CN108717038B - A kind of concrete gas permeability resistance test device - Google Patents

Abstract

A device and a method for testing the gas permeation resistance of concrete. Relates to the field of concrete durability tests, in particular to a gas permeability test device and method for concrete. The concrete gas permeation resistance test device and method are simple in structure, convenient to process and capable of improving tightness and test reliability. Comprises a high-pressure gas cylinder, a gas permeation unit and a gas flowmeter; the gas permeation unit comprises a top plate, a bottom plate, a steel sleeve, a concrete test piece and an annular inflatable rubber capsule, wherein the steel sleeve is connected between the top plate and the bottom plate to form a test cavity, the concrete test piece and the inflatable rubber capsule are respectively positioned in the test cavity, and the concrete test piece and the PVC round pad are respectively positioned in the inflatable rubber capsule; the inside of the inflatable rubber capsule is provided with a test piece compensation mechanism, and the test piece compensation mechanism is used for wrapping a concrete test piece. According to the utility model, the test piece compensation mechanism is arranged, so that the sealing reliability of the concrete test piece is improved.

Description

A kind of concrete gas permeability resistance test device

Technical field

The invention relates to the field of concrete durability testing, and in particular to a gas permeability testing device and method for concrete.

Background technique

The decline in durability and premature deterioration of service performance of concrete materials are currently the most concerning issues in the scientific and engineering circles of cement concrete. Gas permeability is an important indicator of the durability of concrete. At present, mechanical sealing is usually used to test the gas permeability of concrete using the constant pressure method. In practice, it is found that this method has poor sealing effect and can easily cause damage to the concrete specimen, thereby affecting the authenticity and reliability of the experimental results of the concrete gas permeability coefficient.

As shown in Figure 5, when a high-pressure gas cylinder inflates an inflatable rubber bag, there is a convex effect in the middle of the inflated rubber bag, which causes the concrete specimen to be stressed and easily damaged. At the same time, both ends are concave, which reduces the sealing ability. reliability.

Contents of the invention

In view of the above problems, the present invention provides a concrete gas permeability resistance testing device and method that has a simple structure, is convenient for processing, and improves sealing performance and test reliability.

The technical solution of the present invention is to include a high-pressure gas cylinder, a gas permeation unit and a gas flow meter; the gas permeation unit includes a top plate, a bottom plate, a steel sleeve, a concrete specimen and an annular inflatable rubber bag, and the steel sleeve is connected to the top plate and A test chamber is formed between the bottom plates. The concrete specimen and the inflatable rubber bag are respectively located in the test chamber. A PVC circular backing plate is provided between the concrete specimen and the top plate. A PVC circular pad is provided between the concrete specimen and the bottom plate. Backing plate two, the concrete specimen and PVC round backing plates one and two are located in the inflatable rubber bag;

The steel sleeve is provided with an air inlet connected to the inflatable rubber airbag, and the air inlet is connected to the high-pressure gas cylinder through a trachea.

The bottom plate and the second PVC circular backing plate are provided with a permeation unit air inlet, the top plate and the first PVC circular backing plate are provided with a permeation unit air outlet, and the permeation unit air inlet is connected to the high-pressure gas cylinder through a trachea, so The gas outlet of the permeation unit is connected to the gas flow meter through the trachea;

A specimen compensation mechanism is provided on the inside of the inflatable rubber bag, and the specimen compensation mechanism is used to wrap the concrete specimen.

The specimen compensation mechanism includes an annular sleeve, an air path is provided inside the sleeve, an annular air bag is provided on the middle outer side of the sleeve that communicates with the air path, and the bottom plate is provided with an air hole that communicates with the air path. The stomata are connected to the high-pressure gas cylinder through the trachea;

The sleeve is used to wrap the concrete specimen and PVC circular backing plates one and two.

Two annular air bags are respectively provided on the inner sides of both ends of the sleeve. The first and second PVC circular pads are respectively provided with annular inlay grooves. The two air bags are connected to the air path and the two air bags are adapted to each other. The ground is set in the groove.

The specimen compensation mechanism is: a flexible baffle ring is provided on the bottom surface of the PVC circular backing plate one, a flexible baffle ring two is provided on the top surface of the PVC circular backing plate two, the flexible baffle ring one and the flexible baffle ring are provided on the top surface of the PVC circular backing plate two. The two rings are both in the shape of a frustum and are arranged symmetrically. The flexible baffle ring one contacts the flexible baffle ring two, so that a sealed cavity is formed between the PVC circular backing plate one and the PVC circular backing plate two. The concrete specimen is located in the sealed cavity. Inside.

A sealing ring is provided between the end surfaces of the first flexible baffle ring and the second flexible baffle ring.

The specimen compensation mechanism includes a cylinder, which is used to wrap the concrete specimen and PVC circular backing plates one and two. There is an annular flexible protrusion in the middle of the cylinder, and there is an annular flexible protrusion inside the flexible protrusion. spring.

When the invention is working, a closed test cavity is formed by the top plate, the steel sleeve and the bottom plate, and the concrete specimen is placed in the test cavity. One and two PVC circular pads are respectively placed above and below the concrete specimen to wrap it up. In the inflatable rubber bag, first, the inflatable rubber bag is inflated through a high-pressure gas cylinder to achieve sealing;

Then, the high-pressure gas cylinder takes in air through the air inlet of the permeation unit on the bottom plate and PVC circular backing plate two, and then discharges air through the permeation unit air outlet on the top plate and PVC circular backing plate one, and is tested through a gas flow meter;

By setting up a specimen compensation mechanism, damage to the concrete specimen is avoided, and at the same time, the sealing performance of the test is improved.

The concrete specimen in the present invention is in the shape of a round cake, with one and two PVC round backing plates provided on the upper and lower sides respectively. By arranging a specimen compensation mechanism, the sealing reliability of the concrete specimen is improved.

Description of drawings

Figure 1 is a working state diagram of the present invention,

Figure 2 is a schematic structural diagram of Embodiment 1 of the specimen compensation mechanism.

Figure 3 is a schematic structural diagram of the second embodiment of the specimen compensation mechanism.

Figure 4 is a schematic structural diagram of Embodiment 3 of the specimen compensation mechanism.

Figure 5 is a schematic structural diagram of the prior art;

1 in the picture is a high-pressure gas cylinder.

2 is the gas permeation unit, 21 is the top plate, 22 is the bottom plate, 23 is the steel sleeve, 230 is the air inlet, 24 is the concrete specimen, 25 is the inflatable rubber bag, 26 is the PVC round pad, 27 is the PVC round pad On the second plate, 28 is the air inlet of the permeation unit, and 29 is the air outlet of the permeation unit.

3 is the gas flow meter,

4 is the specimen compensation mechanism,

41 is the sleeve, 411 is the air path, 412 is the air bag one, 413 is the air hole, 414 is the air bag two, 415 is the embedding groove,

421 is the flexible baffle ring one, 422 is the flexible baffle ring two, and 423 is the sealing ring.

43 is a cylinder, 431 is a flexible protrusion, 432 is a spring,

5 is the gas circuit switch, 6 is the pressure reducing valve;

The arrow in Figure 5 represents the state of the inflated rubber bag after it is inflated.

Detailed ways

As shown in Figures 1-4, the present invention includes a high-pressure gas cylinder 1, a gas permeation unit 2 and a gas flow meter 3; the gas permeation unit includes a top plate 21, a bottom plate 22, a steel sleeve 23, a concrete specimen 24 and annular inflatable rubber. Bag 25, the steel sleeve is connected between the top plate and the bottom plate to form a test chamber, the concrete specimen and the inflatable rubber bag are respectively located in the test chamber, and a PVC round pad is provided between the concrete specimen and the top plate. There is a PVC round backing plate two between the concrete specimen and the bottom plate. The concrete specimen and the PVC round backing plates one and two are located in the inflatable rubber bag (so that the inflatable rubber bag wraps the concrete specimen and the upper and lower PVC round backing plates. );

The steel sleeve is provided with an air inlet 230 connected to the inflatable rubber airbag, and the air inlet is connected to the high-pressure gas cylinder through a trachea.

The bottom plate and the PVC circular backing plate are provided with a permeation unit air inlet 28. The top plate and the PVC circular backing plate are provided with a permeation unit air outlet 29. The permeation unit air inlet is connected to the high-pressure gas cylinder through a trachea. , the gas outlet of the permeation unit is connected to the gas flow meter through the trachea; during operation, a gas path switch 5 is provided on the trachea to facilitate opening and closing control, and a pressure reducing valve 6 is provided to facilitate control of gas pressure.

A specimen compensation mechanism 4 is provided on the inside of the inflatable rubber bag, and the specimen compensation mechanism is used to wrap the concrete specimen.

When the invention is working, a closed test cavity is formed by the top plate, the steel sleeve and the bottom plate, and the concrete specimen is placed in the test cavity. One and two PVC circular pads are respectively placed above and below the concrete specimen to wrap it up. In the inflatable rubber bag, first, the inflatable rubber bag is inflated through a high-pressure gas cylinder to achieve sealing;

Then, the high-pressure gas cylinder takes in air through the air inlet of the permeation unit on the bottom plate and PVC circular backing plate two, and then discharges air through the permeation unit air outlet on the top plate and PVC circular backing plate one, and is tested through a gas flow meter;

By setting up a specimen compensation mechanism, damage to the concrete specimen is avoided, and at the same time, the sealing performance of the test is improved.

The concrete specimen in the utility model is in the shape of a round cake, with one and two PVC round backing plates provided on the upper and lower sides respectively. By setting up a specimen compensation mechanism, the sealing reliability of the concrete specimen is improved.

The specimen compensation mechanism includes an annular sleeve 41, an air path 411 is provided inside the sleeve, an annular air bag 412 connected to the air path is provided on the middle outside of the sleeve, and a connected air path is provided on the bottom plate. The stomata 413 are connected to the high-pressure gas cylinder through the trachea;

The sleeve is used to wrap the concrete specimen and PVC circular backing plates one and two.

By setting the sleeve, the high-pressure gas bottle inflates the air bag on the sleeve so that it acts on the middle of the inflatable rubber bag. In this way, the middle of the inflatable rubber bag is concave to avoid damage to the concrete specimen; both ends are outward The bulge allows it to reliably contact the PVC round gaskets one and two through the sleeve to improve the sealing performance.

Two annular air bags 414 are respectively provided on the inner sides of both ends of the sleeve. The first and second PVC circular backing plates are respectively provided with annular inlay grooves 415. The second air bag is connected to the air path, and the second air bag is connected to the air path. Adaptably located in the embedding groove.

By arranging the cooperation between the second air bag and the embedding groove, on the one hand, the positioning is reliable; on the other hand, the sealing between the sleeve and the PVC circular backing plates one and two is better, ensuring the reliability of concrete specimen testing.

The specimen compensation mechanism is: the bottom surface of the PVC circular backing plate is provided with a flexible baffle ring 421, the top surface of the PVC circular backing plate two is provided with a flexible baffle ring 422, the flexible baffle ring one and The two flexible baffle rings are both in the shape of a frustum and are arranged symmetrically. The first flexible baffle ring contacts the second flexible baffle ring, so that a sealed cavity is formed between the PVC circular backing plate one and the PVC circular backing plate two. The concrete specimen is located inside the sealed cavity.

The structure of the flexible ring plate one and the flexible baffle ring two is the same. By arranging the two to contact, a sealing cavity is formed. On the one hand, the sealing performance is improved; on the other hand, the inflatable rubber bag is used to squeeze the flexible baffle rings one and two after being inflated. , to avoid damaging the concrete specimen, and at the same time, further ensure the sealing performance of the sealing cavity. The first and second flexible retaining rings can be rubber rings to facilitate processing.

A sealing ring 423 is provided between the end surfaces of the flexible baffle ring one and the flexible baffle ring two.

By setting the sealing ring, the sealing performance is ensured and the reliability of the test is improved.

The specimen compensation mechanism includes a cylinder 43, which is used to wrap the concrete specimen and PVC circular backing plates one and two. An annular flexible protrusion 431 is provided in the middle of the cylinder, and the inner part of the flexible protrusion is A spring 432 is provided.

During work, after the inflatable rubber bag is inflated, its middle directly acts on the flexible bulge. In this way, the spring forms an indentation in the middle to avoid damage to the concrete specimen; both ends bulge outward to make it pass through the sleeve reliably. Contact PVC round gaskets one and two to improve sealing. Flexible bumps, such as rubber bumps, can be used to place springs.

The invention is specifically divided into a test gas circuit system and a sealed gas circuit system. The high-pressure gas cylinder is connected to the air inlet of the permeability unit through a trachea, and passes through the concrete specimen. The pressure regulating valve (such as pressure reducing valve 6) accurately controls the pressure value of the gas circuit system. The gas in the test gas circuit system penetrates through the concrete specimen under a certain pressure. The inflatable rubber airbag expands under a certain gas pressure. At the same time, the specimen compensation mechanism is set to completely wrap the concrete specimen to avoid damage to the concrete specimen. At the same time, it prevents the gas in the test air path from overflowing from the side, thereby achieving excellent sealing effect. and steady-state gas penetration process to improve the authenticity and reliability of test results.

Claims (1)

1. A concrete anti-gas permeability test device comprises a high-pressure gas cylinder, a gas permeation unit and a gas flowmeter; the gas permeation unit is characterized by comprising a top plate, a bottom plate, a steel sleeve, a concrete test piece and an annular inflatable rubber bag, wherein the steel sleeve is connected between the top plate and the bottom plate to form a test cavity;

the steel sleeve is provided with an air inlet communicated with the inflatable rubber air bag, the air inlet is communicated with the high-pressure air bottle through an air pipe,

the bottom plate and the second PVC round pad plate are provided with a permeation unit air inlet, the top plate and the first PVC round pad plate are provided with a permeation unit air outlet, the permeation unit air inlet is communicated with the high-pressure air bottle through an air pipe, and the permeation unit air outlet is communicated with the air flowmeter through the air pipe;

the inner side of the inflatable rubber capsule is provided with a test piece compensation mechanism, and the test piece compensation mechanism is used for wrapping a concrete test piece;

the test piece compensation mechanism comprises an annular sleeve, an air passage is arranged in the sleeve, an annular air bag I communicated with the air passage is arranged on the outer side of the middle of the sleeve, an air hole communicated with the air passage is formed in the bottom plate, and the air hole is communicated with the high-pressure air bottle through an air pipe;

the sleeve is used for wrapping the concrete test piece and the first and second PVC round backing plates;

annular air bags II are respectively arranged on the inner sides of two ends of the sleeve, annular caulking grooves are respectively formed in the first PVC round pad plate and the second PVC round pad plate, the air bags II are communicated with the air passage, and the air bags II are adaptively arranged in the caulking grooves.