LOAD TEST DEVICE, LOAD DETECTION UNIT, AND LOAD TEST METHOD

Abstract

To highly accurately measure a load in a horizontal direction of a test body.SOLUTION: A load detection unit 11 has: a mounting table 110 where a test body 3 is mounted; a first bearing 111; a first support plate 112 mounted on the first bearing 111; a second bearing 113 mounted on the first support plate 112; a second support plate 114 mounted on the second bearing 113; a third bearing 115 mounted on the second support plate 114; a third support plate 116 which is arranged on the third bearing 115, and is moved to the second support plate 114 in the same direction as the first support plate 112 by only the same amount; a horizontal movement mechanism 117 for supporting the mounting table 110 so as to be movable to the third support plate 116 in a horizontal direction; a first load cell 118 for measuring a horizontal load applied to the mounting table 110; a second load cell 119 for measuring a horizontal load applied to the first and third support plates 112 and 116; and a third load cell 120 for measuring a horizontal load applied to the second support plate 114.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a load testing device for measuring a horizontal load applied to a test specimen such as a laminated rubber bearing. [Background technology]

[0002] A load testing device is known that measures the horizontal load (horizontal resistance) on a test specimen, such as a laminated rubber bearing, when a vertical load is applied to the upper surface of the test specimen while the lower surface of the test specimen is displaced horizontally.

[0003] For example, the load testing device described in Patent Document 1 comprises a movable base on which a test specimen is placed and which can be moved horizontally by a horizontal actuator, a first pressure member which abuts the top surface of the test specimen, a laminated rubber placed on the first pressure member, a second pressure member which is placed on the laminated rubber and which can be moved vertically by a vertical actuator, and a load cell which measures the horizontal load applied to the first pressure member.

[0004] In the load testing device described in Patent Document 1, the horizontal load applied to the first pressure member measured by the load cell is the sum of the horizontal loads of the test specimen and the laminated rubber, and does not include the frictional force of the means for horizontally moving the movable base (roller bearings, linear guides, etc.). Furthermore, the laminated rubber has high vertical stiffness but low horizontal stiffness, and its horizontal load is proportional to the amount of horizontal displacement. Therefore, if the horizontal movement of the movable base is extremely small, the horizontal load of the laminated rubber included in the load cell measurement can be reduced. Therefore, the load testing device described in Patent Document 1 can measure the horizontal load of the test specimen with high accuracy. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2016-45100 A Summary of the Invention [Problem to be solved by the invention]

[0006] As mentioned above, laminated rubber has high vertical stiffness but low horizontal stiffness, and its horizontal load is proportional to the amount of horizontal displacement. Therefore, in the load testing device described in Patent Document 1, as the horizontal movement of the movable base increases, the horizontal load of the laminated rubber included in the load cell measurement value also increases proportionally. The lower the horizontal stiffness of the laminated rubber, the smaller the load can be, but to do so, it is necessary to increase the number of laminated rubber layers, which results in an increase in the size of the load testing device.

[0007] The present invention has been made in view of the above circumstances, and an object of the present invention is to make it possible to measure the horizontal load applied to a test specimen with higher accuracy without increasing the size of the device. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention uses a load detection unit having a mounting table on which a test specimen such as a laminated rubber bearing is placed and which can be moved horizontally by a horizontal actuator.

[0009] A load detection unit according to a first aspect of the present invention further includes a first bearing, a first support plate placed on the first bearing, a second bearing placed on the first support plate, a second support plate placed on the second bearing and movable horizontally relative to the first support plate, a third bearing placed on the second support plate, a third support plate arranged on the third bearing and connected to the first support plate so as to move in the same direction and by the same amount relative to the second support plate as the first support plate, a horizontal movement mechanism supporting a mounting table so as to be movable horizontally relative to the third support plate, a first load cell measuring a horizontal load applied to the mounting table, a second load cell measuring horizontal loads applied to the first and third support plates, and a third load cell measuring a horizontal load applied to the second support plate. The first to third bearings may be rubber bearings with the same shear spring constant or roller bearings with the same friction coefficient.

[0010] For example, a load testing device according to a first aspect of the present invention includes: A load testing device that measures a horizontal load applied to a test body when a vertical load is applied to an upper surface of the test body and a lower surface of the test body is displaced in the horizontal direction, a load detection unit having a mounting table on which the test object is placed and which is movable in a horizontal direction by a horizontal actuator; a pressure plate that contacts the upper surface of the test piece and is movable in the vertical direction by a vertical actuator; The load detection unit The first bearing and a first support plate placed on the first support; a second bearing placed on the first support plate; a second support plate placed on the second support and horizontally movable relative to the first support plate; a third bearing placed on the second support plate; a third support plate disposed on the third support and connected to the first support plate so as to move in the same direction and by the same amount relative to the second support plate as the first support plate; a horizontal movement mechanism that supports the mounting table so that the mounting table can move horizontally relative to the third support plate; a first load cell for measuring a horizontal load applied to the mounting table; a second load cell that measures a horizontal load applied to the first support plate and the third support plate; The device further includes a third load cell that measures a horizontal load applied to the second support plate.

[0011] A load detection unit according to a second aspect of the present invention further includes a support, a support plate placed on the support, a horizontal movement mechanism that supports the mounting table so that it can move horizontally relative to the support plate, a first load cell that measures the horizontal load applied to the mounting table, and a second load cell that measures the horizontal load applied to the support plate. Note that the support may be a rubber bearing or a roller bearing.

[0012] For example, a load testing device according to a second aspect of the present invention includes: A load testing device that measures a horizontal load applied to a test body when a vertical load is applied to an upper surface of the test body and a lower surface of the test body is displaced in the horizontal direction, a load detection unit having a mounting table on which the test object is placed and which is movable in a horizontal direction by a horizontal actuator; a pressure plate that contacts the upper surface of the test piece and is movable in the vertical direction by a vertical actuator; The load detection unit Support and a support plate placed on the support; a horizontal movement mechanism that supports the mounting table so that the mounting table can move horizontally relative to the support plate; a first load cell for measuring a horizontal load applied to the mounting table; The support plate further includes a second load cell for measuring a horizontal load applied to the support plate. [Effects of the Invention]

[0013] In the first aspect of the present invention, when a vertical load is applied to the pressure plate by the vertical actuator while the mounting table is moved horizontally by the horizontal actuator, the horizontal load applied to the mounting table, measured by the first load cell, is the sum of the horizontal load of the test object and the frictional force of the horizontal movement mechanism, and can be expressed as the sum of the horizontal load of the test object, the horizontal loads applied to the first and third support plates, measured by the second load cell, the horizontal load applied to the second support plate, and the horizontal load on the first support, measured by the third load cell. Therefore, the horizontal load of the test object can be calculated by subtracting the measured values ​​of the second load cell, the third load cell, and the horizontal load on the first support from the measured value of the first load cell.

[0014] Here, the horizontal load applied to the first and third support plates, which is the measurement value of the second load cell, is the value obtained by subtracting the horizontal loads of the first to third supports from the frictional force of the horizontal movement mechanism. Therefore, in the above calculation of the horizontal load of the test specimen, by subtracting the measurement value of the second load cell from the measurement value of the first load cell, which is the sum of the horizontal load of the test specimen and the frictional force of the horizontal movement mechanism, the influence of the frictional force of the horizontal movement mechanism can be removed from the calculated value.

[0015] The horizontal load applied to the second support plate, which is the measurement value of the third load cell, is the sum of the horizontal loads applied to the second and third supports.

[0016] If the first, second, and third bearings are rubber bearings with the same shear spring constant, the horizontal load on these bearings is the product of this shear spring constant and its horizontal displacement. Here, the horizontal load applied to the second support plate, measured by the third load cell, is the sum of the horizontal loads on the second and third bearings. Therefore, the shear spring constant can be expressed by the measurement value of the third load cell and the horizontal displacement of the second and third bearings. Furthermore, the horizontal displacement of the second and third bearings is the value obtained by subtracting the displacement of the third load cell from the displacement of the second load cell, which is the same as the horizontal displacement of the first bearing. The displacement of each of the second and third load cells can then be expressed using their respective measurements and stiffness. Therefore, the horizontal load on the first support can be expressed using the measurement values ​​and stiffness of the second and third load cells, and the horizontal load on the test specimen can be calculated using the measurement values ​​of the first to third load cells without depending on the shear spring constants of the first to third support.

[0017] Furthermore, if the first to third bearings are roller bearings with the same coefficient of friction, the horizontal load on these bearings is the product of this coefficient of friction and the vertical load applied by the vertical actuator. Here, the horizontal load applied to the second support plate, which is the measurement value of the third load cell, is the sum of the horizontal loads applied to the second and third bearings, respectively. Therefore, the coefficient of friction can be expressed as the measurement value of the third load cell and the vertical load applied by the vertical actuator. Therefore, the horizontal load on the test specimen can be calculated using the measurements of the first to third load cells, without relying on the coefficients of friction of the first to third bearings.

[0018] As described above, according to the first aspect of the present invention, the horizontal load applied to the test specimen can be measured with higher accuracy.

[0019] In the second aspect of the present invention, when a vertical load is applied to the pressure plate by the vertical actuator while the mounting table is moved horizontally by the horizontal actuator, the horizontal load applied to the mounting table, which is the measurement value of the first load cell, is the sum of the horizontal load of the test object and the frictional force of the horizontal movement mechanism, and can be expressed as the sum of the horizontal load of the test object, the horizontal load applied to the support plate, and the horizontal load of the bearing, which are measurements of the second load cell. Therefore, the horizontal load of the test object can be calculated by subtracting the measurement value of the second load cell and the horizontal load of the bearing from the measurement value of the first load cell.

[0020] Here, the horizontal load applied to the support plate, which is the measurement value of the second load cell, is the value obtained by subtracting the horizontal load of the support from the frictional force of the horizontal movement mechanism. Therefore, in the above calculation of the horizontal load of the test specimen, by subtracting the measurement value of the second load cell from the measurement value of the first load cell, which is the sum of the horizontal load of the test specimen and the frictional force of the horizontal movement mechanism, the influence of the frictional force of the horizontal movement mechanism can be removed from the calculated value.

[0021] Furthermore, if the bearing is a rubber bearing, the horizontal load of the bearing is the product of its shear spring constant and its horizontal displacement. Here, the horizontal displacement of the bearing is the same as the displacement of the second load cell, so it can be expressed using the measurement value and stiffness of the second load cell. Therefore, the horizontal load of the bearing can be expressed using the shear spring constant of the bearing and the measurement value and stiffness of the second load cell. Therefore, unlike the first aspect of the present invention, in which rubber bearings with the same shear spring constant are used for the first, second, and third bearings, the horizontal load of the test specimen calculated using the measurements of the first and second load cells depends on the shear spring constant of the bearing. However, the shear spring constant of the bearing is extremely small compared to the stiffness of the second load cell. The impact of this can be minimized by determining the shear spring constant of the bearing in advance or periodically. Meanwhile, the load detection unit configuration can be simplified, allowing for a more compact load testing device.

[0022] Furthermore, if the bearing is a roller bearing, the horizontal load applied to this bearing is the product of its friction coefficient and the vertical load from the vertical actuator. Therefore, unlike the first embodiment of the present invention, in which roller bearings with the same friction coefficient are used for the first to third bearings, the horizontal load of the test specimen calculated using the measurements from the first and second load cells depends on the friction coefficient of the bearing. Therefore, to determine the horizontal load of the test specimen with high accuracy, it is necessary to reduce the friction coefficient of the bearing as much as possible. By determining the friction coefficient of the bearing in advance or periodically, its influence can be reduced. Meanwhile, the load detection unit can be simplified, allowing for a more compact load testing device.

[0023] Thus, according to the second aspect of the present invention, the load testing device can be made smaller than the first aspect of the present invention. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 1 is a schematic diagram of a load testing device 1 according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a diagram for explaining the loads applied to the various parts of the load testing device 1. As shown in FIG. [Figure 3] FIG. 3 is a flow diagram for explaining a load testing method using the load testing device 1. As shown in FIG. [Figure 4] FIG. 4 is a schematic diagram of a modified example 1a of the load testing device 1. As shown in FIG. [Figure 5] FIG. 5 is a schematic diagram of a modified example 1b of the load testing device 1. As shown in FIG. [Figure 6] FIG. 6 is a view of a modified example 1b of the load testing apparatus 1 in FIG. 5, viewed from the X direction. [Figure 7] FIG. 7 is a diagram for explaining the load applied to each part in the modified example 1c of the load testing apparatus 1. In FIG. [Figure 8] FIG. 8 is a schematic diagram of a load testing device 2 according to the second embodiment of the present invention. [Figure 9] FIG. 9 is a diagram for explaining the loads applied to the various parts of the load testing device 2. As shown in FIG. [Figure 10] FIG. 10 is a flow diagram for explaining a load testing method using the load testing device 2. As shown in FIG. [Figure 11] FIG. 11 is a diagram for explaining the load applied to each part in the modified example 2a of the load testing device 2. DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0026] [First embodiment] FIG. 1 is a schematic diagram of a load testing device 1 according to this embodiment.

[0027] The load testing device 1 of this embodiment is a device for measuring the horizontal load (horizontal resistance) of a test specimen 3 such as a laminated rubber bearing, and as shown in the figure, is equipped with a fixed base 10 with a U-shaped cross section, a load detection unit 11, a horizontal actuator 13, a vertical movement mechanism 14, a vertical actuator 15, and a pressure plate 16.

[0028] The load detection unit 11 is used to measure the measurements required to calculate the horizontal load on the test specimen 3, and includes a mounting table 110 for placing the test specimen 3, a first rubber bearing 111, a first support plate 112, a second rubber bearing 113, a second support plate 114, a third rubber bearing 115, a third support plate 116, a horizontal movement mechanism 117, a first load cell 118, a second load cell 119, and a third load cell 120.

[0029] The first rubber bearing 111 is placed on the fixed base 10 .

[0030] The first support plate 112 is placed on the first rubber bearing 111 and is movable horizontally relative to the fixed base 10 .

[0031] The second rubber bearing 113 is placed on the first support plate 112 .

[0032] The second support plate 114 is placed on the second rubber bearing 113 and is movable horizontally relative to the first support plate 112 .

[0033] The third rubber bearing 115 is placed on the second support plate 114 .

[0034] The third support plate 116 is disposed on the third rubber bearing 115 and is connected to the first support plate 112 by a connecting portion 1161 so as to move in the same direction and by the same amount as the first support plate 112 relative to the second support plate 114.

[0035] Here, the first rubber bearing 111, the second rubber bearing 113, and the third rubber bearing 115 have the same shear spring constant.

[0036] The horizontal movement mechanism 117 is composed of roller bearings, linear guides, etc. placed on the third support plate 116, and supports the loading table 110 placed on the horizontal movement mechanism 117 so that it can move horizontally relative to the third support plate 116.

[0037] The first load cell 118 is disposed between the side surface 1101 of the mounting table 110 and the horizontal actuator 13, and measures the horizontal load applied to the mounting table 110 (the horizontal load between the mounting table 110 and the fixed base 10).

[0038] The second load cell 119 is arranged between the connecting portion 1161 of the first support plate 112 and the third support plate 116 and the vertical wall surface 101 provided on the fixed base 10, and measures the horizontal load applied to the first support plate 112 and the third support plate 116 (the horizontal load between the first support plate 112 and the third support plate 116 and the fixed base 10).

[0039] The third load cell 120 is arranged between the second support plate 114 and the vertical wall surface 102 provided on the fixed base 10, and measures the horizontal load applied to the second support plate 114 (the horizontal load between the second support plate 114 and the fixed base 10).

[0040] The horizontal actuator 13 is attached to the fixed base 10 and applies pressure to the mounting table 110 in the horizontal direction via a first load cell 118. The mounting table 110, which is pressed in the horizontal direction by the horizontal actuator 13, is moved in the horizontal direction relative to the third support plate 116 by a horizontal movement mechanism 117.

[0041] The vertical movement mechanism 14 is composed of roller bearings, linear guides, etc., arranged on the side surface 103 of the fixed base 10 , and supports the pressure plate 16 so that it can move vertically relative to the fixed base 10 .

[0042] The vertical actuator 15 is attached to the fixed base 10 and applies pressure to the pressure plate 16 in the vertical direction.

[0043] The pressure plate 16 is in contact with the upper surface of the test specimen 3 and applies pressure to the test specimen 3 by moving it in the vertical direction using the vertical movement mechanism 14 and the vertical actuator 15 .

[0044] FIG. 2 is a diagram for explaining the loads applied to the various components of the load testing device 1 according to this embodiment.

[0045] As shown in the figure, when a vertical load N is applied to pressure plate 16 by vertical actuator 15 while horizontal actuator 13 moves mounting table 110 in the horizontal direction, the horizontal load applied to mounting table 110, which is the measurement value F1 of first load cell 118, is the sum of the horizontal load Fh of test piece 3 and the friction force of horizontal movement mechanism 117. If the friction coefficient of horizontal movement mechanism 117 is μ, then measurement value F1 of first load cell 118 can be expressed by equation 1.

[0046]

number

[0047] Furthermore, the measurement value F1 of the first load cell 118 can be expressed as the sum of the horizontal applied load Fh of the test specimen 3, the horizontal applied load applied to the first support plate 112 and the third support plate 116, which is the measurement value F2 of the second load cell 119, the horizontal applied load applied to the second support plate 114, which is the measurement value F3 of the third load cell 120, and the horizontal applied load of the first rubber bearing 111. Therefore, the horizontal applied load Fh of the test specimen 3 can be calculated by subtracting the measurement value F2 of the second load cell 119, the measurement value F3 of the third load cell 120, and the horizontal applied load of the first rubber bearing 111 from the measurement value F1 of the first load cell 118. Here, if the shear spring constant of the first rubber bearing 111, the second rubber bearing 113, and the third rubber bearing 115 is kr and the displacement of the first rubber bearing 111 is dx2, the horizontal load Fh on the test specimen 3 can be expressed by the following equation 2.

[0048]

number

[0049] Here, the horizontal load applied to the first support plate 112 and the third support plate 116, which is the measurement value F2 of the second load cell 119, is the value obtained by subtracting the horizontal loads of the first rubber bearing 111, the second rubber bearing 113, and the third rubber bearing 115 from the friction force μ·N of the horizontal movement mechanism 117. Because the first support plate 112 and the third support plate 116 move by the same amount in the same direction relative to the second support plate 114, the displacement amounts of the second rubber bearing 113 and the third rubber bearing 115 are the same. If the displacement amounts of the second rubber bearing 113 and the third rubber bearing 115 are denoted by dxr, the horizontal load applied to the first support plate 112 and the third support plate 116, which is the measurement value F2 of the second load cell 119, can be expressed by Equation 3.

[0050]

number

[0051] As shown in Equation 3, the measurement value F2 of the second load cell 119 includes the friction force μ·N of the horizontal movement mechanism 117. Therefore, in Equation 2, by subtracting the measurement value F2 of the second load cell 119 from the measurement value F1 (see Equation 1) of the first load cell 118, which is the sum of the horizontal load Fh of the test specimen 3 and the friction force μ·N of the horizontal movement mechanism 117, the influence of the friction force μ·N of the horizontal movement mechanism 117 can be removed from the calculated value of the horizontal load Fh of the test specimen 3.

[0052] Furthermore, the horizontal load applied to the second support plate 114, which is the measurement value F3 of the third load cell 120, is the sum of the horizontal loads applied to the second rubber bearing 113 and the third rubber bearing 115, and can be expressed by the following equation 4:

[0053]

number

[0054] Furthermore, from equation 4, the shear spring constant kr of the first rubber bearing 111, the second rubber bearing 113, and the third rubber bearing 115 can be expressed by equation 5 using the measurement value F3 of the third load cell 120 and the displacement dxr of the second rubber bearing 113 and the third rubber bearing 115.

[0055]

number

[0056] Furthermore, the displacement dxr of the second rubber bearing 113 and the third rubber bearing 115 is the value obtained by subtracting the displacement of the third load cell 120 from the displacement of the second load cell 119, and the displacement of the second load cell 119 is the same as the horizontal displacement dx2 of the first rubber bearing 111. When the displacement of the third load cell 120 is dx3, the displacement dxr of the second rubber bearing 113 and the third rubber bearing 115 can be expressed by equation 6.

[0057]

number

[0058] Furthermore, since the measurement value F2 of the second load cell 119 is the product of the stiffness of the second load cell 119 and the displacement amount dx2, if the stiffness of the second load cell 119 is k2, the displacement amount dx2 of the second load cell 119 can be expressed by equation 7.

[0059]

number

[0060] Similarly, the measurement value F3 of the third load cell 120 is the product of the stiffness of the third load cell 120 and the displacement dx3, so if the stiffness of the third load cell 120 is k3, the displacement dx3 of the third load cell 120 can be expressed by equation 8.

[0061]

number

[0062] From equations 5 to 8, the shear spring constant kr of the first rubber bearing 111, the second rubber bearing 113, and the third rubber bearing 115 can be expressed by equation 9 using the measured values ​​F2, F3 and stiffness k2, k3 of the second load cell 119 and the third load cell 120, respectively.

[0063]

number

[0064] Therefore, the horizontal load Fh of the test specimen 3 can be expressed by the number 10, and the horizontal load Fh of the test specimen 3 can be calculated using the measurement values ​​F1 to F3 of the first to third load cells 118 to 120 without depending on the shear spring constant kr of the first rubber bearing 111, the second rubber bearing 113, and the third rubber bearing 115.

[0065]

number

[0066] FIG. 3 is a flow diagram for explaining a load testing method using the load testing device 1 according to this embodiment.

[0067] First, while a vertical load N is applied to the pressure plate 16 by the vertical actuator 15, the horizontal actuator 13 moves the mounting table 110 in the horizontal direction (S10). As a result, the upper surface of the test piece 3 is pressurized by the vertical load N, while the lower surface of the test piece 3 is displaced in the horizontal direction, generating a horizontal load Fh.

[0068] Next, the measurement values ​​F1 to F3 of the first to third load cells 118 to 120 are acquired (S11). The acquired measurement values ​​F1 to F3 of the first to third load cells 118 to 120 are then transmitted to an information processing device such as a personal computer, and the information processing device substitutes the measurement values ​​F1 to F3 into the above-mentioned equation 10 to calculate the horizontal applied load Fh of the test piece 3 (S12).

[0069] In this embodiment, the horizontal applied load Fh of the test specimen 3 is calculated by substituting the measured values ​​F1 to F3 of the first to third load cells 118 to 120 into the above-mentioned equation (10), and the effect of the friction force μ·N of the horizontal movement mechanism 117 can be eliminated from this calculated value. Furthermore, the horizontal applied load Fh of the test specimen 3 can be calculated without depending on the shear spring constant kr of the first rubber bearing 111, the second rubber bearing 113, and the third rubber bearing 115. Therefore, according to this embodiment, the horizontal applied load Fh of the test specimen 3 can be measured with higher accuracy.

[0070] Furthermore, in this embodiment, the horizontal movement mechanism 117 is disposed between the mounting table 110 and the third support plate 116, which reduces the influence of the first rubber bearing 111, the first support plate 112, the second rubber bearing 113, the second support plate 114, the third rubber bearing 115, and the third support plate 116 when the mounting table 110 is moved horizontally by the horizontal actuator 13. This reduces the inertial force when the mounting table 110 is vibrated at a high frequency, allowing the device to be manufactured more inexpensively.

[0071] In this embodiment, when the horizontal actuator 13 moves the mounting table 110 in the horizontal direction and the specimen 3 is deformed as shown in FIG. 2, if the amount of deformation becomes large, a rotational moment acts on the mounting table 110, causing the mounting table 110 to rotate (tilt) clockwise. Rubber has low tensile rigidity and is easily deformed. Therefore, to counter this, a rotation prevention mechanism for the mounting table 110 may be adopted.

[0072] 4, a modified example 1a of the load testing apparatus 1 employs bolts 17 having horizontal movement mechanisms 170, such as roller bearings or sliding bearings, as anti-rotation mechanisms for the first rubber bearing 111, the second rubber bearing 113, and the third rubber bearing 115. The mounting table 110 is formed with an elongated through-hole 1100 that is larger in diameter than the bolt 17 and allows the bolt 17 to move horizontally relative to the mounting table 110, and the first support plate 112, the second support plate 114, and the third support plate 116 are formed with through-holes 1120, 1140, and 1160, each with a diameter larger than the diameter of the bolt 17. In addition, a screw hole 104 that screws into a threaded portion formed at the tip of the bolt 17 is formed in the upper surface of the fixed base 10 (the mounting surface for the first rubber bearing 111). The bolts 17 are passed through the through holes 1100, 1160, 1140, and 1120 in the mounting table 110, the third support plate 116, the second support plate 114, and the first support plate 112, respectively, and with a horizontal movement mechanism 170 interposed between the screw heads and the upper surface of the mounting table 110 (the surface on which the test piece 3 is placed), the tips of the bolts are screwed into the screw holes 104 of the fixed base 10. This allows the mounting table 110, the first support plate 112, the second support plate 114, and the third support plate 116 to move horizontally relative to the fixed base 10, while restricting their movement in the vertical direction, thereby preventing the mounting table 110 from rotating.

[0073] In addition, in variant example 1b shown in Figures 5 and 6, the anti-rotation mechanism for the first rubber bearing 111, the second rubber bearing 113, and the third rubber bearing 115 includes a thin plate portion 1102 that extends from both side surfaces of the mounting table 110 that are parallel to the movement direction (X direction in Figure 5) by the horizontal actuator 13 on the underside (the surface facing the horizontal movement mechanism 117) of the mounting table 110 in a direction perpendicular to this movement direction, a horizontal movement mechanism 300 such as a roller bearing or a sliding bearing that is arranged on the thin plate portion 1102, and a support portion 105 that is fixed to the fixed base 10, faces the thin plate portion 1102, and supports the thin plate portion 1102 via the horizontal movement mechanism 300. By using the horizontal movement mechanism 300 to support both ends (thin plate portions 1102) of the mounting table 110 that are parallel to the movement direction of the horizontal actuator 13 by the support portion 105 of the fixed base 10, horizontal movement of the mounting table 110, the first support plate 112, the second support plate 114, and the third support plate 116 relative to the fixed base 10 is permitted while vertical movement is restricted, thereby preventing rotation of the mounting table 110.

[0074] In this embodiment, the first to third rubber bearings 111, 113, and 115 having the same spring shear constant are used as the first bearing that supports the first support plate 112 so that it can move horizontally relative to the fixed base 10, the second bearing that supports the second support plate 114 so that it can move horizontally relative to the first support plate 112, and the third bearing that supports the third support plate 116 so that it can move horizontally relative to the second support plate 114. However, the present invention is not limited to this. Roller bearings, sliding bearings, etc. having the same friction coefficient may also be used as the first to third bearings.

[0075] In the modified example 1c of the load testing apparatus 1 shown in Figure 7, instead of the first rubber bearing 111, the second rubber bearing 113, and the third rubber bearing 115 having the same shear spring constant, a first roller bearing 121, a second roller bearing 122, and a third roller bearing 123 having the same friction coefficient are used.

[0076] As shown in the figure, when a vertical load N is applied to pressure plate 16 by vertical actuator 15 while horizontal actuator 13 moves mounting table 110 in the horizontal direction, the horizontal load applied to mounting table 110, which is the measurement value F1 of first load cell 118, is the sum of the horizontal load Fh of test piece 3 and the friction force μ·N of horizontal movement mechanism 117, as shown in Equation 1.

[0077] Furthermore, the measurement value F1 of the first load cell 118 can be expressed as the sum of the horizontal applied load Fh of the test specimen 3, the horizontal applied load applied to the first support plate 112 and the third support plate 116, which is the measurement value F2 of the second load cell 119, the horizontal applied load applied to the second support plate 114, which is the measurement value F3 of the third load cell 110, and the horizontal applied load of the first roller bearing 121. Therefore, the horizontal applied load Fh of the test specimen 3 can be calculated by subtracting the measurement value F2 of the second load cell 119, the measurement value F3 of the third load cell 120, and the horizontal applied load of the first roller bearing 121 from the measurement value F1 of the first load cell 118. Here, when the coefficient of friction of the first roller bearing 121, the second roller bearing 122, and the third roller bearing 123 is μr, the horizontal load Fh applied to the test piece 3 can be expressed by Equation 11.

[0078]

number

[0079] Here, the horizontal load applied to the first support plate 112 and the third support plate 116, which is the measurement value F2 of the second load cell 119, is the value obtained by subtracting the horizontal loads of the first roller bearing 121, the second roller bearing 122, and the third roller bearing 123 from the friction force μ·N of the horizontal movement mechanism 117, as shown in Equation 12.

[0080]

number

[0081] As shown in Equation 12, the measurement value F2 of the second load cell 119 includes the friction force μ·N of the horizontal movement mechanism 117. Therefore, in Equation 11, by subtracting the measurement value F2 of the second load cell 119 from the measurement value F1 (see Equation 1) of the first load cell 118, which is the sum of the horizontal load Fh of the test specimen 3 and the friction force μ·N of the horizontal movement mechanism 117, the influence of the friction force μ·N of the horizontal movement mechanism 117 can be removed from the calculated value of the horizontal load Fh of the test specimen 3.

[0082] Furthermore, the horizontal load on the first roller bearing 121, the second roller bearing 122, and the third roller bearing 123 is the product of their friction coefficient μr and the vertical load N from the vertical actuator 15. Here, the horizontal load applied to the second support plate 114, which is the measurement value F3 of the third load cell 120, is the sum of the horizontal loads on the first roller bearing 121 and the second roller bearing 122, and can be expressed by equation 13.

[0083]

number

[0084] Therefore, the friction coefficient μr of the first roller bearing 121, the second roller bearing 122, and the third roller bearing 123 can be expressed by Equation 14 using the measurement value F3 of the third load cell 120.

[0085]

number

[0086] Therefore, the horizontal load Fh applied to the test specimen 3 can be expressed by Equation 15.

[0087]

number

[0088] Therefore, using the measurement values ​​F1 to F3 of the first to third load cells 118 to 120, the horizontal load Fh of the test specimen 3 can be calculated without depending on the friction coefficient μr of the first roller bearing 121, the second roller bearing 122, and the third roller bearing 123.

[0089] [Second embodiment] FIG. 8 is a schematic diagram of a load testing device 2 according to this embodiment.

[0090] The load testing apparatus 2 of this embodiment, like the load testing apparatus 1 of the first embodiment of the present invention, is an apparatus for measuring the horizontal load (horizontal resistance) of a test specimen 3 such as a laminated rubber bearing, and as shown in the figure, is equipped with a fixed base 20 with a U-shaped cross section, a load detection unit 21, a horizontal actuator 23, a vertical movement mechanism 24, a vertical actuator 25, and a pressure plate 26.

[0091] The load detection unit 21 is used to measure the measurements required to calculate the horizontal load on the test specimen 3, and includes a mounting table 210 for placing the test specimen 3, a rubber bearing 211, a support plate 212, a horizontal movement mechanism 217, a first load cell 218, and a second load cell 219.

[0092] The rubber bearing 211 is placed on the fixed base 20 .

[0093] The support plate 212 is placed on a rubber bearing 211 and is movable horizontally relative to the fixed base 20 .

[0094] The horizontal movement mechanism 217 is composed of roller bearings, linear guides, etc. placed on the support plate 212, and supports the loading table 210 placed on the horizontal movement mechanism 217 so that the loading table 210 can move horizontally relative to the support plate 212.

[0095] The first load cell 218 is disposed between the side surface 2101 of the mounting table 210 and the horizontal actuator 23, and measures the horizontal load applied to the mounting table 210 (the horizontal load between the mounting table 210 and the fixed base 20).

[0096] The second load cell 219 is arranged between the side surface 2120 of the support plate 212 and the vertical wall surface 201 provided on the fixed base 20, and measures the horizontal load applied to the support plate 212 (the horizontal load between the support plate 212 and the fixed base 20).

[0097] The horizontal actuator 23 is attached to the fixed base 20 and applies pressure to the mounting table 210 in the horizontal direction via a first load cell 218. The mounting table 210, which is pressed in the horizontal direction by the horizontal actuator 23, is moved in the horizontal direction relative to the support plate 212 by a horizontal movement mechanism 217.

[0098] The vertical movement mechanism 24 is composed of roller bearings, linear guides, etc., arranged on the side surface 203 of the fixed base 20 , and supports the pressure plate 26 so that it can move vertically relative to the fixed base 20 .

[0099] The vertical actuator 25 is attached to the fixed base 20 and presses the pressure plate 26 in the vertical direction.

[0100] The pressure plate 26 is in contact with the upper surface of the test specimen 3 and applies pressure to the test specimen 3 by moving it in the vertical direction using the vertical movement mechanism 24 and the vertical actuator 25 .

[0101] FIG. 9 is a diagram for explaining the loads applied to the various components of the load testing device 2 according to this embodiment.

[0102] As shown in the figure, when the horizontal actuator 23 moves the mounting table 210 in the horizontal direction while the vertical actuator 25 applies a vertical load N to the pressure plate 26, the horizontal load applied to the mounting table 210, which is the measurement value F1 of the first load cell 218, is the sum of the horizontal load Fh of the test piece 3 and the friction force of the horizontal movement mechanism 25. If the friction coefficient of the horizontal movement mechanism 25 is μ, this can be expressed by the above-mentioned equation 1.

[0103] Furthermore, the measurement value F1 of the first load cell 218 can be expressed as the sum of the horizontal load Fh of the test specimen 3, the horizontal load applied to the support plate 212, which is the measurement value F2 of the second load cell 214, and the horizontal load of the rubber bearing 211. Therefore, the horizontal load Fh of the test specimen 3 can be calculated by subtracting the measurement value F2 of the second load cell 219 and the horizontal load of the rubber bearing 211 from the measurement value F1 of the first load cell 218. Here, if the shear spring constant of the rubber bearing 211 is kr and its displacement is dx2, the horizontal load Fh of the test specimen 3 can be expressed by Equation 16.

[0104]

number

[0105] Here, the horizontal load applied to the support plate 212, which is the measurement value F2 of the second load cell 219, is a value obtained by subtracting the horizontal load of the rubber bearing 211 from the friction force μ·N of the horizontal movement mechanism 217, and can be expressed by Equation 17.

[0106]

number

[0107] As shown in Equation 17, the measurement value F2 of the second load cell 219 includes the friction force μ·N of the horizontal movement mechanism 217. Therefore, in Equation 16, by subtracting the measurement value F2 of the second load cell 219 from the measurement value F1 (see Equation 1) of the first load cell 218, which is the sum of the horizontal load Fh of the test specimen 3 and the friction force μ·N of the horizontal movement mechanism 217, the influence of the friction force μ·N of the horizontal movement mechanism 217 can be removed from the calculated value of the horizontal load Fh of the test specimen 3.

[0108] Furthermore, the displacement amount of second load cell 219 is the same as the displacement amount dx2 of rubber bearing 211. Since the measurement value F2 of second load cell 219 is the product of the rigidity of second load cell 219 and the displacement amount dx2, when the rigidity of second load cell 219 is k2, the displacement amount dx2 of second load cell 219 can be expressed by equation 18.

[0109]

number

[0110] Therefore, the horizontal load Fh applied to the test specimen 3 can be expressed by Equation 19.

[0111]

number

[0112] According to equation 19, the horizontal load Fh on the test specimen 3 depends on the shear spring constant kr of the rubber bearing 211, unlike in the first embodiment of the present invention. However, the shear spring constant kr of the rubber bearing 211 is generally extremely small compared to the stiffness k2 of the second load cell 219. By determining the shear spring constant kr of the rubber bearing 211 in advance or periodically, the influence of this can be reduced. On the other hand, compared to the first embodiment of the present invention, the configuration of the load detection unit 21 can be simplified and the load testing apparatus 2 can be made more compact.

[0113] FIG. 10 is a flow diagram for explaining a load testing method using the load testing device 2 according to this embodiment.

[0114] First, while a vertical load N is applied to the pressure plate 26 by the vertical actuator 25, the horizontal actuator 23 moves the mounting table 210 in the horizontal direction (S20). As a result, the upper surface of the test piece 3 is pressurized by the vertical load N, while the lower surface of the test piece 3 is displaced in the horizontal direction, generating a horizontal load Fh.

[0115] Next, the measurement values ​​F1 and F2 of the first and second load cells 218 and 219 are acquired (S21). The acquired measurement values ​​F1 and F2 of the first and second load cells 218 and 219 are then transmitted to an information processing device such as a personal computer, and the information processing device substitutes the measurement values ​​F1 and F2 into the above-mentioned equation 19 to calculate the horizontal applied load Fh of the test piece 3 (S22).

[0116] In this embodiment, the horizontal load Fh of the test specimen 3 is calculated by substituting the measured values ​​F1 and F2 of the first and second load cells 218 and 219 into Equation 19, thereby eliminating the effect of the friction force μ·N of the horizontal movement mechanism 217 from this calculated value. Unlike the first embodiment of the present invention, the calculated value of the horizontal load Fh of the test specimen 3 depends on the shear spring constant kr of the rubber bearing 211. However, the shear spring constant kr of the rubber bearing 211 is generally much smaller than the stiffness k2 of the second load cell 219. By determining the shear spring constant kr of the rubber bearing 211 in advance or periodically, the effect of this can be reduced. On the other hand, compared to the first embodiment of the present invention, the configuration of the load detection unit 21 can be simplified, thereby enabling the load testing apparatus 2 to be made more compact.

[0117] In this embodiment, rubber bearings 211 are used as bearings that support the support plate 212 so that it can move horizontally relative to the fixed base 20. However, the present invention is not limited to this. Roller bearings, sliding bearings, etc. may also be used as bearings that support the support plate 212 so that it can move horizontally relative to the fixed base 20.

[0118] In a modified example 2 a of the load testing device 2 shown in FIG. 11, a roller bearing 221 is used instead of the rubber bearing 211 .

[0119] As shown in the figure, when a vertical load N is applied to pressure plate 26 by vertical actuator 25 while horizontal actuator 23 moves mounting table 210 in the horizontal direction, the horizontal load applied to mounting table 210, which is the measurement value F1 of first load cell 218, is the sum of the horizontal load Fh of test specimen 3, the horizontal load applied to support plate 221, which is the measurement value F2 of second load cell 24, and the horizontal load of roller bearing 221. Therefore, the horizontal load Fh of test specimen 3 can be calculated by subtracting the measurement value F2 of second load cell 219 and the horizontal load of roller bearing 221 from the measurement value F1 of first load cell 218. Here, if the coefficient of friction of roller bearing 221 is μr, the horizontal load Fh of test specimen 3 can be expressed by equation 20.

[0120]

number

[0121] According to Equation 20, the horizontal applied load Fh of the test specimen 3 depends on the friction coefficient μr of the roller bearing 221, unlike in Modification 1c of the first embodiment of the present invention. Therefore, in order to reduce the influence of the horizontal applied load of the roller bearing 221 on the calculated value of the horizontal applied load Fh of the test specimen 3, it is necessary to reduce the friction coefficient μr of the roller bearing 221. By determining the friction coefficient μr of the roller bearing 221 in advance or periodically, this influence can be reduced. On the other hand, compared to Modification 1c of the first embodiment of the present invention, the configuration of the load detection unit 21 can be simplified and the load testing apparatus 2 can be made more compact.

[0122] The embodiments of the present invention have been described above.

[0123] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the invention.

[0124] For example, in each of the above embodiments, a load testing device that measures the applied load in one horizontal direction of the test specimen 3 has been described as an example. However, the present invention is not limited to this. The present invention can also be applied to a load testing device that measures the applied load in two orthogonal directions to the horizontal direction of the test specimen 3.

[0125] 1 and 4, for example, an XY stage or the like is used as the horizontal movement mechanism 117, which supports the mounting table 110 so that it can move in two orthogonal directions in the horizontal direction relative to the third support plate 116. Then, in each of the cross-sectional views in the two orthogonal directions in the horizontal direction, the fixed base 10 and the mounting table 110 are formed, and two horizontal actuators 13, two vertical movement mechanisms 14, two first load cells 118, two second load cells 119, and two third load cells 120 are provided so that the load testing apparatus 1, 1a has the configuration shown in FIGS.

[0126] In addition, in the load testing apparatus 1c shown in Figure 7, an XY stage or the like is used as the horizontal movement mechanism 117, which supports the loading table 110 so that it can move in two directions perpendicular to the horizontal direction relative to the third support plate 116, and instead of the first roller bearing 121, a sliding bearing or the like is used, which supports the first support plate 112 so that it can move in two directions perpendicular to the horizontal direction relative to the fixed base 10, and instead of the second roller bearing 122, a sliding bearing or the like is used, which supports the second support plate 114 so that it can move in two directions perpendicular to the horizontal direction relative to the first support plate 112, and instead of the third roller bearing 123, a sliding bearing or the like is used, which supports the third support plate 116 so that it can move in two directions perpendicular to the horizontal direction relative to the second support plate 114. Then, in each of the two cross-sectional views in two orthogonal directions in the horizontal direction, a fixed base 10 and a mounting table 110 are formed so as to form the load testing device 1c shown in Figure 7, and two horizontal actuators 13, two vertical movement mechanisms 14, two first load cells 118, two second load cells 119, and two third load cells 120 are provided.

[0127] 8, an XY stage or the like is used as the horizontal movement mechanism 217, which supports the mounting table 210 so that it can move in two orthogonal directions in the horizontal direction relative to the support plate 212. Then, in each of the cross-sectional views in the two orthogonal directions in the horizontal direction, the fixed base 20 and the mounting table 210 are formed so that the load testing device 2 has the configuration shown in FIG. 8, and two horizontal actuators 23, two vertical movement mechanisms 24, two first load cells 218, and two second load cells 219 are provided.

[0128] 11, an XY stage or the like is used as the horizontal movement mechanism 217, which supports the mounting table 210 so that it can move in two orthogonal directions in the horizontal direction relative to the support plate 212, and a sliding bearing or the like is used instead of the roller bearing 221, which supports the support plate 221 so that it can move in two orthogonal directions in the horizontal direction relative to the fixed base 20. Then, in each of the cross-sectional views in the two orthogonal directions in the horizontal direction, the fixed base 20 and the mounting table 210 are formed so that the load testing apparatus 2a shown in FIG. 11 is configured, and two horizontal actuators 23, two vertical movement mechanisms 24, two first load cells 218, and two second load cells 219 are provided. [Explanation of symbols]

[0129] 1, 1a, 1b, 1c, 2, 2a: Load test equipment 3: Test specimen 10, 20: Fixed base 11, 21: Load detection unit 13, 23: Horizontal actuator 14, 24: Vertical movement mechanism 15, 25: Vertical actuator 16, 26: Pressure plate 17: Bolt 17: Horizontal movement mechanism 101, 102, 201: Vertical walls 103: Side of fixed base 10 104: Screw hole 105: Support part of fixed base 110, 210: Mounting table 111: First rubber bearing 112: First support plate 113: Second rubber bearing 114: Second support plate 115: Third rubber bearing 116:Third support plate 117, 217, 170, 300: Horizontal movement mechanism 118, 218: First load cell 119, 219: Second load cell 120: Third load cell 121: First roller bearing 122: Second roller bearing 123: Third roller bearing 203: Side of fixed base 20 211: Rubber bearing 212: Support plate 221: Roller bearing 1160: Connection part 1100, 1120, 1140, 1160: Through holes 1101, 2101: Sides of the mounting tables 110, 210 1102: Thin plate part 1161: Connection part 2120: Side of support plate 212

Claims

1. A load testing device that measures a horizontal load applied to a test body when a vertical load is applied to an upper surface of the test body and a lower surface of the test body is displaced in the horizontal direction, a load detection unit having a mounting table on which the test object is placed and which is movable in a horizontal direction by a horizontal actuator; a pressure plate that contacts the upper surface of the test piece and is movable in the vertical direction by a vertical actuator; The load detection unit The first bearing; a first support plate placed on the first support; a second bearing placed on the first support plate; a second support plate placed on the second support and horizontally movable relative to the first support plate; a third bearing placed on the second support plate; a third support plate disposed on the third support and connected to the first support plate so as to move in the same direction and by the same amount relative to the second support plate as the first support plate; a horizontal movement mechanism that supports the mounting table so that the mounting table can move horizontally relative to the third support plate; a first load cell for measuring a horizontal load applied to the mounting table; a second load cell that measures a horizontal load applied to the first support plate and the third support plate; and a third load cell for measuring a horizontal load applied to the second support plate. A load testing device characterized by:

2. 2. The load testing apparatus according to claim 1, The first bearing, the second bearing, and the third bearing are rubber bearings having the same shear spring constant. A load testing device characterized by:

3. 2. The load testing apparatus according to claim 1, The first bearing, the second bearing, and the third bearing are roller bearings having the same coefficient of friction. A load testing device characterized by:

4. A load testing device that measures a horizontal load applied to a test body when a vertical load is applied to an upper surface of the test body and a lower surface of the test body is displaced in the horizontal direction, a load detection unit having a mounting table on which the test object is placed and which is movable in a horizontal direction by a horizontal actuator; a pressure plate that contacts the upper surface of the test piece and is movable in the vertical direction by a vertical actuator; The load detection unit Support and a support plate placed on the support; a horizontal movement mechanism that supports the mounting table so that the mounting table can move horizontally relative to the support plate; a first load cell for measuring a horizontal load applied to the mounting table; and a second load cell for measuring a horizontal load applied to the support plate. A load testing device characterized by:

5. 5. The load testing apparatus according to claim 4, The bearing is a rubber bearing. A load testing device characterized by:

6. 5. The load testing apparatus according to claim 4, The bearing is a roller bearing A load testing device characterized by:

7. A load detection unit used to measure a horizontal load applied to a test specimen, a mounting table on which the test specimen is placed and which is movable in a horizontal direction; The first bearing; a first support plate placed on the first support; a second bearing placed on the first support plate; a second support plate placed on the second support and horizontally movable relative to the first support plate; a third bearing placed on the second support plate; a third support plate disposed on the third support and connected to the first support plate so as to move in the same direction and by the same amount relative to the second support plate as the first support plate; a horizontal movement mechanism that supports the mounting table so that the mounting table can move horizontally relative to the third support plate; a first load cell for measuring a horizontal load applied to the mounting table; a second load cell that measures a horizontal load applied to the first support plate and the third support plate; a third load cell for measuring a horizontal load applied to the second support plate; A load detection unit characterized by:

8. A load detection unit used to measure a horizontal load applied to a test specimen, a mounting table on which the test specimen is placed and which is movable in a horizontal direction; Support and a support plate placed on the support; a horizontal movement mechanism that supports the mounting table so that the mounting table can move horizontally relative to the support plate; a first load cell for measuring a horizontal load applied to the mounting table; and a second load cell for measuring a horizontal load applied to the support plate. A load detection unit characterized by:

9. A load test method for measuring a horizontal load on a test specimen using a load test device, comprising: The load testing device a load detection unit having a mounting table on which the test object is placed and which is movable in a horizontal direction by a horizontal actuator; a pressure plate that contacts the upper surface of the test piece and is movable in the vertical direction by a vertical actuator; The load detection unit The first bearing; a first support plate placed on the first support; a second bearing placed on the first support plate; a second support plate placed on the second support and horizontally movable relative to the first support plate; a third bearing placed on the second support plate; a third support plate disposed on the third support and connected to the first support plate so as to move in the same direction and by the same amount relative to the second support plate as the first support plate; a horizontal movement mechanism that supports the mounting table so that the mounting table can move horizontally relative to the third support plate; a first load cell for measuring a horizontal load applied to the mounting table; a second load cell that measures a horizontal load applied to the first support plate and the third support plate; a third load cell for measuring a horizontal load applied to the second support plate, a vertical actuator is used to move the pressure plate in a vertical direction to apply a vertical load to the upper surface of the test body, while a horizontal actuator is used to move the mounting table in a horizontal direction to displace the lower surface of the test body in a horizontal direction, thereby obtaining measurement values ​​of the first load cell, the second load cell, and the third load cell; Calculating the horizontal load of the test specimen using the acquired measured values ​​of the first load cell, the second load cell, and the third load cell. A load testing method comprising:

10. 10. The load testing method according to claim 9, the first bearing, the second bearing, and the third bearing are rubber bearings having the same shear spring constant; The measurement value of the first load cell is F1, the measurement value of the second load cell is F2, the measurement value of the third load cell is F3, the stiffness of the second load cell is k2, and the stiffness of the third load cell is k3, and the applied load Fh in the horizontal direction of the test body is [0000] Calculate by A load testing method comprising:

11. 10. The load testing method according to claim 9, the first bearing, the second bearing, and the third bearing are roller bearings having the same coefficient of friction; The measurement value of the first load cell is F1, the measurement value of the second load cell is F2, and the measurement value of the third load cell is F3, and the horizontal load Fh of the test specimen is calculated as follows: [Equation 22] Calculate by A load testing method comprising:

12. A load test method for measuring a horizontal load on a test specimen using a load test device, comprising: The load testing device a load detection unit having a mounting table on which the test object is placed and which is movable in a horizontal direction by a horizontal actuator; a pressure plate that contacts the upper surface of the test piece and is movable in the vertical direction by a vertical actuator; The load detection unit Support and a support plate placed on the support; a horizontal movement mechanism that supports the mounting table so that the mounting table can move horizontally relative to the support plate; a first load cell for measuring a horizontal load applied to the mounting table; a second load cell for measuring a horizontal load applied to the support plate; a vertical actuator is used to move the pressure plate in a vertical direction, thereby applying a vertical load to the upper surface of the test body, and a horizontal actuator is used to move the mounting table in a horizontal direction, thereby displacing the lower surface of the test body in a horizontal direction, thereby obtaining measurement values ​​of the first load cell and the second load cell; The horizontal load applied to the test specimen is calculated using the acquired measured values ​​of the first load cell and the second load cell. A load testing method comprising:

13. The load testing method according to claim 12, The bearing is a rubber bearing, The horizontal load Fh of the test specimen is expressed as follows: F1 is the measurement value of the first load cell, F2 is the measurement value of the second load cell, k2 is the rigidity of the second load cell, and kr is the shear spring constant of the support. [Equation 23] Calculate by A load testing method comprising:

14. The load testing method according to claim 12, the bearing is a roller bearing; The measurement value of the first load cell is F1, the measurement value of the second load cell is F2, the friction coefficient of the bearing is μr, and the vertical load applied to the pressure plate by the vertical actuator is N, then the horizontal load Fh of the test specimen is [0000] Calculate by A load testing method comprising:

Images