JP7687614B2 - Concrete pumping pump, concrete pumpability evaluation test device, concrete pumping method, and concrete pumpability evaluation test method - Google Patents

Description

The present invention relates to a concrete pump, a concrete pumpability evaluation test device, a concrete pumping method, and a concrete pumpability evaluation test method.

Conventionally, a concrete pumping method using a pressure pump is known as a method for transporting concrete to a construction site when constructing various structures such as buildings, slopes, retaining walls, and tunnels. In the concrete pumping method, concrete is sent from a concrete pressure pump mounted on a pump truck through a pressure pipe to the construction site of a building and poured, as shown in Patent Document 1, for example.

A typical concrete pump is configured as shown in Patent Document 2, for example, in which a pair of plunger pumps are fixed to a sliding plate with two through holes, and the sliding plate is moved back and forth horizontally relative to a fixed plate with three through holes. Of the three through holes in the fixed plate, the two at both ends are connected via suction pipes to a hopper in which concrete is stored, and the central through hole is connected to a discharge pipe that sends concrete to the pressure pipe. The concrete pump can repeat the process in which one plunger sucks concrete from the hopper while the other plunger simultaneously sends concrete to the discharge pipe, and then moves horizontally, after which one plunger simultaneously sends concrete to the discharge pipe and the other plunger sucks concrete from the hopper.

The Japan Society of Civil Engineers has guidelines for testing methods to evaluate the pumpability of concrete using a concrete pump (Non-Patent Document 1). When pouring concrete by pumping over long distances, the guidelines stipulate that the actual piping test should be carried out by connecting the pipes that will actually be used to install a long piping route.

Japanese Patent Application Publication No. 11-131807 JP 2006-200547 A

Concrete Committee, "Guidelines for Concrete Pumping" [2012 Edition], Japan Society of Civil Engineers, June 2012

However, the concrete pump in Patent Document 2 required horizontal space to allow a pair of plungers to move back and forth through three horizontally arranged through holes.

In addition, actual piping tests such as those described in Non-Patent Document 1, which are test methods for evaluating the pumpability of concrete, can cost hundreds of millions to tens of millions of yen for a single test, including the pump truck used in the test, the piping costs, and the disposal costs of the concrete used in the test.

Therefore, an object of the present invention is to provide a concrete pump and a method for pumping concrete that can save space.Another object of the present invention is to provide a concrete pumpability evaluation test device and a concrete pumpability evaluation test method that can save space and reduce costs.

The present invention has been made to solve at least some of the problems described above, and can be realized in the following aspects or application examples.

[1] One aspect of the concrete pump according to the present invention is
a fixed base having a first opening and a second opening;
A rotating plate that is rotatable about a rotation axis relative to the fixed base;
A drive mechanism for rotating the rotary plate;
Two cylinders fixed to the rotating plate at equal distances from the rotation axis;
Two plungers each moving back and forth within the two cylinders;
Equipped with
the two cylinders can be alternately connected to the first opening and the second opening by rotating the rotary plate using the drive mechanism;
By retracting the plunger in the cylinder connected to the first opening, concrete can be poured into the cylinder through the first opening,
a concrete pump capable of discharging concrete contained in the cylinder by advancing the plunger in the cylinder connected to the second opening;
a pipe having one end connected to the first opening and the other end connected to the second opening;
Equipped with
The two cylinders are alternately connected to the first opening and the second opening, thereby enabling concrete to be circulated from the second opening to the first opening .

[ 2 ] One aspect of the concrete pumpability evaluation test method according to the present invention is
a first pumping step of discharging concrete in a second cylinder connected to a second opening formed in a fixed base into a pipe having one end connected to the second opening, and sucking concrete from the pipe having the other end connected to a first opening formed in the fixed base into a first cylinder connected to the first opening;
a first rotation step of rotating a rotary plate to which the first cylinder and the second cylinder are fixed relative to the fixed base to connect the first cylinder to the second opening and connect the second cylinder to the first opening after the first pressure-feeding step;
a second pumping step of discharging the concrete in the first cylinder through the second opening into the piping and sucking the concrete from the piping into the second cylinder;
a second rotation step of rotating the rotary plate relative to the fixed base after the second pumping step to connect the first cylinder to the first opening and connect the second cylinder to the second opening;
The above steps are repeated to circulate the concrete from the second opening to the first opening until the inside of the pipe becomes clogged.

According to one aspect of the concrete pump and one aspect of the concrete pumping method of the present invention, it is possible to achieve space saving. Furthermore, according to one aspect of the concrete pumpability evaluation test device and one aspect of the concrete pumpability evaluation test method of the present invention, it is possible to achieve cost reduction while saving space.

1 is a plan view of a concrete pump according to an embodiment of the present invention, partially shown in cross section. FIG. 2 is a cross-sectional view taken along line AA of FIG. 1. 4 is a flowchart of a method for pumping concrete according to the present embodiment. FIG. 2 is a schematic diagram illustrating a method for pumping concrete according to the present embodiment. FIG. 2 is a schematic diagram illustrating a method for pumping concrete according to the present embodiment. FIG. 2 is a schematic diagram illustrating a method for pumping concrete according to the present embodiment. FIG. 2 is a schematic diagram illustrating a method for pumping concrete according to the present embodiment. FIG. 2 is a schematic diagram illustrating a method for pumping concrete according to the present embodiment. FIG. 2 is a plan view of a concrete pumpability evaluation test device according to the present embodiment, partially shown in cross section. 1 is a flowchart of a test method for evaluating pumpability of concrete according to the present embodiment. FIG. 2 is a schematic diagram illustrating a concrete pumpability evaluation test method according to the present embodiment. FIG. 2 is a schematic diagram illustrating a concrete pumpability evaluation test method according to the present embodiment. FIG. 2 is a schematic diagram illustrating a concrete pumpability evaluation test method according to the present embodiment. FIG. 2 is a schematic diagram illustrating a concrete pumpability evaluation test method according to the present embodiment.

Below, preferred embodiments of the present invention will be described in detail with reference to the drawings. Note that the embodiments described below do not unduly limit the content of the present invention described in the claims. Furthermore, not all of the configurations described below are necessarily essential components of the present invention.

The concrete pump of this embodiment comprises a fixed base having a first opening and a second opening, a rotating plate that can rotate around a rotation axis relative to the fixed base, a drive mechanism for rotating the rotating plate, two cylinders fixed to the rotating plate at positions equidistant from the rotation axis, and two plungers that move forward and backward within the two cylinders, respectively, and is characterized in that the two cylinders can be alternately connected to the first opening and the second opening by rotating the rotating plate with the drive mechanism, concrete can be accommodated in the cylinder through the first opening by retracting the plunger in the cylinder connected to the first opening, and the concrete accommodated in the cylinder can be discharged by advancing the plunger in the cylinder connected to the second opening.

The concrete pumpability evaluation test device according to this embodiment is characterized by comprising the concrete pump and a pipe having one end connected to the first opening and the other end connected to the second opening.

1. Concrete pump A concrete pump 10 according to one embodiment of the present invention will be described with reference to Figures 1 and 2. Figure 1 is a plan view of the concrete pump 10 according to this embodiment, partly in cross section, and Figure 2 is a cross-sectional view taken along line A-A in Figure 1.

As shown in Figures 1 and 2, the concrete pump 10 includes a fixed base 20 that is installed, for example, on a pump vehicle, a rotating plate 30, a drive mechanism 31, two cylinders (first cylinder 41, second cylinder 51) fixed to the rotating plate 30, two plungers (first plunger 42, second plunger 52) that move back and forth within the two cylinders, and a control device 60.

The fixed base 20 has a first opening 21 and a second opening 22 that penetrate the fixed base 20 in a direction along the rotation axis 35. The fixed base 20 is plate-shaped with the rotating plate 30 in contact with one side, and has a base at the lower end for installation on a pump vehicle or the like. The first opening 21 that opens on the other side of the fixed base 20 is connected to a first pipe 24, and the second opening 22 is connected to a second pipe 25. The shape of one side of the fixed base 20 only needs to have a flat surface that maintains a state in which the through hole of the rotating plate 30 is blocked during rotation, and is not limited to a rectangular shape as shown in FIG. 2, but may be a disk shape, for example.

One end of the first pipe 24 is fixed to the fixed base 20, and the other end is connected to the hopper 23 that contains concrete. One end of the second pipe 25 is fixed to the fixed base 20, and the inside is connected to the through hole of the rotating plate 30 connected to the second opening 22 and the cylinder via the second opening 22. The length of the second pipe 25 varies depending on the construction site, and is, for example, several tens of meters. In this specification, "concrete" refers to fresh concrete containing cement, sand, gravel, and water, but does not exclude cement and mortar. The concrete in the hopper 23 passes through the first pipe 24, is sucked into one of the first cylinder 41 or the second cylinder 51 via the first opening 21, and is discharged from the other side to the second pipe 25 via the second opening 22. In other words, only two pipes, the first pipe 24 for suction and the second pipe 25 for discharge, are connected to the concrete pump 10, and two pipes for suction are not required as in the conventional method.

The rotating plate 30 can rotate around the rotation axis 35 relative to the fixed base 20. The rotation axis 35 is a virtual line extending from the rotation axis of the rotating plate 30, and in the example of Figs. 1 and 2, it extends horizontally perpendicular to the rotating plate 30. The rotating plate 30 is approximately disk-shaped and is supported rotatably around an axis protruding from the fixed base 20 at the position of the central rotation axis 35. The rotating plate 30 has two through holes formed at a predetermined distance from the rotation axis 35. The centers of both through holes and the rotation axis 35 are located on the same virtual plane (horizontal plane in Figs. 1 and 2). Each through hole communicates with the first opening 21 and the second opening 22 at the rotation stop position of the rotating plate 30 (position in Figs. 1 and 2). Therefore, the through holes formed in the rotating plate 30 and the fixed base 20, together with the first pipe 24 and the second pipe 25, form part of the flow path through which the concrete flows.

The drive mechanism 31 rotates the rotating plate 30 around a rotation axis 35 relative to the fixed base 20. Any known drive mechanism can be used as the drive mechanism 31 as long as it is capable of rotating the rotating plate 30. In this embodiment, the drive mechanism 31 is an example of a rack and pinion. The drive mechanism 31 can rotate the pinion gear 34 meshing with the rack 33 forward and backward by 180 degrees at a time as the rotation hydraulic cylinder 32 moves the rack 33 forward and backward.
Since a rack and pinion is used as the rotor 1, it is assumed that the rotor 1 rotates in both directions. However, if an electric motor is used, the rotor 1 may rotate in only one direction.

The first cylinder 41 and the second cylinder 51 have the same cylinder volume for accommodating a predetermined amount of concrete inside. The first cylinder 41 and the second cylinder 51 have the same shape. The first cylinder 41 and the second cylinder 51 can suck and discharge concrete by the first plunger 42 and the second plunger 52 that can move back and forth inside. The two cylinders (the first cylinder 41 and the second cylinder 51) are fixed to the rotating plate 30 at one end at a position equidistant from the rotation axis 35. The two cylinders (the first cylinder 41 and the second cylinder 51) are fixed to the mounting plate 40 that is arranged opposite the rotating plate 30 at the other end. The first cylinder 41 is fixed at a position communicating with one of the through holes of the rotating plate 30, and is arranged in a straight line from the first piping 24 through the first opening 21 to the first cylinder 41 in the rotation stop position in Figures 1 and 2. In addition, the second cylinder 51 is fixed at a position communicating with the other through hole of the rotating plate 30, and is arranged in a straight line from the second pipe 25 through the second opening 22 to the second cylinder 51 in the rotation stop position in FIG. 1 and FIG. 2. The two cylinders (the first cylinder 41 and the second cylinder 51) can be alternately connected to the first opening 21 and the second opening 22 by rotating the rotating plate 30 with the driving mechanism 31. Therefore, the state in which the first cylinder 41 is connected to the first opening 21 and the second cylinder 51 is connected to the second opening 22, and the state in which the second cylinder 51 is connected to the first opening 21 and the first cylinder 41 is connected to the second opening 22 can be alternately switched by rotation. The connection between each cylinder and the first opening 21 or the second opening 22 may be in a state in which the concrete contained therein is in communication so that it can flow, and each cylinder and the opening are also connected through the through holes of the fixed base 20 and the rotating plate 30 as in this embodiment.

At the rotation stop position, the central axes of the first cylinder 41 and the second cylinder 51 are parallel to the rotation axis 35 and lie on an imaginary plane (a horizontal plane in this example) through which the rotation axis 35 passes, with the first cylinder 41 positioned at 0 degrees and the second cylinder 51 positioned at 180 degrees around the rotation axis 35. At the rotation stop position, the first cylinder 41 and the second cylinder 51 are not limited to being on a horizontal plane, but may be in a plane inclined relative to the horizontal plane to match the positions of the first pipe 24 and the second pipe 25.

The first plunger 42 is disposed inside the first cylinder 41, and can be moved forward and backward in a direction along the rotation axis 35 by a first hydraulic cylinder 43 fixed to the mounting plate 40. The second plunger 52 is disposed inside the second cylinder 51, and can be moved forward and backward in a direction along the rotation axis 35 by a second hydraulic cylinder 53 fixed to the mounting plate 40. The mounting plate 40, the first hydraulic cylinder 43, and the second hydraulic cylinder 53 rotate together with the first cylinder 41 and the second cylinder 51 around the rotation axis 35 as the rotating plate 30 rotates. The drive mechanism for moving the first plunger 42 and the second plunger 52 forward and backward is not limited to hydraulic cylinders, and any known drive mechanism can be used.

The control device 60 includes a memory unit 62 for storing, for example, a control program, sensors 65 and the like installed in each part of the concrete pump 10, a calculation unit 61 for receiving information from the sensors 65 and the like and performing various calculations based on the control program, an interface (not shown) for outputting commands to each drive unit based on the calculation results, and a hydraulic pump and hydraulic circuit (not shown). The calculation unit 61 is composed of a CPU, and the memory unit 62 is composed of a RAM, a ROM, and the like. The sensor 65 is, for example, a magnetic proximity switch, and the calculation unit 61 can measure the number of discharges to the second pipe 25 based on a signal from the sensor 65 that detects the forward movement of the second plunger 52. Although only one sensor 65 is shown in FIG. 1, a sensor is also provided in the first cylinder 41. In addition to the sensor 65, multiple sensors are installed in the concrete pump 10, and may be provided with, for example, a strain gauge sensor, an acceleration sensor, a flow meter, and the like. The hydraulic pump and hydraulic circuit supply hydraulic oil to the rotary hydraulic cylinder 32, the first hydraulic cylinder 43, and the second hydraulic cylinder 53. The control device 60 may further include a display device such as a liquid crystal panel and an input device operated by an operator.

The concrete pump 10 can simultaneously drive the first hydraulic cylinder 43 and the second hydraulic cylinder 53 in response to a command from the control device 60 to retract the plunger (first plunger 42 in FIG. 1) in the cylinder (first cylinder 41 in FIG. 1) connected to the first opening 21, thereby storing concrete in the cylinder, and can advance the plunger (second plunger 52 in FIG. 1) in the cylinder (second cylinder 51 in FIG. 1) connected to the second opening 22 to discharge the concrete stored in the cylinder. In addition, the concrete pump 10 that has completed suction and discharge of concrete can drive the drive mechanism 31 in response to a command from the control device 60 to rotate the rotating plate 30 180 degrees relative to the fixed base 20, thereby switching the positions of the first cylinder 41 and the second cylinder 51. More specific operations of the concrete pump 10 will be described later.

In this way, the concrete pump 10 according to this embodiment requires one less connection path with the hopper 23 compared to conventional pumps, and because the two cylinders do not move horizontally, the installation area is smaller, realizing space savings.

2. Concrete Pumping Method A method for pumping concrete 12 according to one embodiment of the present invention will be described with reference to Figs. 1 to 8. Fig. 3 is a flow chart of the method for pumping concrete 12 according to this embodiment, and Figs. 4 to 8 are schematic diagrams for explaining the method for pumping concrete 12 according to this embodiment using the operation of the concrete pumping pump 10 shown in Figs. 1 and 2. Specifically, Fig. 4 shows the operation in the first pumping step (S10), Fig. 5 shows the operation in the first rotation step (S20), Fig. 6 shows the operation in the second pumping step (S30), Fig. 7 shows the operation in the second rotation step (S40), and Fig. 8 shows the operation in the first pumping step (S10) again. Note that some components such as the control device 60, the drive mechanism 31, the first hydraulic cylinder 43, and the second hydraulic cylinder 53 are omitted in Figs. 4 to 8. Also, the concrete 12 is shown by shading in Figs. 4 to 8.

As shown in Figure 3, the method for pumping concrete 12 according to this embodiment is characterized by repeating a first pumping step (S10), a first rotation step (S20), a second pumping step (S30), and a second rotation step (S40). By sequentially executing and repeating S10 to S40, this pumping method can sequentially discharge the concrete 12 sucked from the hopper 23 into the second pipe 25.

First, the operator starts the concrete pump 10, which is installed, for example, on a pump truck, and operates the control device 60 to start pumping the concrete 12.

As shown in FIG. 4, in the first pumping step (S10), the first plunger 42 is moved backward to suck the concrete 12 from the first opening 21 formed in the fixed base 20 into the first cylinder 41 connected to the first opening 21, and the second plunger 52 is moved forward to discharge the concrete 12 in the second cylinder 51 from the second opening 22 formed in the fixed base 20 to the second piping 25 connected to the second opening 22. The discharge amount of concrete 12 includes the cylinder volume of the second cylinder 51 as well as the volume of the through hole of the rotating plate 30. The second plunger 52 passes beyond the fixed end of the second cylinder 51 and enters the through hole of the rotating plate 30, and stops just before the fixed base 20. The flow of the concrete 12 is indicated by arrows.

As shown in FIG. 5, in the first rotation step (S20), after the first pumping step (S10), the driving mechanism 31 (FIG. 1) is driven to rotate the rotating plate 30 to which the first cylinder 41 and the second cylinder 51 are fixed in the forward direction (clockwise) by 180 degrees relative to the fixed base 20 to connect the first cylinder 41 to the second opening 22 and connect the second cylinder 51 to the first opening 21. At the rotation stop position, the second cylinder 51 communicates with the first pipe 24 and the hopper 23 via the first opening 21, and the first cylinder 41 communicates with the second pipe 25 via the second opening 22. Since the rotating plate 30 slides relative to the fixed base 20, the concrete 12 filled in the through hole formed in the rotating plate 30 hardly leaks out from between the rotating plate 30 and the fixed base 20. Also, the order of the rotation direction may be reversed.

As shown in FIG. 6, in the second pumping step (S30), after the first rotation step (S20), the second plunger 52 is retracted to suck the concrete 12 into the second cylinder 51 through the first opening 21, and the first plunger 42 is advanced to discharge the concrete 12 in the first cylinder 41 through the second opening 22 to the second pipe 25.

As shown in FIG. 7, the second rotation step (S40) involves driving the drive mechanism 31 (FIG. 1) to rotate the rotating plate 30 180 degrees in the opposite direction (counterclockwise) relative to the fixed base 20 after the second pumping step (S30) to connect the first cylinder 41 to the first opening 21 and connect the second cylinder 51 to the second opening 22.

Then, the process returns to the first pumping step (S10) shown in FIG. 8, and then the first rotation step (S20) to the second rotation step (S40) are repeatedly executed. The method for pumping concrete 12 according to this embodiment is repeatedly executed until the operator stops the concrete pumping pump 10, and the concrete 12 continues to be pumped from the hopper 23 to the second pipe 25.

In this way, according to the method for pumping concrete 12 according to this embodiment, the two cylinders can be alternated by rotating to pump the concrete 12 sequentially, realizing a reduction in the installation area of the concrete pump 10 compared to conventional methods.

3. Concrete Pumpability Evaluation Test Apparatus The concrete pumpability evaluation test apparatus 100 according to one embodiment of the present invention will be described with reference to Fig. 9. Fig. 9 is a plan view of the concrete pumpability evaluation test apparatus 100 according to this embodiment, partially shown in cross section. Note that the pumpability evaluation test apparatus 100 has the same basic configuration as the concrete pumping pump 10, and therefore descriptions of parts that overlap with the concrete pumping pump 10 in Figs. 1 and 2 will be omitted.

As shown in FIG. 9, the concrete pumpability evaluation test device 100 includes a concrete pumping pump 10 and a pipe 240 having one end connected to a first opening 21 and the other end connected to a second opening 22.

In the pumpability evaluation test device 100 in FIG. 9, instead of the first pipe 24 and the second pipe 25 of the concrete pumping pump 10 in FIG. 1, a single pipe 240 is connected to the first opening 21 and the second opening 22. In the pumpability evaluation test device 100, an electric motor 310 is attached to the fixed base 20 as a drive mechanism for the rotating plate 30.

For convenience of illustration, the pipe 240 is shown as being formed into an inverted U-shape with a curved section connecting two short straight sections, but this is not limiting and the straight sections may be set longer, or multiple curved sections may be provided. The length and diameter of the pipe 240 can be set appropriately according to the content of the evaluation test. In the illustrated example, the pipe 240 has no openings other than both ends connected to the first opening 21 and the second opening 22, but an openable opening may be provided to fill the inside of the pipe 240 with concrete before the evaluation test.

The electric motor 310 is fixed to the surface of the fixed base 20 on the opposite side to the rotating plate 30. The electric motor 310 has a rotating shaft that passes through the fixed base 20 and extends along the rotation axis 35 and is fixed to the rotating plate 30, and rotates the rotating plate 30 intermittently around the rotation axis 35 in increments of 180 degrees in response to commands from the control device 60.

The pumpability evaluation test device 100 drives the first hydraulic cylinder 43 and the second hydraulic cylinder 53 in response to a command from the control device 60, and retracts the plunger (first plunger 42 in FIG. 9) in the cylinder (first cylinder 41 in FIG. 9) connected to the first opening 21, thereby allowing concrete to be stored from the pipe 240 into the cylinder through the first opening 21. At the same time, the pumpability evaluation test device 100 advances the plunger (second plunger 52 in FIG. 9) in the cylinder (second cylinder 51 in FIG. 9) connected to the second opening 22, thereby discharging the concrete stored in the cylinder to the pipe 240. In addition, when the suction and discharge are completed, the pumpability evaluation test device 100 drives the electric motor 310 in response to a command from the control device 60, and rotates the rotating plate 30 180 degrees relative to the fixed base 20, thereby allowing the first cylinder 41 and the second cylinder 51 to be interchanged. Note that more specific operations of the pumpability evaluation test device 100 will be described later.

The pumpability evaluation test device 100 according to this embodiment can circulate the concrete 12 in the pipe 240 in one direction, so that pumpability can be evaluated using a shorter pipe 240 than in the conventional actual pipe test. The shorter pipe 240 can save space in the test facility, and the facility cost can be reduced. In addition, since only the concrete 12 filled in the pumpability evaluation test device 100 is circulated, the cost of disposing of used concrete can be significantly reduced. Furthermore, the pumpability evaluation test device 100 can flow concrete in one direction in the pipe 240 as in the conventional actual pipe test, so that a pumping state close to that of the actual pipe test can be simulated. In particular, the change in the properties of concrete during pumping is generally considered to be mainly caused by shear deformation (pulsation) of the concrete in the pipe due to the discharge of the concrete through the cylinder of the pump pump, in addition to changes over time. However, the pumpability evaluation test device 100 can simulate unidirectional pulsation in the pipe 240, so that property changes close to those of the actual pipe test can be reproduced.

4. Concrete Pumpability Evaluation Test Method Using Figures 9 to 14, a pumpability evaluation test method for concrete 12 according to one embodiment of the present invention will be described. Figure 10 is a flowchart of the pumpability evaluation test method for concrete 12 according to this embodiment, and Figures 11 to 14 are schematic diagrams explaining the pumpability evaluation test method for concrete 12 according to this embodiment using the operation of the pumpability evaluation test device 100. Specifically, Figure 11 shows the operation of the first pumping step (S12), Figure 12 shows the operation of the first rotation step (S22), Figure 13 shows the operation of the second pumping step (S32), and Figure 14 shows the operation of the second rotation step (S42). In Figures 11 to 14, the concrete 12 is circulated in four types of shading to make the circulating state easier to understand, but it can be changed depending on the length of the pipe 240 and the cylinder volume.

First, the operator fills the circulation path including the piping 240 in the pumpability evaluation test device 100 with concrete 12 that has been prepared in advance, and operates the control device 60 to start the pumpability evaluation test of the concrete 12.

As shown in Fig. 10, the pumpability evaluation test method for concrete 12 is characterized in that a first pumping step (S12), a first rotation step (S22), a second pumping step (S32), and a second rotation step (S42) are repeated until the inside of the pipe 240 is blocked. In the pumpability evaluation test method, concrete 12 is circulated in one direction in the pipe 240 by repeating S12 to S42. The pumpability evaluation test method may further include a first determination step (S14) and a second determination step (S34) for determining whether the inside of the pipe 240 is blocked.

As shown in FIG. 11, the first pumping step (S12) involves moving the second plunger 52 forward to discharge the concrete 12 in the second cylinder 51 connected to the second opening 22 formed in the fixed base 20 into the pipe 240 whose one end is connected to the second opening 22 formed in the fixed base 20, and moving the first plunger 42 backward to suck the concrete 12 from the pipe 240 whose other end is connected to the first opening 21 formed in the fixed base 20 into the first cylinder 41 connected to the first opening 21. Therefore, the same amount of concrete 12 as the concrete 12 discharged from the second cylinder 51 is sucked into the first cylinder 41.

The first judgment step (S14) is executed, for example, after the first pumping step (S12). In the first judgment step (S14), the calculation unit 61 (FIG. 9) judges whether the inside of the pipe 240 is in a blocked state based on the measurement results of, for example, a strain gauge (not shown) installed in the pipe 240 and a pressure gauge of the second hydraulic cylinder 53. The blocked state is a state in which the fluidity of the concrete 12 moving in the pipe 240 is significantly reduced, for example, a state in which the measurement result of a sensor exceeds a predetermined threshold value. If the calculation unit 61 judges that the pipe 240 is in a blocked state, the evaluation test is terminated, and if the calculation unit 61 judges that the pipe 240 is not in a blocked state, the first rotation step (S22) is executed. In this embodiment, the first judgment step (S14) and the second judgment step (S34) described later are provided after each pumping step, but this is not limited to this. If the output value from each sensor exceeds a predetermined threshold value, the pumpability evaluation test may be terminated even during each step (S12, S22, S32, S42).

As shown in FIG. 12, in the first rotation step (S22), after the first pumping step (S12), the electric motor 310 is driven to rotate the rotating plate 30 to which the first cylinder 41 and the second cylinder 51 are fixed relative to the fixed base 20, thereby connecting the first cylinder 41 to the second opening 22 and connecting the second cylinder 51 to the first opening 21. At this time, the first cylinder 41 is filled with the concrete 12 sucked in during the first pumping step (S12), and is in a state in which the concrete 12 can be discharged toward the second opening 22.

As shown in FIG. 13, the second pumping step (S32) involves moving the first plunger 42 forward to discharge the concrete 12 in the first cylinder 41 through the second opening 22 into the piping 240, and moving the second plunger 52 backward to suck the concrete 12 from the piping 240 into the second cylinder 51. In the first pumping step (S12) and the second pumping step (S32), the concrete 12 in the piping 240 is always pumped in only one direction.

In the second determination step (S34), the calculation unit 61 (FIG. 9) determines whether the inside of the pipe 240 is blocked or not based on the measurement results of each sensor, etc. If the calculation unit 61 determines that the inside of the pipe 240 is blocked, the evaluation test ends, and if the calculation unit 61 determines that the inside of the pipe 240 is not blocked, the second rotation step (S42) is executed.

As shown in FIG. 14, in the second rotation step (S42), after the second pumping step (S32), the electric motor 310 is driven to rotate the rotating plate 30 relative to the fixed base 20 to connect the first cylinder 41 to the first opening 21 and connect the second cylinder 51 to the second opening 22. By repeating steps S12 to S42 until the inside of the pipe 240 is blocked, the concrete 12 circulates in the first cylinder 41, the pipe 240, and the second cylinder 51, and a pumpability evaluation test of the concrete 12 using an actual pipe can be simulated. The pumping distance is calculated by multiplying the stroke length of the first plunger 42 and the second plunger 52 by the number of discharges from the first opening 21. The number of discharges may be measured, for example, by the calculation unit 61 based on the number of signals from the sensor 65.

The pumpability evaluation test method according to this embodiment can evaluate pumpability using a pipe 240 that is extremely short compared to conventional actual pipe tests, which allows for space saving in the test equipment and can significantly reduce equipment costs and the cost of disposing of used concrete 12.

The present invention is not limited to the above-described embodiments, and various modifications are possible. For example, the present invention includes configurations that are substantially the same as those described in the embodiments (for example, configurations with the same functions, methods, and results, or configurations with the same purpose and effect). The present invention also includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. The present invention also includes configurations that achieve the same effects as the configurations described in the embodiments, or that can achieve the same purpose. The present invention also includes configurations in which publicly known technology is added to the configurations described in the embodiments.

10...concrete pump, 12...concrete, 20...fixed base, 21...first opening, 22...second opening, 23...hopper, 24...first pipe, 25...second pipe, 30...rotating plate, 31...driving mechanism, 32...rotating hydraulic cylinder, 33...rack, 34...pinion gear, 35...rotation axis, 40...mounting plate, 41...first cylinder, 42...first plunger, 43...first hydraulic cylinder, 51...second cylinder, 52...second plunger, 53...second hydraulic cylinder, 60...control device, 61...calculation unit, 62...storage unit, 65...sensor, 100...pumping performance evaluation test device, 240...piping, 310...electric motor

Claims (2)

a fixed base having a first opening and a second opening;
A rotating plate that is rotatable about a rotation axis relative to the fixed base;
A drive mechanism for rotating the rotary plate;
Two cylinders fixed to the rotating plate at equal distances from the rotation axis;
Two plungers each moving back and forth within the two cylinders;
Equipped with
the two cylinders can be alternately connected to the first opening and the second opening by rotating the rotary plate using the drive mechanism;
By retracting the plunger in the cylinder connected to the first opening, concrete can be poured into the cylinder through the first opening,
a concrete pump capable of discharging concrete contained in the cylinder by advancing the plunger in the cylinder connected to the second opening;
a pipe having one end connected to the first opening and the other end connected to the second opening;
Equipped with
A test device for evaluating the pumpability of concrete, characterized in that the two cylinders are alternately connected to the first opening and the second opening, thereby enabling circulating and moving concrete from the second opening to the first opening . a first pumping step of discharging concrete in a second cylinder connected to a second opening formed in a fixed base into a pipe having one end connected to the second opening, and sucking concrete from the pipe having the other end connected to a first opening formed in the fixed base into a first cylinder connected to the first opening;
a first rotation step of rotating a rotary plate to which the first cylinder and the second cylinder are fixed relative to the fixed base to connect the first cylinder to the second opening and connect the second cylinder to the first opening after the first pressure-feeding step;
a second pumping step of discharging the concrete in the first cylinder through the second opening into the piping and sucking the concrete from the piping into the second cylinder;
a second rotation step of rotating the rotary plate relative to the fixed base after the second pumping step to connect the first cylinder to the first opening and connect the second cylinder to the second opening;
and circulating the concrete from the second opening to the first opening until the inside of the pipe becomes clogged.

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