阅读说明：本技术 一种电化学萃取钢筋混凝土中氯离子改进方法 (Chloride ion improved method in a kind of electrochemistry extraction armored concrete ) 是由 李悦 张国胜 王子赓 于 2019-09-16 设计创作，主要内容包括：一种电化学萃取钢筋混凝土中氯离子改进方法,涉及钢筋混凝土电化学萃取的领域。其中1)在锈蚀的钢筋混凝土结构上按平行网格形状钻出孔洞。2)对钻孔后的钢筋混凝土结构进行饱水预湿处理使混凝土保护层润湿。3)将预制高导电性磷酸镁水泥砂浆棒插入预制孔洞中；4)将预制磷酸镁水泥砂浆棒作为电化学萃取的外部阳极,锈蚀钢筋混凝土结构中钢筋作为阴极,在通电条件下把混凝土结构中的氯离子萃取到预制砂浆棒的端部。5)氯离子萃取结束后将露出混凝土试件表面的预制磷酸镁水泥砂浆棒切除。本发明不用铺设钢丝网、钛网,节约成本；不用在构件上设置水槽浸泡电解液,工艺简单方便可行；氯离子的萃取效率更高,且萃取结束后构件强度不下降。(Chloride ion improved method in a kind of electrochemistry extraction armored concrete, is related to the field of armored concrete electrochemistry extraction.Wherein hole 1) is drilled out by parallel grid shape on the reinforced concrete structure of corrosion.2) carrying out full water pre-wetted treatment to the reinforced concrete structure after drilling soaks concrete cover.3) prefabricated high conductivity magnesium phosphate cement mortar bars are inserted into prefabricated hole；4) external anode for extracting prefabricated magnesium phosphate cement mortar bars as electrochemistry, reinforcing bar is extracted into the chloride ion in concrete structure under power on condition the end of prefabricated mortar bars as cathode in CORRODED REINFORCED CONCRETE STRUCTURE.5) the prefabricated magnesium phosphate cement mortar bars for exposing concrete sample surface are cut off after chloride ion extraction.The present invention does not have to be laid with steel wire, titanium net, save the cost；Electrolyte is impregnated without sink is arranged on component, simple process facilitates feasible；The extraction efficiency of chloride ion is higher, and component strength does not decline after extraction.)

1. chloride ion improved method in a kind of electrochemistry extraction armored concrete, it is characterised in that: 1) in the reinforced concrete of corrosion Drill out hole by parallel grid shape in soil structure, the horizontal and vertical spacing of grid element center point is respectively 20-40cm, hole it is straight Diameter is 3-5cm, and the depth of hole reaches thickness of concrete cover, is then stopped when arriving at rebar surface；2) to the steel after drilling Tendon concrete structure, which carries out full water pre-wetted treatment, soaks concrete cover；3) prefabricated magnesium phosphate cement mortar bars, then exist The magnesium phosphate cement net slurry of one layer of 1-2mm thickness is smeared on its surface, then mortar bars are inserted into prefabricated hole, and mortar bars length is 8- 10cm, and guarantee to expose mortar bars 5-7cm in concrete surface；4) using prefabricated magnesium phosphate cement mortar bars as electrochemistry The external anode of extraction, reinforcing bar is as cathode in CORRODED REINFORCED CONCRETE STRUCTURE, in concrete structure under power on condition Chloride ion is extracted into the end of prefabricated mortar bars；5) the prefabricated phosphoric acid on concrete sample surface will be exposed after chloride ion extraction The excision of magnesium cement mortar stick.

2. a kind of electrochemistry according to claim 1 extracts chloride ion improved method in armored concrete, wherein step 2) Be characterized in that, the pre-wetted treatment be concrete surface water spray after be covered on again with the wet sponge for being full of tap water it is mixed Xtah Crude Clay structure surface, and moisturizing 3 days or more, soak concrete cover.

3. a kind of electrochemistry according to claim 1 extracts chloride ion improved method in armored concrete, wherein step 3) Be characterized in that, magnesium phosphate cement net slurry the preparation method comprises the following steps:

Raw material includes MgO, the hereinafter referred to as M of 1600 DEG C of calcinings, with PHOSPHORIC ACID TECH.GRADE potassium dihydrogen hereinafter referred to as P, mole of the two Ratio M/P:4~5；

Raw material includes retarder borax, and volume is the 5%~15% of MgO mass；

Raw material includes length 1-2mm carbon fiber or graphene oxide as conductive material, volume be MgO mass 0.01%~ 0.05%；

The mass ratio of water and the above solid raw material: 0.14~0.16；

Solid material is stirred evenly first, water is then added and is stirred for 2~3 minutes, magnesium phosphate cement should be in 20 minutes Using finishing.

4. a kind of electrochemistry according to claim 3 extracts chloride ion improved method in armored concrete, wherein step 3) Be characterized in that, prefabricated magnesium phosphate cement mortar bars the preparation method comprises the following steps:

Using magnesium phosphate cement as cementitious material；

Using the sand of fineness modulus 2.7~3.3 as aggregate, the mass ratio of magnesium phosphate cement and sand is 1:1.5~1:2；

Foaming agent uses bicarbonate, and volume is the 5-10% of MgO mass；

Various components are weighed in proportion, first stir evenly solid powder, are then added solid powder quality 15%-20%'s Water, stirring obtained magnesium phosphate cement mortar after 2~3 minutes；It is identical as concrete hole that mortar is poured into length 8-10cm, diameter Cylindrical die in conserve 7~10 days, saved under environment indoors after demoulding；

Use the Na that be 10 in pH before magnesium phosphate cement mortar bars₃BO₃It is impregnated 24 hours in solution.

5. a kind of electrochemistry according to claim 1 extracts chloride ion improved method in armored concrete, wherein step 4) It is characterized in that, the external anode that magnesium phosphate cement mortar bars are extracted as electrochemistry, the Corrosion Reinforcement exposed in hole is made For the cathode of electrochemistry extraction, it is connected to external dc power supply with conducting wire respectively, the specific surface area current density relative to reinforcing bar Control is in 2.5A/m²~3A/m², conduction time 30d~42d, to corrosion concrete sample dechlorinate.

6. chloride ion improved method in a kind of electrochemistry extraction armored concrete according to claim 1, wherein step 5) It is characterized in that, the end portion that prefabricated magnesium phosphate cement mortar bars are higher by concrete surface is cut away after extraction.

Technical field

The invention belongs to the technical fields of armored concrete electrochemistry, are related to a kind of changing for armored concrete electrochemical dechlorination Into method.

Background technique

Armored concrete is the most widely used construction material in the world today, but in reinforced concrete structure military service process In, the steel bar corrosion due to caused by the erosion of villaumite is the most common failure mode of current concrete structure.Steel bar corrosion causes The destruction of concrete structure makes building there are huge security risk, its service life of serious curtailment.In recent years, exploitation Electrochemical desalting technology can effectively remove the chloride ion in concrete, reduce the corrosion risk of reinforcing bar, solve conventional maintenance method The problem for causing concrete structure service life difference improves the durability of concrete structure.

Existing electrochemical dechlorination technical matters is, using reinforcement in concrete as cathode, applied external anode, in anode and cathode Between apply electric field, negatively charged chloride ion is transmitted to the electrolyte outside concrete by electric field action by the hole in concrete In, to reduce Chloride Ion in Concrete content, inhibit the corrosion of reinforcing bar, common external anode material have ordinary steel silk screen, Titanium net, carbon fiber；But there are certain drawbacks during dechlorination for above-mentioned dechlorination device: ordinary steel wire network capacity easy-to-rust, dechlorination It is ineffective；And titanium net and carbon fiber price are expensive, are laid with more difficult, it is difficult to which large-area applications are in Practical Project.More than and Device requires that sink is arranged on component, makes component leaching in the electrolytic solution, to chloride ion is extracted into electrolyte, still In practical projects, sink is arranged to components such as column, beam, plate, shear wall, ceilings, making component leaching is extremely tired in the electrolytic solution Difficult.

Prefabricated high conductivity magnesium phosphate cement mortar bars are inserted into Corroded Reinforced Concrete knot in view of the above-mentioned problems, proposing In structure be used as anode, chloride ion is extracted into the end of prefabricated mortar bars, after will expose concrete sample surface it is prefabricated The excision of magnesium phosphate cement mortar bars.The present invention does not have to be laid with steel wire, titanium net, carbon cloth, save the cost；Less it is used in Sink is set on component and impregnates electrolyte, simple process facilitates feasible；The extraction efficiency of chloride ion is higher, and structure after extraction Part intensity does not influence durability and the safety of structure, has broad application prospects.

Summary of the invention

There are problems that chlorine removal rate is low Conventional electrochemical dechlorination method, involve great expense, complicated construction technique, proposes A kind of chlorine removal rate is higher, save the cost, the feasible extraction chloride ion of simple process improve new method.

Chloride ion improved method in a kind of electrochemistry extraction armored concrete, extracts chloride ion step as shown in Figure 1, it is special Sign is: 1) drilling out hole by parallel grid shape on the reinforced concrete structure of corrosion, grid element center point is horizontal and vertical Spacing is respectively 20-40cm, and the diameter of hole is 3-5cm, and the depth of hole reaches thickness of concrete cover, when arrival reinforcing bar Surface then stops.2) carrying out full water pre-wetted treatment to the reinforced concrete structure after drilling soaks concrete cover.3) pre- Then high conductivity magnesium phosphate cement mortar bars processed smear the magnesium phosphate cement net slurry of one layer of 1-2mm thickness on its surface, then by sand It starches in stick insertion prefabricated hole, mortar bars length is 8-10cm, and guarantees to expose mortar bars 5-7cm in concrete surface； 4) external anode for extracting prefabricated magnesium phosphate cement mortar bars as electrochemistry, reinforcing bar conduct in CORRODED REINFORCED CONCRETE STRUCTURE Cathode is extracted into the chloride ion in concrete structure under certain power on condition the end of prefabricated mortar bars.5) chloride ion extracts The prefabricated magnesium phosphate cement mortar bars for exposing concrete sample surface are cut off after taking.

The pre-wetted treatment is to be covered on coagulation with the wet sponge for being full of tap water again after concrete surface water spray Soil structure surface, and moisturizing 3 days or more, soak concrete cover.

The magnesium phosphate cement net slurry the preparation method comprises the following steps:

(1) raw material includes the MgO (abbreviation M) and PHOSPHORIC ACID TECH.GRADE potassium dihydrogen (abbreviation P) of 1600 DEG C of calcinings, mole of the two Ratio M/P:4~5；

(2) raw material includes retarder borax, and volume is the 5%~15% of MgO mass；

(3) raw material includes length 1-2mm carbon fiber or graphene oxide as conductive material, and volume is MgO mass 0.01%~0.05%；

(4) mass ratio of water and the above solid raw material: 0.14~0.16；

(5) preparation method of net slurry is: weigh various components in proportion, first stir evenly solid material, then plus Enter water to be stirred for 2~3 minutes, magnesium phosphate cement should be in 20 minutes using finishing.

The prefabricated high conductivity magnesium phosphate cement mortar bars the preparation method comprises the following steps:

(1) using identical magnesium phosphate cement in composition and above-mentioned 3 as cementitious material；

(2) aggregate is used as using the sand of fineness modulus 2.7~3.3, the mass ratio of magnesium phosphate cement and sand is 1:1.5 ~1:2；

(3) foaming agent uses technical grade bicarbonate, and volume is the 5-10% of MgO mass.

(4) various components are weighed in proportion, first stir evenly solid powder, and solid powder quality is then added The water of 15%-20%, stirring obtained magnesium phosphate cement mortar after 2~3 minutes.Mortar is poured into length 8-10cm, diameter and is mixed It conserves 7~10 days in the identical cylindrical die of solidifying soil hole, is saved under environment indoors after demoulding.

(5) using the Na that be 10 in pH before magnesium phosphate cement mortar bars₃BO₃It is impregnated 24 hours in solution.

The implementation steps of extraction chloride ion are characterized in that: using prefabricated high conductivity magnesium phosphate cement mortar bars as electrification The external anode of extraction is learned, the cathode that the Corrosion Reinforcement exposed in hole is extracted as electrochemistry is connected to conducting wire respectively External dc power supply, current density are controlled in 2.5A/m²~3A/m²(specific surface area relative to reinforcing bar), conduction time 30d~ 42d dechlorinates to corrosion concrete sample.Prefabricated high conductivity magnesium phosphate cement mortar bars are higher by coagulation after extraction The end portion on native surface is cut away.

Detailed description of the invention

Fig. 1 is chloride ion extraction step schematic diagram

Specific embodiment

Further to embody effect of the invention, below with reference to specific application example, the present invention will be described in detail.

Example 1:

Chloride ion improved method in a kind of electrochemistry extraction armored concrete, is applied to having a size of long 300cm* wide 300cm* The Corroded Reinforced Concrete plate of high 12cm, magnesium phosphate cement net slurry used the preparation method comprises the following steps:

(1) raw material includes the MgO (abbreviation M) and PHOSPHORIC ACID TECH.GRADE potassium dihydrogen (abbreviation P) of 1600 DEG C of calcinings, mole of the two Ratio M/P:4；

(2) raw material includes retarder borax, and volume is the 5% of MgO mass；

(3) for raw material graphene oxide as conductive material, volume is the 0.01% of MgO mass；

(4) mass ratio of water and the above solid raw material: 0.14；

(5) preparation method of net slurry is: weigh various components in proportion, first stir evenly solid material, then plus Enter water to be stirred for 2 minutes, magnesium phosphate cement should be in 20 minutes using finishing.

Prefabricated high conductivity magnesium phosphate cement mortar bars the preparation method comprises the following steps:

(1) using composition magnesium phosphate cement net slurry same as described above as cementitious material；

(2) aggregate is used as using the sand of fineness modulus 2.7, the mass ratio of magnesium phosphate cement and sand is 1:1.5；

(3) foaming agent uses technical grade bicarbonate, and specifically sodium bicarbonate following embodiment is identical but not limited to this, Its volume is the 5% of MgO mass.

(4) various components are weighed in proportion, first stir evenly solid powder, and solid powder quality 15% is then added Water, stirring 3 minutes after obtain magnesium phosphate cement mortar.Mortar is poured into length 8cm, diameter and the identical circle of concrete hole It conserves 7 days in cylindrical mold, is saved under environment indoors after demoulding.

(5) using the Na that be 10 in pH before magnesium phosphate cement mortar bars₃BO₃It is impregnated 24 hours in solution.

It extracts the implementation steps of chloride ion: 1) pressing parallel grid shape drilling bore hole on the reinforced concrete slab structure of corrosion Hole, grid element center point horizontal spacing 40cm, longitudinal pitch 40cm, the diameter of hole is 3cm, and the depth of hole reaches concrete guarantor Covering thickness then stops when arriving at rebar surface.2) it sprays water to the reinforced concrete slab structure after drilling, then again with being full of oneself The wet sponge of water is covered on concrete board constructions surface, and moisturizing 3 days or more, soaks concrete cover.3) pre- The magnesium phosphate cement net slurry of one layer of 1mm thickness is smeared on high conductivity magnesium phosphate cement mortar bars surface processed, then mortar bars are inserted into advance In drilling hole.4) external anode for extracting prefabricated high conductivity magnesium phosphate cement mortar bars as electrochemistry, it is naked in hole The cathode that the Corrosion Reinforcement of exposing is extracted as electrochemistry is connected to external dc power supply, current density control with conducting wire respectively In 3A/m²(specific surface area relative to reinforcing bar), conduction time 42d dechlorinate to corrosion concrete slab.5) after extracting The end portion that prefabricated high conductivity magnesium phosphate cement mortar bars are higher by concrete surface is cut away.

Example 2:

Chloride ion improved method in a kind of electrochemistry extraction armored concrete, is applied to having a size of long 400cm* wide 35cm* The Corroded Reinforced Concrete Beam of high 40cm, magnesium phosphate cement net slurry used the preparation method comprises the following steps:

(1) raw material includes the MgO (abbreviation M) and PHOSPHORIC ACID TECH.GRADE potassium dihydrogen (abbreviation P) of 1600 DEG C of calcinings, mole of the two Ratio M/P:4.5；

(2) raw material includes retarder borax, and volume is the 10% of MgO mass；

(3) raw material includes length 1-2mm carbon fiber as conductive material, and volume is the 0.03% of MgO mass；

(4) mass ratio of water and the above solid raw material: 0.15；

(5) preparation method of net slurry is: weigh various components in proportion, first stir evenly solid material, then plus Enter water to be stirred for 2.5 minutes, magnesium phosphate cement should be in 20 minutes using finishing.

Prefabricated high conductivity magnesium phosphate cement mortar bars the preparation method comprises the following steps:

(the 1 magnesium phosphate cement net slurry for using composition same as described above is as cementitious material；

(2) aggregate is used as using the sand of fineness modulus 3, the mass ratio of magnesium phosphate cement and sand is 1:1.7；

(3 foaming agents use technical grade bicarbonate, and volume is the 8% of MgO mass.

(4) various components are weighed in proportion, first stir evenly solid powder, and solid powder quality 17% is then added Water, stirring 2.5 minutes after obtain magnesium phosphate cement mortar.It is identical that mortar is poured into length 9cm, diameter and concrete hole It conserves 8 days in cylindrical die, is saved under environment indoors after demoulding.

(5) using the Na that be 10 in pH before magnesium phosphate cement mortar bars₃BO₃It is impregnated 24 hours in solution.

It extracts the implementation steps of chloride ion: 1) pressing parallel grid shape drilling bore hole in the armored concrete girder construction of corrosion Hole, grid element center point horizontal spacing 25cm, longitudinal pitch 30cm, the diameter of hole is 4cm, and the depth of hole reaches concrete guarantor Covering thickness then stops when arriving at rebar surface.2) it sprays water to the armored concrete girder construction after drilling, then again with being full of oneself The wet sponge of water is covered on beams of concrete body structure surface, and moisturizing 3 days or more, soaks concrete cover.3) pre- The magnesium phosphate cement net slurry of one layer of 1.5mm thickness is smeared on high conductivity magnesium phosphate cement mortar bars surface processed, then mortar bars are inserted into In prefabricated hole.4) external anode for extracting prefabricated high conductivity magnesium phosphate cement mortar bars as electrochemistry, in hole The cathode that the Corrosion Reinforcement exposed is extracted as electrochemistry is connected to external dc power supply, current density control with conducting wire respectively System is in 2.7A/m²(specific surface area relative to reinforcing bar), conduction time 36d dechlorinate to corrosion beams of concrete.5) extraction knot The end portion that prefabricated high conductivity magnesium phosphate cement mortar bars are higher by concrete surface is cut away after beam.

Example 3:

Chloride ion improved method in a kind of electrochemistry extraction armored concrete, is applied to having a size of long 40cm* wide 40cm* high The Corroded Reinforced Concrete column of 300cm, magnesium phosphate cement net slurry used the preparation method comprises the following steps:

(1) raw material includes the MgO (abbreviation M) and PHOSPHORIC ACID TECH.GRADE potassium dihydrogen (abbreviation P) of 1600 DEG C of calcinings, mole of the two Ratio M/P:5；

(2) raw material includes retarder borax, and volume is the 15% of MgO mass；

(3) raw material includes length 1-2mm carbon fiber as conductive material, and volume is the 0.05% of MgO mass；

(4) mass ratio of water and the above solid raw material: 0.16；

(5) preparation method of net slurry is: weigh various components in proportion, first stir evenly solid material, then plus Enter water to be stirred for 3 minutes, magnesium phosphate cement should be in 20 minutes using finishing.

Prefabricated high conductivity magnesium phosphate cement mortar bars the preparation method comprises the following steps:

(the 1 magnesium phosphate cement net slurry for using composition same as described above is as cementitious material；

(2) aggregate is used as using the sand of fineness modulus 3.3, the mass ratio of magnesium phosphate cement and sand is 1:2；

(3 foaming agents use technical grade bicarbonate, and volume is the 10% of MgO mass.

(4) various components are weighed in proportion, first stir evenly solid powder, and solid powder quality 20% is then added Water, stirring 3 minutes after obtain magnesium phosphate cement mortar.It is identical that mortar is poured into length 10cm, diameter and concrete hole It conserves 10 days in cylindrical die, is saved under environment indoors after demoulding.

(5) using the Na that be 10 in pH before magnesium phosphate cement mortar bars₃BO₃It is impregnated 24 hours in solution.

It extracts the implementation steps of chloride ion: 1) pressing parallel grid shape drilling bore hole on the armored concrete rod structure of corrosion Hole, grid element center point horizontal spacing 20cm, longitudinal pitch 20cm, the diameter of hole is 5cm, and the depth of hole reaches concrete guarantor Covering thickness then stops when arriving at rebar surface.2) it sprays water to the armored concrete rod structure after drilling, then again with being full of oneself The wet sponge of water is covered on concrete column structure surface, and moisturizing 3 days or more, soaks concrete cover.3) pre- The magnesium phosphate cement net slurry of one layer of 2mm thickness is smeared on high conductivity magnesium phosphate cement mortar bars surface processed, then mortar bars are inserted into advance In drilling hole.4) external anode for extracting prefabricated high conductivity magnesium phosphate cement mortar bars as electrochemistry, it is naked in hole The cathode that the Corrosion Reinforcement of exposing is extracted as electrochemistry is connected to external dc power supply, current density control with conducting wire respectively In 2.5A/m²(specific surface area relative to reinforcing bar), conduction time 30d dechlorinate to corrosion concrete column.5) extraction terminates The end portion that prefabricated high conductivity magnesium phosphate cement mortar bars are higher by concrete surface is cut away afterwards.

Experimental result

After dechlorination, referring to the Water soluble chloride ion in SL352-2006 " concrete for hydraulic structure testing regulations " measurement concrete Concentration, the chlorine removal rate being calculated are as shown in table 1；According to " the normal concrete mechanical property test side GB/T50081-2002 Method standard " dechlorination front and back is tested by the unbearable compression strength for sampling obtained surface of concrete structure test block, using the present invention Concrete test block intensity is " intensity ratio " divided by concrete test block strength definition before dechlorinating after improved method dechlorination, as a result such as table 2 It is shown.

(1) existing reinforced concrete member chlorine removal rate

The chlorine removal rate (wt%) of component is corroded in 1 example 1-3 of table

Group number	Example 1	Example 2	Example 3
				Chlorine removal rate (%)	84.4	82.6	87.3

(2) Corroded Reinforced Concrete test specimen dechlorination front and back intensity ratio

Component dechlorination front and back intensity ratio is corroded in 2 example 1-3 of table

Group number	Example 1	Example 2	Example 3
				Intensity ratio	1.01	1.02	0.99

(note: dechlorination front and back intensity ratio refers to: concrete test block intensity is divided by dechlorination after application improved method of the present invention dechlorination Preceding concrete test block intensity)

As can be seen from Table 1 and Table 2: prefabricated high conductivity magnesium phosphate cement mortar bars are placed in Corrosion Reinforcement coagulation Native component extracts the high-efficient of chloride ion as anode, and corrodes the strength on concrete material of component after extracting and dechlorinate preceding mixed Solidifying soil material intensity is almost equal, does not influence durability and the safety of structure, has broad application prospects.