JP2024013643A - Measurement method of upper surface height of concrete - Google Patents

Abstract

To provide a measurement system which can measure an upper surface height of concrete and also easily measure a lower end position of a tremie pipe.SOLUTION: A measurement system 1 for automatically measuring an upper surface height of concrete C installed in a drilling hole, comprises: a measurement device 4 which measures a delivery amount of a wire 6; a turning part 5 which turns the extension direction of the wire drawn from the measurement device; a first weight 71 which is attached to the tip of the wire ahead of the turning part; a second weight 72 which is attached to the midway of the wire above the first weight; and a measurement instrument which has a penetration part vertically penetrating an arm part horizontally protruding from a tremie pipe.SELECTED DRAWING: Figure 1

Description

The present invention relates to a measuring instrument, a measuring system, and a method for measuring the height of the crown of concrete used when measuring the height of the crown of concrete placed in an excavation hole.

As disclosed in Patent Document 1, when pouring concrete into an excavated hole filled with stabilizing liquid in order to construct cast-in-place concrete piles, etc., the height of the top of the poured concrete is It is necessary to successively measure and understand.

The device for measuring the top of placed concrete in Patent Document 1 includes a wire having a weight and a detector attached to the tip, a wire winding device, and an encoder that measures the length of the wire wound. ing. Then, when the weight placed on the top of the concrete is pushed up by the rise of the top due to concrete pouring, the detector is pushed by the weight and the winding device is activated, causing the wire to be wound up. The structure is such that the length can be measured.

On the other hand, as disclosed in Patent Document 2, when concrete is poured into an excavation hole using a tremie pipe, it is necessary to prevent muddy water (stabilizing liquid) and groundwater from getting caught up in the concrete. First, it is necessary to ensure that the lower part of the tremie pipe is buried in the poured concrete.

Therefore, in the management device described in Patent Document 2, in addition to a concrete top depth measuring device using a weight and a wire, a plurality of RFIDs are separately attached to the tremie tube in order to grasp the lower end position of the tremie tube. It is equipped with a tag and a receiving device installed on the ground.

Patent No. 2869604 Japanese Patent Application Publication No. 2013-19241

However, the crown measuring device of Patent Document 1 can only measure the height of the concrete crown. On the other hand, in the management device of Patent Document 2, in order to measure the lower end position of the tremie tube, a measuring device for the tremie tube must be prepared in addition to the concrete top depth measuring device.

Therefore, the present invention provides a measuring instrument, a measuring system, and a method for measuring the crown height of concrete, which can not only measure the height of the crown of concrete but also easily measure the position of the lower end of the tremie pipe. It is intended to.

In order to achieve the above object, the measuring instrument of the present invention is a measuring instrument used when measuring the height of the top of concrete placed in an excavation hole, and the measuring instrument is a measuring instrument used when measuring the height of the top of concrete placed in an excavation hole. A fixing part that is detachably attached to a tremie tube, an arm part extending horizontally from the fixing part, and a penetrating part provided in the arm part and penetrating in the vertical direction. .

The invention of a measuring system is also a measuring system for automatically measuring the height of the top of concrete placed in an excavation hole, which includes a measuring device for measuring the amount of wire to be drawn out, and a measuring device for measuring the amount of wire drawn out from the measuring device. a switching part for reversing the stretching direction of the wire; a first weight attached to the tip of the wire beyond the switching part; and a second weight attached to the middle of the wire above the first weight. It is characterized by

Here, the invention of the measurement system includes a measurement instrument in which a penetration part penetrating in the vertical direction is provided in an arm part extending horizontally from the tremie pipe for placing the concrete, The first weight and the second weight may be arranged below.

Further, the invention of a method for measuring the height of the crown of concrete is a method of measuring the height of the crown of concrete using the above-mentioned measuring instrument, wherein the fixed part of the measuring instrument is connected to the concrete by pouring the concrete. a step of attaching a measuring rope with a weight attached to the tip to a position where the distance from the lower end of the tremie tube is known; a step of placing the weight on the top of the concrete to measure the height of the top; and a step of pulling up the measuring rope that has passed through the penetration part of the measuring instrument and attaching the weight to the top of the concrete. the step of measuring the lower end position of the tremie tube based on the distance when lifting is stopped due to contact of the weight with the tremie tube and the distance of the measuring instrument from the lower end of the tremie tube. shall be.

On the other hand, the invention of a method for measuring the crown height of concrete using the above-mentioned measuring system includes the step of obtaining the distance from the lower end of the tremie pipe for placing the concrete to the measuring instrument; a step of placing a weight on the top of the concrete to measure the height of the top, and winding up the wire passed through the penetration part of the measuring instrument so that the second weight comes into contact with the arm part. The method further comprises the step of measuring the lower end position of the tremie tube based on the distance from the lower end of the tremie tube and the distance of the measuring instrument from the lower end of the tremie tube.

The measuring instrument of the present invention configured as described above includes a fixed part that is detachably attached to a tremie pipe for pouring concrete, and an arm part that extends horizontally from the fixed part. is provided with a penetration portion that penetrates in the vertical direction.

Therefore, the height of the top of concrete can be measured by passing a wire or measuring rope with a weight attached to the tip through the penetration part and letting it land on the top of the concrete. Furthermore, by pulling up the wire passed through the penetration part, measuring the distance when it touches the arm part, and referring to the known distance from the lower end of the tremie tube on the measuring instrument, the lower end position of the tremie tube can be determined. can be easily measured.

FIG. 1 is an explanatory diagram illustrating the configuration of a measurement system according to the present embodiment. FIG. 2 is an explanatory diagram illustrating the configuration of a measuring instrument according to the present embodiment. FIG. 3 is an explanatory diagram of an experiment in which the effects of a two-stage weight and a stepped roller section were confirmed. FIG. 3 is an explanatory diagram of experimental results confirming the effects of a two-stage weight and a stepped roller section. It is a flowchart explaining each step of the measuring method of the top height of concrete of this embodiment. 1 is an explanatory diagram illustrating the configuration of a measurement system of Example 1. FIG. FIG. 7 is an explanatory diagram illustrating how to use the measurement instrument of Example 2. 3 is a flowchart illustrating each step of a method for measuring the top height of concrete in Example 2. FIG.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram illustrating the configuration of a measurement system 1 according to the present embodiment. Further, FIG. 2 is an explanatory diagram illustrating the configuration of the measuring instrument 3 of this embodiment.

When excavating the ground and constructing cast-in-place concrete piles, the excavated hole is filled with a stabilizing fluid (muddy water), and the hydraulic pressure of the stabilizing fluid prevents the wall from collapsing. The tremie pipe 2 is used when concrete is poured into the excavated hole filled with the stabilizing liquid.

For example, as shown in FIG. 1, the lower end 211 of the tremie pipe 2 inserted from the mouth pipe 23 installed near the ground is lowered to the bottom of the excavation hole, and concrete is poured from the input port 221 of the tremie pipe 2. I do. The poured concrete is discharged from the lower end 211 of the tremie pipe 2, and concrete C is thrown up from the bottom of the excavation hole.

When pouring concrete, it is necessary to successively measure and understand the crown height of the poured concrete C, so the crown height is measured as part of construction management. Furthermore, in order to stably cast high-quality concrete without entrainment of stabilizing liquid or the like, it is necessary to reliably embed the lower part of the tremie pipe 2 in the cast concrete C.

Therefore, by using the measuring system 1 of the present embodiment to measure and manage the height of the top of the concrete C and the position of the lower end of the tremie pipe 2, stable placement of high-quality concrete is achieved.

That is, the measurement system 1 of the present embodiment is a device for automatically measuring the height of the top of concrete C placed in an excavation hole, and by incorporating the measuring instrument 3 described later, it is possible to It becomes possible to also measure the lower end position of 2.

Specifically, the measuring system 1 of the present embodiment includes a measuring device 4 that measures the amount of wire 6 drawn out, a converting section 5 that changes the stretching direction of the wire 6 pulled out from the measuring device 4, and a converting section 5. It includes a first weight 71 and a second weight 72 that are attached to the tip of the wire 6 further, and a measurement instrument 3 that is detachably attached to the tremie tube 2.

The measuring device 4 includes a measuring motor 41 that controls the feeding of the wire 6 according to the tension T of the wire 6, a step roller section 42 provided between the measuring motor 41 and the conversion section 5, and a step roller section 42. and a measuring pulley 43 that is provided between the converter 5 and the converter 5 to measure the amount of wire 6 being fed out. Here, the tension T of the wire 6 can be measured, for example, by a load cell attached to the switching section 5.

For example, when the measuring motor 41 detects that the tension T has decreased below a threshold value while the wire 6 is being fed out, winding is started, and after the wire 6 has been wound a certain distance, the measuring motor 41 starts feeding it out again. This is a drum motor that is controlled to switch to It should be noted that control may also be used such that when the tension T of the wire 6 increases above a threshold value, the wire is unrolled, and when the tension T decreases below the threshold value, the wire 6 is wound up.

For example, when the operation button is pressed, the measurement motor 41 operates and the wire 6 is paid out, and when a decrease in the tension T of the wire 6 is detected, such as when the weight hits the bottom, the loose wire 6 is measured. It will be wound up by the motor 41.

On the other hand, the measurement pulley 43 rotates in conjunction with the wire 6 being paid out or wound up. The rotation of the measurement pulley 43 is detected by a coaxial measurement encoder, and the amount of wire 6 to be fed out is calculated in accordance with the detection signal.

The measuring pulley 43 is provided with a V-groove, and is configured to come into close contact with the wire 6 pressed against the measuring pulley 43 by the pressing roller 431, while preventing the generation of frictional force and the wire from coming off. ing.

The stepped roller section 42 provided between the measuring pulley 43 and the measuring motor 41 functions as a moving pulley using a spring and a sliding mechanism, and absorbs fluctuations that occur instantaneously when the wire 6 is fed out or wound up. can be done.

By arranging the pressing roller 431, the slippage between the wire 6 and the measuring pulley 43 can be reduced and the measurement accuracy can be improved. Since this acts in a direction that inhibits the winding, the wire 6 may momentarily become slack when the operation is switched from winding to unwinding.

The stepped roller section 42 is attached between the measuring pulley 43 and the measuring motor 41 for the purpose of removing this slack. In short, by constantly generating tension in the wire 6 using the spring force of the stepped roller portion 42, the instantaneous slack in the wire 6 as described above can be removed, and troubles caused by the wire 6 popping out can be avoided. It becomes possible to reduce the

Specifically, the stepped roller section 42 includes a first pulley 421 disposed on the measurement pulley 43 side, a spring section 423 that applies elastic force when the first pulley 421 slides, and a wire deflected by the first pulley 421. 6 is provided with a second pulley 422 that returns the direction of the measuring motor 41 to the measuring motor 41. That is, the wire 6 that has passed through the first pulley 421 supported by the spring portion 423 is connected to the measurement motor 41 after being bent back by the second pulley 422 and reciprocated.

By adjusting the weight of the second weight 72 and the spring force (spring constant) of the spring part 423, it is possible to absorb the slack of the wire 6 that occurs until the tension T of the wire 6 exceeds the threshold value when it touches the bottom. During this time, the descent of the second weight 72 is suppressed and the measurement pulley 43 does not rotate, so that the accumulation of measurement errors can be reduced.

In this way, between the measuring pulley 43 and the measuring motor 41, there is a mechanism in which tension can be applied by the step roller part 42, and as will be described later, after the first weight 71 touches the bottom, the tension T is reduced and the winding is performed. The slack in the wire 6 between the measuring pulley 43 and the measuring motor 41 can be absorbed until the cutting threshold is exceeded.

In the configuration schematically shown in FIG. 1, the stretching direction of the wire 6 pulled out in the horizontal direction from the measuring device 4 is turned by 90 degrees by the conversion part 5 constituted by a pulley, and then the wire 6 is turned vertically. is directed downward. Note that this angle of direction change is an example, and is not limited to this. The tip of the wire 6 may be turned vertically downward.

A first weight 71 is attached to the tip of the wire 6 beyond the conversion part 5. For example, a weight with a height of about 10 cm and a weight of about 1 kg to 3 kg can be used. Further, a second weight 72 is attached to the middle of the wire 6 above the first weight 71.

Here, although it is expressed as being in the middle of the wire 6, the wire material connected to the second weight 72 is different from the connecting wire 61 connecting between the first weight 71 and the second weight 72. It may be. In this embodiment, the lower end of the connecting line 61 and the tip of the wire 6 refer to the same thing. The length from the bottom surface of the first weight 71 to the upper end of the second weight 72 across the connecting line 61 is measured in advance.

The second weight 72 is provided to prevent the tension T of the wire 6 from suddenly decreasing and causing slack when the first weight 71 reaches the bottom. In short, by constantly maintaining the tension of the wire 6 with the second weight 72, it is possible to prevent the measurement pulley 43 from idling, the wire 6 from becoming tangled, and a decrease in measurement performance. The second weight 72 can be a weight that is lighter than the first weight 71 and has a weight that can apply a downward tension T to the wire 6 even when receiving the buoyancy of the stabilizing liquid.

FIG. 2 is a diagram illustrating the configuration of the measurement instrument 3 of this embodiment as an example. As shown in FIGS. 1 and 2, the measuring instrument 3 of this embodiment includes a fixed part 31 that is detachably attached to the tremie pipe 2 for pouring concrete, and a fixed part 31 that extends horizontally from the fixed part 31. It includes an arm portion 32 and a penetrating portion 33 provided on the arm portion 32 and penetrating in the vertical direction.

The fixing portion 31 includes, for example, a ring-shaped band 311 surrounding the outer periphery of the tremie tube 2, and a base 312 that is the starting point and ending point of the ring-shaped band 311. The tremie pipe 2 is constructed by adding unit lengths of pipe material according to the length (depth) of the excavation hole. FIG. 1 shows an example of an upper pipe 22 in which a concrete input port 221 is installed at the upper end, and a leading pipe 21 serving as the lower end 211 of the tremie pipe 2, but between the upper pipe 22 and the leading pipe 21, Depending on the length of the excavation hole and the height of the top of the concrete C, a necessary number of pipes of unit length are interposed.

The fixing part 31 is detachably attached to, for example, the upper part of the front tube 21. When the fixing part 31 is attached to the front tube 21, the distance from the lower end 211 is measured and recorded as the known dimension L.

The length of the arm portion 32 extending from the fixed portion 31 in a direction (horizontal direction) perpendicular to the axial direction of the tremie tube 2 can be set arbitrarily. Since FIG. 1 is a schematic diagram for explanation, the explanation will be made with reference to FIG. 2.

The arm portion 32 extends from the base 312 of the fixed portion 31, for example. A penetrating portion 33 is provided, for example, at the tip of the arm portion 32. The penetrating portion 33 penetrates in a direction perpendicular to the extending direction of the arm portion 32, and when the arm portion 32 is oriented in the horizontal direction, the penetrating portion 33 penetrates in the vertical direction.

Although FIG. 2 shows the through-hole 33 having a circular through-hole, the present invention is not limited to this. The penetrating portion 33 only needs to have an inner space larger than the outer diameter of the wire 6 and be formed in a shape through which the upper end of the second weight 72 cannot pass, so the shape of the inner space is not limited to a circular shape. , it may be an elongated rectangular slit. Further, a penetrating portion 33 may be provided in the middle of the arm portion 32.

The penetrating portion 33 illustrated in FIG. 2 is formed into a C-shape in plan view, and a gate 331 that opens and closes with a spring is provided in the open portion. That is, by pushing the gate 331, the wire 6 can be passed from the side into the interior of the penetrating portion 33.

This measuring instrument 3 is attached to the tremie tube 2 in order to measure the lower end position of the tremie tube 2. The details of the measurement method will be described later, but after measuring the height of the top of the concrete C, the wire 6 is wound up and the second weight 72 is brought into contact with the penetration part 33 of the arm part 32, and the distance at that time is measured. This makes it possible to determine the lower end position of the tremie tube 2.

Here, an experiment in which the effects of the two-stage weight constituted by the first weight 71 and the second weight 72 and the step roller section 42 of the measuring device 4 were confirmed will be described with reference to FIGS. 3 and 4.

FIG. 3 is an explanatory diagram of an experiment in which the effects of the two-stage weight and the stepped roller section 42 were confirmed. In the experiment, a 1 kg weight was used as the first weight 71, and a 600 g weight was used as the second weight 72. The first weight 71 and the second weight 72 were connected by a spring.

Although not shown in FIG. 3, the measuring device 4 to which the wire 6 extending upward from the second weight 72 is connected is equipped with the stepped roller section 42 described above, and for comparison, the measuring device 4 has a stepped roller section. A device without 42 was used.

In the experiment, the tension T measured while winding down the wire 6 and lowering the first weight 71 was about 16N. Even when the bottom surface of the first weight 71 landed on the concrete specimen and the tension T decreased, the tension T of approximately 6N to 8N was maintained as shown in the right diagram of FIG. 3. If the tension of the wire 6 can be maintained at all times by the second weight 72 in this way, it becomes possible to prevent the measurement pulley 43 from idling and the wire 6 from becoming tangled.

On the other hand, FIG. 4 is an explanatory diagram of the results of an experiment in which the effects of the two-stage weight and the stepped roller section 42 were confirmed. In FIG. 4, the horizontal axis shows time, the vertical axis on the left side of each graph shows the wire tension (N), and the vertical axis on the right side of each graph shows the wire payout amount (m). The solid line drawn in a wavy shape indicates the fluctuation in tension, and the dashed-dotted line drawn linearly indicates the amount of wire payout, so by comparing the two, it is possible to understand the correlation between the two.

The graph on the left side of FIG. 4 shows the results of measurement using a device without a step roller section 42 using a two-step weight. Looking at this figure, it can be seen that the amount of wire drawn out increased even after it hit the bottom, and winding started 0.15 seconds after it hit the bottom. Although the tension T decreased from about 23 N before hitting the bottom to about 5 N after hitting the bottom, it was confirmed that the wire 6 did not become tangled and measurements could be continued.

On the other hand, the graph on the right side of FIG. 4 shows the results of measurement using the measuring device 4 with the step roller section 42 using a two-step weight. Looking at this figure, it can be seen that the amount of wire being fed out stops when it hits the bottom, and that the fluctuations in the tension T after it hits the bottom are also stable.

That is, by providing the stepped roller portion 42 in the measuring device 4, it becomes possible to absorb the amount of the wire 6 fed out which varies greatly upon bottoming. Then, absorption of the amount of feeding by the stepped roller portion 42 suppresses fluctuations in the tension T, making it possible to stabilize measurement. In addition, since excessive unrolling and winding after landing on the bottom can be suppressed, measurement accuracy can also be improved.

Next, a method for measuring the height of the top of concrete according to the present embodiment will be explained. FIG. 5 is a flowchart illustrating the flow of the method for measuring the height of the top of concrete according to the present embodiment.

First, in step S1, the measurement instrument 3 is attached to the tremie tube 2. The tremie pipe 2 needs to be long enough for the lower end 211 to reach the bottom of the excavation hole at the beginning of concrete pouring. The measurement instrument 3 is attached to a leading tube 21 located at the most distal end of the tremie tube 2.

For example, as shown in FIG. 1, the fixing part 31 of the measuring instrument 3 is fixed by wrapping a band 311 just below the joint part at the upper end of the leading tube 21. The distance between the fixed part 31 and the lower end 211 of the top tube 21 is measured using a measuring tape or the like and recorded as a known dimension L.

Subsequently, in step S2, the measurement system 1 is set. The wire 6 is passed through the penetration part 33 of the measurement instrument 3 attached to the front tube 21 so that the first weight 71 and the second weight 72 are arranged below the arm part 32.

A length of pipe material is added above the leading pipe 21 in accordance with the length of the excavation hole so that the input port 221 can be placed on the ground. The tremie tube 2 is suspended in the excavation hole by supporting the upper tube 22 on a horizontal member or the like extending over the upper end of the mouth tube 23.

Although the reference height that serves as a reference for measurement can be set at any position, here, the height (position) of the upper end of the mouth tube 23 is set as the reference height. In the measurement system 1, the distance from the reference height to, for example, the bottom surface of the first weight 71 is measured. In the following, the height of the top of concrete refers to the distance D1 between the position of the top of concrete C and the reference height, and the lower end position of the tremie pipe 2 refers to the distance D2 between the lower end 211 of the top pipe 21 and the reference height. refers to

The wire 6 extending in the vertical direction above the mouth tube 23 is turned, for example, in the horizontal direction at the conversion part 5, passes through the measurement pulley 43 and the stepped roller part 42, and is connected to the measurement motor 41. This makes it possible to measure the height of the top of the concrete C and the position of the bottom of the tremie pipe 2.

Note that by performing measurement using the measurement system 1 before pouring concrete, the depth of the bottom of the excavation hole (excavation depth) and the connection length of the tremie pipe 2 can be confirmed. By performing such measurements before pouring, it is possible to check for human errors such as incorrect management of the excavation depth, incorrect connection of the tremie pipe 2, and incorrect measurement of the known dimension L.

Concrete is charged through an input port 221 of a hopper installed at the upper end of the tremie pipe 2, and is discharged from the lower end 211 to the bottom of the hole. The lower end 211 of the tremie pipe 2 is managed so that a length of 2 m or more is buried in the concrete C, for example, so that impurities such as stabilizing liquid and slime are not caught in the poured concrete C.

The top of the concrete C that is ejected from the bottom of the excavation hole gradually rises as the concrete is poured. Therefore, the height of the top of the concrete C is measured at the timing set for construction management (step S3).

In the measurement system 1, the measurement of the concrete crown height is automatically performed. That is, at a set timing after the start of concrete placement, the measuring motor 41 is activated to let out the wire 6 and lower the first weight 71 into the stabilizing liquid in the excavation hole. Here, the first weight 71 and the second weight 72 each have a weight that allows them to fall naturally even when subjected to buoyancy in the stable liquid.

Until the first weight 71 touches the top of the concrete C, tension T is generated in the wire 6 due to the downward force acting in the stabilizing liquid based on the weight of the first weight 71 and the second weight 72. The tension T while the measuring motor 41 rotates and the wire 6 is fed out is constantly measured by a load cell in the conversion section 5.

When the first weight 71 that continues to descend reaches the bottom of the concrete C, the tension T of the wire 6 decreases (see the right diagram in FIG. 4). Since the measurement system 1 of the present embodiment includes the two-stage weight and the step roller section 42, stable measurement is continued without sudden fluctuations even when the user lands on the bottom. Then, a decrease of the tension T by more than a set value is detected as bottoming, and the height of the top of the concrete C (distance D1 between the reference height and the top) is measured.

When the measurement of the top height is completed, the measurement motor 41 rotates and winding of the wire 6 is started in step S4. When the wire 6 is wound up, the first weight 71 and the second weight 72 begin to rise.

When the upper end of the second weight 72 contacts the arm portion 32 of the measuring instrument 3, the tension T of the wire 6 increases, so that the contact can be detected and the distance at that point can also be obtained. That is, since the length from the bottom of the first weight 71 to the top of the second weight 72 is a known value, the distance from the value measured based on the bottom of the first weight 71 to the top of the second weight 72 is a known value. By subtracting the length, the distance D3 between the reference height and the arm portion 32 can be measured.

Therefore, in step S5, the lower end position of the tremie tube 2 is calculated. As shown in FIG. 1, the measurement distance D3 is measured by the measuring instrument 3 and the wire 6 in step S4. On the other hand, the distance between the measuring instrument 3 and the lower end position of the tremie tube 2 is a known dimension L. Therefore, by adding the known dimension L to the measured distance D3, the distance D2 indicating the lower end position of the tremie tube 2 can be determined.

As the concrete placement progresses and the top rises, the tremie pipe 2 is successively pulled up, and the pipe material that has been added between the top pipe 21 and the upper pipe 22 is removed each time. Even during such lifting work of the tremie tube 2, the lower end position of the tremie tube 2 needs to be buried in the concrete C, so the lower end position of the tremie tube 2 is managed.

Next, the operation of the measuring instrument 3, the measuring system 1, and the method for measuring the top height of concrete according to the present embodiment will be explained.
The measuring system 1 of the present embodiment configured as described above includes a measuring instrument 3 that is detachably attached to a tremie pipe 2 for pouring concrete, a measuring device 4 that measures the amount of wire being fed out, It includes a first weight 71 and a second weight 72 attached to the tip of the wire 6.

The measuring device 4 controls the feeding of the wire 6 as the tension T of the wire 6 decreases, and automatically measures the top height of the concrete C from the reference height by measuring the amount of feeding. Can be done.

That is, when the first weight 71 at the tip of the wire 6 bottoms out on the top of the concrete C, the tension T decreases, so the height of the top of the concrete C is calculated from the amount of feeding measured by the measuring device 4 at that time. can be found.

Further, since the second weight 72 is attached to the wire 6 above the first weight 71 for bottoming out, the tension T of the wire 6 is maintained according to the weight of the second weight 72 even after the wire 6 bottoms out. This prevents the measurement pulley 43 from spinning idly and the wire 6 from becoming tangled, thereby preventing deterioration in measurement performance.

Furthermore, by interposing the step roller part 42 between the measurement pulley 43 that measures the amount of feedout and the measurement motor 41, it becomes possible to absorb sudden movements in and out of the wire 6 and bending of the wire 6. The stability of measurement according to 4 can be improved.

Further, since the extra wire 6 that does not need to be measured is absorbed by the stepped roller portion 42, unnecessary detection values are prevented from being accumulated in the encoder of the measurement pulley 43, and measurement accuracy is improved. Can be done.

The measuring instrument 3 includes a fixing part 31 that is detachably attached to the tremie pipe 2 for pouring concrete, and an arm part 32 that extends horizontally from the fixing part 31. is provided with a penetration portion 33 that penetrates in the vertical direction.

As described above, the height of the top of the concrete C can be measured by passing the wire 6 having the first weight 71 attached to the tip thereof through the penetrating portion 33 and letting it land on the top of the concrete C. Furthermore, the lower end position of the tremie tube 2 can be easily measured by winding up the wire 6 passed through the penetration part 33 and measuring the distance D3 when the second weight 72 contacts the arm part 32.

In short, by simply attaching the measuring instrument 3 to the tremie pipe 2 and knowing the known dimension L of the measuring instrument 3 from the lower end 211 of the tremie pipe 2, one measuring device 4 can measure the height of the top of the concrete C. It becomes possible to reliably manage two measurement values: the position and the lower end position of the tremie tube 2.

Hereinafter, a measurement system 1A different from the measurement system 1 of the embodiment described above will be described with reference to FIG. 6. Note that parts that are the same or equivalent to those described in the above embodiment will be described using the same terms or the same symbols.

In FIG. 1 of the embodiment, the case where the wire 6 is suspended in the excavation hole from the conversion part 5 fixed at one location above the mouth pipe 23 has been described as an example. In the first embodiment, a measurement system 1A that can arbitrarily change the plane position for measuring the height of the top of concrete C will be described.

In the measurement system 1A of the first embodiment, a dropping position adjustment tool 8 for the wire 6 is installed at the upper end of the mouth tube 23. The dropping position adjuster 8 includes a conversion pulley 81 that changes the direction of the wire 6 extended from the measuring device 4, and a conversion section 5A that changes the direction of the wire 6 that has been horizontally extended through the conversion pulley 81 in the vertical direction. It is equipped with

The conversion section 5A constituted by a pulley can be moved along the drop position adjustment tool 8 that extends in the horizontal direction. The conversion part 5A that has been moved to the desired position of the drop position adjustment tool 8 is fixed at that arbitrary position. Note that when the conversion section 5A is moved, the payout distance of the wire 6 will also change, so the measuring device 4 will be calibrated (origin reset) each time.

On the other hand, the measuring instrument 3A attached to the tremie tube 2 is also provided with an elongated slit-shaped penetrating portion 33A extending in the extending direction in the arm portion 32A. Therefore, the wire 6 passed through the penetrating portion 33A of the arm portion 32A can change its position as the conversion portion 5A moves on the drop position adjustment tool 8.

With the measurement system 1A of the first embodiment configured as described above, the plane position at which the height of the top of the concrete C is measured can be arbitrarily set. Therefore, the height of the top of the concrete C at any location, such as near the tremie pipe 2, a little distance from the tremie pipe 2, or near the wall of an excavation hole, can be determined at any time. Become.

Note that the other configurations and effects are substantially the same as those of the embodiment or other examples, so description thereof will be omitted.

Hereinafter, a method of using the measurement instrument 3 that is different from the embodiment described above will be described with reference to FIGS. 7 and 8. Note that parts that are the same or equivalent to those described in the embodiment or Example 1 will be described using the same terminology or the same reference numerals.

In the second embodiment, a case will be described in which automatic measurement by the measuring device 4 is not performed. That is, regarding the case where a worker attaches the measuring instrument 3 to the tremie pipe 2 and measures the top height of the concrete C and the lower end position of the tremie pipe 2 using the measuring rope 9 with a weight 91 attached to the tip. explain.

FIG. 8 is a flowchart illustrating the flow of the method for measuring the top height of concrete according to the second embodiment.
First, in step S11, the measurement instrument 3 is attached to the tremie tube 2. The distance between the fixed part 31 of the measuring instrument 3 and the lower end 211 of the front tube 21 is measured with a measuring tape or the like and recorded as a known dimension L.

Subsequently, in step S12, the measuring rope 9 is passed through the penetrating portion 33 of the measuring instrument 3 attached to the front tube 21 so that the weight 91 is disposed below the arm portion 32. The measuring rope 9 is provided with a scale in units of, for example, 10 cm so that the distance from the weight 91 can be measured.

After the concrete placement begins and the top of the concrete C starts rising, a worker holding the top end of the measuring rope 9 performs measurement. The worker slowly lowers the weight 91 suspended in the stabilizing liquid.

While the weight 91 is descending through the stabilizing liquid, the worker feels a certain tension, and when the weight 91 touches the top of the concrete C, the worker feels that the tension has suddenly decreased. Can be done. Therefore, the distance D1 at that time is read on the scale of the measuring rope 9, and is determined as the height of the top of the concrete C (step S13).

When the measurement of the top height is completed, the worker pulls up the measuring rope 9 and raises the weight 91 in step S14. When the upper end of the weight 91 comes into contact with the arm portion 32 of the measuring instrument 3, the lifting of the measuring rope 9 is stopped and the distance at that point is measured by reading the scale on the measuring rope 9. That is, the distance D3 between the reference height and the arm portion 32 is measured.

Therefore, in step S15, the lower end position of the tremie tube 2 is calculated. As shown in FIG. 7, the measurement distance D3 is measured in step S14 by measurement using the measuring instrument 3 and the measuring rope 9. On the other hand, the distance between the measuring instrument 3 and the lower end position of the tremie tube 2 is a known dimension L. Therefore, by adding the known dimension L to the measured distance D3, the distance D2 indicating the lower end position of the tremie tube 2 can be determined.

With the measuring instrument 3 and concrete crown height measuring method of the second embodiment configured as described above, two measurements, the crown height of the concrete C and the lower end position of the tremie pipe 2, can be made even by manual measurement. Values can be managed reliably.

Note that the other configurations and effects are substantially the same as those of the embodiment or other examples, so description thereof will be omitted.

The embodiments of the present invention have been described above in detail with reference to the drawings, but the specific configuration is not limited to this embodiment or example, and design changes can be made as long as they do not depart from the gist of the present invention. are included in the present invention.

For example, in the embodiments and examples described above, a case has been described in which both the top height of concrete C and the bottom end position of tremie pipe 2 are measured using measurement systems 1 and 1A and measurement instrument 3. However, the measurement system 1, 1A can also measure and manage only the height of the top of the concrete C.

1: Measurement system 2: Tremy tube 211: Lower end 3: Measuring instrument 31: Fixed part 32: Arm part 33: Penetrating part 4: Measuring device 41: Measuring motor 42: Step roller part 43: Measuring pulley 5: Conversion Part 6 : Wire 71 : First weight 72 : Second weight 1A : Measurement system 3A : Measuring instrument 32A : Arm part 33A : Penetrating part 5A : Conversion part 8 : Drop position adjustment tool 9 : Measurement rope 91 : Weight C : Concrete T : Tension

Claims (7)

A measuring instrument used to measure the height of the top of concrete poured into an excavation hole,
a fixing part that is detachably attached to the tremie pipe for pouring the concrete;
an arm portion extending horizontally from the fixed portion;
A measuring instrument comprising: a penetration part provided in the arm part and penetrating in the vertical direction. A measurement system for automatically measuring the height of the top of concrete placed in an excavation hole,
A measuring device that measures the amount of wire being fed out;
a conversion part that turns the stretching direction of the wire pulled out from the measuring device;
a first weight attached to the tip of the wire beyond the conversion part;
A measurement system comprising: a second weight attached to the middle of the wire above the first weight. comprising a measuring instrument provided with a penetration part that penetrates in the vertical direction on an arm part that extends horizontally from the tremie pipe for placing the concrete,
The measurement system according to claim 2, wherein the first weight and the second weight are arranged below the measurement instrument. 4. The measuring system according to claim 2, wherein the measuring device includes a stepped roller part that reciprocates in the stretching direction of the wire. The measurement system according to claim 2 or 3, wherein the conversion section is movable in a horizontal direction along a drop position adjustment tool. A method for measuring the height of the top of concrete using the measuring instrument according to claim 1, comprising:
attaching the fixed part of the measuring instrument to a position where the distance from the lower end of the tremie pipe for placing the concrete is known;
passing a measuring rope with a weight attached to its tip through the penetration part such that the weight is located below the measuring instrument;
a step of placing the weight on the top of the concrete and measuring the height of the top;
The distance from the lower end of the tremie tube of the measuring instrument when the measuring rope that has passed through the penetration part of the measuring instrument is pulled up and the lifting stops when the weight comes into contact with the arm part; A method for measuring the height of the top of concrete, comprising the step of measuring the bottom end position of the tremie pipe based on the distance. A method for measuring the height of the top of concrete using the measuring system according to claim 3, comprising:
obtaining the distance from the lower end of the tremie pipe for placing the concrete to the measuring instrument;
a step of placing the first weight on the top of the concrete and measuring the height of the top;
The wire passed through the penetration part of the measurement instrument is wound up, and the second weight contacts the arm part based on the distance and the distance of the measurement instrument from the lower end of the tremie tube. A method for measuring the height of the top of concrete, comprising the step of measuring the position of the bottom of a tremie pipe.