CN113588472A - Device for measuring diffusion flux of concrete annular gas under continuous load action - Google Patents
Device for measuring diffusion flux of concrete annular gas under continuous load action Download PDFInfo
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- 239000004567 concrete Substances 0.000 title claims abstract description 73
- 238000009792 diffusion process Methods 0.000 title claims abstract description 45
- 230000004907 flux Effects 0.000 title claims abstract description 16
- 230000009471 action Effects 0.000 title abstract description 9
- 238000012360 testing method Methods 0.000 claims abstract description 51
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 claims abstract description 46
- 230000000694 effects Effects 0.000 claims description 5
- 229920006335 epoxy glue Polymers 0.000 claims description 4
- 239000007789 gas Substances 0.000 abstract description 28
- 238000000034 method Methods 0.000 abstract description 5
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 46
- 239000001301 oxygen Substances 0.000 description 46
- 229910052760 oxygen Inorganic materials 0.000 description 46
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 14
- 230000007797 corrosion Effects 0.000 description 8
- 238000005260 corrosion Methods 0.000 description 8
- 238000007789 sealing Methods 0.000 description 8
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 7
- 229910052757 nitrogen Inorganic materials 0.000 description 7
- 239000000741 silica gel Substances 0.000 description 7
- 229910002027 silica gel Inorganic materials 0.000 description 7
- 229910000831 Steel Inorganic materials 0.000 description 5
- 108010025899 gelatin film Proteins 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 239000010959 steel Substances 0.000 description 5
- 206010021143 Hypoxia Diseases 0.000 description 3
- 229910001294 Reinforcing steel Inorganic materials 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 230000007954 hypoxia Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
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- 150000001875 compounds Chemical class 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000001146 hypoxic effect Effects 0.000 description 1
- 210000003141 lower extremity Anatomy 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000011150 reinforced concrete Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
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- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/56—Investigating resistance to wear or abrasion
- G01N3/567—Investigating resistance to wear or abrasion by submitting the specimen to the action of a fluid or of a fluidised material, e.g. cavitation, jet abrasion
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
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- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/08—Investigating permeability, pore-volume, or surface area of porous materials
- G01N15/0806—Details, e.g. sample holders, mounting samples for testing
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/08—Investigating permeability, pore-volume, or surface area of porous materials
- G01N15/082—Investigating permeability by forcing a fluid through a sample
- G01N15/0826—Investigating permeability by forcing a fluid through a sample and measuring fluid flow rate, i.e. permeation rate or pressure change
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Abstract
The invention discloses a device for measuring diffusion flux of concrete in an annular direction to gas under the action of continuous load, which comprises an annular concrete test block, a lower loading plate, an upper loading plate, an annular acrylic inner sleeve, an annular acrylic outer sleeve, a first closed chamber and a second closed chamber, wherein the lower loading plate, the upper loading plate, the annular acrylic inner sleeve, the annular acrylic outer sleeve, the first closed chamber and the second closed chamber are horizontally arranged; the upper loading plate is provided with one or more air inlet holes, one or more air outlet holes and one or more concentration sensor mounting holes, the one or more air outlet holes are communicated with the first closed chamber and/or the second closed chamber, the concentration sensor is mounted in the concentration sensor mounting holes and is connected with a data recorder, the air inlet holes are connected with an external gas bottle, and the air outlet holes are provided with valves. Compared with the prior art, the method can measure the diffusion rate of harmful gases around the annular concrete test block into the annular concrete test block, can apply continuous pressure load, and is more suitable for the actual engineering situation.
Description
Technical Field
The invention relates to the field of concrete durability testing, in particular to a device for measuring the diffusion flux of concrete circular gas under the action of continuous load.
Background
The corrosion of steel bars in a reinforced concrete structure is one of the important factors for the damage of concrete results, and the oxygen concentration, the chloride ion concentration and the saturation degree of the concrete influence the corrosion rate of the steel bars. In an actual engineering structure, oxygen is used as an oxidant for reinforcing steel bar corrosion, and along with the increase of the diffusion rate of the oxygen, the reinforcing steel bar corrosion rate is increased.
At present, the research on the corrosion of the steel bars is mainly carried out from the aspects of chloride ion concentration, saturation, oxygen content and the like, the research on the oxygen concentration and the corrosion of the steel bars is less, and the influence of oxygen on the corrosion of the steel bars is mainly researched by measuring the oxygen diffusion coefficient. The existing test device measures all the unidirectional oxygen diffusion coefficients, the concrete members in the actual engineering environment basically contact with air all around, and gas diffuses from all around to the interior of the concrete.
Concrete is a porous heterogeneous material, wherein the gas diffusion law follows Fick's diffusion law, namely the diffusion driving force of gas is only concentration gradient, and the diffusion effect occurs. Only the unidirectional gas diffusion study in concrete has certain one-sidedness. Therefore, a device for measuring the diffusion flux of the concrete in the circumferential direction to the gas under the load action is designed to be closer to the actual design, and a foundation is laid for the subsequent calculation of the gas diffusion coefficient and the research of the influence of the gas diffusion on the corrosion of the reinforcing steel bars.
The existing test device is complex to assemble, and can only measure the gas diffusion coefficient after unidirectional diffusion. For example, the Chinese patent No. CN201710485141.0, entitled "concrete oxygen diffusion coefficient testing device" with the publication date of 12/05/2020, discloses a device for measuring oxygen diffusion coefficient; the Chinese patent No. CN204944930U, granted on 2016, 01/06/h, entitled "A concrete member load-bearing loading frame under tension", discloses a device for arranging continuous tension load on a concrete sample. Whether the concrete is stressed and the thickness of the concrete have an important influence on the oxygen diffusion coefficient. In practical situations, concrete is loaded, harmful gases are diffused into the concrete from the periphery, and the gas diffusion effect of the concrete is significantly influenced under the load effect. Therefore, it is imperative to design a device for measuring the diffusion coefficient of the concrete to the gas in the circumferential direction under the action of continuous load.
Disclosure of Invention
The invention aims to solve the defects in the prior art and provides a device for measuring the diffusion flux of the concrete annular gas under the action of continuous load.
In order to achieve the purpose, the invention is implemented according to the following technical scheme:
the utility model provides a survey device that concrete ring under continuous load effect diffuses flux to gas, includes annular concrete test block, still includes:
the device comprises a lower loading plate and an upper loading plate, wherein the lower loading plate is horizontally arranged, the upper loading plate is arranged above the lower loading plate and is parallel to the lower loading plate, an annular acrylic inner sleeve is fixed on the upper end surface of the lower loading plate, an annular acrylic outer sleeve is fixed on the lower end surface of the upper loading plate, the annular acrylic outer sleeve is used for being sleeved outside the annular acrylic inner sleeve, the inner diameter of the annular acrylic outer sleeve is the same as the outer diameter of the annular acrylic inner sleeve, and the upper loading plate is detachably connected with the lower loading plate; a first closed chamber is formed in a sealed cylindrical space region between the inner surface of the annular concrete test block and the upper and lower loading plates, a second closed chamber is formed between the lower end surface of the upper loading plate and the outer surface of the annular concrete test block, and between the upper end surfaces of the annular acrylic outer sleeve, the annular acrylic inner sleeve and the lower loading plate and between the upper end surface of the annular concrete test block and the outer surface of the annular concrete test block, and the upper and lower ends of the annular concrete test block are fixed through the upper loading plate and the lower loading plate;
the upper loading plate is provided with one or more air inlet holes, one or more air outlet holes and one or more concentration sensor mounting holes, the one or more air outlet holes are communicated with the first closed chamber and/or the second closed chamber, the concentration sensor is mounted in the concentration sensor mounting holes and is connected with a data recorder, the air inlet holes are connected with an external gas bottle, and the air outlet holes are provided with valves.
Furthermore, the number of the air inlet holes, the number of the air outlet holes and the number of the concentration sensor mounting holes are respectively two, wherein one air inlet hole, one air outlet hole and one concentration sensor mounting hole form a first group; the other air inlet hole, the air outlet hole and the concentration sensor mounting hole form a second group; the air inlet holes, the air outlet holes and the concentration sensor mounting holes of the first group are annularly and uniformly distributed on the upper loading plate above the first closed chamber, and the air inlet holes, the air outlet holes and the concentration sensor mounting holes of the second group are annularly and uniformly distributed on the upper loading plate above the second closed chamber.
Further, the height of annular ya keli outer sleeve and annular ya keli inner sleeve all sets up to two-thirds of the height of annular concrete test block.
Furthermore, the lower end face of the upper loading plate and the upper end face of the lower loading plate are respectively provided with an annular groove, the top end of the annular concrete test block is embedded into the annular groove on the upper loading plate, and the tail end of the annular concrete test block is embedded into the annular groove on the lower loading plate.
Furthermore, the upper loading plate and the lower loading plate are connected through bolts and nuts, a plurality of bolts are vertically fixed on the edge of the upper end face of the lower loading plate in an annular shape, and the top ends of the bolts penetrate through bolt holes formed in the upper loading plate and are locked through the nuts.
Furthermore, in order to ensure the sealing performance of a closed cavity formed between the lower end surface of the upper loading plate and the upper end surfaces of the annular acrylic outer sleeve, the annular acrylic inner sleeve and the lower loading plate, epoxy glue is coated on the overlapped joint of the annular acrylic outer sleeve and the annular acrylic inner sleeve.
Compared with the prior art, the invention has the following beneficial effects:
the method can measure the rate of harmful gas around the annular concrete test block diffusing into the annular concrete test block, and can apply continuous pressure load to better fit the actual engineering situation;
according to the invention, the silica gel films are arranged on the air outlet holes of the two chambers, and due to the changeability of the silica gel films, the balance between the air pressure in the air chamber and the atmospheric pressure can be ensured, and the diffusion driving force is ensured to be only the concentration gradient;
the pressurizing and gas diffusion device is integrated, the device is light, convenient and fast to operate, simple to combine, good in sealing performance and small in test error.
Drawings
FIG. 1 is a schematic structural diagram of the present invention.
Fig. 2 is a schematic structural view of an upper loading plate according to the present invention.
Fig. 3 is a schematic structural view of a lower loading plate according to the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. The specific embodiments described herein are merely illustrative of the invention and do not limit the invention.
As shown in fig. 1 to fig. 3, this embodiment specifically discloses a device for measuring the diffusion flux of the concrete annular gas under the action of a continuous load, which includes an annular concrete test block, and further includes:
the device comprises a lower loading plate 1 and an upper loading plate 3, wherein the lower loading plate 1 is horizontally arranged, the upper loading plate 3 is arranged above the lower loading plate 1 and is parallel to the lower loading plate 1, an annular acrylic inner sleeve 12 is fixed on the upper end surface of the lower loading plate 1, an annular acrylic outer sleeve 5 is fixed on the lower end surface of the upper loading plate 3, the annular acrylic outer sleeve 5 is used for being sleeved outside the annular acrylic inner sleeve 12, the inner diameter of the annular acrylic outer sleeve 5 is the same as the outer diameter of the annular acrylic inner sleeve 12, the upper loading plate 3 is detachably connected with the lower loading plate 1, specifically, as shown in figure 1, the upper loading plate 3 is connected with the lower loading plate 1 through bolts 2 and nuts 4, four bolts 2 are vertically fixed on the edge of the upper end surface of the lower loading plate 1 in an annular manner, the top ends of the bolts 2 penetrate through bolt holes 14 formed in the upper loading plate 3 and then are locked through the nuts 4, and in the assembling process, the force for screwing the nut 4 can be determined according to the size of the load needing to be loaded; a first closed chamber is formed in a sealed cylindrical space region between the inner surface of the annular concrete test block and the upper and lower loading plates 3 and 1, a second closed chamber is formed between the lower end surface of the upper loading plate 3 and the outer surface of the annular concrete test block and between the upper end surface of the annular acrylic outer sleeve 5, the annular acrylic inner sleeve 12 and the lower loading plate 1 and the outer surface of the annular concrete test block, and the upper and lower ends of the annular concrete test block are fixed by the upper and lower loading plates 3 and 1.
The upper loading plate 3 is provided with two air inlet holes, two air outlet holes and two concentration sensor mounting holes which are respectively marked as a first air inlet hole 9, a second air inlet hole 8, a first air outlet hole 10, a second air outlet hole 7, a first concentration sensor mounting hole 11 and a second concentration sensor mounting hole 6, wherein the first air inlet hole 9, the first air outlet hole 10 and the first concentration sensor mounting hole 11 are annularly and uniformly distributed on the upper loading plate 3 above the first closed cavity, and the second air inlet hole 8, the second air outlet hole 7 and the second concentration sensor mounting hole 6 are annularly and uniformly distributed on the upper loading plate 3 above the second closed cavity; oxygen concentration sensors are respectively arranged in the first concentration sensor mounting hole 11 and the second concentration sensor mounting hole 6 and are connected with a data recorder, the first air inlet hole 9 is connected with an external nitrogen cylinder and is used for injecting nitrogen into the first closed cavity, and the second air inlet hole 8 is connected with an external oxygen cylinder and is used for injecting oxygen into the second closed cavity; the first air outlet hole 10 and the second air outlet hole 7 are provided with valves, and in the actual use process, the first air outlet hole 10 and the second air outlet hole 7 are used for discharging redundant gas. Then, the valves of the first air outlet hole 10 and the second air outlet hole 7 are closed, the silica gel film is sleeved on the first air outlet hole 10 and the second air outlet hole 7, then the valves of the first air outlet hole 10 and the second air outlet hole 7 are opened, and then the test gas is filled from the air inlet hole. The purpose of sleeving the silica gel film is to ensure that the pressure inside and outside the gas chamber is the same by utilizing the changeability of the silica gel film.
In this embodiment, the heights of the annular acrylic outer sleeve 5 and the annular acrylic inner sleeve 12 are both set to be two thirds of the height of the annular concrete test block. During loading, two thirds of coincidence between annular ya keli outer sleeve 5 and the annular ya keli inner skleeve 12, the lower limb of annular ya keli outer sleeve 5 can not contact lower loading plate 1 during loading promptly, can guarantee like this that annular ya keli outer sleeve 5 and annular ya keli inner skleeve 12 need not the atress when applying load, guarantee that first airtight cavity and second cavity interior volume and pressure are unchangeable all the time.
In the actual use process, in order to fix the annular concrete test block between the upper loading plate 3 and the lower loading plate 1 without displacement, the lower end face of the upper loading plate 3 and the upper end face of the lower loading plate 1 are respectively provided with an annular groove 13, the top end of the annular concrete test block is embedded into the annular groove 13 on the upper loading plate 3, and the tail end of the annular concrete test block is embedded into the annular groove 13 on the lower loading plate 1, however, in order to better ensure the sealing property, the top of the outer ring of the annular groove 13 can be firstly placed into a sealing gasket, and then the annular concrete test block is embedded into the annular groove 13.
After the annular acrylic outer sleeve 5 is sleeved on the annular acrylic inner sleeve 12, in order to ensure the sealing performance of a closed cavity formed between the lower end surface of the upper loading plate 3 and the upper end surfaces of the annular acrylic outer sleeve 5, the annular acrylic inner sleeve 12 and the lower loading plate 1, epoxy glue is coated on the overlapped seam of the annular acrylic outer sleeve 5 and the annular acrylic inner sleeve 12.
When the device for measuring the gas diffusion flux in the concrete ring direction under the continuous load action in the embodiment is used for measuring the gas diffusion flux in the concrete ring direction, the following specific operations are performed (the operation is the prior art):
utilizing a mould to pour the annular concrete test block, maintaining for 28d, and smearing epoxy resin on the non-diffusion surface of the annular concrete test block after the maintenance is finished to ensure the air tightness;
placing a lower loading plate on a plane, placing a sealing washer at the top of the outer ring of an annular groove of the lower loading plate, placing an upper annular concrete test block, covering an upper loading plate with the sealing washer, sleeving an annular acrylic outer sleeve on the annular acrylic inner sleeve, gradually screwing four nuts to ensure that the upper loading plate and the lower loading plate are parallel, determining the force for screwing the nuts according to the load required, and smearing epoxy glue at the superposed joint of the annular acrylic inner sleeve and the annular acrylic outer sleeve after the nut is screwed, so as to further ensure the sealing performance of a first sealed chamber and a second chamber;
a nitrogen cylinder and an oxygen concentration sensor are sequentially connected in an air inlet hole and a concentration sensor mounting hole above the first closed cavity, the oxygen concentration sensor is connected to a data recorder, a valve is arranged at an air outlet, the nitrogen cylinder is opened, then nitrogen is slowly filled into the nitrogen cylinder, then the valve of the air outlet is rapidly closed, then a silica gel film is arranged on the valve, and then the valve is opened; an oxygen cylinder and an oxygen concentration sensor are sequentially connected in an air inlet hole and an oxygen concentration sensor mounting hole above the second closed cavity, the oxygen concentration sensor is connected to a data recorder (the two oxygen concentration sensors can share one data recorder), a valve is arranged at the air outlet, the valve of the air outlet is rapidly closed after the oxygen cylinder is opened and nitrogen is slowly filled, a silica gel film is then arranged on the valve, and the valve is opened.
Waiting for the test, performing data processing and result analysis according to data recorded by a data recorder after the test is finished, opening a calibrated oxygen data recorder connected with the two closed chambers, recording the time t as 0, recording the oxygen concentration in the two closed chambers at the time by using the data recorder, and transmitting the oxygen concentration to a computer; according to the data, due to the oxygen concentration difference of the two chambers, oxygen diffuses in the annular concrete test block under the power of the oxygen concentration gradient, and the oxygen diffusion coefficient of the annular concrete test block is obtained according to the following formula:
wherein N is the amount (mol) of the substance of total oxygen that increases from the time when the hypoxia chamber t is 0 to the end of the test; dAEquivalent oxygen diffusion coefficient; s is the effective diffusion area; t is the experimental time;
is the concentration gradient of oxygen in the x-direction.
According to Fick's first law, and under the test method, assuming that the diffusion mode of oxygen is one-dimensional diffusion, there are
Where N is the amount of species (mol) of total oxygen that increases from the time the hypoxic chamber t is 0 to the end of the experiment, DA is the equivalent oxygen diffusivity,
the concentration gradient of oxygen in the x direction, S the effective diffusion area, and t the experimental time.
The equivalent oxygen diffusion coefficient obtained from the above formula is
According to the oxygen percentage content and the chamber volume recorded by the two closed chambers at different moments, and by combining an ideal gas state equation, the oxygen concentration values of the two chambers at different moments can be obtained, and assuming that the oxygen concentration is linearly distributed in the concrete material and the oxygen is diffused into one-dimensional diffusion, the oxygen concentration values can be obtained:
in the formula: c2The oxygen concentration (mol/m) in the high oxygen chamber at a certain moment3)，C1Is hypoxia at the same timeOxygen concentration value in the chamber (mo 1/m)3) And X is the thickness (m) of the cement-based material test piece. According to the formula, the compound has the advantages of,
is a function related to time, and the oxygen concentration gradients of the left cavity and the right cavity of the concrete material test piece at different times are different. And the function with time can be obtained by fitting data according to data recorded in the test by using originPro software, so that the oxygen diffusion coefficient of the tested concrete material test piece can be obtained by calculation according to the formula.
The technical solution of the present invention is not limited to the limitations of the above specific embodiments, and all technical modifications made according to the technical solution of the present invention fall within the protection scope of the present invention.
Claims (6)
1. The utility model provides a survey device of concrete ring under continuous load effect to gas diffusion flux, includes annular concrete test block, its characterized in that still includes:
the device comprises a lower loading plate and an upper loading plate, wherein the lower loading plate is horizontally arranged, the upper loading plate is arranged above the lower loading plate and is parallel to the lower loading plate, an annular acrylic inner sleeve is fixed on the upper end surface of the lower loading plate, an annular acrylic outer sleeve is fixed on the lower end surface of the upper loading plate, the annular acrylic outer sleeve is used for being sleeved outside the annular acrylic inner sleeve, the inner diameter of the annular acrylic outer sleeve is the same as the outer diameter of the annular acrylic inner sleeve, and the upper loading plate is detachably connected with the lower loading plate; a first closed chamber is formed in a sealed cylindrical space region between the inner surface of the annular concrete test block and the upper and lower loading plates, a second closed chamber is formed between the lower end surface of the upper loading plate and the outer surface of the annular concrete test block, and between the upper end surfaces of the annular acrylic outer sleeve, the annular acrylic inner sleeve and the lower loading plate and between the upper end surface of the annular concrete test block and the outer surface of the annular concrete test block, and the upper and lower ends of the annular concrete test block are fixed through the upper loading plate and the lower loading plate;
the upper loading plate is provided with one or more air inlet holes, one or more air outlet holes and one or more concentration sensor mounting holes, the one or more air outlet holes are communicated with the first closed chamber and/or the second closed chamber, the concentration sensor is mounted in the concentration sensor mounting holes and is connected with a data recorder, the air inlet holes are connected with an external gas bottle, and the air outlet holes are provided with valves.
2. The apparatus for measuring the diffusion flux of concrete into gas under continuous load according to claim 1, wherein: the air inlet hole, the air outlet hole and the concentration sensor mounting hole are respectively arranged in two, wherein one air inlet hole, one air outlet hole and one concentration sensor mounting hole form a first group; the other air inlet hole, the air outlet hole and the concentration sensor mounting hole form a second group; the air inlet holes, the air outlet holes and the concentration sensor mounting holes of the first group are annularly and uniformly distributed on the upper loading plate above the first closed chamber, and the air inlet holes, the air outlet holes and the concentration sensor mounting holes of the second group are annularly and uniformly distributed on the upper loading plate above the second closed chamber.
3. The apparatus for measuring the diffusion flux of concrete into gas under continuous load according to claim 1, wherein: the height of annular ya keli outer sleeve and annular ya keli inner sleeve all sets up to two-thirds of the height of annular concrete test block.
4. The apparatus for measuring the diffusion flux of concrete into gas under continuous load according to claim 1, wherein: the lower end face of the upper loading plate and the upper end face of the lower loading plate are respectively provided with an annular groove, the top end of the annular concrete test block is embedded into the annular groove on the upper loading plate, and the tail end of the annular concrete test block is embedded into the annular groove on the lower loading plate.
5. The apparatus for measuring the diffusion flux of concrete into gas under continuous load according to claim 1, wherein: the upper loading plate is connected with the lower loading plate through bolts and nuts, a plurality of bolts are vertically fixed on the edge of the upper end face of the lower loading plate in an annular shape, and the top ends of the bolts penetrate through bolt holes formed in the upper loading plate and are locked through the nuts.
6. The apparatus for measuring the diffusion flux of concrete into gas under continuous load according to claim 1, wherein: epoxy glue is smeared at the coincident joint of the annular acrylic outer sleeve and the annular acrylic inner sleeve.
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Application publication date: 20211102 |