CN105572037B - Method for testing relative slippage of non-metal anti-floating anchor rod and concrete interface - Google Patents

Abstract

The invention belongs to the technical field of civil engineering tests, and relates to a relative slippage test method of a non-metal anti-floating anchor rod and a concrete interface, which comprises the steps of firstly installing a relative slippage test device of the non-metal anti-floating anchor rod and the concrete interface, then calibrating a through jack and a load sensor of the relative slippage test device of the non-metal anti-floating anchor rod and the concrete interface, finally loading by using the through jack, controlling the ascending amount of the through jack to be less than 10cm, causing the displacement of an anchor rod body by the reaction force of the through jack acting on a through reaction beam, and reading of a dial indicator at the moment, namely the relative slippage of the anchor rod and the concrete interface; the method has the advantages of simple process, high test precision, strong operability, direct numerical value result, high precision and small error.

Description

A relative sliding test method of non-metal anti-floating anchor rod and concrete interface

Technical field:

The invention belongs to the technical field of civil engineering tests (including in-situ tests and indoor tests), and relates to a method for testing the relative slippage of a non-metallic anti-floating anchor rod and concrete interface. Insufficient, it can more accurately and conveniently obtain the relative slippage between the non-metallic anti-floating anchor rod and the concrete interface, which provides a basis for experimental research and material application.

Background technique:

With the development and utilization of urban underground space and the continuous increase of building height, the foundation burial depth of buildings is also increasing. When the structural load cannot resist the buoyancy of groundwater, the problem of anti-floating becomes more and more prominent. In engineering, we generally use methods such as drainage method, weight method, anti-floating piles, anti-floating anchors and other methods to achieve the purpose of anti-floating. Compared with other methods, anti-floating anchors have strong stratum adaptability and disperse stress. , easy construction, high bearing capacity in hard rock and soil layers, short construction period, low cost and other advantages and is widely used. With the application of non-metallic materials such as glass fiber in underground engineering, the anti-floating anchor rod has the characteristics of corrosion resistance and anti-electromagnetic interference, which solves the problem that plagues the rock and soil anchoring field; due to the construction of urban subway projects and Vigorous development, non-metallic anti-floating anchors have solved the problem of anti-electromagnetic interference on the anti-floating issue of anchors in subway construction, making them have broader application prospects and research significance. Bearing capacity and deformation are the two most important control indicators in underground engineering construction. In some projects, deformation is more important than bearing capacity. The anti-floating anchor is anchored into a reinforced concrete floor with a certain thickness. The sliding performance of the anchor and concrete directly affects the bearing capacity and deformation of structural members, and it is of great significance to determine the external anchorage length of the anti-floating anchor. Therefore, in During the test, it is particularly important to directly measure the relative slip between the non-metallic anti-floating anchor rod and the concrete, and the key is the accuracy and simplicity of the test. In the existing related instrument tests, the displacement of the anchor head and the deformation of the anchor are generally used to calculate the relative slippage between the anchor and the concrete, but the superposition of the errors in the measurement and calculation process will cause the error to become larger , and the method is more complicated; with the deepening of the research, it will also be used to install flexible parts at the contact position between the anchor rod and the concrete, and directly measure the deformation with a dial gauge, and because the rigidity of the flexible parts is small and the surface is smooth, it will also make the Inaccurate measurement results affect test results. In addition, due to the poor shear resistance of non-metallic materials, in the current test device, it is usually necessary to bond a steel sleeve to the outer wall of the non-metallic anchor for the pull-out test. The adhesive is generally epoxy resin and curing agent. On the one hand, in the process of injecting the binder, the binder leaks due to the lack of shelter in the lower part of the steel pipe, resulting in material waste; on the other hand, when the anchorage is welded on the outer wall of the steel casing, it will The adhesive was heated up, and the bond was not strong, resulting in insufficient bonding force between the steel casing and the anchor rod, resulting in the failure of the test. Therefore, it has very important practical significance and theoretical value to seek a new non-metallic anti-floating anchor rod and concrete relative slip test device to solve the shortcomings of the existing technology.

Invention content:

The purpose of the present invention is to overcome the shortcomings of the prior art, and seek to provide a method for testing the relative slippage of the non-metallic anti-floating anchor rod and the concrete interface, which is used to directly determine the relative slippage of the non-metallic anti-floating anchor rod and the concrete interface. It is convenient to study the anchoring performance of the bolt under load.

In order to achieve the above object, the present invention is realized in the non-metallic anti-floating anchor rod and the concrete interface relative sliding test device, and its specific test process is:

(1) Weld one side of the angle iron with the outer wall of the semicircular steel pipe to ensure that the angle iron and the semicircular steel pipe are firmly fixed together, and the unwelded side of the angle iron is perpendicular to the outer wall of the semicircular steel pipe;

(2) The semicircular steel pipe welded with angle iron is symmetrically bonded to the anchor rod body slightly higher than the surface of the reinforced concrete substrate with structural glue to ensure that the semicircular steel pipe is perpendicular to the surface of the reinforced concrete substrate;

(3) Insert a ring-shaped rubber plug into one end of the threaded steel casing, and install the threaded steel casing with the ring-shaped rubber plug on the anchor rod body so that the end with the ring-shaped rubber plug is located at the anchor rod body. The lower end, and then slowly inject structural glue through the upper end of the threaded steel casing to ensure that the structural glue is filled tightly, so that the threaded steel casing and the anchor rod body are tightly bonded together, and the length of the threaded steel pipe is controlled by the preset anchoring force;

(4) On the reinforced concrete base, place two I-beams symmetrically on both sides of the anchor body 1, ensuring that the distance between the two I-beams is 25-30cm, so that the anchor rod body is located between the two I-beams center, to ensure that the axis of the bolt is under tension;

(5) The through-center reaction beam passes through the anchor rod body and is placed on the I-beam to ensure that the centroid of the through-center reaction beam coincides with the anchor rod body;

(6) Install the steel backing plate, the through jack, the through-the-center steel plate and the load sensor on the through-the-center reaction beam from bottom to top to ensure that each part is upright and the centroid is coaxial with the anchor rod, so that the loading process The axis of the anchor rod body is under tension;

(7) Fix the threaded anchor on the threaded steel casing through the thread. The number of the anchor is determined by the preset pull-out force, so as to ensure that the anchor has sufficient locking force and prevent the threaded anchor from colliding with the thread when the load is applied. Steel casing produces shear failure;

(8) Install the dial indicator vertically on the fixed angle iron parallel to the ground, and fix the magnetic base of the dial indicator on the reference beam to ensure that it does not shake, and complete the non-metallic anti-floating anchor rod and concrete Installation of interface relative slip test device;

(9) Calibrate the through-hole jack and the load cell of the relative slippage test device between the non-metallic anti-floating anchor rod and the concrete interface to ensure the accuracy of the load applied at each level during the test;

(10) Test the relative slip between the non-metallic anti-floating anchor rod and the concrete interface, use a through-hole jack for loading, and control the rise of the through-hole jack to less than 10cm, and the reaction force of the through-hole jack acts on the through-hole reaction force The displacement of the anchor rod caused by the beam, at this time, the reading of the dial gauge is the relative slippage between the anchor rod and the concrete interface.

The main structure of the non-metallic anti-floating anchor rod and concrete interface relative slip test device according to the present invention includes an anchor rod body, a threaded steel casing, a threaded anchor, a load sensor, a piercing steel plate, a piercing jack, and a piercing steel pad Plate, center-through reaction beam, annular rubber stopper, I-beam, semicircular steel pipe, angle iron, dial indicator, magnetic table base, reference beam and reinforced concrete matrix; the anchor rod body of the fully threaded solid structure is reinforced by glass fiber Polymer (GFRP) to enhance the gripping force between the anchor rod body and the anchor body, which can provide sufficient anchoring friction; the inner wall of the threaded steel casing is smooth, and the outer wall is engraved with threads, and its inner diameter is larger than the diameter of the anchor rod body , the threaded steel casing and the anchor rod body are tightly bonded together by filling structural glue; the threaded anchor with hexagonal structure is made of a nut coupled with the threaded steel casing, and the threaded anchor is connected to the threaded steel sleeve through the thread The pipes are connected, and the number of threaded anchors is determined according to the required locking force; the inner diameter of the ring-shaped rubber plug is larger than the diameter of the anchor rod body, and the outer diameter is smaller than the inner diameter of the threaded steel casing, and the thickness of the ring-shaped rubber plug is 1.0cm , the anchor rod body passes through the ring-shaped rubber plug, which is installed at the bottom of the threaded steel pipe, which can not only block the structural glue, but also ensure that the anchor rod body is located in the center of the threaded steel casing, ensuring the surrounding of the anchor rod body The structural adhesive is filled evenly in the threaded steel casing and has sufficient cohesive force; the length of the semicircular steel pipe is 2cm, which is cut symmetrically from a steel pipe with the same diameter as the anchor rod, and the inner wall of the semicircular steel pipe is pasted on the anchor rod body by structural adhesive The outer side of the anchor rod body is symmetrically installed with I-beams on both sides. The I-beams are placed on the reinforced concrete matrix, and the bottom end of the anchor rod body is inserted into the reinforced concrete matrix; The center-through reaction beam of the rod body, the steel backing plate, the center-through jack, the center-through steel plate and the load sensor are installed vertically above the center-through reaction beam in sequence from bottom to top, the steel backing plate, the center-through jack, the center-through steel plate and the The load sensors pass through the anchor rod body; semicircular steel pipes are symmetrically pasted above the joint between the anchor rod body and the reinforced concrete matrix, one side of the angle iron is welded to the outer wall of the semicircular steel pipe, and the unwelded side is perpendicular to the outer wall of the semicircular steel pipe A dial indicator is installed directly above the angle iron, and a magnetic meter base is arranged on the dial indicator, and the magnetic meter base is fixed on the reference beam for measuring the relative slippage between the anchor rod body and the reinforced concrete matrix interface.

Compared with the existing test device, the present invention has simple process, high test precision, strong operability, direct numerical results, high precision and small error.

Description of drawings:

Fig. 1 is a schematic diagram of the main structure of the non-metallic anti-floating anchor rod and the concrete interface relative slip test device according to the present invention.

Fig. 2 is a schematic diagram of the A-A section structure principle of the non-metallic anti-floating anchor rod and the concrete interface relative slip test device according to the present invention.

Fig. 3 is a schematic diagram of the B-B section structure principle of the non-metallic anti-floating anchor rod and the concrete interface relative slip test device according to the present invention.

Fig. 4 is a schematic diagram of the installation structure principle of the dial indicator of the present invention.

Fig. 5 is a schematic cross-sectional view of the installation structure of the dial indicator of the present invention.

Detailed ways:

The present invention will be further described below through the embodiments and in conjunction with the accompanying drawings.

Example:

This embodiment is realized in the non-metallic anti-floating anchor rod and the concrete interface relative slippage test device, and the specific test process is as follows:

(1), one side of angle iron 12 is welded with the outer wall of semicircle steel pipe 11, guarantees that angle iron 12 and semicircle steel pipe 11 are tightly and firmly fixed together, and the unwelded surface of angle iron 12 is perpendicular to the outer wall of semicircle steel pipe 11;

(2), the semicircular steel pipe 11 welded with angle iron 12 is symmetrically bonded on the anchor rod body 1 slightly higher than the surface of the reinforced concrete substrate 16 with structural glue, ensuring that the semicircular steel pipe 11 is perpendicular to the surface of the reinforced concrete substrate 16;

(3), insert the ring-shaped rubber stopper 9 at one end of the threaded steel casing 2, and install the threaded steel casing 2 with the ring-shaped rubber stopper 9 on the anchor rod body 1, so that the ring-shaped rubber stopper 9 is installed One end is located at the lower end of the anchor rod body 1, and then the structural glue is slowly injected through the upper end of the threaded steel casing 2 to ensure that the structural glue is filled tightly, so that the threaded steel casing 2 and the bolt body 1 are tightly bonded together, the length of the threaded steel pipe Controlled by preset anchoring force;

(4), two I-beams 10 are symmetrically placed on both sides of the anchor rod body 1 on the reinforced concrete matrix 16, ensuring that the distance between the two I-beams 10 is 25-30cm, so that the anchor rod body 1 is located at the two sides. The center of the root I-beam ensures that the axis of the anchor rod is tensioned;

(5), the center-through reaction beam 8 passes through the anchor rod body 1 and is placed on the I-beam 10 to ensure that the centroid of the through-center reaction beam 8 coincides with the anchor rod body 1;

(6) Install the steel backing plate 7, the core jack 6, the core steel plate 5 and the load sensor 4 sequentially from bottom to top on the core-through reaction beam 8 to ensure that each component is upright and the centroid is coaxial with the anchor rod, The axis of the anchor rod body 1 is under tension during the loading process;

(7) Fix the threaded anchor 3 on the threaded steel casing 2 through threads. The number of anchors is determined by the preset pull-out resistance, so as to ensure that the anchor has sufficient locking force to prevent the threaded anchor from being locked when the load is applied. 3 and threaded steel casing 2 produce shear failure;

(8), vertically install the dial indicator 13 on the fixed angle iron 12 parallel to the ground, and the magnetic table base 14 of the dial indicator 13 is fixed on the reference beam 15 to ensure that it does not shake, and completes the non-metallic resistance. The installation of the relative sliding test device between the floating anchor rod and the concrete interface;

(9) Calibrate the through-hole jack 6 and the load cell 4 of the non-metallic anti-floating anchor rod and the concrete interface relative slippage test device to ensure the accuracy of the load applied at each level during the test;

(10), the non-metal anti-floating anchor rod and the concrete interface are tested for relative slippage, and the through-hole jack 6 is used for loading, and the rise of the through-hole jack 6 is controlled to be less than 10cm, and the reaction force of the through-hole jack 6 acts on the through-hole jack 6 The displacement of the anchor rod body 1 is caused by the central reaction beam 8, and the reading of the dial indicator 13 is the relative sliding amount of the anchor rod and the concrete interface.

The main structure of this embodiment includes a bolt body 1, a threaded steel casing 2, a threaded anchor 3, a load sensor 4, a piercing steel plate 5, a piercing jack 6, a piercing steel backing plate 7, and a piercing reaction beam 8 , ring-shaped rubber stopper 9, I-beam 10, semicircular steel pipe 11, angle iron 12, dial indicator 13, magnetic table base 14, reference beam 15 and reinforced concrete matrix 16; the anchor rod body 1 of the full-threaded solid structure is glass Fiber-reinforced polymer (GFRP), in order to enhance the gripping force between the anchor rod body 1 and the anchor body, can provide sufficient anchoring friction; the inner wall of the threaded steel casing 2 is smooth, and the outer wall is engraved with threads, and its inner diameter is larger than that of the anchor The diameter of the rod body 1, the threaded steel casing 2 and the anchor rod body 1 are tightly bonded together by filling structural glue; the hexagonal threaded anchor 3 is made of a nut coupled with the threaded steel casing 2, The threaded anchor 3 is connected with the threaded steel casing 2 through threads, and the number of threaded anchors 3 is determined according to the required locking force; the inner diameter of the annular rubber plug 9 is slightly larger than the diameter of the anchor rod body 1, and the outer diameter is slightly smaller than The inner diameter of the threaded steel casing 2 has a thickness of 1.0 cm. The anchor body 1 passes through the annular rubber stopper 9, which is installed at the bottom of the threaded steel pipe 2, which can not only block the structural glue, but also ensure that the anchor The rod body 1 is located in the center of the threaded steel casing 2 to ensure that the structural glue around the anchor rod body 1 is filled evenly in the threaded steel casing 2 and has sufficient cohesive force; Rod 1 is symmetrically cut from steel pipes with the same diameter, and the inner wall of semicircular steel pipe 11 is pasted on the outside of anchor rod body 1 by structural glue; On the reinforced concrete matrix 16, the bottom end of the anchor rod body 1 is inserted into the reinforced concrete matrix 16; two I-beams 10 are placed with a through-center reaction beam 8 passing through the anchor rod body 1, and a through-center reaction beam 8 The steel backing plate 7, the through-hole jack 6, the through-hole steel plate 5 and the load sensor 4 are installed vertically from bottom to top, and the steel backing plate 7, the through-hole jack 6, the through-hole steel plate 5 and the load sensor 4 all pass through the anchor Rod body 1; a semicircular steel pipe 11 is pasted symmetrically above the junction of the anchor rod body 1 and the reinforced concrete matrix 16, one side of the angle iron 12 is welded to the outer wall of the semicircular steel pipe 11, and the unwelded side is connected to the outer wall of the semicircular steel pipe 11 Vertical; a dial indicator 13 is installed directly above the angle iron 12, and the magnetic base 14 of the dial indicator 13 is fixed on the reference beam 15 for measuring the relative slip of the anchor rod body 1 and the reinforced concrete matrix 16 interface.

Claims (1)

1. a kind of nonmetallic anti-float anchor rod and concrete interface Relative sliding test method, it is characterised in that in nonmetallic anti-floating anchor Bar realizes that specific test process is with concrete interface Relative sliding test device：

(1), the side of angle bar and the outer wall of semicircle steel pipe are welded, it is ensured that angle bar and semicircle steel pipe close and firm it is fixed Together, the unwelded side of angle bar is vertical with semicircle outer wall of steel pipe；

(2), the effective structure glue symmetrical expression of the half rounds for being welded with angle bar is bonded in slightly above reinforced concrete body surface face On anchor rod body, it is ensured that semicircle steel pipe is vertical with reinforced concrete body surface face；

(3), cyclic annular rubber stopper is filled in screw-thread steel casing one end, the screw-thread steel casing for being plugged with cyclic annular rubber stopper is mounted on anchor pole On the body of rod, so that one end equipped with cyclic annular rubber stopper is located at the lower end of anchor rod body, then slowly noted by screw-thread steel sleeve upper end Enter structure glue, it is ensured that structure glue filling is closely knit, makes screw-thread steel casing together with anchor rod body tight bond, screw-thread steel casing Length is controlled by default anchor force；

(4), two I-steel are symmetrically disposed at anchor bar body both sides on armored concrete matrix, it is ensured that between two I-steel Distance be 25-30cm, so that anchor rod body is located at the center of two I-steel, guarantee anchor pole axial tension；

(5), punching reaction beam is placed in across anchor rod body on I-steel, it is ensured that the centre of form of punching reaction beam and anchor rod body weight It closes；

(6), installation punching billet, punching jack, punching steel plate and loading pass successively from down to up on punching reaction beam Sensor, it is ensured that each component is honest and the centre of form is coaxial with anchor pole, makes the axial tension of anchor rod body in its loading procedure；

(7), screw thread anchorage being threadedly secured on screw-thread steel casing, the number of anchorage is determined by default withdrawal resistance, to Ensure that anchor has enough coupling mechanism forces, screw thread anchorage generates failure by shear with screw-thread steel casing when preventing from being further applied load；

(8), the right angle setting dial gauge on the angle bar face parallel to the ground fixed is fixed on base on the Magnetic gauge stand of dial gauge On quasi- beam, ensure that it does not shake, completes the installation of nonmetallic anti-float anchor rod and concrete interface Relative sliding test device；

(9), to the punching jack and load sensor of nonmetallic anti-float anchor rod and concrete interface Relative sliding test device It is demarcated, the accuracy of the every grade of amount of being further applied load during guarantee test；

(10), nonmetallic anti-float anchor rod and concrete interface Relative sliding are tested, is loaded with punching jack, and The ascending amount for controlling punching jack is less than 10cm, and the counter-force of punching jack, which acts on punching reaction beam, causes anchor rod body Displacement, the reading of dial gauge is anchor pole and concrete interface relative slippage at this time；

The nonmetallic anti-float anchor rod and the agent structure of concrete interface Relative sliding test device include anchor rod body, screw thread Steel sleeve, screw thread anchorage, load sensor, punching steel plate, punching jack, punching billet, punching reaction beam, cyclic annular rubber Plug, I-steel, semicircle steel pipe, angle bar, dial gauge, Magnetic gauge stand, datum line beam and armored concrete matrix；Full thread solid construction Anchor rod body be made of glass fiber reinforced polymer material, to enhance the bond stress between anchor rod body and anchoring body, It is capable of providing enough anchoring frictional force；The inner wall smooth of screw-thread steel casing, outer wall are carved with screw thread, and internal diameter is more than anchor rod body Diameter, screw-thread steel casing and anchor rod body are in a manner of filling structure glue together with tight bond；The screw thread of hexagonal structure Anchorage is made of the nut being coupled with screw-thread steel casing, and screw thread anchorage is connected by screw thread with screw-thread steel casing, screw thread anchorage Number is determined according to required coupling mechanism force size；The internal diameter of cyclic annular rubber stopper is more than the diameter of anchor rod body, and outer diameter is less than screw-thread steel The thickness of the internal diameter of casing, cyclic annular rubber stopper is 1.0cm, and anchor rod body passes through cyclic annular rubber stopper, cyclic annular rubber stopper to be mounted on spiral shell The bottom end of line steel sleeve, can not only plugging structure glue, moreover it is possible to ensure that anchor rod body is located at the center of screw-thread steel casing, ensure anchor Structure glue around club shaft is filled uniformly in screw-thread steel casing, there is enough cohesive forces；The length of semicircle steel pipe is 2cm, It is symmetrically cut by the steel pipe with anchor pole same diameter, the inner wall of semicircle steel pipe is pasted onto the outer of anchor rod body by structure glue Side；The bilateral type of anchor rod body is equipped with I-steel, and I-steel is placed on armored concrete matrix, the bottom of anchor rod body End is inserted into reinforced concrete body；The punching reaction beam across anchor rod body, punching reaction beam are placed on two I-steel Top vertically-mounted punching billet, punching jack, punching steel plate and load sensor successively from bottom to top, punching steel pad Plate, punching jack, punching steel plate and load sensor both pass through anchor rod body；Anchor rod body joins with armored concrete matrix The top symmetrical expression at place is pasted with semicircle steel pipe, and the side of angle bar is welded with the outer wall of semicircle steel pipe, unwelded side and half The outer wall vertical of round steel pipe；Dial gauge is installed, dial gauge is equipped with Magnetic gauge stand, and Magnetic gauge stand is fixed on right over angle bar On datum line beam, the relative slippage for measuring anchor rod body and armored concrete basal body interface.