure of the jack before the nut is tightened and the nut when the nut is tightened so that the tension of the PC steel rod after releasing the tension due to the jack becomes a predetermined value. A method for managing the tension of a PC steel rod, wherein the amount of decrease in the fluid pressure of the jack is determined, and the nut is tightened so that the fluid pressure of the jack is decreased by the determined amount.
前記ジャッキにより所定の流体圧で前記ナットの締付前のPC鋼棒を緊張させて当該PC鋼棒の張力を測定する工程と、
前記ナットの締付完了時の前記ジャッキの流体圧を測定する工程と、
前記ジャッキによるPC鋼棒の緊張を開放した後のPC鋼棒の張力を測定する工程と、
を実施することにより前記関係を求めることを特徴とする請求項1に記載のPC鋼棒の張力の管理方法。
Tensioning the PC steel rod before tightening the nut with a predetermined fluid pressure by the jack and measuring the tension of the PC steel rod;
Measuring the fluid pressure of the jack at the completion of tightening the nut;
Measuring the tension of the PC steel bar after releasing the tension of the PC steel bar by the jack;
The method of managing the tension of the PC steel bar according to claim 1, wherein the relationship is obtained by performing the following.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017079987A1 (en) * 2015-11-11 2017-05-18 陈菲 Construction method for improving compressive capacity of component

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Publication number Priority date Publication date Assignee Title
JPS6416607A (en) * 1987-07-10 1989-01-20 Sato Kogyo Automatic control device of tension jack for prestressed construction
JPH06347357A (en) * 1993-06-03 1994-12-22 Nippon Concrete Ind Co Ltd Hydraulic tensioning apparatus
JPH10102776A (en) * 1996-09-27 1998-04-21 High Frequency Heattreat Co Ltd Method and device for measuring tension of pc steel bar for prestressed concrete
JP2002213083A (en) * 2001-01-17 2002-07-31 Ps Corp Method and apparatus for tensioning pc steel
JP2003314059A (en) * 2002-04-23 2003-11-06 Ps Mitsubishi Construction Co Ltd Tensioning apparatus for pc steel member
JP2013036244A (en) * 2011-08-09 2013-02-21 Okkusu Jack Kk Straining jack device

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Publication number Priority date Publication date Assignee Title
JPS6416607A (en) * 1987-07-10 1989-01-20 Sato Kogyo Automatic control device of tension jack for prestressed construction
JPH06347357A (en) * 1993-06-03 1994-12-22 Nippon Concrete Ind Co Ltd Hydraulic tensioning apparatus
JPH10102776A (en) * 1996-09-27 1998-04-21 High Frequency Heattreat Co Ltd Method and device for measuring tension of pc steel bar for prestressed concrete
JP2002213083A (en) * 2001-01-17 2002-07-31 Ps Corp Method and apparatus for tensioning pc steel
JP2003314059A (en) * 2002-04-23 2003-11-06 Ps Mitsubishi Construction Co Ltd Tensioning apparatus for pc steel member
JP2013036244A (en) * 2011-08-09 2013-02-21 Okkusu Jack Kk Straining jack device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017079987A1 (en) * 2015-11-11 2017-05-18 陈菲 Construction method for improving compressive capacity of component

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