JP5991481B2 - Jack operation system and jack control system and method in underpinning - Google Patents

Description

  The present invention relates to a jack operation system, a jack control system, and a method applied when an underground structure is constructed by an underpinning method.

  When constructing underground structures in the underground space, change the load of the existing structures so that the existing structures such as buildings and viaducts built on the ground will not be affected. Underpinning methods are used, but underground structures such as road tunnels and railway tunnels are often built in urban areas. In such cases, these underground structures are also installed. Since it is necessary to replace the load as a structure, the underpinning method requires higher reliability and safety.

  In order to construct an underground structure using the underpinning method, a replacement structure composed of temporary support girders and temporary support piles is built in the ground in advance, and the load of the existing structure is received by the replacement structure. While exchanging, the lower part of the existing structure is excavated to construct a new underground structure at the excavation site.

  Here, the replacement structure may be sunk or raised. In this case, vertical displacement occurs in the existing structure supported by the replacement structure, or the existing structure is replaced with the replacement structure. The flow of power fluctuates.

  Therefore, when constructing underground structures using the underpinning method, while monitoring the vertical displacement of existing structures, it is monitored whether the measured value does not exceed the allowable value, and the vertical displacement may exceed the allowable value. When there is an existing structure, it is necessary to adjust the vertical displacement of the existing structure by expanding and contracting the jack arranged between the existing structure and the replacement structure. However, if the service cannot be interrupted, the vertical displacement of the existing structure must be suppressed to, for example, about several millimeters or less from the viewpoint of safety during vehicle travel.

  Also, by monitoring the load transmitted from the existing structure to the replacement structure by measuring the load borne by the jack as the support load, if there is a concern that the support load of the jack will exceed the allowable value, It is necessary to be careful not to generate excessive stress in the existing structure or replacement structure by shrinking.

Japanese Patent Laid-Open No. 2004-150151 JP 2004-107971 A

  However, subsidence and uplift of the replacement structure are caused by various factors intricately affecting each other. Therefore, when the vertical displacement or support load at a certain support point exceeds the allowable value, the vertical displacement or support load is increased. Even if the jack of the support point is operated in the direction of decreasing, the vertical displacement and the support load may not be adjusted as intended, for example, the jack can be expanded and contracted at the support point where the vertical displacement exceeds the allowable value. Even if the vertical displacement cannot be kept below the allowable value, or if the jack is retracted at the support point where the support load exceeds the allowable value, the support load will not drop, but at the surrounding support points. There has been a problem that the vertical displacement becomes excessive.

  The present invention has been made in consideration of the above-mentioned circumstances, and when an underground structure is constructed by the underpinning method, it is possible to adjust the vertical displacement of the existing structure and the support load of the jack as intended. An object of the present invention is to provide a jack operating system and a jack control system and method in underpinning.

In order to achieve the above object, a jack operation system in underpinning according to the present invention includes an existing structure and a replacement structure that is positioned below and replaces the load of the existing structure. A jack placed between the
Position measuring means for measuring the vertical position of the existing structure at a support point of the jack;
Load measuring means for measuring the load borne by the jack as a support load;
From the measured values of the vertical position at two different times obtained by the position measuring means, the variation tendency of the vertical position is determined, and the measured values of the support load at the two times obtained by the load measuring means. From the above, it is determined that the variation tendency of the vertical load is downward, and when the variation tendency of the vertical position is upward and the variation tendency of the support load is increased, When the load fluctuation trend is decreasing, when the vertical position fluctuation trend is upward and the support load fluctuation trend is decreasing, and when the vertical position fluctuation trend is downward and the support load fluctuation trend is increasing. Arithmetic processing means for classifying in some cases;
Output means for outputting the result of classification performed by the arithmetic processing means.

  Moreover, the jack operation system in the underpinning according to the present invention is configured such that the output means is output so that the classification result is output for each jack together with the arrangement state of the jack.

  Further, as described in claim 3, the jack control system for underpinning according to the present invention is disposed between an existing structure and a replacement structure that is positioned below and replaces the load of the existing structure. A jack, a position measuring means for measuring a vertical position of the existing structure at a support point of the jack, a load measuring means for measuring a load borne by the jack as a support load, and driving control of the jack. Control means, and the control means determines the fluctuation tendency of the vertical position from the measured values of the vertical position at two different times obtained by the position measuring means and is obtained by the load measuring means. The variation tendency of the support load is determined from the measurement value of the support load at the two times, the variation tendency of the vertical position is upward, and the variation tendency of the support load is The jack is contracted so that the jack contracts when the load is applied, and the jack is driven and controlled so that the jack elongates when the tendency of fluctuation of the vertical position is downward and the tendency of fluctuation of the support load is reduced When the fluctuation tendency of the vertical position is upward and the fluctuation tendency of the support load is decreasing, or when the fluctuation tendency of the vertical position is downward and the fluctuation tendency of the support load is increasing, the jack is excluded from the operation target. It is what is supposed to do.

According to the jack control method of the present invention for underpinning, as described in claim 4, the existing structure is provided via a jack disposed between the existing structure and a replacement structure located below the existing structure. In the jack operation method in underpinning that replaces the load of the above with the replacement structure,
Measure the vertical position of the existing structure at the support point of the jack and measure the load borne by the jack as a support load,
Among the measured vertical positions, the variation tendency of the vertical position is determined from the measurement values at two different times, and the variation tendency of the support load is determined from the measurement values at the two times among the support loads. Judgment,
When the fluctuation tendency of the vertical position is upward and the fluctuation tendency of the support load is increasing, the jack is contracted, and when the fluctuation tendency of the vertical position is downward and the fluctuation tendency of the support load is decreasing, While extending the jack, when the fluctuation tendency of the vertical position is upward and the fluctuation tendency of the support load is decreasing or when the fluctuation tendency of the vertical position is downward and the fluctuation tendency of the support load is increasing, The jack is not operated.

  When the load of an existing structure is replaced with a replacement structure using the underpinning method, vertical displacement occurs in the existing structure, in other words, the cause of fluctuation in the vertical position of the existing structure, or the support load of the jack varies. The reason for this is mainly due to the subsidence or uplift of the replacement structure. If the existing structure has a certain planar extension and multiple jacks are arranged over the extension range, the replacement is performed at a certain support point. The subsidence or uplift of the structure affects not only the support point but also other support points in the form of fluctuations in the vertical position and support load at the support points.

  Therefore, just because the vertical position of an existing structure fluctuates at a certain support point does not necessarily mean that the replacement structure has sunk or raised at that support point. Even if the jack is extended with respect to the fluctuation of the vertical position, the fluctuation of the vertical position may not be restored.

  The same applies to the support load. Just because the support load of the jack fluctuates at a certain support point does not necessarily mean that the replacement structure has sunk or raised at that support point. Even if the jack is contracted or the jack is extended in response to a decrease in the support load, the change in the support load may not be restored.

  Based on this situation, the present applicant has analyzed and measured the measurement data obtained in actual construction in detail. Only the vertical position fluctuation of the existing structure at a certain support point is determined for jacking operation. Instead of adding the support load fluctuation of the jack at the support point to the judgment object, the vertical position fluctuation of the existing structure observed at the support point causes the subsidence bulging of the replacement structure at the support point. Distinguish between the cause and the cause of subsidence of the replacement structure at another support point, or only the change in the support load of the jack at a support point Instead, the vertical position fluctuation of the existing structure at the support point is also added to the judgment object, so that the change in the jack support load observed at the support point is received at the support point. Judgment of jack operation can be made after distinguishing whether it is caused by the subsidence bulge of the structure or the subsidence bulge of the replacement structure at another support point We have found new knowledge.

[First invention]
That is, in the jack operating system in the underpinning according to the first invention, the jack is arranged and operated between the existing structure and the replacement structure that receives the load. In operating the jack, first, the processing means determines whether the fluctuation tendency is upward or downward from the measured values of the vertical position at two different times obtained by the position measuring means, and the load Based on the measured values of the support load at the above two times obtained by the measuring means, the arithmetic processing means determines whether the fluctuation tendency is increasing or decreasing.

Next, each determined tendency of the vertical position and the supporting load is classified as follows. That is,
(a) When the fluctuation tendency of the vertical position is upward and the fluctuation tendency of the supporting load is increasing
(b) When the fluctuation tendency of the vertical position is downward and the fluctuation tendency of the supporting load is decreasing
(c) When the fluctuation tendency of the vertical position is upward and the fluctuation tendency of the supporting load is decreasing
(d) When the fluctuation tendency of the vertical position is downward and the fluctuation tendency of the support load is increasing

  It can be generally determined that the vertical position fluctuates upward at a certain support point due to the uplift of the replacement structure, but it is not known whether the uplift point is the support point.

  However, if the change tendency of the support load at the support point is examined and judged together with the change tendency, the increase in the support load means that the replacement structure is raised immediately below, and the support load is increased. Since the decrease in load means that the replacement structure has risen in the vicinity, the load that has been borne until now flows in the vicinity, so in the case of (a), In the case of (c), the replacement structure existing immediately below the support point is raised, and in the case of (c), it is assumed that the replacement structure existing below the other support point, particularly the nearby support point, is raised. Judgment can be made.

  Moreover, it can be generally determined that the vertical position fluctuates downward at a certain support point due to the sinking of the replacement structure, but it is not known whether the sinking point is the support point.

  However, if the change tendency of the support load at the support point is examined and judged together with the change tendency, the decrease in the support load means that the replacement structure has subsided immediately below it. In the case of (b), the increase in load means that the load that was borne by the support point in the vicinity began to flow directly underneath because the displacement of the replacement structure occurred in the vicinity. In the case of (d), the replacement structure existing immediately below the supporting point sinks. Can be determined to have sunk.

  Therefore, if the classification results of (a) to (d) are output by the output means, the vertical position fluctuation of the existing structure and the support load fluctuation of the jack observed at a certain support point are directly below the support point. It can be easily discriminated whether it is caused by the behavior of the replacement structure or whether it is caused by the behavior of the replacement structure at other support points in the vicinity of the support point. Based on the above, the jack is driven and controlled so that the jack contracts in the case of (a) and the jack extends in the case of (b), and the jack is controlled in the case of (c) or (d). It is possible to determine the operation contents that are not subject to operation. Thus, instead of trial and error, rational jack operation with only necessary and sufficient jacks as the object of operation, vertical position fluctuations in existing structures, in other words If vertical displacement occurs The variation of the support load of the jack can be prevented.

  The output means can be constituted by a display means such as a printer or a display or an audio output means.

  Here, the form in which the classification results of (a) to (d) are output is arbitrary, but the above classification result is output for each jack together with the arrangement status of the jack. If the output means is configured, it is possible to grasp at a glance which jack should be operated and how to operate the jack in underpinning more rationally.

[Second invention]
In the jack control system and method in the underpinning according to the second invention, the jack is arranged between the existing structure and the replacement structure for changing the load, and the jack is driven and controlled by the control means. However, in controlling the drive of the jack, first, from the measured values of the vertical position at two different times obtained by the position measuring means, it is determined whether the fluctuation tendency is upward or downward, From the measured values of the supporting load at the above two times obtained by the load measuring means, it is determined whether the variation tendency is increasing or decreasing.

Next, the contents of the jack operation are determined based on the determined vertical position and the variation tendency of the support load as follows. That is,
(a ′) When the fluctuation tendency of the vertical position is upward and the fluctuation tendency of the supporting load is increasing, the jack at the supporting point is contracted.
(b ′) When the fluctuation tendency of the vertical position is downward and the fluctuation tendency of the supporting load is decreasing, the jack at the supporting point is extended.
(c ′) When the vertical position fluctuation trend is upward and the support load fluctuation tendency is decreasing, the jack at the support point is excluded from the operation target and no special operation is performed.
(d ') When the vertical position fluctuation trend is downward and the support load fluctuation trend is increasing, the jack at the support point is excluded from the operation target and no special operation is performed as in (c).

  In this way, as described in the first invention, the vertical position fluctuation of the existing structure and the jack support load fluctuation observed at a certain support point are caused by the behavior of the replacement structure immediately below the support point. It is possible to determine the content of the jack operation after distinguishing whether it occurred due to the behavior of the replacement structure at the other support point in the vicinity of the support point, and thus trial and error. Rather than relying on this, rational jack operation with only necessary and sufficient jacks as the object of operation prevents vertical position fluctuations in existing structures, in other words, vertical displacement and jack support load fluctuations. be able to.

  As long as the position measuring means can grasp the vertical position of the existing structure at each support point, the configuration is arbitrary, and the vertical position of each support point is measured individually and directly. First, measure the vertical position and tilt angle around two horizontal axes at the representative points of the existing structure, or measure the vertical position at two different points of the existing structure, and convert the measured values to coordinates Thus, an indirect measurement configuration that obtains the vertical position at each support point can also be adopted.

  For example, the position measuring means may be configured by installing a displacement meter on the bottom plate of the box constituting the existing structure.

  The load measuring means can be configured using a pressure gauge built in the jack.

  The subsidence or uplift of the replacement structure is the local subsidence due to the deformation of the replacement structure or the structural elements including the subsidence or the uplift due to the entire movement of the replacement structure or the structural elements constituting the replacement structure Or, if the replacement structure is composed of a temporary support pile and a temporary support girder spanned over it, for example, the settlement of the temporary support pile or the elevation of the temporary support girder Subsidence, uplift, and bending of temporary support girders are included.

It is a figure of the jack operation system in the underpinning which concerns on this embodiment, (a) is a layout, (b) is a block diagram. Explanatory drawing which showed the effect | action of the jack operation system in the underpinning which concerns on this embodiment. The figure which showed a mode that the classification | category result of the fluctuation tendency of a vertical position and the fluctuation tendency of a support load was displayed on the display 11. FIG. It is a figure of the jack control system in underpinning which concerns on this embodiment, (a) is a layout, (b) is a block diagram. The flowchart which showed the implementation procedure of the jack control method in the underpinning which concerns on this embodiment.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of a jack operation system, a jack control system and a method in underpinning according to the present invention will be described with reference to the accompanying drawings.

[First Embodiment]
FIG. 1 is a view showing a jack operation system in underpinning according to the present embodiment. As shown in the figure, the jack operating system 1 according to the present embodiment uses a box 2 of a railway tunnel as an existing structure to be replaced, and the load of the box is a temporary receiving pile constructed on the ground 3. 4 and an underpinning method for constructing a new underground structure 6 below the temporary receiving girder 5 while receiving it with a replacement structure consisting of the temporary receiving girder 5 bridged over the temporary receiving pile. A plurality of hydraulic jacks 7 arranged between the temporary support beam 5 so that the box can be supported with the lower surface of the box 2 as a supporting point, and a position for measuring the vertical position of the box 2 A displacement meter 8 as a measuring means, a pressure gauge 13 as a load measuring means for measuring a load borne by the hydraulic jack 7 as a supporting load, and an arithmetic processing unit 9 as an arithmetic processing means are provided.

  The arithmetic processing unit 9 can be composed of hardware such as a CPU, a mother board, and a memory constituting the personal computer 12 and software operating on the hardware. The personal computer 12 stores storage means for storing various data. And a display 11 as an output means for outputting the result of the arithmetic processing performed by the arithmetic processing unit 9.

  The displacement meters 8 are respectively installed on the bottom slab constituting the box 2 and directly above the support point by the hydraulic jack 7 so that the vertical position of the box 2 at the support point can be measured. .

  The pressure gauge 13 can be configured so as to be built in each hydraulic jack 7.

The arithmetic processing unit 9 determines the fluctuation tendency of the vertical position from the measured values of the vertical position at two different times t ₁ and t ₂ obtained by the displacement gauge 8, and also calculates the two obtained by the pressure gauge 13. The variation tendency of the support load is determined from the measurement values of the support load at times t ₁ and t ₂ , and the determination result is determined based on the vertical position when the variation tendency of the vertical position is upward and the variation tendency of the support load is increasing. If the fluctuation trend of the vertical position is downward and the fluctuation tendency of the supporting load is decreasing, if the fluctuation tendency of the vertical position is upward and the fluctuation tendency of the supporting load is decreasing, or if the fluctuation tendency of the vertical position is downward and the fluctuation of the supporting load is Classification is made when the trend is an increase.

In the jack control system 1 according to this embodiment, if managed is a vertical displacement, when the deviation of the vertical position of the time t ₂ from the reference become vertical position exceeds the allowable value, the managed in support load If there is, if the deviation of the support load at time t ₂ from the reference support load exceeds the allowable value, from the measured values of the vertical position at _two different times t ₁ and t ₂ obtained by the displacement meter 8. The arithmetic processing unit 9 determines whether the fluctuation tendency is upward or downward, and the fluctuation tendency is increased from the measured values of the support loads at _two times t ₁ and t ₂ obtained by the pressure gauge 13. It is determined by the arithmetic processing unit 9 whether or not it is reduced.

  The measurement data of the vertical position and the supporting load may be appropriately stored in the hard disk 10 that is a storage unit, and may be displayed on the display 11 as necessary.

Next, each determined tendency of the vertical position and the supporting load is classified as follows. That is,
(a) When the fluctuation tendency of the vertical position is upward and the fluctuation tendency of the supporting load is increasing
(b) When the fluctuation tendency of the vertical position is downward and the fluctuation tendency of the supporting load is decreasing
(c) When the fluctuation tendency of the vertical position is upward and the fluctuation tendency of the supporting load is decreasing
(d) When the fluctuation tendency of the vertical position is downward and the fluctuation tendency of the support load is increasing

FIG. 2 (a) shows a state in which the right side temporary receiving pile 4 rises out of the three temporary receiving piles 4 constituting the replacement structure. Placement of the hydraulic jack 7 in FIG. 1 (a) because the box 2 shifts from the horizontal position (time t ₁ ) to the right-up state (time t ₂ ) in response to the rise of the temporary support pile. The vertical position fluctuations at the support points R ₁ , R ₂ , R ₃ , R ₄ , and R ₅ corresponding to are all upward, and the tendency increases toward the right side.

On the other hand, the support load of the hydraulic jack 7 at each support point shifts from, for example, a uniform load state (time t ₁ ) to a non-uniform state that is small at the support point R ₃ or the support point R ₄ and large at the support point R ₅ .

This is because the load transfer flow that the load previously supported at the support points R _{2 to} R ₄ flows to R ₅ due to the rise of the right temporary support pile 4 has occurred.

Therefore, the support load fluctuation tends to decrease at the support points R ₂ , R ₃ , and R ₄ and increase at R ₅ .

From the above, each variation tendency of the vertical position and the support load is classified into the above (c) at the support points R ₂ to R _{4 and} is classified as (a) at the support point R ₅ .

  Next, the classified result is displayed on the display 11.

  FIG. 3A shows a state in which the above-described classification result is displayed on the display 11, and the plane arrangement state of the hydraulic jack 7 arranged on the lower surface of the box 2 is supported by each hydraulic jack. The plane position of the point is shown as a lattice pattern 21 having a lattice center, and the inside of each lattice is colored with a color corresponding to the above-described classification result so that the classification result at each support point can be understood. .

  The lattice pattern 21 is created so that the material axis orthogonal direction (width direction) of the box 2 corresponds to the horizontal direction of the screen, and the material axis direction of the box corresponds to the vertical direction of the screen. By scrolling up and down, the arrangement state of the hydraulic jack 7 and the classification results at the respective support points can be smoothly browsed along the material axis direction of the box 2.

Here, the support points R ₁ to R ₅ correspond to the support points of the hydraulic jack 7 at the cross-sectional positions shown in FIG.

Thus, when the above-described classification result is displayed on the display 11, the grid 22a is colored “gray” indicating that there is no substantial variation in both the vertical position and the support load, and the grids 22b to 22d are in the above-described classification. Corresponding to (c), that is, the vertical position fluctuation trend is upward and the fluctuation tendency of the support load is colored “blue”, and the lattice 22e falls under (a) in the above classification. That is, since the vertical position fluctuation tendency is upward and the fluctuation tendency of the supporting load is increased, it is colored “red”. Therefore, at the support points R ₂ , R ₃ and R ₄ , the vertical position fluctuation tendency is Therefore, it can be determined that the uplift of the replacement structure occurs not below the respective support points but below the other support points. In addition, at the support point R ₅ , it can be determined that the vertical position fluctuation trend is upward and the support load fluctuation tendency is increasing, and thus the uplift of the replacement structure is generated directly below the support point.

FIG. 2 (b) shows the state when the right temporary receiving pile 4 of the three temporary receiving piles 4 constituting the replacement structure sinks. In response to the settlement of the temporary support pile, the box 2 shifts from the horizontal posture state (time t ₁ ) to the lower right state (time t ₂ ), so that the support points R ₁ , R ₂ , R ₃ , R The vertical position fluctuations at ₄ and R ₅ are both downward, and the tendency becomes larger toward the right side.

On the other hand, the support load of the hydraulic jack 7 at each support point shifts from, for example, a uniform load state (time t ₁ ) to an unequal state that is large at the support point R ₃ or the support point R ₄ and small at the support point R ₅ .

This is because the load transfer flow that the load supported at the support point R ₅ so far flows to R _{2 to} R ₄ is caused by the sinking of the right temporary support pile 4.

Therefore, the support load fluctuation tends to increase at the support points R ₂ , R ₃ , R ₄ and decrease at R ₅ .

From the above, each variation tendency of the vertical position and the support load is classified into the above (d) at the support point R ₂ to the support point R _{4 and} is classified into (b) at the support point R ₅ .

 FIG. 3B shows the classification result displayed on the display 11 as in FIG.

Thus, when the above-described classification result is displayed on the display 11, the grid 23a is colored "gray" indicating that there is no substantial variation in both the vertical position and the support load, and the grids 23b to 23d are in the above-described classification. Corresponding to (d), that is, the vertical position fluctuation trend is downward and the fluctuation tendency of the supporting load is increased, and the grid 23e falls under (b) in the above classification. In other words, since the vertical position fluctuation tendency is downward and the fluctuation tendency of the supporting load is reduced, it is colored “yellow”. Therefore, at the supporting points R ₂ , R ₃ and R ₄ , the vertical position fluctuation is The tendency is downward and the fluctuation tendency of the support load is increasing. Therefore, it can be determined that the replacement structure is subsidized not below the respective support points but below the other support points. Further, at the support point R ₅ , it can be determined that the vertical position fluctuation trend is downward and the support load fluctuation tendency is decreasing, and therefore the substituting structure is subsidized immediately below the support point.

  As described above, according to the jack operation system 1 in the underpinning according to the present embodiment, the vertical position fluctuation tendency and the support load fluctuation tendency are classified into any one of the above-described (a) to (d). Whether the vertical position fluctuation of the box 2 or the support load fluctuation of the hydraulic jack 7 observed at a certain support point is caused by the behavior of the replacement structure immediately below the support point, or in the vicinity of the support point. It is possible to easily determine whether it has occurred due to the behavior of the replacement structure at another support point, and based on the determination, in the case of (a), the hydraulic jack 7 is contracted. In the case of (b), the operation of the hydraulic jack 7 is controlled so that the hydraulic jack 7 is extended, and in the case of (c) or (d), the operation content is excluded from the jack operation target. Possible, thus trial It is not caused by mistakes, but by a rational jack operation with only the necessary and sufficient hydraulic jack 7 as an object of operation, the vertical position in the box 2 changes, in other words, the occurrence of vertical displacement and the change in the load on the hydraulic jack 7 Can be prevented in advance.

[Second Embodiment]
Next, a second embodiment will be described. In addition, about the component substantially the same as 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  FIG. 4 is a diagram showing a jack control system in underpinning according to the present embodiment. As shown in the figure, a jack control system 41 according to the present embodiment uses a box 2 of a railway tunnel as an existing structure to be replaced, and the load of the box is a temporary receiving pile constructed on the ground 3. 4 and an underpinning method for constructing a new underground structure 6 below the temporary receiving girder 5 while receiving it with a replacement structure consisting of the temporary receiving girder 5 bridged over the temporary receiving pile. A plurality of hydraulic jacks 7 arranged between the temporary support beam 5 so that the box can be supported with the lower surface of the box 2 as a supporting point, and a position for measuring the vertical position of the box 2 A displacement meter 8 as a measuring means, a pressure gauge 13 as a load measuring means for measuring a load borne by the hydraulic jack 7 as a supporting load, and a control unit 42 as a control means are provided. The drive of the jack 7 can be controlled.

  The control unit 42 can be configured by hardware such as a CPU, a mother board, and a memory constituting the personal computer 12 and software operating on the hardware, and the personal computer 12 has storage means for storing various data. The hard disk 10 and the display 11 are provided.

Here, the control unit 42 determines the fluctuation tendency of the vertical position from the measured values of the vertical position at two different times t ₁ and t ₂ obtained by the displacement gauge 8 and obtained by the pressure gauge 13. The variation tendency of the support load is determined from the measurement values of the support load at _two times t ₁ and t ₂ , and when the variation tendency of the vertical position is upward and the variation tendency of the support load is increasing, When the vertical position fluctuation tendency is downward and the support load fluctuation tendency is decreasing so that the hydraulic jack 7 contracts, the jacks are driven and controlled so that the hydraulic jack 7 at the support point extends. In addition, when the fluctuation tendency of the vertical position is upward and the fluctuation tendency of the support load is decreasing, or when the fluctuation tendency of the vertical position is downward and the fluctuation tendency of the support load is increasing, the hydraulic jack 7 at the support point is operated. It is supposed to be excluded from the work.

FIG. 5 is a flowchart showing a procedure for controlling the hydraulic jack 7 using the jack control system 41 according to the present embodiment. As can be seen from the figure, in the jack control system 41 according to the present embodiment, if the management target is a vertical displacement, the deviation of the vertical position at the time t ₂ from the reference vertical position exceeds the allowable value. If the management target is a support load, when the deviation of the support load at the time t ₂ from the reference support load exceeds an allowable value, two different times t ₁ and t ₂ obtained by the displacement meter 8 are obtained. From the measured value of the vertical position at, it is determined whether the fluctuation tendency is upward or downward (step 101), and from the measured values of the supporting load at _two times t ₁ and t ₂ obtained by the pressure gauge 13, It is determined whether the fluctuation tendency is increasing or decreasing (step 102).

  The measurement data of the vertical position and the supporting load may be appropriately stored in the hard disk 10 that is a storage unit, and may be displayed on the display 11 as necessary.

  Next, according to the determination result described above, when the fluctuation tendency of the vertical position is upward and the fluctuation tendency of the support load is increasing (step 103, YES), the hydraulic jack 7 at the support point is contracted. The jack is driven and controlled by the control unit 42 (step 107). When the fluctuation tendency of the vertical position is upward but the fluctuation tendency of the support load is decreasing (step 105, YES), the hydraulic jack 7 at the support point is turned on. It is excluded from the operation target, and no special operation is performed (step 109).

This will be explained in the example of FIG. 2 (a), since the determination of the R ₅ in the vertical position is also increased support load upward is made, to contract the hydraulic jack 7 in accordance with the determination (step 107) At the support points R ₂ , R ₃ , and R ₄ , it is determined that the fluctuation tendency of the vertical position is upward and the fluctuation of the support load is decreasing. Therefore, the hydraulic jack 7 is not operated at the support point. No special operation is performed (step 109).

In this manner, the vertical positions of the support point R ₂ to the support point R ₄ return to the state at the time t ₁ by the contraction operation of the hydraulic jack 7 at the support point R _5. The load flow is also restored.

By the way, according to the concept of including all hydraulic jacks of the supporting points where the fluctuation has occurred in the operation target as in the conventional case, in the example of FIG. 2 (a), there are four supporting points of the supporting points R ₂ to R _5. Since the vertical positions are raised, all the hydraulic jacks 7 arranged on them are contracted. In this case, the support points R ₂ , R ₃ , R ₄ are the temporary support piles 4 at the support point R ₅ . Since the uplift of the replacement structure does not occur just under the influence of the uplift of the replacement structure, the contraction of the jack at the support points R ₂ , R ₃ , R ₄ is unnecessary. It becomes an inefficient jack operation.

In addition, it is sufficient that only the hydraulic jack 7 disposed at the support point R ₅ is contracted, that is, the hydraulic jack at the support point R ₅ immediately above it is offset in order to offset the influence of the rising of the right temporary support pile 4. In a situation where it is sufficient to shorten only the stroke 7, if the contraction operation is also performed on the hydraulic jacks 7 of the supporting points R ₂ , R ₃ , R ₄ , that is, if the stroke amount is shortened, the box 2 Is returned to the original horizontal posture, the load that should have flowed to the support points R ₂ , R ₃ , R ₄ would flow to the support point R ₅ , causing an unexpected increase in support load at the support point. There are also concerns.

  On the other hand, when the fluctuation tendency of the vertical position is downward and the fluctuation tendency of the support load is decreasing (step 104, YES), the jack 42 is driven and controlled by the control unit 42 so that the hydraulic jack 7 at the support point extends. However, when the fluctuation tendency of the vertical position is downward but the fluctuation tendency of the support load is increasing (step 106, YES), the hydraulic jack 7 at the support point is excluded from the operation target, and the special operation is performed. Is not performed (step 110).

To explain this in the example of FIG. 2 (b), since the determination of the vertical position by R ₅ is also reduced support load in downward is made, by extending the hydraulic jack 7 in accordance with the determination (step 108) At the support points R ₂ , R ₃ , and R ₄ , it is determined that the fluctuation tendency of the vertical position is downward and the fluctuation tendency of the support load is increasing. Therefore, the hydraulic jack 7 is not operated at the support point. No special operation is performed (step 110).

In this way, the vertical position of the support point R ₂ to the support point R ₄ returns to the state at the time t _{1 as} a result of the extension operation of the hydraulic jack 7 at the support point R _5. The load flow is also restored.

By the way, according to the conventional concept of including hydraulic jacks of all the support points where fluctuation has occurred in the operation target as in the prior art, in the example of FIG. 2 (b), there are four support points from support point R ₂ to support point R _5. Since the vertical positions are lowered, all the hydraulic jacks 7 arranged on them are extended. In this case, the support points R ₂ , R ₃ , R ₄ are the temporary support piles 4 at the support point R ₅ . Jacking at the support points R ₂ , R ₃ , R ₄ is not necessary because the substituting structure is not subsidized immediately below them. It becomes an inefficient jack operation.

In addition, it is sufficient to extend only the hydraulic jack 7 arranged at the support point R ₅ , that is, in order to offset the influence of the settlement of the right temporary support pile 4, the hydraulic jack at the support point R ₅ immediately above it. In a situation where it is sufficient to lengthen only the stroke 7, if the extension operation is also performed on the hydraulic jacks 7 of the support points R ₂ , R ₃ , R ₄ , that is, if the stroke amount is lengthened, the box 2 Is returned to the original horizontal posture, the load that should flow to the support point R ₅ would flow to the support points R ₂ , R ₃ , and R ₄ , leading to an unexpected increase in support load at the support point. There are also concerns.

Further, when the management target is a support load, according to the concept of contracting the hydraulic jack at the support point where the load fluctuation exceeds the allowable value as in the conventional case, for example, _{three of} R ₂ , R ₃ , and R ₄ are used. Since the hydraulic jack 7 is contracted at the support point, in this case, since subsidence occurs immediately below the support point R ₅ , the support is performed even if the contraction operation is performed at the support points R ₂ , R ₃ , R _4. There is a concern that not only the load cannot be reduced but also the vertical displacement at the support point R ₅ is further increased.

  As described above, according to the jack control system 41 and the method in the underpinning according to the present embodiment, the vertical position fluctuation of the box 2 and the support load fluctuation of the hydraulic jack 7 observed at a certain support point are supported. The contents of the jack operation after distinguishing whether it was caused by the behavior of the replacement structure immediately below the point or caused by the behavior of the replacement structure at other supporting points in the vicinity of the supporting point Therefore, only the necessary and sufficient hydraulic jack 7 can be set as the operation target, and thus the vertical position variation in the box 2 can be changed by a reasonable jack operation rather than by trial and error. By doing so, it is possible to prevent vertical displacement and support load fluctuations.

  In addition, according to the jack control system and method in underpinning according to the present embodiment, by excluding the hydraulic jack 7 that does not need to be extended or retracted, the vertical position fluctuation or the support load fluctuation due to unnecessary stroke adjustment is avoided. It is also possible to prevent this from occurring.

1 Jack operation system 2 Box (existing structure)
4 Temporary receiving pile (replacement structure)
5 Provisional girder (replacement structure)
7 Hydraulic jack (jack)
8 Displacement meter (position measuring means)
9 Arithmetic processing part (arithmetic processing means)
11 Display (output means)
13 Pressure gauge (load measuring means)
41 Jack control system 42 Control unit (control means)

Claims (4)

A jack disposed between an existing structure and a replacement structure that is positioned below and replaces the load of the existing structure;
Position measuring means for measuring the vertical position of the existing structure at a support point of the jack;
Load measuring means for measuring the load borne by the jack as a support load;
From the measured values of the vertical position at two different times obtained by the position measuring means, the variation tendency of the vertical position is determined, and the measured values of the support load at the two times obtained by the load measuring means. From the above, it is determined that the variation tendency of the vertical load is downward, and when the variation tendency of the vertical position is upward and the variation tendency of the support load is increased, When the load fluctuation trend is decreasing, when the vertical position fluctuation trend is upward and the support load fluctuation trend is decreasing, and when the vertical position fluctuation trend is downward and the support load fluctuation trend is increasing. Arithmetic processing means for classifying in some cases;
A jack operation system in underpinning, comprising: output means for outputting a result of classification performed by the arithmetic processing means. The jack operation system in underpinning according to claim 1, wherein the output means is configured so that the classification result is output for each jack and together with an arrangement state of the jack. Position measurement for measuring the vertical position of the existing structure at a support point of the jack, and a jack disposed between the existing structure and a replacement structure positioned below and replacing the load of the existing structure Means, a load measuring means for measuring the load borne by the jack as a support load, and a control means for controlling the drive of the jack, the control means being different in two obtained by the position measuring means. Determining the fluctuation tendency of the vertical position from the measurement value of the vertical position at one time and determining the fluctuation tendency of the support load from the measurement value of the support load at the two times obtained by the load measuring means; When the fluctuation tendency of the vertical position is upward and the fluctuation tendency of the support load is increasing, the fluctuation tendency of the vertical position is downward and the support is so that the jack contracts. When the heavy fluctuation tendency is decreasing, the jacks are respectively driven and controlled so that the jacks extend, and when the vertical position fluctuation tendency is upward and the support load fluctuation tendency is decreasing, or the vertical position The jack control system in underpinning is characterized in that the jack is excluded from the operation target when the fluctuation tendency is downward and the fluctuation tendency of the support load is increasing. In the jack operation control method in the underpinning in which the load of the existing structure is replaced by the replacement structure via the jack disposed between the existing structure and the replacement structure positioned below the existing structure,
Measure the vertical position of the existing structure at the support point of the jack and measure the load borne by the jack as a support load,
Among the measured vertical positions, the variation tendency of the vertical position is determined from the measurement values at two different times, and the variation tendency of the support load is determined from the measurement values at the two times among the support loads. Judgment,
When the fluctuation tendency of the vertical position is upward and the fluctuation tendency of the support load is increasing, the jack is contracted, and when the fluctuation tendency of the vertical position is downward and the fluctuation tendency of the support load is decreasing, While extending the jack, when the fluctuation tendency of the vertical position is upward and the fluctuation tendency of the support load is decreasing or when the fluctuation tendency of the vertical position is downward and the fluctuation tendency of the support load is increasing, A jack control method in underpinning, characterized in that the jack is not subject to operation.

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