CN201285357Y - Concrete plane complicated applied force test device - Google Patents

Abstract

The utility model relates to a concrete plane complex force test device, which relates to a concrete force test device. The purpose of the utility model is to solve the problem that when the existing multi-axis test loading equipment is used for the concrete loading test, the lateral deformation of the concrete is limited to cause friction, which causes a large discrepancy between the test result and the actual situation. The second vertical loader of the utility model is fixed on the ground at the center position in the reaction force frame, the first vertical loader is fixed at the lower side of the center position of the crossbeam of the reaction force frame, the first horizontal loader and the second horizontal loader They are respectively fixed on the inner sides of the first steel plate and the second steel plate. The utility model can complete the concrete plane complex force test, that is, the plane stress test of two-way compression, two-way tension, one-way compression and one-way tension, shear compression and shear tension. The two mutually perpendicular loading directions are controlled by the hydraulic servo through the control system, which can automatically adjust the loading speed and the different loading combinations in both directions. It can be used for load-controlled loading tests and deformation-controlled loading tests.

Description

Concrete Plane Complicated Force Test Device

technical field

The utility model relates to a concrete stress test device.

Background technique

Practical concrete structures such as: shear and compression zones of reinforced concrete beams, joint zones of roof trusses and frame beams and columns, anchorage zones of post-tensioned steel bars, pipe columns, corbels, deep beams, wall panels and thin walls, etc. Components, as well as dams, high-pressure vessels of nuclear reactors, etc. are in a two-way and three-way complex force state. However, the concrete strength given by the general reinforced concrete structure design code is the concrete strength under multi-series unidirectional stress state, and the concrete strength, deformation and elastic modulus under complex stress state are all the same as those under unidirectional stress state. Different, the damage mechanism is not the same. Therefore, it is particularly important to develop concrete multiaxial loading equipment under complex stress conditions.

Since A.Foppl in Germany used a relatively simple cross-loading frame to test the strength of two-axis mortar in 1900, the complex force test of concrete has attracted the attention of scholars. Especially after the 1960s, scholars from various countries have successively developed various multiaxial test loading equipment, but since concrete is an inelastic material, its elastic modulus and Poisson's ratio both change during the test, so the The friction between the slab and the concrete specimen is caused by the restriction of the concrete lateral deformation. This friction complicates the stress on the end of the concrete specimen, resulting in a large discrepancy between the test results and the actual situation.

Utility model content

The purpose of this utility model is to solve the existing multiaxial test loading equipment when doing concrete loading test, because concrete is a kind of non-elastic material, its modulus of elasticity and Poisson's ratio all change in the test, so the loading plate and concrete The friction between the specimens is caused by the restriction of the lateral deformation of the concrete. This friction complicates the stress on the ends of the concrete specimens, resulting in a large discrepancy between the test results and the actual situation. To provide a concrete plane Complex force test device. The utility model consists of a first fixed pulley, a second fixed pulley, a steel wire rope, a counterweight, four screws, a first horizontal loader, a first steel plate, a first vertical loader, a reaction force frame, and a second horizontal loader. , the second vertical loader, four pressure plates and the second steel plate, the lower ends of both sides of the reaction frame are fixed on the ground, the second vertical loader is fixed on the ground at the center of the reaction frame, the first A vertical loader is fixed on the lower side of the center position of the crossbeam of the reaction frame, the free ends of the first vertical loader and the second vertical loader are arranged opposite to each other and have the same axis, and the first steel plate and the second steel plate are arranged parallel to each other , there are four screws between the first steel plate and the second steel plate to form a rectangular frame. On the inner side of the second steel plate, the free ends of the first horizontal loader and the second horizontal loader are arranged opposite and have the same axis, the first fixed pulley is arranged on the upper part of the reaction force frame, and the second fixed pulley is arranged on the upper part of the reaction force frame The outer side of the wire rope, one end of the wire rope is connected with the screw on the upper side of the first steel plate and the second steel plate, the other end of the wire rope is connected with the counterweight through the first fixed pulley and the second fixed pulley, and the free end of the first horizontal loader , the free end of the second horizontal loader, the free end of the first vertical loader and the free end of the second horizontal loader are all provided with a pressure bearing plate.

The utility model has the following positive effects: 1. It can complete the concrete plane complex force test, that is, plane stress tests such as two-way compression, two-way tension, one-way compression and one-way tension, shear compression and shear tension. 2. The two mutually perpendicular loading directions are controlled by the hydraulic servo through the control system, which can automatically adjust the loading speed and different loading combinations in both directions. 3. It can be used for load control loading test and deformation control loading test. 4. It can conduct deformation and strength tests such as plane stress of various specimen sizes. 5. A pressure bearing plate is installed in each loading direction, which can eliminate the uneven internal force of the test piece caused by the slight non-parallel between the pressure surfaces of the test piece. 6. There is no need for anti-friction measures, it is convenient to install and disassemble the test piece, and the test efficiency is improved. 7. The data collection is all automatically completed by the computer, and the test accuracy and efficiency are high.

Description of drawings

Fig. 1 is a schematic view of the overall structure of the present utility model, Fig. 2 is a sectional view of A-A of Fig. 1, Fig. 3 is a schematic structural view of a plane two-way stress test piece, Fig. 4 is a schematic view of a plane two-way shear compression test piece, and Fig. 5 is a sample formwork Structural schematic diagram, FIG. 6 is a structural schematic diagram of the pressure bearing plate 13 . Reference numeral 21 in the figure is a reinforcing bar.

Detailed ways

Specific embodiment one: (referring to Fig. 1 and Fig. 2) this embodiment consists of the first fixed pulley 1, the second fixed pulley 2, the steel wire rope 3, the counterweight 4, four screw rods 6, the first horizontal loader 7, the second A steel plate 8, a first vertical loader 9, a reaction force frame 10, a second horizontal loader 11, a second vertical loader 12, four pressure bearing plates 13 and a second steel plate 15, the reaction force frame 10 The lower ends of both sides are fixed on the ground 14, the second vertical loader 12 is fixed on the ground 14 at the center position in the reaction frame 10, and the first vertical loader 9 is fixed at the lower side of the center position of the crossbeam of the reaction frame 10, The free ends of the first vertical loader 9 and the second vertical loader 12 are arranged opposite up and down and have the same axis, the first steel plate 8 and the second steel plate 15 are arranged in parallel to each other, and the first steel plate 8 and the second steel plate 15 are arranged between the first steel plate 8 and the second steel plate 15. There are four screw rods 6 to form a rectangular frame, and this frame is arranged at the center of the inside of the reaction force frame 10, and the first horizontal loader 7 and the second horizontal loader 11 are respectively fixed in the first steel plate 8 and the second steel plate 15. On the side, the free ends of the first horizontal loader 7 and the second horizontal loader 11 are arranged opposite and have the same axis, the first fixed pulley 1 is arranged on the upper part of the reaction force frame 10, and the second fixed pulley 2 is arranged on the reaction force frame 10 On the outer side of the upper part, one end of the wire rope 3 is connected to the screw 6 on the upper side of the first steel plate 8 and the second steel plate 15, and the other end of the wire rope 3 is connected to the counterweight 4 through the first fixed pulley 1 and the second fixed pulley 2 , the free end of the first horizontal loader 7, the free end of the second horizontal loader 11, the free end of the first vertical loader 9 and the free end of the second horizontal loader 11 are all provided with a pressure bearing plate 13 .

Embodiment 2: (see FIG. 1 ) The outer side of the first fixed pulley 1 in this embodiment, that is, the downward trajectory of the wire rope 3 is the same as the axes of the first vertical loader 9 and the second vertical loader 12 . Others are the same as in the first embodiment.

Specific embodiment three: (see Fig. 6) the pressure bearing plate 13 of this embodiment is made up of base plate 17, backing plate 18 and sleeve 19, and one side of base plate 17 is provided with convex spherical cap 16, and backing plate 18 is provided with There is a concave surface 20 matched with the convex spherical cap 16 , the base plate 17 is arranged corresponding to the backing plate 18 , and the backing plate 18 is connected with the sleeve 19 . Concrete specimens are casted with steel molds, but sometimes the four loading surfaces of concrete specimens cannot be absolutely guaranteed to be perpendicular to each other, and it is impossible to ensure the absolute translation of the bearing plate during loading, so the pressure bearing plate of the concrete compression test is designed It is a spherical hinge support to accommodate rotation in two vertical directions. A convex spherical cap 16 is provided on the base plate 17 opposite to the test piece 5. The section radius of the convex spherical cap 16 is 70-80 mm, and the spherical curvature radius of the convex spherical cap 16 is 190-210 mm. The backing plate 18 of the concave surface of the spherical cap is fixed on the free end of the first horizontal loader 7, the second horizontal loader 11, the first vertical loader 9 or the second horizontal loader 11 with a sleeve 19, when loading The spherical center of the spherical crown can be coincided with the center of the test piece, and can be rotated slightly to adapt to the necessary deflection. Others are the same as in the first embodiment.

The operation process of using the device described in the above embodiment: 1. For the pressure test piece 5, firstly, three layers of plastic films are applied, and molybdenum sulfide paste is applied between each layer. For tensile specimen 5, construction glue should be used to bond the loading block and the surface of specimen 5. Install the processed test piece 5 on the loading head, and adjust the position of the test piece through the adjusting screw. 2. Start the loader, apply the initial pressure, generally 2 to 5KN, and check whether the operation of each part is normal and whether the position of the test piece 5 is correct. 3. After removing the initial pressure, start the computer, adjust the displacement gauge to zero, and record the initial value. 4. Enter the normal loading state; after each level of loading, the computer automatically records the load and strain values. 5. When it is found that the load value displayed on the load display has a downward trend, the data acquisition system is controlled by the computer to continuously collect the state immediately, so as to collect the descending section of the stress-strain curve until the load drops to zero. 6. After the computer collects the data, draw the corresponding load-displacement curve and stress-strain diagram. The mass of the counterweight 4 is equal to the mass of the first horizontal loader 7 , the second horizontal loader 11 , the screw 6 , the first steel plate 8 and the second steel plate 15 in the horizontal direction. When loading, the loader in the horizontal direction can move up and down freely, so that the test piece is evenly stressed. Since the loaders in each direction are independent and orthogonal to each other, the forced stress generated in the specimen by mechanical confinement is avoided.

(See Figures 3 to 5) The length × width of the template for making the test piece is 300mm × 300mm, and the thickness can be determined according to specific tests. The formwork can be used to make specimens for five tests of two-way compression, two-way tension, one-way compression and one-way tension, shear compression and shear tension. Just fill it.

Claims (5)

1, a kind of concrete plane complicated applied force test device, it is by first fixed pulley (1), second fixed pulley (2), wire rope (3), mass (4), four screw rods (6), the first horizontal loader (7), first steel plate (8), the first vertical loader (9), reaction frame (10), the second horizontal loader (11), the second vertical loader (12), four bearing plates (13) and second steel plate (15) are formed, it is characterized in that: the lower end, both sides of reaction frame (10) is fixed on the ground (14), the second vertical loader (12) is fixed on the ground (14) of the interior center of reaction frame (10), the first vertical loader (9) is fixed on the downside of reaction frame (10) crossbeam center, the free end of the first vertical loader (9) and the second vertical loader (12) be oppositely arranged up and down and axis identical, first steel plate (8) and second steel plate (15) are arranged in parallel, be provided with four screw rods (6) between first steel plate (8) and second steel plate (15) and form a rectangular frame, this framework is arranged on the inboard center of reaction frame (10), the first horizontal loader (7) and the second horizontal loader (11) are separately fixed on the medial surface of first steel plate (8) and second steel plate (15), the free end of the first horizontal loader (7) and the second horizontal loader (11) be oppositely arranged and axis identical, first fixed pulley (1) is arranged on the top of reaction frame (10), second fixed pulley (2) is arranged on the outside on reaction frame (10) top, one end of wire rope (3) is connected with the screw rod (6) of first steel plate (8) with second steel plate (15) upside, the other end of wire rope (3) is connected the free end of the first horizontal loader (7) through first fixed pulley (1) with second fixed pulley (2) with mass (4), the free end of the second horizontal loader (11), be equipped with a bearing plate (13) on the free end of the free end of the first vertical loader (9) and the second horizontal loader (11).

2, concrete plane complicated applied force test device according to claim 1 is characterized in that: the outside of first fixed pulley (1) is that the descending track of wire rope (3) is identical with the axis of the first vertical loader (9) and the second vertical loader (12).

3, concrete plane complicated applied force test device according to claim 2, it is characterized in that: bearing plate (13) is made up of substrate (17), backing plate (18) and sleeve (19), one side of substrate (17) is provided with convex spherical crown (16), backing plate (18) is provided with the concave surface (20) that matches with convex spherical crown (16), substrate (17) is connected with sleeve (19) with the corresponding setting of backing plate (18), backing plate (18).

4, concrete plane complicated applied force test device according to claim 3 is characterized in that: the section radius of convex spherical crown (16) is 70～80mm.

5, concrete plane complicated applied force test device according to claim 4 is characterized in that: the sphere curvature radius of convex spherical crown (16) is 190～210mm.

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