CN203133174U - Non-contact concrete resistivity tester - Google Patents
Non-contact concrete resistivity tester Download PDFInfo
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- CN203133174U CN203133174U CN 201320102332 CN201320102332U CN203133174U CN 203133174 U CN203133174 U CN 203133174U CN 201320102332 CN201320102332 CN 201320102332 CN 201320102332 U CN201320102332 U CN 201320102332U CN 203133174 U CN203133174 U CN 203133174U
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- core tube
- work core
- tube
- concrete
- concrete resistivity
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Abstract
A non-contact concrete resistivity tester is characterized by comprising an inner work core cylinder and an outer work core cylinder. A double-shell cylinder structure comprising bolts is employed between the inner work core cylinder and the outer work core cylinder; the double-shell cylinder structure is provided with an annular iron core and a current tester; the annular iron core and the current tester respectively encircle the upper and lower cylinder open ends of the inner work core cylinder and the outer work core cylinder, the cylinder inner wall of the inner work core cylinder and the cylinder outer wall of the outer work core cylinder; the cylinder inner wall of the outer work core cylinder is provided with an induction coil; the induction coil is connected with the voltage tester outside of the outer work core cylinder through a lead; the iron core on the outer wall of the outer work core cylinder is encircled by a primary coil; and the primary coil is connected with the power supply outside the outer work core cylinder through a lead. According to the non-contact concrete resistivity tester, an electromagnetic mutual inductance principle is followed, the non-contact concrete resistivity tester is buried in concrete by pouring for testing the resistivity of concrete, and the non-contact concrete resistivity tester is suitable for long-term real time monitor on the resistivity change of concrete.
Description
Technical field
The utility model relates to a kind of concrete analyzer, particularly contactless concrete resistivity analyzer.
Background technology
Concrete structure engineering is widely used in fields such as harbour, railway, national defence, industrial and agricultural production and life, but is restricting its usable range because of problems such as permanance.At present, miscellaneous measuring technology and equipment are applied to the concrete context of detection; The conventional concrete damnification recognition method is difficult to reflect original position concrete damage state, and Dynamic Non-Destruction Measurement is to obtain the preferable approach of the true damage of original position concrete in the structure.The concrete resistivity mensuration is a kind of comparatively new non-destructive testing technology, but have simple, fast, cost performance is high and advantage such as remote real time monitoring, will become the new technology of a kind of fast detecting, on-line monitoring and effective evaluation xoncrete structure performance.Concrete resistivity refers to that the unit length concrete hinders the ability that electric current passes through, and can not only reflect concrete density and micromechanism, also can reflect concrete degree of injury exactly; Concrete resistivity is more low, and then corrosion current is just more easy by concrete, and steel bar corrosion deterioration possibility is just more big, so but measure its resistance to corrosion of concrete resistivity effective evaluation and the existing reinforcement corrosion degree of assessment.In addition, measure concrete resistivity for on-line analysis, in real time, accurately and dynamically to monitor its variation significant.Conventional concrete resistivity measurement mode can be divided into contact and contactless two classes; Contact type measurement method commonly used is mainly two electrode method and four electrode methods, and nondestructive determination mainly contains ultrasonic method, radar method, acoustic-emission etc.Yet, still there is deficiency to a certain degree in the existing concrete resistivity measurements, mainly show as traditional detection technology and method not only examined environment and condition influence, and because of the sampling randomness cause the result comparatively unilateral, the on-the-spot detection also can cause the xoncrete structure damage, can't eliminate the influence of contact resistance as two electrode methods, institute's measuring resistance is concrete material resistance, lead and surveying instrument, lead and electrode, the summation of electrode and concrete contact resistance etc., and the material of contact resistance and electrode, size is relevant, can not be equivalent to the resistivity of concrete material truly; Four electrode method can reduce the influence of contact resistance preferably, but electrode is made trouble; Use DC measurement gained resistivity stability and poor repeatability, its conclusion is with a low credibility; Alternating current is measured complicated, and the selection of frequency is also influential to resistivity.By contrast, the noncontact method can be eliminated contact resistance preferably, but adopts DC measurement resistance can produce electric capacity and polarization effect, makes measured value and actual value error very big; The noncontact method is only applicable in the laboratory research to the cement-based material sample of early stage small size at present, and the on-line analysis of actual engineering is used few, and the equipment needed thereby costliness, as the AC impedance spectrometry etc.In view of the deficiency of existing concrete determination of resistivity method, be necessary to develop suitable concrete resistivity analyzer.
Summary of the invention
In order to remedy existing method of testing and equipment in the deficiency aspect the mensuration concrete resistivity, the utility model provides contactless concrete resistivity analyzer.Based on the undesirable mutual electromagnetic inductance principle, bury underground, build and in concrete, can be used for measuring its resistivity, because it is contactless, non-destructive determination device, remedied the deficiency of existing concrete determination of resistivity method and equipment.
In order to realize above-mentioned technical purpose, the technical solution of the utility model is, contactless concrete resistivity analyzer, work core tube and outer work core tube in it is characterized in that comprising, adopt bolt to be assembled into the bivalve tube structure between interior work core tube and the outer work core tube, bolt is that threaded hole is connected the parts that reach fastening bivalve tube structure on through hole and the interior work core tube on the outer work core tube by running through, the bivalve tube structure is provided with annular core and amperometric determination instrument, annular core and amperometric determination instrument are respectively around the last doffing openend of interior work core tube with outer work core tube, the tube inwall of interior work core tube and the drum outer wall of the core tube of working outward, the tube inwall of outer work core tube is provided with inductive coil, inductive coil connects the outer voltage determination instrument of outer work core tube by lead, be wound with primary coil on the iron core at the drum outer wall position of outer work core tube, primary coil connects the outer power supply of outer work core tube by lead.The utility model is based on the undesirable mutual electromagnetic inductance principle, bury underground, build and in concrete, can be used for measuring its resistivity, because it is contactless, non-destructive determination device, remedied the deficiency of existing concrete determination of resistivity method and equipment, have real-time, accurate, simple to operate, long service life and do not have advantage such as polarization, be suitable for the long-term concrete resistivity of monitoring in real time and change.
The utility model is based on the undesirable mutual electromagnetic inductance principle, utilization is wound in iron core primary coil on one side after connecting power supply, the electromagnetic field that changes around it, the magnetic flux path that provides via iron core, the electromagnetic field that changes is put on the concrete in the bivalve body between outer work core tube and interior work core tube, because making, undesirable mutual electromagnetic inductance produces induced voltage and circular current in the concrete, if adopt voltage determination instrument and amperometric determination instrument can record corresponding induced voltage and circular current respectively.During enforcement, need to bury, build described concrete resistivity analyzer underground in concrete detected part; If connect power supply, then primary coil will be as the parts that excite of total system, iron core can provide magnetic flux path, concrete between the body of bivalve and inductive coil are all as secondary coil, utilize induced voltage and the interior circular current of concrete in voltage determination instrument and the amperometric determination instrument mensuration inductive coil respectively, can obtain concrete resistivity.
Work core tube was concentric tube with outer work core tube in feature of the present utility model also was.
Feature of the present utility model also is casting concrete between the cylindrical shell of bivalve.
Feature of the present utility model is that also the inductive coil employing is built or extrusion forming process is integrated with in outer work core tube.
Feature of the present utility model also be iron core be in part in the work core tube adopt build or extrusion forming process be integrated in in the work core tube.
Feature of the present utility model is that also described power supply for the power supply of different frequency with the alternating current of power can be provided, is the electric supply installation of total system.
Feature of the present utility model is that also described voltage tester is the high-precision AC voltage tester, and in order to measure the induced voltage that inductive coil produces, its value also is the induced voltage in the concrete between the cylindrical shell of bivalve.
Feature of the present utility model is that also described amperometric determination instrument is the high-precision AC current tester, can measure the circular current that produces in the concrete mutual inductance process that the bivalve cylindrical shell builds.
Feature of the present utility model is that also described iron core is that the very capable magnetic siliconized plate of magnetic conduction is made, and the magnetic flux path effect that provides is provided.
Feature of the present utility model is that also described outer work core tube adopts phenoplast, polyurethane plastics, epoxy plastics, unsaturated polyester plastic, organic siliconresin and the allyl resin of non-conductive class and polymer-modified resinous material thereof to make, be that two and half cylindrical shells adopt bolted to become one, but have the through hole of two or more through bolts above half cylindrical shell.
Feature of the present utility model is that also described bolt is that phenoplast, polyurethane plastics, epoxy plastics, unsaturated polyester plastic, organic siliconresin and allyl resin and the polymer-modified resinous material thereof of non-conductive class made, its termination is hexangle type, have external thread on the screw rod, can run through outer work core tube, and can utilize screw thread to be fixed on the interior work core tube, play core tube and the effect of fastening as one of interior work core tube of working outward.
Feature of the present utility model also be described in phenoplast, polyurethane plastics, epoxy plastics, unsaturated polyester plastic, organic siliconresin and allyl resin and the polymer-modified resinous material thereof of work core tube non-conductive class make, employing is built or extrusion forming process is fixed one side of iron core and amperometric determination instrument, and its surface has hole and the hole inside surface has screw thread in order to fastening bolt.
Feature of the present utility model is that also described primary coil is enameled wire loop, and it is by wire connecting power and be wound in iron core on one side, with the electromagnetic field that changes, is the parts that excite of total system.
Feature of the present utility model is that also described inductive coil is to be divided into two sections enameled wire loop, the termination of one section is insertion slot type, the termination of another section is corresponding plug-type, inductive coil is used builds or extrusion forming process is integrated in the outer work core tube, during assembling the plug of inductive coil is connected with the slot end and gets final product, two ends connect the voltage determination instrument by lead in addition.
Feature of the present utility model is that also described outer work core tube and interior work core tube utilize bolted to be the bivalve tube structure between the two, but casting concrete therebetween, this concrete can be used as secondary coil, and the circular current that produces in it can utilize the amperometric determination instrument namely to record.
The beneficial effects of the utility model are:
1, the utility model proposes based on the undesirable mutual electromagnetic inductance principle, has real-time monitoring, measures fast, repeatability is good and construct advantage such as novelty, belongs to harmless, contactless concrete resistivity determination techniques, has remedied the deficiency of existing assay method and equipment.
2, the utility model eliminated that electrode separates with the contraction that the cement-based material contact produces in the test of traditional resistor rate, problems such as electrode corrosion, contact resistance, electrode interference, polarization and capacity effect, improved the precision of concrete resistivity test.
3, adopt the utility model can effectively get rid of the external environment factor to the influence of proving installation, can measure concrete resistivity variation under the varying environment condition for a long time, its simple structure, easy operating.
Description of drawings
Fig. 1 is the structural representation of the utility model embodiment concrete resistivity analyzer;
Fig. 2 is the outer work core-tube structure sectional view of the utility model concrete resistivity analyzer;
Fig. 3 is the interior work core-tube structure sectional view of the utility model concrete resistivity analyzer;
Wherein 1 is power supply, and 2 is voltage tester, and 3 is outer work core tube, and 4 is interior work core tube, and 5 is bolt, and 6 is primary coil, and 7 is inductive coil, and 8 are the amperometric determination instrument, and 9 is lead, and 10 is iron core, 11 threaded holes, 12 through holes.
Embodiment
Following embodiment is to the further specifying of the utility model technology contents, but is not the restriction to the utility model flesh and blood.
The concrete resistivity analyzer comprises power supply 1, amperometric determination instrument 8, voltage determination instrument 2, iron core 10, work core tube 3, lead 9, interior work core tube 4, bolt 5,11 threaded holes, 12 through holes, primary coil 6 and inductive coil 7 outward.Work core tube 4 and outer work core tube 3 in the concrete resistivity analyzer comprises, adopt bolt 5 to be assembled into the bivalve tube structure between interior work core tube 4 and the outer work core tube 3, bolt 5 is that threaded hole 11 is connected the parts that reach fastening bivalve tube structure on through hole 12 and the interior work core tube 4 on the outer work core tube 3 by running through, the bivalve tube structure is provided with an annular core 10 and an amperometric determination instrument 8, annular core 10 and amperometric determination instrument 8 are respectively around the last doffing openend of interior work core tube 4 with outer work core tube 3, the tube inwall of interior work core tube 4 and the drum outer wall of the core tube 3 of working outward, the tube inwall of outer work core tube 3 is provided with inductive coil 7, voltage determination instrument 2 outside inductive coil 7 connects by lead 9 outside the work core tube 3, be wound with primary coil 6 on the iron core 10 at the drum outer wall position of the outer core tube 3 of working, the power supply 1 outside primary coil 6 connects by lead 9 outside the work core tube 3.Fig. 1 is the structural representation of the utility model embodiment concrete resistivity analyzer, as shown in Figure 1, inductive coil 7 connects voltage determination instrument 2 by lead 9, and be used and build or extrusion forming process is integrated in the outer work core tube 3, primary coil 6 connects power supply 1 by lead 9, and be wound in one side of iron core 10, and one side of iron core 10 corresponding symmetrical limits and amperometric determination instrument 8 all be used build or extrusion forming process be integrated in in the work core tube 4, outer work core tube 3 and interior work core tube 4 adopt bolt 5 to be assembled into the bivalve tube structure between the two, but casting concrete between this bivalve cylindrical shell.Fig. 2 is the outer work core-tube structure sectional view of the utility model concrete resistivity analyzer, as shown in Figure 2, outer work core tube 3 is that two thin-walled half cylindrical shells adopt the hex bolts 5 fastening integral body that become, have two or more through holes 12 that run through for bolt 5 on it, contain in the core tube 3 of working outward to adopt and build or the inductive coil 7 of extrusion forming process.Fig. 3 is the interior work core-tube structure sectional view of the utility model concrete resistivity analyzer, as shown in Figure 3, interior work core tube 4 is the solid cylindrical shell with certain size, and adopt and to build or extrusion forming process becomes one one side and the amperometric determination instrument 8 of iron core 10 on one side, two or morely on it have a threaded hole 11, itself and outer work core tube 3 can be assembled into integral body by bolt 5.
Work core tube 4 was concentric tube with outer work core tube 3 in feature of the present utility model also was.
Feature of the present utility model also is casting concrete between the cylindrical shell of bivalve.
Feature of the present utility model is that also inductive coil 7 employings are built or extrusion forming process is integrated in the outer work core tube 3.
Feature of the present utility model also be iron core 10 be in part in the work core tube 4 adopt build or extrusion forming process be integrated in in the work core tube.
Feature of the present utility model is that also power supply 1 for the power supply of different frequency with the alternating current of power can be provided, is the electric supply installation of total system.
Feature of the present utility model is that also described voltage tester 2 is the high-precision AC voltage tester, and in order to measure the induced voltage that inductive coil 7 produces, its value also is the induced voltage in the concrete between the cylindrical shell of bivalve.
Feature of the present utility model is that also described amperometric determination instrument 8 is the high-precision AC current tester, can measure the circular current that produces in the concrete mutual inductance process that the bivalve cylindrical shell builds.
Feature of the present utility model is that also described iron core 10 makes for the very capable magnetic siliconized plate of magnetic conduction, and the magnetic flux path effect that provides is provided.
Feature of the present utility model is that also described outer work core tube 3 makes for the phenoplast of non-conductive class, polyurethane plastics, epoxy plastics, unsaturated polyester plastic, organic siliconresin and allyl resin and polymer-modified resinous material thereof, be that two and half cylindrical shells adopt bolt 5 fastening becoming one, but have the through hole of two or more through bolts 5 above half cylindrical shell.
Feature of the present utility model is that also described bolt 5 makes for the phenoplast of non-conductive class, polyurethane plastics, epoxy plastics, unsaturated polyester plastic, organic siliconresin and allyl resin and polymer-modified resinous material thereof, its termination is hexangle type, have external thread on the screw rod, can run through outer work core tube 3, and can utilize screw thread to be fixed on the interior work core tube 4, play core tube 3 and interior work core tube 4 effects of fastening as one of working outward.
Feature of the present utility model also be described in work core tube 4 make for the phenoplast of non-conductive class, polyurethane plastics, epoxy plastics, unsaturated polyester plastic, organic siliconresin and allyl resin and polymer-modified resinous material thereof, employing is built or extrusion forming process is fixed one side of iron core 10 and amperometric determination instrument 8, and its surface has hole and the hole inside surface has screw thread in order to fastening bolt 5.
Feature of the present utility model is that also described primary coil 6 is enameled wire loop, and it connects power supply 1 and be wound in iron core 10 on one side by lead 9, to change electromagnetic field, is the parts that excite of total system.
Feature of the present utility model is that also described inductive coil 7 is for being divided into two sections enameled wire loop, the termination of one section is insertion slot type, the termination of another section is corresponding plug-type, inductive coil 7 is used builds or extrusion forming process is integrated in the outer work core tube 3, during assembling the plug of inductive coil 3 is connected with the slot end and gets final product, two ends connect voltage determination instrument 2 to obtain induced voltage indirectly by lead 9 in addition.
Feature of the present utility model is that also described outer work core tube 3 and interior work core tube 4 utilize between the two that bolt 5 is fastening to be the bivalve tube structure, but casting concrete between this structure, and concrete can play the secondary coil effect, and the circular current that produces can utilize amperometric determination instrument 8 to record.
The utility model is based on electromagnetic induction principle, utilization is wound in iron core 10 primary coil 6 on one side after connecting power supply 1, the electromagnetic field that changes around it, the magnetic flux path that provides via iron core 10, the electromagnetic field that changes is put on the concrete in the bivalve body of 4 in outer work core tube 3 and interior work core tube, because making, undesirable mutual electromagnetic inductance produces induced voltage and circular current in the concrete, if adopt voltage determination instrument 2 and amperometric determination instrument 8 can record induced voltage and circular current.
During enforcement, need to bury, build described concrete resistivity analyzer underground in concrete detected part; If connect power supply 1, then primary coil 6 will be as exciting parts, iron core 10 can provide magnetic flux path, concrete between the body of bivalve and inductive coil 7 are all as secondary coil, utilize induced voltage and the interior circular current of concrete in voltage determination instrument 2 and the amperometric determination instrument 8 mensuration inductive coils 7 respectively, can obtain concrete resistivity, shown in (1).
In the formula: U is induced voltage, and I is circular current, r
1Be the internal diameter of outer work core tube, r
0Be the external diameter of interior work core tube, h is the height of outer work core tube.
Claims (14)
1. contactless concrete resistivity analyzer, work core tube and outer work core tube in it is characterized in that comprising, adopt bolt to be assembled into the bivalve tube structure between interior work core tube and the outer work core tube, bolt is that threaded hole is connected the parts that reach fastening bivalve tube structure on through hole and the interior work core tube on the outer work core tube by running through, the bivalve tube structure is provided with annular core and amperometric determination instrument, annular core and amperometric determination instrument are respectively around the last doffing openend of interior work core tube with outer work core tube, the tube inwall of interior work core tube and the drum outer wall of the core tube of working outward, the tube inwall of outer work core tube is provided with inductive coil, inductive coil connects the outer voltage determination instrument of outer work core tube by lead, be wound with primary coil on the iron core at the drum outer wall position of outer work core tube, primary coil connects the outer power supply of outer work core tube by lead.
2. contactless concrete resistivity analyzer according to claim 1 is characterized in that, interior work core tube is concentric tube with outer work core tube.
3. contactless concrete resistivity analyzer according to claim 1 is characterized in that casting concrete between the cylindrical shell of bivalve.
4. contactless concrete resistivity analyzer according to claim 3 is characterized in that, inductive coil is integrated in the outer work core tube.
5. contactless concrete resistivity analyzer according to claim 1 is characterized in that, partly integrated in interior work core tube in iron core is in the work core tube.
6. according to the described contactless concrete resistivity analyzer of arbitrary claim in the claim 1 to 5, it is characterized in that described power supply is for providing the power supply of different frequency with the alternating current of power.
7. according to the described contactless concrete resistivity analyzer of arbitrary claim in the claim 1 to 5, it is characterized in that described voltage tester is the high-precision AC voltage tester, in order to measure the induced voltage in the inductive coil.
8. according to the described contactless concrete resistivity analyzer of arbitrary claim in the claim 1 to 5, it is characterized in that, described amperometric determination instrument is the high-precision AC current tester, can measure the circular current that concrete produces in the undesirable mutual electromagnetic inductance process between the cylindrical shell of bivalve.
9. according to the described contactless concrete resistivity analyzer of arbitrary claim in the claim 1 to 5, it is characterized in that described iron core is the magnetic siliconized plate.
10. according to the described contactless concrete resistivity analyzer of arbitrary claim in the claim 1 to 5, it is characterized in that, described outer work core tube is two and half cylindrical shells, but have the through hole of two or more through bolts on half cylindrical shell, the outer work core tube that two and half cylindrical shells adopt bolted to become one.
11. according to the described contactless concrete resistivity analyzer of arbitrary claim in the claim 1 to 5, it is characterized in that bolt end is hexangle type, screw rod has screw thread outward, screw rod runs through outer work core tube, and the core tube of working outward utilizes screw thread to be fixed on the interior work core tube.
12. according to the described contactless concrete resistivity analyzer of arbitrary claim in the claim 1 to 5, it is characterized in that, work core tube is fixed one side of iron core and amperometric determination instrument in described, interior work core tube surface have contain screw thread hole with fastening bolt.
13. according to the described contactless concrete resistivity analyzer of arbitrary claim in the claim 1 to 5, it is characterized in that, described primary coil is enameled wire loop, primary coil is by wire connecting power and be wound in iron core on one side, with the electromagnetic field that changes, be the parts that excite of total system.
14. according to the described contactless concrete resistivity analyzer of arbitrary claim in the claim 1 to 5, it is characterized in that, described inductive coil is to be divided into two sections enameled wire loop, one end termination of one section is insertion slot type, the one end termination of another section is corresponding plug-type, inductive coil is integrated in the outer work core tube, and the two ends in addition of two sections enameled wire loops connect the voltage determination instrument by lead respectively.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201320102332 CN203133174U (en) | 2013-03-06 | 2013-03-06 | Non-contact concrete resistivity tester |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201320102332 CN203133174U (en) | 2013-03-06 | 2013-03-06 | Non-contact concrete resistivity tester |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203133174U true CN203133174U (en) | 2013-08-14 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201320102332 Expired - Fee Related CN203133174U (en) | 2013-03-06 | 2013-03-06 | Non-contact concrete resistivity tester |
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| CN (1) | CN203133174U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103149440A (en) * | 2013-03-06 | 2013-06-12 | 中南大学 | Non-contact type concrete resistivity testing instrument |
-
2013
- 2013-03-06 CN CN 201320102332 patent/CN203133174U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103149440A (en) * | 2013-03-06 | 2013-06-12 | 中南大学 | Non-contact type concrete resistivity testing instrument |
| CN103149440B (en) * | 2013-03-06 | 2015-11-25 | 中南大学 | Contactless concrete resistivity analyzer |
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Legal Events
| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20130814 Termination date: 20140306 |