CN103994969B - Test apparatus and test method for contact characteristics of soil and structures under joint hydraulic action - Google Patents

Abstract

Soil and the contact performance test instrument of works and test method under a kind of waterpower acting in conjunction.In dam operational process, storehouse, upstream water along the surface of contact generation seepage flow between soil and works, and can form certain effect of water pressure on the contact surface.Shear stress under the effect of water pressure on surface of contact and shearing strength can change, and the mechanical response being not only different from the soil body but also being different from structure occurs, and these responses finally can cause negative effect in various degree to engineering structure.This test instrument improves conventional direct shear apparatus, primarily of cutting box, vertical loading motor, level to parts compositions such as loading motor, water pressure control system, data acquisition system (DAS), self-reaction force framves, and simple structure, easy to use.Soil and the contact shear test of works can be carried out under different hydraulics, study the contact performance of soil and works under different hydraulics.

Description

Test apparatus and test method for contact characteristics of soil and structures under joint hydraulic action

technical field

The invention belongs to the technical field of testing instruments and methods, and in particular relates to a contact characteristic tester and a test method for soil and structures under the combined action of hydraulic forces.

Background technique

According to the statistics of China Large Dam Commission, by the end of 2003, 41,418 dams with a height of 15 meters or more had been built worldwide, of which 33,958 were earth-rock dams, accounting for 82.7% of the total. In the past ten years, with the development of large-capacity, multi-functional, high-efficiency construction machinery and the progress of geotechnical engineering test methods and computing technology, my country's earth-rock dam projects have been greatly developed. By the end of 2005, China's 30-meter-high There are 4,860 dams under construction and 2,865 earth-rock dams, accounting for about 59%. During the construction of these earth-rock dams, the contact problem between soil and structures will inevitably be encountered. The study of soil-structure contact surface characteristics has always been one of the important topics in the field of civil engineering and geotechnical engineering, and it is the premise to solve the interaction between soil and structure. Because the research involves many aspects of soil mechanics and foundation engineering, it is very difficult. At present, the commonly used test methods for studying the characteristics of the contact surface are (1) large-scale contact surface direct shear instrument, which is suitable for the internal friction characteristics of various materials such as concrete materials, soil and stone, and is especially suitable for the relationship between different materials such as concrete materials and soil and stone, Research on the mechanical properties and deformation mechanism of the braided contact surface. Its disadvantage is that it cannot consider the influence of water pressure on the mechanical properties and deformation mechanism of the contact surface; (2) the large-scale contact surface characteristic direct shear instrument under cyclic load, the advantage of this equipment is that it can apply cyclic loads of different frequencies and amplitudes, the disadvantage is that the cost Expensive and inconvenient to operate; (3) An experimental device for measuring the seepage and erosion characteristics of the contact surface between soil and structure. To provide basic experimental data for analyzing the anti-seepage scour capacity of soil under different stress conditions, the disadvantage is that it does not consider the influence of soil deformation on contact seepage scour under shear stress conditions.

Contents of the invention

The object of the present invention is to provide a kind of contact characteristic tester and test method of soil and structure under the joint action of hydraulic power, this equipment can carry out the contact shear test of soil and structure under different water pressure conditions, research under different hydraulic conditions Shear properties of contact surfaces.

The purpose of the present invention is achieved through the following technical solutions:

A contact characteristic tester for soil and concrete structures under the combined action of hydraulic power, characterized in that the tester consists of a rigid dowel bar 1, a pressure plate 2, a roller 3, a top cover 4, a shear frame 5, and a concrete structure Test piece 6, permeable stone 7, rigid bottom plate 8, rubber tube 9, water pressure control system 10, horizontal displacement sensor 11, rigid connecting rod 12, horizontal tension pressure sensor 13, horizontal loading motor 14, vertical loading motor 15. Made of vertical displacement sensor 16, vertical pressure sensor 17, self-reflexive force frame 18, data acquisition system 19, motor servo controller 20, and detachable roller 21; wherein rigid base plate 8, horizontal loading motor 14 and the vertical loading motor 15 are fixedly installed on the self-reflexive force frame 18 with bolts respectively, the horizontal loading motor 14 and the vertical loading motor 15 are respectively connected to the motor servo controller 20 with wires, and the concrete structure specimen 6 is placed on a rigid On the bottom plate 8, a cavity is set in the concrete structure test piece 6, filled with a water-permeable stone 7, and a water hole is arranged on the concrete structure 6 test piece on the upper part of the water-permeable stone 7, and one end of the rubber tube 9 is connected to the water-permeable stone, and Through the rigid base plate 8, the other end is connected to the hydraulic control system 10, the shear frame 5 is placed on the concrete structure specimen 6, and the horizontal tension pressure sensor 13 is connected through the rigid connecting rod 12, and then connected to the horizontal loading motor 14. Detachable rollers 21 are provided between both sides of the shearing frame 5 and the concrete structure specimen 6, the top cover 4 is placed on the shearing frame 5, the rollers 3 are installed between the top cover 4 and the pressure plate 2, and the The pressure plate 2 and the rigid dowel bar 1 are connected by threads, the upper surface of the pressure plate 2 is in contact with the working end of the vertical displacement sensor 16, the vertical pressure sensor 17 is fixed on the vertical loading motor 15, and the horizontal displacement The sensor 11 is fixed on the self-reflexive force frame 18 with bolts, and the horizontal tension pressure sensor 13, the horizontal displacement sensor 11, the vertical pressure sensor 17 and the vertical displacement sensor 16 are connected to the data acquisition system 19 with data lines respectively.

The above-mentioned contact characteristic tester between soil and concrete structure under combined hydraulic force is characterized in that a square cavity is set in the concrete structure test piece 6, and the cavity is filled with permeable stones 7.

The described contact characteristic tester between soil and concrete structure under hydraulic interaction is characterized in that water holes are evenly arranged in the concrete structure test piece 6 on the upper part of the permeable stone 7, which directly leads to the concrete structure test piece 6 upper surface.

The method for testing with the contact characteristic tester of soil and concrete structure under the described hydraulic interaction is characterized in that the steps of the shear test method for the contact surface of soil and concrete structure without considering the influence of water pressure are as follows:

(a) prepare sample, the soil sample of known mass, density and water content is packed in shear frame 5;

(b) Adjust the tester, place the top cover 4, install the pressure plate 2, the rigid dowel bar 1, the horizontal pull pressure sensor 13 and the vertical pressure sensor 17, so that the working end of the vertical pressure sensor 17 is just in line with the The tops of the rigid dowel bars 1 are in contact;

(c) adjust the data acquisition system, install the horizontal displacement sensor 11 and the vertical displacement sensor 16, make the working section of the horizontal displacement sensor 11 contact with the right side of the shearing frame 5, and the working end of the vertical displacement sensor 16 and The top surface of the pressure plate 2 is in contact, connect the motor servo controller 20 and the data acquisition system 19, and check whether it works normally;

(d) Apply a load, start the motor servo controller 20, use the vertical loading motor 15 to apply a vertical load, according to the experimental requirements, set the load size, use the horizontal loading motor 14 to apply horizontal shear, set the horizontal shear rate and maximum shear displacement;

(e) data recording, during the test, record the variation curve of horizontal shear stress, horizontal displacement and vertical displacement with time by data acquisition system 19;

(f) At the end of the test, when the experimental shear displacement reaches the maximum shear displacement, the test is terminated.

The method for testing with the contact characteristic tester of soil and concrete structure under the described hydraulic interaction is characterized in that the steps of the shear test method for the contact surface of soil and concrete structure considering the influence of water pressure are as follows:

(a) prepare sample, the soil sample of known mass, density and water content is packed in shear frame 5;

(b) Adjust the tester, place the top cover 4, install the pressure plate 2, the rigid dowel bar 1, the horizontal pull pressure sensor 13 and the vertical pressure sensor 17, so that the working end of the vertical pressure sensor 17 is just in line with the The tops of the rigid dowel bars 1 are in contact;

(c) adjust the data acquisition system, install the horizontal displacement sensor 11 and the vertical displacement sensor 16, make the working section of the horizontal displacement sensor 11 contact with the right side of the shearing frame 5, and the working end of the vertical displacement sensor 16 and The top surface of the pressure plate 2 is in contact, connect the motor servo controller 20 and the data acquisition system 19, and check whether it works normally;

(d) apply water pressure, start the water pressure control system 10, set the water head value, water flows into the water hole through the rubber tube 9 and the permeable stone 7, and then the water pressure is evenly distributed between the soil and the concrete structure test piece 6 On the contact surface, ensure that the water pressure on the contact surface is maintained at the set value;

(e) Apply a load, start the motor servo controller 20, use the vertical loading motor 15 to apply a vertical load, according to the experimental requirements, set the load size, use the horizontal loading motor 14 to apply horizontal shear, set the horizontal shear rate and maximum shear displacement;

(f) data record, keep water pressure constant during the test, record the variation curve of horizontal shear stress, horizontal displacement and vertical displacement with time by data acquisition system 19;

(g) At the end of the test, when the test shear displacement reaches the maximum shear displacement, the test is terminated.

Through the above technical solutions, the following beneficial effects can be achieved:

(1) A variety of experiments can be carried out, not only the ordinary soil-structure contact surface shear test, but also the soil-structure contact surface shear test under water pressure conditions;

(2) There are rollers between the pressure plate and the top cover, and there are also detachable rollers between the two sides of the shearing frame and the structure, which reduces the error caused by friction;

(3) When using this equipment for testing, the load application and data recording are all automatically completed by the computer, which is convenient, fast and safe to use.

Description of drawings

Fig. 1 Schematic diagram of the structure of a tester for the contact characteristics of soil and concrete structures under the combined action of hydraulic forces

Fig. 2 cut frame top view of the present invention

Fig. 3 distribution diagram of permeable stone of the present invention

Figure 4 The shear frame and the side view of the concrete structure specimen

Reference signs: 1-rigid dowel bar, 2-pressure plate, 3-roller, 4-top cover, 5-shear frame, 6-concrete structure test piece, 7-permeable stone, 8-rigid bottom plate, 9-rubber tube, 10-water pressure control system, 11-horizontal displacement sensor, 12-rigid connecting rod, 13-horizontal tension pressure sensor, 14-horizontal loading motor, 15-vertical loading motor, 16-vertical Axial displacement sensor, 17-vertical pressure sensor, 18-reflexive force frame, 19-data acquisition system, 20-motor servo controller, 21-detachable roller.

detailed description

The specific embodiment of the present invention is described in detail below in conjunction with accompanying drawing

Example 1: A contact characteristic tester for soil and concrete structures under the combined action of hydraulic forces

As shown in Figure 1, a tester for the contact characteristics of soil and concrete structures under the combined action of hydraulic forces. It is characterized in that the tester consists of a rigid dowel bar 1, a pressure plate 2, a roller 3, a top cover 4, a shear frame 5, a concrete structure specimen 6, a permeable stone 7, a rigid bottom plate 8, a rubber tube 9, a water Pressure control system 10, horizontal displacement sensor 11, rigid connecting rod 12, horizontal tension pressure sensor 13, horizontal loading motor 14, vertical loading motor 15, vertical displacement sensor 16, vertical pressure sensor 17, reflexive force frame 18, data acquisition system 19, motor servo controller 20, and detachable rollers 21; wherein the rigid base plate 8, the horizontal loading motor 14 and the vertical loading motor 15 are respectively bolted to the self-reflexive force frame 18 Above, the horizontal loading motor 14 and the vertical loading motor 15 are respectively connected to the motor servo controller 20 with wires, the concrete structure test piece 6 is placed on the rigid base plate 8, and a cavity is arranged in the concrete structure test piece 6, Fill the permeable stone 7, the upper part of the permeable stone 7 is provided with a water hole on the concrete structure test piece 6, one end of the rubber tube 9 is connected to the permeable stone, and runs through the rigid bottom plate 8, and the other end is connected to the water pressure control system 10. The frame 5 is placed on the concrete structure test piece 6, and is connected to the horizontal tensile pressure sensor 13 through the rigid connecting rod 12, and then connected to the horizontal loading motor 14, between both sides of the shear frame 5 and the concrete structure test piece 6 A detachable roller 21 is provided, a top cover 4 is placed on the shearing frame 5, a roller 3 is installed between the top cover 4 and the pressure plate 2, and the pressure plate 2 and the rigid dowel bar 1 are connected by threads to pressurize The upper surface of the plate 2 is in contact with the working end of the vertical displacement sensor 16, the vertical pressure sensor 17 is fixed on the vertical loading motor 15, the horizontal displacement sensor 11 is fixed on the self-reflexive force frame 18 with bolts, and the horizontal pulling pressure The sensor 13 , the horizontal displacement sensor 11 , the vertical pressure sensor 17 and the vertical displacement sensor 16 are respectively connected to the data acquisition system 19 with data lines.

The above-mentioned contact characteristic tester between soil and concrete structure under combined hydraulic force is characterized in that a square cavity is set in the concrete structure test piece 6, and the cavity is filled with permeable stones 7.

The described contact characteristic tester between soil and concrete structure under hydraulic interaction is characterized in that water holes are evenly arranged in the concrete structure test piece 6 on the upper part of the permeable stone 7, which directly leads to the concrete structure test piece 6 upper surface.

in:

(1) The rigid dowel bar 1 is made of a stainless steel column with a diameter of 30 mm, and is connected to the pressure plate 2 through threads;

(2) The pressure plate 2 is made of steel plate, 25mm thick, 200mm long, and 200mm wide;

(3) The roller 3 is cut from a steel column, with a diameter of 20mm and a height of 20mm, and the roller 3 is fixed on the top cover 4;

(4) top cover 4 is made of steel plate, thick 25mm, long 200mm, wide 200mm;

(5) The shear frame 5 is welded by steel plates, the outer frame is a square with a side length of 230mm, the inner frame is a square with a side length of 200mm, the frame thickness is 15mm, and the frame height is 100mm. A certain space is required to ensure that the top cover 4 will not touch the cutting frame;

(6) Concrete structure specimen 6 is made of concrete pouring, size: length 350mm×width 350mm×height 100mm, internal cavity size: length 200mm×width 200mm×height 10mm, the cavity is filled with 25 pieces of length 40mm× The permeable stone 7 with a width of 40mm×10mm in height just fills the cavity, and the upper part of the permeable stone 7 is distributed with 4×4 circular water holes, each with a diameter of 3mm;

(7) Rigid bottom plate 8 is made of steel plate, length 500mm×width 400mm×thickness 30mm, the right side of the bottom plate has a protrusion of length 400mm×width 25mm×height 10mm, which blocks the concrete structure test piece 6 and prevents it from sliding;

(8) The rubber tube 9 is connected to the permeable stone 7 and the water pressure control system 10, the diameter of the part extending into the structure is 20mm, and the diameter of the part protruding from the rigid bottom plate is 10mm;

(9) The water pressure control system 10 can adopt the type TCK-1 triaxial test measurement controller;

(10) The rigid connecting rod 12 is made of a stainless steel column with a diameter of 40mm, the left end is fixed on the shear frame 5 by screws, and the right end is provided with a screw thread to be connected with the horizontal tension pressure sensor 13;

(11) Both the horizontal pull pressure sensor 13 and the vertical pressure sensor 17 are BLR-1 load cells, the maximum weighing capacity is 10t, and the NH accuracy level is D0.2;

(12) Horizontal loading motor 14 and vertical loading motor 15 are all Mitsubishi Electrics of power 750W;

(13) Both the horizontal displacement sensor 11 and the vertical displacement sensor 16 are TKA-50-11 straight-slide conductive plastic potentiometers, with a resistance value of 5K ohms and an independent linearity of 0.1%;

(14) The self-reflexive force frame 18 is welded by 12 pieces of angle steel, wherein the upper and lower sides are rectangular, welded with 2 pieces of angle steel with a length of 1.2m and a width of 0.6m, and vertically use 4 pieces of angle steel with a length of 1.2m and the upper Two rectangular frames are welded, and then 8 triangular steel plates are welded to the 8 corners for reinforcement;

(15) Data acquisition system 19 is made up of computer, TKA load/displacement data collector;

(16) The motor servo controller 20 is a ZJ-300 type specimen shearing system;

(17) detachable roller 21, long 250mm * wide 20mm * high 3mm.

Embodiment 2: the method that the contact characteristic tester of soil and concrete structure under the described hydraulic interaction is tested, it is characterized in that the soil and concrete structure interface shear test method step that does not consider water pressure influence is as follows:

(1) prepare sample, the quality 7.64kg that will moisture content be 9.5%, the soil sample that density is 1.91g/cm ³ is packed in shearing frame 5;

(2) Adjust the tester, place the top cover 4, install the pressure plate 2, the rigid dowel bar 1, the horizontal pull pressure sensor 13 and the vertical pressure sensor 17, so that the working end of the vertical pressure sensor 17 is just in line with the The tops of the rigid dowel bars 1 are in contact;

(3) adjust the data acquisition system, install the horizontal displacement sensor 11 and the vertical displacement sensor 16, make the working section of the horizontal displacement sensor 11 contact with the shearing frame 5 right sides, the working end of the vertical displacement sensor 16 is in contact with the shearing frame 5 right side The top surface of the pressure plate 2 is in contact, connect the motor servo controller 20 and the data acquisition system 19, and check whether it works normally;

(4) Apply a load, start the motor servo controller 20, use the vertical loading motor 15 to apply the vertical load, according to the experimental requirements, set the load size to be 40kN, use the horizontal loading motor 14 to apply horizontal shear force, set the horizontal direction The shear rate is 1mm/min, and the maximum shear displacement is 15mm;

(5) data recording, during the test, record the variation curve of horizontal shear stress, horizontal displacement and vertical displacement with time by data acquisition system 19;

(6) At the end of the test, when the experimental shear displacement reaches 15mm, the test is terminated.

Embodiment 3: the method that the contact property tester of soil and concrete structure under the described hydraulic interaction is tested, it is characterized in that the soil and concrete structure contact surface shear test method step that considers water pressure influence is as follows:

(1) (2) (3) with embodiment 2;

(4) Apply water pressure, start the water pressure control system 10, set the water head value to 100kPa, and the water flows into the water hole through the rubber tube 9 and the permeable stone 7, so that the water pressure is distributed on the soil and concrete structure specimen 6 On the contact surface, ensure that the water pressure on the contact surface is maintained at 100kPa;

(5) Apply a load, start the motor servo controller 20, use the vertical loading motor 15 to apply a vertical load, according to the experimental requirements, set the load size to 40kN, use the horizontal loading motor 14 to apply horizontal shear force, set the horizontal direction The shear rate is 1mm/min, and the maximum shear displacement is 15mm;

(6) data record, keep water pressure constant in the test process, record the change curve of horizontal shear stress, horizontal displacement and vertical displacement with time by data acquisition system 19;

(7) At the end of the test, when the experimental shear displacement reaches 15mm, the test is terminated.

Claims (5)

1. A contact characteristic tester of soil and concrete structures under a hydraulic joint action, it is characterized in that this tester is made of rigid dowel bar (1), pressure plate (2), roller (3), top cover (4) ), shear frame (5), concrete structure specimen (6), permeable stone (7), rigid base plate (8), rubber tube (9), water pressure control system (10), horizontal displacement sensor (11 ), rigid connecting rod (12), horizontal tension pressure sensor (13), horizontal loading motor (14), vertical loading motor (15), vertical displacement sensor (16), vertical pressure sensor (17), It is made of self-reflexive force frame (18), data acquisition system (19), motor servo controller (20), detachable roller (21); wherein rigid base plate (8), horizontal loading motor (14) and vertical The loading motors (15) are fixedly installed on the self-reflexive force frame (18) with bolts respectively, the horizontal loading motors (14) and the vertical loading motors (15) are respectively connected to the motor servo controller (20) with wires, and the concrete The structure test piece (6) is placed on the rigid base plate (8), a cavity is set in the concrete structure test piece (6), and the permeable stone (7) is filled, and the concrete structure test piece above the permeable stone (7) (6) is arranged with a water hole, one end of the rubber tube (9) is connected to the permeable stone, and runs through the rigid bottom plate (8), the other end is connected to the water pressure control system (10), and the shear frame (5) is placed on the concrete on the structure test piece (6), and connect the horizontal tension pressure sensor (13) through the rigid connecting rod (12), and then connect the horizontal loading motor (14), the two sides of the shear frame (5) and the concrete structure A detachable roller (21) is provided between the test pieces (6), a top cover (4) is placed on the shear frame (5), and a roller (3) is installed between the top cover (4) and the pressure plate (2) , the pressure plate (2) is threadedly connected with the rigid dowel bar (1), the upper surface of the pressure plate (2) is in contact with the working end of the vertical displacement sensor (16), and the vertical pressure sensor (17) Be fixed on the vertical loading motor (15), the horizontal displacement sensor (11) is fixed on the self-reflexive force frame (18) with bolts, the horizontal pulling pressure sensor (13), the horizontal displacement sensor (11), the vertical The pressure sensor (17) and the vertical displacement sensor (16) are respectively connected with the data acquisition system (19) by data lines. 2. the contact characteristic tester of soil and concrete structure under a kind of hydraulic interaction according to claim 1, it is characterized in that a square cavity is set in the described concrete structure test piece (6), in the cavity Fill the water stone (7). 3. the contact characteristic tester of soil and concrete structure under a kind of hydraulic interaction according to claim 1, it is characterized in that in described water-permeable stone (7) top concrete structure test piece (6) is evenly arranged with The water hole is directly connected to the upper surface of the concrete structure test piece (6). 4. a method that uses the contact characteristic tester of soil and concrete structure under the hydraulic interaction described in claim 1 to test, it is characterized in that the soil and concrete structure contact surface shear test method that does not consider water pressure influence Proceed as follows: (a) prepare sample, put the soil sample of known mass, density and water content in the shearing frame (5); (b) Adjust the tester, place the top cover (4), install the pressure plate (2), the rigid dowel bar (1), the horizontal tension pressure sensor (13) and the vertical pressure sensor (17), so that The working end of the vertical pressure sensor (17) is just in contact with the top of the rigid dowel bar (1); (c) Adjust the data acquisition system, install the horizontal displacement sensor (11) and the vertical displacement sensor (16), so that the working section of the horizontal displacement sensor (11) is in contact with the right side of the shearing frame (5), vertically Contact the working end of the displacement sensor (16) with the top surface of the pressure plate (2), connect the motor servo controller (20) and the data acquisition system (19), and check whether it works normally; (d) Apply load, start the motor servo controller (20), use the vertical loading motor (15) to apply the vertical load, according to the experimental requirements, set the load size, use the horizontal loading motor (14) to apply horizontal shear force, Set the horizontal shear rate and maximum shear displacement; (e) data recording, during the test, record the variation curve of horizontal shear stress, horizontal displacement and vertical displacement with time by data acquisition system (19); (f) At the end of the test, when the experimental shear displacement reaches the maximum shear displacement, the test is terminated. 5. a method that uses the contact characteristic tester of soil and concrete structure under the hydraulic interaction described in claim 1 to test, it is characterized in that the soil and concrete structure contact surface shear test method step that considers water pressure influence as follows: (a) prepare sample, put the soil sample of known mass, density and water content in the shearing frame (5); (b) Adjust the tester, place the top cover (4), install the pressure plate (2), the rigid dowel bar (1), the horizontal tension pressure sensor (13) and the vertical pressure sensor (17), so that The working end of the vertical pressure sensor (17) is just in contact with the top of the rigid dowel bar (1); (c) Adjust the data acquisition system, install the horizontal displacement sensor (11) and the vertical displacement sensor (16), so that the working section of the horizontal displacement sensor (11) is in contact with the right side of the shearing frame (5), vertically Contact the working end of the displacement sensor (16) with the top surface of the pressure plate (2), connect the motor servo controller (20) and the data acquisition system (19), and check whether it works normally; (d) Apply water pressure, start the water pressure control system (10), set the water head value, and the water flows into the water hole through the rubber tube (9) and the permeable stone (7), so that the water pressure is evenly distributed in the soil and concrete On the contact surface of the structure test piece (6), ensure that the water pressure on the contact surface is maintained at the set value; (e) Apply load, start the motor servo controller (20), use the vertical loading motor (15) to apply the vertical load, according to the experimental requirements, set the load size, use the horizontal loading motor (14) to apply horizontal shear force, Set the horizontal shear rate and maximum shear displacement; (f) data record, keep water pressure constant during the test, record the variation curve of horizontal shear stress, horizontal displacement and vertical displacement with time by data acquisition system (19); (g) At the end of the test, when the test shear displacement reaches the maximum shear displacement, the test is terminated.