CN207019989U - A kind of general planar material tension, strain and deflection test device - Google Patents

Abstract

A general planar material tension, strain and deflection testing device, including a pressure loading system, a sample cap, a prestressed loading system, a testing and data acquisition system; the pressure loading system consists of a reaction column, a beam, a base, a servo The feeding device A and the loading head are composed; the prestressed loading system includes a servo feeding device B, a tension sensor and a loading plate; the testing system includes a pressure sensor, a displacement sensor and a laser displacement meter; the data acquisition system includes a data collector and computer. The prepared sample is placed on the sample platform, the prestress loading system and the pressure loading system respectively apply prestress and pressure to the planar material sample, and read the test data of each sensor through the test and data acquisition system. Calculate the pressure, displacement and deflection of the planar material sample based on the data. The utility model can meet the test and test of planar materials with different materials and different constraint conditions.

Description

A universal planar material tension, strain and deflection testing device

technical field

The invention relates to a general planar material tension, strain and deflection test device, which belongs to the technical field of geotechnical engineering.

Background technique

In foundation pit support technology and slope protection system, soil nail wall support technology and anchor shotcrete support technology are one of the commonly used support technologies. Whether it is soil nail wall support technology or anchor shotcrete support technology, an important part of it is the support surface. The so-called supporting surface layer is a rigid or flexible protective surface set in foundation pit and slope protection to prevent local damage to the slope surface. At present, in the soil nail wall support system and anchor shotcrete support system, the surface layer is mostly concrete sprayed surface materials, steel wire mesh, and geosynthetic surface materials, such as geogrids and geotextiles.

The surface layer protects the slope and transmits the earth pressure by limiting the lateral displacement of the foundation pit or slope and transferring the lateral earth pressure of the slope to the soil nail or anchor. In addition, the surface layer plays an important role in preventing slope erosion and slope greening. Therefore, the stiffness and strength of the surface layer play an important role in the stability of the foundation pit and slope support system. Once the surface layer is damaged, the stability of the foundation pit and slope will be greatly threatened. Therefore, when designing the support scheme, the test of the stiffness and strength of the surface layer is an important index.

At present, most of the tests on the surface layer are for the surface material of shotcrete. The test is to test the uniaxial compressive strength of the concrete test block to represent the surface layer strength, and use the deflection of the test block to be hinged with the circular plate type test block. Represents the surface deflection. For the test of geosynthetics planar material, the simple uniaxial bursting strength is also used to represent the strength of geosynthetics planar material. Although the test data of the above method is representative to a certain extent, it uses two sets of equipment and two sets of standards, so it cannot be compared and analyzed. Generally speaking, the support surface on site is mostly connected with anchor rods or soil nails to form a semi-fixed constraint, that is, the surface layer is firmly pressed on the slope by the head of the anchor rod or soil nail. The above method sets the planar material and the test column in the form of hinge constraints, which obviously cannot truly reflect the actual situation on site.

Contents of the invention

The present invention provides a universal planar material tension, strain and deflection testing device. By replacing the sample bearing platform, the test of planar materials of different materials can be realized and test curves can be generated, and the test results of planar materials of different materials can be analyzed. Comparative analysis is convenient for engineering and technical personnel to compare and select materials.

The technical scheme that the present invention takes is:

A general planar material tension, strain and deflection testing device, including a pressure loading system, a sample cap, a prestressed loading system, a testing and data acquisition system; the pressure loading system consists of a reaction column, a beam, a base, a servo The feeding device A is composed of a loading head, the reaction force column is fixedly connected to the base, the beam is fixed on the two reaction force columns, and the servo feeding device A is fixed in the middle of the beam; the pressure One end of the sensor is fixedly connected to the loading head, and the other end is fixedly connected to the servo feeding device A; the sample platform is fixed inside the pressure loading system; the prestress loading system includes a servo feeding device B , a tension sensor, a loading plate and a support ring platform, the servo feeding device B is fixed in the base, one end of the tension sensor is connected to the servo feeding device B, and the other end is connected to the loading plate, and the support ring The platform is placed above the base; the test system includes a pressure sensor, a displacement sensor and a laser displacement meter; the data acquisition system includes a data collector and a computer. Place the prepared sample on the sample platform, respectively apply prestress and pressure to the planar material sample through the prestress loading system and the pressure loading system, and read the pressure sensor through the test and data acquisition system , displacement sensor and laser displacement meter data to calculate the pressure, displacement and deflection of the planar material sample. For planar materials of different materials, the above test can be realized by replacing the sample platform.

Further, the loading head is cylindrical, the head is spherical, and a displacement measuring rod is arranged on the side.

Further, the loading head is fixedly connected with the pressure sensor.

Further, the base is composed of upper and lower steel plates, the upper steel plate is square, a displacement measurement hole is set in the middle, which runs through the steel plate, and 6 through holes are arranged around the regular hexagonal corners.

Further, the sample cap is divided into two types according to the different planar materials and connection methods: for the hinged constraint mode of shotcrete planar material, the sample cap is cylindrical, the top surface is spherical, It is called a hinged sample cap; for the fixed restraint mode of geosynthetics and steel mesh surface materials, the sample cap is composed of a support column and a sample fixture, and the sample fixture is fixed on the support column by bolts , called the fixed specimen platform.

Further, the hinged sample platform connects the support column to the base by inserting the support column into the regular hexagonal through holes of the upper steel plate of the base.

Further, the fixed sample platform is fixedly connected to the loading plate of the prestressing loading system by passing the support column through the regular hexagonal through holes of the upper steel plate of the base.

Further, the sample fixture is composed of two circular steel plates, one side of the steel plate has a sawtooth pattern, and the two circular steel plates clamp the sample through flanges, bolts and nuts.

Further, the prestress applying system includes a servo feeding device B, a tension sensor, a loading plate and a supporting ring platform.

Further, the servo feeding device B is fixed in the base, one end of the tension sensor is fixedly connected to the servo feeding device B, and the other end is fixedly connected to the center of the loading plate, and the loading plate is made of high-strength metal plate.

Further, the testing system includes a pressure sensor, a displacement sensor and a laser displacement gauge.

Further, the pressure sensor is arranged between the servo feeding device A and the loading head, one end is fixedly connected to the servo feeding device A, and the other end is fixedly connected to the loading head.

Further, the displacement sensor is arranged on the displacement meter bracket to test the displacement of the loading head; the laser displacement meter is arranged in the middle of the base, and the laser passes through the displacement measurement hole of the upper steel plate inside the base to measure the sample center displacement.

Further, the tension sensor, pressure sensor, and displacement sensor are all connected to the data collector system through communication cables to realize data collection.

The benefit of a kind of universal planar material tension, strain and deflection testing device and test method of the present invention is:

(1) The present invention can meet the experimental tests of planar materials with different materials and different constraints;

(2) The sample bearing platform in the present invention can be replaced at will according to different materials and constraints, and the operation is simple and convenient;

(3) The present invention can effectively carry out tests on planar materials of different materials and different constraint conditions in a unified manner, which is convenient for data comparison and scheme comparison and selection;

(4) The present invention provides a device for applying prestress to planar materials, which better solves the problem of tensioning and applying prestress to planar material samples;

(5) The present invention adopts an automatic data acquisition device in the whole process, which reduces human interference and has good data reliability;

(6) The present invention is simple in structure, easy to operate, easy to use, and low in manufacturing cost, and is suitable for popularization and application.

Description of drawings

Fig. 1 Schematic diagram of a general planar material tension, strain and deflection test device

Fig. 2 Schematic diagram of the fixed constraint mode structure of a universal planar material tension, strain and deflection test device

Fig. 3 Structural schematic diagram of hinged restraint mode of a universal planar material tension, strain and deflection test device

Figure 4. Schematic diagram of the top view of the upper steel plate of the base

Figure 5 Schematic diagram of the support column for the fixed sample cap

Figure 6 Schematic diagram of the top view of the loading plate

Figure 7 Schematic diagram of cross-section and top view of support ring platform

Figure 8 Front view and top view of specimen fixture

In the figure: 1—base, 2—lower steel plate, 3—upper steel plate, 4—reaction column, 5—beam, 6—loading head, 7—servo feeding device A, 8—pressure sensor, 9—surface material Fixture, 10—supporting ring platform, 11—servo feeding device B, 12—tension sensor, 13—loading plate, 14—fixed sample platform, 15—laser displacement meter, 16—displacement measurement hole, 17—through hole , 18-hinged sample cap, 19-planar material sample, 20-displacement sensor, 21-displacement gauge bracket, 22-support ring table fixing hole, 23-data collector, 24-computer, 25-screw, 26 - screw holes.

detailed description

As shown in Figure 1, a kind of universal planar material tension, strain and deflection testing device, comprise pressure loading system, sample cap, prestress loading system, test and data acquisition system; Described pressure loading system consists of base 1, The reaction force column 4, the crossbeam 5, the loading head 6 and the servo feeding device A7 are composed of the reaction force column 4 and the base 1, and the crossbeam 5 is erected on the two reaction force columns 4, and utilize Bolts are fixed, the servo feeding device A 7 is fixed in the middle of the beam 5, one end of the pressure sensor 8 is fixedly connected to the servo feeding device A 7, and the other end is fixedly connected to the loading head 6 to measure The pressure of the loading head 6; the sample platform is divided into two types: fixed sample platform 14 and hinged sample platform 18; the prestressed loading system includes servo feeding device B 11, tension sensor 12 and Loading plate 13, one end of the tension sensor 12 is fixedly connected to the servo feeding device B 11, and one end is fixedly connected to the center of the loading plate 13; the testing and acquisition system includes a laser displacement meter 15, a displacement sensor 20, a pressure sensor 8, a data Collector 23 and computer 24; Described displacement transducer 20 is fixed on described displacement meter support 21, the displacement of testing loading head; Described laser displacement meter 15 is placed on described loading plate 13 center, makes described laser displacement meter 15 The laser emitting end of the laser is aligned with the displacement measurement hole 16 on the upper steel plate 3, so that the laser can measure the displacement of the center of the planar material sample through the displacement measurement hole 16, and prevent the planar material sample from falling and smashing the laser Displacement gauge16. The pressure sensor 8 , tension sensor 12 , laser displacement gauge 15 and displacement sensor 20 are connected to a data collector 23 through data lines, and the collected data are transmitted to a computer 24 .

First, select the appropriate sample cap according to the material and restraint mode of the test sample, for example, select the hinged specimen cap 18 for the hinged constraint mode of shotcrete planar material; Mode selection fixed sample holder 14 .

Insert the selected sample cap, such as: the hinged sample cap 18 into the through hole 17 of the upper steel plate 3, and be fixedly connected with the upper steel plate 3 of the base; the fixed sample cap 14 passes through the upper steel plate 3 The through-hole 17 is fixedly connected with the screw hole 26 on the loading plate 13 through the screw 25, and the support ring platform 10 is accurately placed on the upper steel plate 3, and the support ring platform 22 is passed through the support ring platform fixing hole 22 on the upper steel plate 3 by the screw. The ring platform 10 is fixed with the upper steel plate 3 .

Place the prepared planar material sample 19 on the sample platform: for the hinged constraint mode of the sprayed concrete planar material, it is necessary to align the center of the sprayed concrete planar material sample 19 with the displacement measurement hole 16 on the upper steel plate 3 center alignment; for the fixed constraint mode of geosynthetics planar material and steel mesh planar material, it is necessary to fix the planar material sample 19 on the planar material fixture 9, and connect the planar material fixture 9 with the fixed sample Platform 14 is fixedly connected.

Turn on the test system and preheat for 15 minutes. For the test of the hinged constraint mode of the sprayed concrete planar material, first make the loading head 6 just touch the planar material sample, pause for a while, and place the displacement sensor 20, the tension sensor 12 and the laser displacement sensor Count 15 to zero.

Continue to open the servo feeding device A 7, officially start the test, and test the surface material sample. During the test, the pressure sensor 8, the displacement sensor 20 and the laser displacement meter 15 transmit the data to the data collector 23 in real time and transmit Give the computer 24 to obtain the load, displacement and deflection data during the test.

Or, before starting the test, for the test of the fixed restraint mode of the geosynthetic surface material and the steel wire mesh surface material, it is necessary to apply prestress to the surface material sample, and the loading plate can be pulled down by turning on the servo feeding device B 11 13 Move the fixed sample platform 14 downward, make the planar material sample 19 contact with the support ring platform 10, and tighten it, read the value on the tension sensor 12, and record it.

Turn on the servo feeding device A 7 to stop the loading head 6 just after contacting the planar material sample, clear the data of the pressure sensor 8, displacement sensor 20 and laser displacement meter 15, and continue to turn on the servo feeding device A 7 to continue the test , record the data of the pressure sensor 8, the displacement sensor 20 and the laser displacement meter 15 through the data collector 23 and the computer 24, and obtain the load, displacement and deflection data during the test.

After the test is completed, the servo feeding device A 7 is retracted, and the tested planar material sample is removed from the sample platform to prepare for the next group of tests.

Claims (6)

1. A general planar material tension, strain and deflection testing device, comprising a pressure loading system, a hinged sample cap, a fixed sample cap, a prestressed loading system, a test and a data acquisition system; the pressure loading system consists of The reaction force column, beam, base, servo feeding device A and loading head are composed, the reaction force column is fixedly connected with the base, the beam is fixed on the two reaction force columns, and the servo feeding device A is fixed In the middle of the beam; one end of the pressure sensor is fixedly connected to the loading head, and the other end is fixedly connected to the servo feeding device A; the sample platform is fixed inside the pressure loading system; The stress loading system includes a servo feeding device B, a tension sensor, a loading plate and a support ring platform, the servo feeding device B is fixed in the base, one end of the tension sensor is connected to the servo feeding device B, and one end Connected with the loading plate, the support ring platform is placed above the base; the test system includes a pressure sensor, a displacement sensor and a laser displacement meter; the data acquisition system includes a data collector and a computer; the prepared sample Placed on the sample platform, apply prestress and pressure to the planar material sample through the prestress loading system and pressure loading system, and read the pressure sensor, displacement sensor and laser displacement through the test and data acquisition system Calculate the pressure, displacement and deflection of the planar material sample based on the data of the meter. 2. A kind of universal planar material tension, strain and deflection testing device according to claim 1, characterized in that: the base is composed of upper and lower layers of steel plates, the upper layer of steel plates is square, and a The displacement measurement hole runs through the steel plate, and 6 through holes are arranged in regular hexagonal corners around it. 3. A kind of universal planar material tension, strain and deflection testing device according to claim 1, characterized in that: said sample caps are divided into two types according to planar materials and connection methods: for spraying For the hinged constraint mode of concrete planar materials, the sample cap is cylindrical and the top surface is spherical, which is called hinged sample cap; for the fixed constraint mode of geosynthetics and steel mesh surface materials, the test The sample cap is composed of a support column and a sample fixture, and the sample fixture is fixed on the support column by bolts, which is called a fixed sample cap. 4. A kind of universal planar material tension, strain and deflection testing device according to claim 1, characterized in that: the hinged sample cap is inserted into the regular hexagonal shape of the upper steel plate of the base by the support column. Connect the support column with the base in the arranged through hole; the fixed sample cap, pass the support column through the regular hexagonal through hole of the upper steel plate of the base and the loading plate of the prestressed loading system Fixed connection. 5. A kind of general planar material tension, strain and deflection testing device according to claim 1, is characterized in that: described prestress applying system comprises servo feeding device B, tension sensor, loading plate and supporting ring platform, The servo feeding device B is fixed in the base, one end of the tension sensor is fixedly connected to the servo feeding device B, and the other end is fixedly connected to the center of the loading plate, and the loading plate is a high-strength metal plate. 6. A kind of universal planar material tension, strain and deflection testing device according to claim 1, characterized in that: the displacement sensor is arranged on the displacement gauge support to test the displacement of the loading head; the laser displacement gauge It is arranged in the middle of the base, and the displacement of the center of the sample is measured by laser passing through the displacement measurement hole of the upper steel plate inside the base.