A testing system and testing method suitable for reinforced concrete pipes

Abstract

The present application relates to reinforced concrete pipeline testing technical field, especially in kind, a kind of testing system and testing method suitable for reinforced concrete pipeline, comprising: pedestal, for carrying reinforced concrete pipeline;Loading device, for the reinforced concrete pipeline is applied load;And, in the inner cavity of the reinforced concrete pipeline, two groups of laser displacement meters are arranged in parallel, for detecting the vertical direction displacement of the reinforced concrete pipeline when load is applied;And, at the end of the reinforced concrete pipeline, two pull rope type displacement meters are symmetrically arranged, for detecting the horizontal direction displacement of the reinforced concrete pipeline when load is applied.The present application can effectively eliminate the influence of the deformation of displacement meter support, so that the deformation of reinforced concrete pipeline is more real, the reinforced concrete pipeline test is more accurate, the scientificity of reinforced concrete pipeline mechanical loading test can be improved, the test result is enriched, and the measurement method is standardized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of reinforced concrete pipe testing, in particular to a testing system and method suitable for reinforced concrete pipes. BACKGROUND

[0002] Reinforced concrete pipes (RCP) are widely used for the transportation of sewage and stormwater due to their good stiffness, durability and mechanical bearing capacity. Therefore, the study of the mechanical bearing capacity of concrete pipes has always been a hot issue in the industry.

[0003] The indirect design method is a commonly used design method for the bearing capacity of concrete pipes. This method uses a standard three-edge bearing test (TEBT) on reinforced concrete pipes (RCP) to evaluate their bearing capacity in buried environments.

[0004] When using the three-edge bearing test (TEBT) to test the mechanical properties of reinforced concrete pipes (RCP), it is necessary to place them on a base made of wooden boards, and then apply a line load directly above them. According to the three-edge bearing test (TEBT), the crack load and ultimate load of the concrete pipe can be obtained.

[0005] The crack load is defined as the load corresponding to the appearance of a crack in the reinforced concrete pipe (RCP) structure with a width of 0.01 inches (0.25 mm) and a length of not less than 30 cm. Finding such a characteristic crack during the experiment is an important task. However, in the prior art, finding the target crack still requires manual observation to find the crack, and then measuring it with a leaf gauge. Due to factors such as the observer's attention and vision, the results obtained by this method are too subjective and non-reproducible.

[0006] In addition, in the existing testing technology, when performing the three-edge bearing test (TEBT) on the reinforced concrete pipe (RCP), there is a lack of accurate monitoring technology for the deformation of its ring section, which leads to the fact that when analyzing the bearing capacity performance of the reinforced concrete pipe (RCP), there are only two indicators of crack load and ultimate load, which cannot reflect its stiffness and toughness. SUMMARY

[0007] In order to solve the technical problems of strong subjectivity, low testing accuracy and single testing index in the existing reinforced concrete pipe testing technology, an embodiment of the present application provides a testing system suitable for reinforced concrete pipes, which comprises:

[0008] a base for bearing the reinforced concrete pipe;

[0009] a loading device for applying a load to the reinforced concrete pipe;

[0010] and, in the inner cavity of the reinforced concrete pipe, two groups of laser displacement meters are arranged in parallel to detect the vertical displacement of the reinforced concrete pipe under load;

[0011] and, at the end of the reinforced concrete pipe, two tensioned pull ropes are arranged between two pull rope displacement meters to detect the horizontal displacement of the reinforced concrete pipe under load.

[0012] In some preferred embodiments, the two groups of laser displacement meters are located on a vertical plane passing through the central axis of the reinforced concrete pipe.

[0013] The two tensioned pull ropes are arranged between the two pull rope displacement meters, and the pull ropes are parallel to a horizontal plane passing through the central axis of the reinforced concrete pipe.

[0014] In some preferred embodiments, the test system further comprises:

[0015] a displacement meter support on which the two groups of laser displacement meters are arranged in parallel;

[0016] a fixed clamp assembly by which the two pull rope displacement meters are fixed at the end of the reinforced concrete pipe.

[0017] In some preferred embodiments, the displacement meter support comprises an upper crossbeam and a lower crossbeam, and a first vertical column and a second vertical column.

[0018] The two groups of laser displacement meters are respectively mounted on the upper crossbeam and the lower crossbeam, and the distance between the upper crossbeam and the lower crossbeam and the central axis of the reinforced concrete pipe is equal.

[0019] The first vertical column and the second vertical column are respectively arranged on both sides of the end of the reinforced concrete pipe, the upper crossbeam connects the first vertical column and the second vertical column, and the lower crossbeam connects the first vertical column and the second vertical column.

[0020] In some preferred embodiments, the fixed clamp assembly comprises an L-shaped platform and a G-shaped clamp.

[0021] The G-shaped clamp clamps and fixes the longitudinal arm of the L-shaped platform and the pipe wall at the end of the reinforced concrete pipe, and the pull rope displacement meter is fixed on the transverse arm of the L-shaped platform.

[0022] In some preferred embodiments, each group of laser displacement meters is arranged at least one, and the number of the two groups of laser displacement meters is the same.

[0023] In some preferable embodiments, the loading device comprises a counterforce frame, an actuator connecting the counterforce frame and an adapter beam, and a loading beam arranged at the bottom of the adapter beam.

[0024] The loading beam is arranged at the middle position of the adapter beam.

[0025] The loading beam is in soft contact with the outer wall of the reinforced concrete pipe.

[0026] In some preferable embodiments, the actuator is two, and the two actuators are symmetrically arranged relative to the central axis of the adapter beam.

[0027] In some preferable embodiments, the base comprises two wooden square bases, the sidewall of the wooden square base is provided with a plurality of threaded through holes, and the two wooden square bases are connected by a limiting bolt.

[0028] The distance h between the two wooden square bases is adjusted by the limiting bolt, wherein h = 0.1R, and R is the outer diameter of the reinforced concrete pipe.

[0029] Another embodiment of the present application provides a testing method suitable for a reinforced concrete pipe, which comprises the following method steps:

[0030] S1: The distance between the two wooden square bases is adjusted to 10% of the outer diameter of the reinforced concrete pipe, and a ground tank is placed below each of the four corners of the base formed by the two wooden square bases.

[0031] S2: The reinforced concrete pipe is hoisted to the wooden square bases, the reinforced concrete pipe is pushed to the position below the loading device by the ground tank, the position is adjusted so that the central axis of the reinforced concrete pipe is aligned with the center line of the loading beam, the reinforced concrete pipe is hoisted by a gantry crane, and the ground tank is removed, and then the reinforced concrete pipe is dropped.

[0032] S3: An upper beam and a lower beam are respectively installed on the first column and the second column, and an equal number of laser displacement meters are respectively installed on the upper beam and the lower beam, wherein the upper beam and the lower beam pass through the inner cavity of the reinforced concrete pipe.

[0033] S4: The height and position of the upper beam and the lower beam are adjusted, wherein the plane formed by the upper beam and the lower beam is located in the same plane as the vertical plane passing through the central axis of the reinforced concrete pipe.

[0034] The distance between the upper beam and the lower beam and the central axis of the reinforced concrete pipe is equal.

[0035] S5: installing two pull rope displacement gauges through the pipe wall at the end of the reinforced concrete pipeline by the fixing clamp assembly, arranging a tensioned pull rope between the two pull rope displacement gauges, and the pull rope is parallel to the horizontal plane passing through the central axis of the reinforced concrete pipeline;

[0036] S6: the loading device is loaded, each laser displacement gauge records the vertical direction displacement of the reinforced concrete pipeline, and each pull rope displacement gauge records the horizontal direction displacement of the reinforced concrete pipeline;

[0037] S7: after the loading is completed, a loading time-force curve and a displacement-force curve are drawn, and the performance of the reinforced concrete pipeline is analyzed through the drawn loading time-force curve and displacement-force curve.

[0038] The technical scheme provided by the embodiment of the present application has at least the following beneficial effects:

[0039] The present application provides a testing system and method suitable for reinforced concrete pipelines, two groups of laser displacement gauges are used to record the vertical direction displacement data of the reinforced concrete pipeline, and after the data measured by the two groups of laser displacement gauges are processed, the influence of the deformation of the displacement gauge support can be effectively eliminated, so that the deformation of the reinforced concrete pipeline is more real, and the reinforced concrete pipeline test is more accurate.

[0040] The present application provides a testing system and method suitable for reinforced concrete pipelines, two groups of laser displacement gauges are used to record the vertical direction displacement data of the reinforced concrete pipeline, and after the data measured by the two groups of laser displacement gauges are processed, the influence of the deformation of the displacement gauge support can be effectively eliminated, so that the deformation of the reinforced concrete pipeline is more real, and the reinforced concrete pipeline test is more accurate.

[0041] The present application provides a testing system and method suitable for reinforced concrete pipelines, the height of the upper cross beam and the lower cross beam can be adjusted to cooperate with the testing of different models of reinforced concrete pipelines.

[0042] The present application provides a testing system and method suitable for reinforced concrete pipelines, since the cross section of the reinforced concrete pipeline is circular, unilateral stress is easy to be too heavy during loading, so that the reinforced concrete pipeline slips out of the base, in order to avoid the above situation, the number of actuators is two and symmetrically arranged, so that the reinforced concrete pipeline is uniformly stressed on both sides during loading, and is not easy to leave the base.

[0043] The present application provides a testing system and method suitable for reinforced concrete pipelines, the laser displacement gauge and the pull rope displacement gauge respectively acquire the vertical direction displacement and the horizontal direction displacement of the cross section of the reinforced concrete pipeline, and the ring stiffness, failure energy and other performances are calculated and analyzed through the drawn force-displacement curve.

[0044] The application provides a test system and a test method suitable for a reinforced concrete pipeline, and can improve the scientificity of a mechanical loading test of the reinforced concrete pipeline, enrich test results, standardize a measurement method, provide more comprehensive test indexes, and has important significance for related research on a bearing capacity of the reinforced concrete pipeline structure. BRIEF DESCRIPTION OF DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort.

[0046] Figure 1 is a schematic diagram of a test system suitable for a reinforced concrete pipeline in an embodiment of the present application.

[0047] Figure 2 is a displacement meter distribution diagram of the test system suitable for the reinforced concrete pipeline in the embodiment of the present application.

[0048] Figure 3 is a schematic diagram of a pull rope type displacement meter measuring horizontal direction displacement of the reinforced concrete pipeline in the test system suitable for the reinforced concrete pipeline in the embodiment of the present application.

[0049] Figure 4 is a schematic diagram of the pull rope type displacement meter fixed on the reinforced concrete pipeline in the test system suitable for the reinforced concrete pipeline in the embodiment of the present application.

[0050] Figure 5 is a schematic diagram of a laser displacement meter measuring vertical direction displacement of the reinforced concrete pipeline in the test system suitable for the reinforced concrete pipeline in the embodiment of the present application. DETAILED DESCRIPTION

[0051] The technical solutions in the embodiments of the present application will be described clearly and completely with reference to the drawings of the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present application.

[0052] The terms "first", "second", "third", "fourth" and the like in the description and in the claims of the present application, if any, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the use of such terms is not to limit the scope of the embodiments described herein, which are capable of functioning in orders other than those described. Furthermore, the terms "comprise", "comprising", "include", "including", and the like, as well as any variations thereof, are intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus that comprises, includes or consists of a list of elements is not necessarily limited to those elements, but can include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0053] As Figure 1 shown in the schematic diagram of the testing system suitable for reinforced concrete pipes in one embodiment of the present application, according to the embodiments of the present application, a testing system suitable for reinforced concrete pipes comprises: a base for bearing a reinforced concrete pipe 2; and a loading device for applying a load to the reinforced concrete pipe 2. The reinforced concrete pipe 2 to be tested is laid flat on the base, the pipe wall of the reinforced concrete pipe 2 is in contact with the loading device, and the loading device is used to apply a load to the reinforced concrete pipe 2.

[0054] According to the embodiments of the present application, the base comprises two wooden square bases 1, the side walls of the wooden square bases 1 are provided with a plurality of threaded holes, and the two wooden square bases 1 are connected by limiting bolts 8. The distance h between the two wooden square bases 1 is adjusted by the limiting bolts 8, wherein h = 0.1R, and R is the outer diameter of the reinforced concrete pipe 2.

[0055] In some preferred embodiments, the wooden square bases 1 are made of two pieces of hard wood, and the edges of the wooden square bases 1 that are in contact with the reinforced concrete pipe 2 are chamfered with a circular arc to stably bear the reinforced concrete pipe 2. In further preferred embodiments, four limiting bolts 8 are arranged between the two wooden square bases 1 to control the width between the two wooden square bases 1.

[0056] The base of the present application is composed of the wooden square bases 1 and the limiting bolts 8, and the distance between the wooden square bases 1 is adjusted by the limiting bolts 8, so that the testing of different models of reinforced concrete pipes 2 can be performed.

[0057] According to the embodiments of the present application, the loading device comprises: a counterforce frame 7, an actuator 6 connecting the counterforce frame 7 and an adapter cross beam 5, and a loading beam 4 arranged at the bottom of the adapter cross beam 5. The loading beam 4 is arranged at the middle position of the adapter cross beam 5, and the loading beam 4 is in soft contact with the outer wall of the reinforced concrete pipe 2. The reinforced concrete pipe 2 is in contact with the loading beam 4 in the vertical direction directly above the loading beam 4.

[0058] In some preferred embodiments, the loading device makes flexible contact between the rubber pad 3 and the outer wall of the reinforced concrete pipe 2 to be tested by setting a rubber pad 3 at the bottom of the loading beam 4.

[0059] In some preferred embodiments, two actuators 6 are preferably arranged symmetrically with respect to the central axis of the transition beam 5. In a further preferred embodiment, the actuators 6 are preferably servo hydraulic actuators (MTS). Preferably, the two actuators 6 ensure the level of the transition beam 5 by linear displacement loading, which can prevent the reinforced concrete pipe 2 from rolling due to bias.

[0060] like Figure 2 The diagram shown is a displacement gauge distribution diagram of a testing system suitable for reinforced concrete pipes in one embodiment of the present invention. Figure 3 The diagram shows a pull-string displacement gauge used in a testing system suitable for reinforced concrete pipes according to an embodiment of the present invention for measuring the horizontal displacement of reinforced concrete pipes. Figure 4 The diagram shown illustrates a pull-string displacement gauge fixed to a reinforced concrete pipeline, part of a testing system suitable for reinforced concrete pipelines according to one embodiment of the present invention. Figure 5 The diagram shows a laser displacement meter measuring the vertical displacement of a reinforced concrete pipeline using a testing system suitable for reinforced concrete pipelines, according to one embodiment of the present invention. Figure 2 Region b is an enlarged view of region a.

[0061] According to an embodiment of the present invention, a testing system suitable for reinforced concrete pipes further includes: two sets of laser displacement gauges 12 arranged in parallel inside the reinforced concrete pipe 2 for detecting the vertical displacement of the reinforced concrete pipe 2 when a load is applied.

[0062] Two pull-rope displacement gauges 13 are symmetrically arranged at the end of the reinforced concrete pipe 2 to detect the horizontal displacement of the reinforced concrete pipe 2 when a load is applied.

[0063] Two sets of laser displacement gauges 12 are located on a vertical plane 21 passing through the central axis of the reinforced concrete pipe 2; a tensioned rope 19 is arranged between two rope displacement gauges 13, and the rope 19 is parallel to the horizontal plane 20 passing through the central axis of the reinforced concrete pipe 2.

[0064] According to an embodiment of the present invention, a testing system suitable for reinforced concrete pipes further includes: a displacement gauge support and a fixing clamp assembly.

[0065] Two sets of laser displacement gauges 12 are arranged in parallel on the displacement gauge bracket, and two rope-type displacement gauges 13 are fixed to the end of the reinforced concrete pipe 2 through a fixing clamp assembly.

[0066] In specific embodiments, the displacement meter support comprises an upper cross beam 11 and a lower cross beam 10, and a first vertical column 9 and a second vertical column 16. Two groups of laser displacement meters 12 are respectively installed on the upper cross beam 11 and the lower cross beam 9, i.e. the upper group of laser displacement meters 12 are installed on the upper cross beam 11, and the lower group of laser displacement meters 12 are installed on the lower cross beam 9. In some preferred embodiments, at least one laser displacement meter 12 is arranged in each group, and the number of the two groups of laser displacement meters 12 is the same, i.e. the number of the upper group of laser displacement meters 12 is the same as that of the lower group of laser displacement meters 12, and the positions of the upper group of laser displacement meters 12 correspond to those of the lower group of laser displacement meters 12.

[0067] In some preferred embodiments, sliding platforms are arranged on the upper cross beam 11 and the lower cross beam 10, and the two groups of laser displacement meters 12 are respectively installed on the sliding platforms, so as to realize the sliding of the laser displacement meters 12 on the upper cross beam 11 and the lower cross beam 10. In further embodiments, the sliding platform can be a sliding groove, and mounting holes adapted to the bases of the laser displacement meters 12 are arranged on the sliding groove. The aperture of the mounting holes is larger than the gap of the sliding groove, the bases of the laser displacement meters 12 are embedded in the sliding groove through the mounting holes, and the inner cavity of the sliding groove supports the reciprocating sliding of the bases of the laser displacement meters 12. Based on this, a plurality of laser displacement meters 12 can be installed on the upper cross beam 11 and the lower cross beam 10 according to actual conditions.

[0068] According to the embodiments of the present application, when the reinforced concrete pipeline 2 is tested, the upper cross beam 11 and the lower cross beam 10 are inserted into the inner cavity of the reinforced concrete pipeline 2, and the distance between the upper cross beam 11 and the lower cross beam 10 and the central axis of the reinforced concrete pipeline 2 is equal.

[0069] According to the embodiments of the present application, the first vertical column 9 and the second vertical column 16 are respectively arranged on both sides of the end of the reinforced concrete pipeline 2, the upper cross beam 11 connects the first vertical column 9 and the second vertical column 16, and the lower cross beam 10 connects the first vertical column 9 and the second vertical column 16.

[0070] In some preferred embodiments, sliding rails and fixing bolts are arranged between the upper cross beam 11 and the first vertical column 9 and the second vertical column 16, and between the lower cross beam 10 and the first vertical column 9 and the second vertical column 16. The fixing bolts fix the upper cross beam 11 and the lower cross beam 10 at different heights, so as to adjust the height of the upper cross beam 11 and the lower cross beam 10. The specific height adjustment mode of the sliding rails and the fixing bolts can be selected by those skilled in the art according to specific conditions, and the present application is not limited in this regard. In further preferred embodiments, the upper cross beam 11 and the lower cross beam 10 can be detached from the first vertical column 9 and the second vertical column 16.

[0071] In a specific embodiment, the fixed clamp assembly comprises an L-shaped platform 14 and a G-shaped clamp 15. The G-shaped clamp 15 clamps the longitudinal arm of the L-shaped platform 14 to the pipe wall at the end of the reinforced concrete pipe 2, and the transverse arm of the L-shaped platform 14 is fixed with the pull rope displacement meter 13.

[0072] In a further embodiment, a G-shaped clamp 15 is arranged on each of the pipe walls at the two ends of the horizontal waist line of the reinforced concrete pipe 2, and the heights of the two G-shaped clamps 15 are the same. That is, the connecting line of the two G-shaped clamps 15 is located on the horizontal plane 20 passing through the central axis of the reinforced concrete pipe 2.

[0073] The G-shaped clamp 15 clamps the longitudinal arm of the L-shaped platform 14 to the pipe wall, so that the longitudinal arm is perpendicular to the ground. The transverse arm of the L-shaped platform 14 remains horizontal, and the pull rope displacement meter 13 is fixed on the transverse arm of the L-shaped platform 14.

[0074] According to an embodiment of the present application, a testing method suitable for reinforced concrete pipes is provided, and the method comprises the following method steps:

[0075] S1: The distance between the two wooden bases 1 is adjusted to be 10% of the outer diameter of the reinforced concrete pipe 2, and a ground tank is placed under each of the four corners of the base formed by the two wooden bases 1, wherein the support direction of at least one side of the ground tank is adjusted.

[0076] S2: The reinforced concrete pipe 2 is hoisted to the wooden base 1, and the reinforced concrete pipe 2 is pushed to the loading device by the ground tank, and the position is adjusted so that the reinforced concrete pipe 2 is aligned with the loading beam 4 directly above.

[0077] Specifically, the reinforced concrete pipe 2 is hoisted above the wooden base 1 and then placed on the base. The measured reinforced concrete pipe 2 is fixed by being placed on the gap formed by the two wooden bases 1. The central axis of the measured reinforced concrete pipe 2 after being placed horizontally is in the same vertical plane as the center line of the gap formed by the two wooden bases 1.

[0078] The ground tank is pushed to the loading device using a mechanical device such as a forklift, and the position is adjusted so that the measured reinforced concrete pipe 2 is aligned with the loading beam 4 directly above. That is, the center line of the loading beam 4 is in the same vertical plane as the central axis of the measured reinforced concrete pipe 2. Then the reinforced concrete pipe 2 is hoisted using a gantry crane, and after the ground tank is removed, the reinforced concrete pipe 2 is lowered.

[0079] S3: The upper cross beam 11 and the lower cross beam 10 are respectively installed on the first vertical column 9 and the second vertical column 16, and the same number of laser displacement meters 12 are respectively installed on the upper cross beam 11 and the lower cross beam 10, wherein the upper cross beam 11 and the lower cross beam 10 pass through the inner cavity of the reinforced concrete pipe 2.

[0080] In a specific embodiment, the number of laser displacement meters 12 is set according to the length of the reinforced concrete pipe 2 to be measured and the requirements.

[0081] S4: Adjust the height and position of the upper cross beam 11 and the lower cross beam 10, wherein the plane formed by the upper cross beam 11 and the lower cross beam 10 is in the same plane as the vertical plane 21 passing through the axis of the reinforced concrete pipe 2. The distance between the upper cross beam 11 and the lower cross beam 10 and the axis of the reinforced concrete pipe 2 is equal, and it is ensured that the upper group of laser displacement meters 12a is within the range of the top 17 of the reinforced concrete pipe 2, and the lower group of laser displacement meters 12b is within the range of the bottom 18 of the reinforced concrete pipe 2.

[0082] S5: Install two pull rope displacement meters 13 on the pipe wall at the end of the reinforced concrete pipe 2 through the fixed clamp assembly, arrange a tensioned pull rope 19 between the two pull rope displacement meters 13, and the pull rope 19 is parallel to the horizontal plane 20 passing through the axis of the reinforced concrete pipe 2.

[0083] S6: Load the device, and each laser displacement meter 12 records the vertical displacement of the reinforced concrete pipe 2, and each pull rope displacement meter 13 records the horizontal displacement of the reinforced concrete pipe 2.

[0084] The loading process performs the loading process specified in GB / T 16752-2017 “Test Methods for Concrete and Reinforced Concrete Drainage Pipes”, and applies a load to the reinforced concrete pipe 2 to be measured, and the reinforced concrete pipe 2 generates horizontal deformation (x direction shown in FIG. 1) and vertical deformation (y direction shown in FIG. 1). Figure 3 Figure 5

[0085] For the displacement generated by the horizontal deformation of the reinforced concrete pipe 2, it is directly measured by the pull rope displacement meter 13.

[0086] For the displacement generated by the vertical deformation of the reinforced concrete pipe 2, it is calculated by the following method:

[0087] Before loading, the distance between the upper group of laser displacement meters 12a and the top 17 of the reinforced concrete pipe 2 is D, and the distance between the lower group of laser displacement meters 12b and the bottom 18 of the reinforced concrete pipe 2 is also D.

[0088] ​​When the load is applied, the distance between the upper group of laser displacement meters 12a and the top 17 of the reinforced concrete pipeline 2 is d, the distance between the lower group of laser displacement meters 12b and the bottom 18 of the reinforced concrete pipeline 2 is n, and the displacement of the upper group of laser displacement meters 12a due to its own deformation is m. Since the displacement of the upper group of laser displacement meters 12a and the lower group of laser displacement meters 12b is almost the same, it can be assumed that the displacement of the lower group of laser displacement meters 12b due to its own deformation is also m. Therefore, the vertical displacement of the reinforced concrete pipeline 2 is:

[0089] T = D - (d - m), where m = D - n, D is known, d is measured by the upper group of laser displacement meters 12a, and n is measured by the lower group of laser displacement meters 12b.

[0090] Finally, the vertical displacement of the reinforced concrete pipeline 2 is calculated by T = 2D - d - n.

[0091] S7: Draw the load time-force curve and the displacement-force curve, and analyze the performance of the reinforced concrete pipeline 2 by drawing the load time-force curve and the displacement-force curve.

[0092] By drawing the load time-force curve, the load time is taken as the horizontal coordinate and the load is taken as the vertical coordinate. The load corresponding to the first slope inflection point can be identified as the crack load.

[0093] Draw the displacement-force curve, where displacement is taken as the horizontal coordinate and load is taken as the vertical coordinate. The ring stiffness can be obtained by taking the first derivative of the displacement-force curve, and the failure energy can be obtained by integrating the area before the limit state of the ring stiffness.

[0094] The vertical coordinate in the curve drawing process should be taken as the line load, i.e. the force value per meter.

[0095] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not limited thereto. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some or all of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method of testing suitable for reinforced concrete pipes, characterized in that, The method uses a The testing system is suitable for reinforced concrete pipes and comprises a base for supporting the reinforced concrete pipe; a loading device for applying a load to the reinforced concrete pipe; two groups of laser displacement meters arranged in parallel in the inner cavity of the reinforced concrete pipe for detecting the vertical displacement of the reinforced concrete pipe under the load; and the two groups of laser displacement meters are located on a vertical plane passing through the central axis of the reinforced concrete pipe; two tensioned cable displacement meters symmetrically arranged at the ends of the reinforced concrete pipe for detecting the horizontal displacement of the reinforced concrete pipe under the load; the two tensioned cable displacement meters are fixed to the ends of the reinforced concrete pipe by a fixing clamp assembly; a displacement meter support on which the two groups of laser displacement meters are arranged in parallel; the displacement meter support comprises upper and lower crossbeams and first and second vertical columns; the two groups of laser displacement meters are respectively mounted on the upper and lower crossbeams; the first and second vertical columns are respectively arranged on the two sides of the ends of the reinforced concrete pipe, the upper crossbeam connects the first and second vertical columns, and the lower crossbeam connects the first and second vertical columns; the method comprises the following steps: S1: adjust the distance between the two wooden bases to 10% of the outer diameter of the reinforced concrete pipe, and place a ground tank under each of the four corners of the base formed by the two wooden bases; S2: hoist the reinforced concrete pipe onto the wooden bases, push the reinforced concrete pipe under the loading device by the ground tanks, and adjust the position so that the reinforced concrete pipe is aligned directly above the loading device; S3: mount the upper and lower crossbeams on the first and second vertical columns respectively, and mount the same number of laser displacement meters on the upper and lower crossbeams respectively, wherein the upper and lower crossbeams pass through the inner cavity of the reinforced concrete pipe; S4: adjust the height and position of the upper and lower crossbeams, wherein the plane formed by the upper and lower crossbeams is located on the same plane as the vertical plane passing through the central axis of the reinforced concrete pipe, and the distance between the upper and lower crossbeams and the central axis of the reinforced concrete pipe is equal; S5: install two tensioned cable displacement meters on the pipe wall at the ends of the reinforced concrete pipe by the fixing clamp assembly, arrange a tensioned cable between the two tensioned cable displacement meters, and the cable is parallel to the horizontal plane passing through the central axis of the reinforced concrete pipe; S6: the loading device applies a load, each laser displacement meter records the vertical displacement of the reinforced concrete pipe, and each tensioned cable displacement meter records the horizontal displacement of the reinforced concrete pipe; S7: draw a load-time curve and a displacement-force curve, analyze the performance of the reinforced concrete pipe by the drawn load-time curve and displacement-force curve, identify the crack load, and calculate the ring stiffness and failure energy.

2. The testing method suitable for reinforced concrete pipe according to claim 1, characterized in that, the fixed clamp assembly comprises an L-shaped platform and a G-shaped clamp; the G-shaped clamp clamps and fixes the longitudinal arm of the L-shaped platform and the pipe wall of the end of the reinforced concrete pipe, and the lateral arm of the L-shaped platform is fixed with the pull rope displacement meter.

3. A method of testing suitable for reinforced concrete pipes according to claim 1, characterized in that, Each group of the laser displacement meter is arranged at least one, and the number of two groups of the laser displacement meters is the same.

4. A method of testing suitable for reinforced concrete pipes according to claim 1, characterized in that, The loading device comprises a counterforce frame, an actuator connecting the counterforce frame and an adapter beam, and a loading beam arranged at the bottom of the adapter beam. The loading beam is arranged at the middle position of the adapter beam, the loading beam is in flexible contact with the outer wall of the reinforced concrete pipe, and the position is adjusted to align the loading beam with the reinforced concrete pipe in step S2.

5. A method of testing suitable for reinforced concrete pipes according to claim 4, characterized in that, The actuator is two, and the two actuators are symmetrically arranged relative to the central axis of the adapter beam.

6. The testing method suitable for reinforced concrete pipe according to claim 1, characterized in that, the base comprises two wooden bottom bases, the side wall of the wooden bottom base is provided with a plurality of threaded through holes, and the two wooden bottom bases are connected through limiting bolts; the distance h between the two wooden bottom bases is adjusted through the limiting bolts, wherein h=0.1R, and R is the outer diameter of the reinforced concrete pipe.

Images