CN108205046A - A kind of evaluation method of cement-based material chloride binding stability - Google Patents
A kind of evaluation method of cement-based material chloride binding stability Download PDFInfo
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Abstract
The invention belongs to building materials test technical fields, disclose a kind of evaluation method of cement-based material chloride binding stability.Cement-based material sample broke to be measured, drying are placed on Cl‑The NaCl NaOH that a concentration of 0.7mol/L, pH are 13.3 are simulated to be impregnated in hole solution, until reaching chlorion adsorption equilibrium, sample and drying are taken out after filtering；It is then respectively adding the NaOH HNO that pH value is 13.3,9.0,8.0,4.0,1.03Cl is dipped in desorption solution‑Concentration balance, filtering, Cl in each filtrate is measured using potentiometric titrimeter respectively‑Content is desorbed Cl in solution by different pH value‑Various hydrated products are to Cl in concentration evaluation cement-based material‑Combination stability.The evaluation method of the present invention is similar to practical Service Environment, and test accuracy is high.
Description
Technical field
The invention belongs to building materials test technical fields, and in particular to a kind of cement-based material chloride binding stability is commented
Valency method.
Background technology
At present, it is paid more and more attention the problem of reinforced concrete structure durability.Caused by numerous studies show chlorion
Steel bar corrosion is the major reason that reinforced concrete structure is caused to fail, and armored concrete is usually the knot of concrete package reinforcing bar
Structure, the chlorion in external environment are gradually inwardly spread with hole by the crack of cement-based material and are gathered in rebar surface,
When the chlorion for being diffused into rebar surface reaches a certain concentration, the protective layer of reinforcing bar destroys, and causes steel bar corrosion, and raw
Make cement-based material cracking destruction into dilatancy product.
During cement-based material internal migration, part chlorion is adsorbed by hydrolysis product of cement, no longer to moving to the interior
It moves.This part chlorion be referred to as combine chlorion, because the mode difference combined with hydrolysis product of cement be divided into physical absorption and
Two kinds of chemosetting.It improves and combines amount of chloride ions, it is possible to reduce continue the free chloride ion migrated to rebar surface, help to push away
Slow rebar surface reaches the time of critical concentration, so as to improve reinforced concrete structure durability.However decline in environment pH
In the case of, hydrated product and combine the product of chlorion and can decompose, and with reference to chlorion can also be again transformed into from
By chlorion, Chloride Attack effect is accelerated.
Typically now using water soluble method and acid extracting (JTJ270-98《Marine traffic engineering concrete test regulation》) to cement base
Chlorion existence form and content are tested in material.Containing for total chloridion in cement-based material can be measured using acid extracting
Amount, water soluble method measure the chloride ion content of physical absorption, and the difference of the two is to be chemically combined chloride ion content.Two methods knot
Close the contribution used and characterize physical absorption and chemosetting to cement-based material combination chlorion energy, showing of result of study
It learns combination stability and is better than physical absorption, the chloride binding of cement-based material is also tentatively reflected by acid extracting and water soluble method
Stability.
But current methods Shortcomings, in acid extracting for sample dissolution be a concentration of 6mol/L nitric acid, pH value
Less than 1, so harsh Service Environment will not be faced substantially in actual use in cement-based material.Therefore, using acid
The free chloride ion content discharged again can be over-evaluated during the stability of molten method evaluating chemical curing of chloride ion, is mixed so as to cause reinforcing bar
Xtah Crude Clay structure service life predicted value is relatively low.In addition, cement-based material is generally strong basicity, only with strong acid environment to its chlorine from
Sub- combination stability carries out evaluation and lacks science, can not reflect the correspondence of chloride binding stability and Service Environment.
Chloride binding stability directly determines the content of free chloride ion in cement-based material, is related to chlorion and exists
Migration and the prediction of concrete service life in concrete, thus it is a kind of similar to practical Service Environment there is an urgent need to establish
And can reflect with the corresponding cement-based material chloride binding method for estimating stability of Service Environment.
Invention content
In place of above shortcoming and defect of the existing technology, the purpose of the present invention is to provide a kind of cement matrixs
Expect the evaluation method of chloride binding stability.This method has considered the Service Environment of cement-based material, more scientifically
Evaluate the correspondence of chloride binding stability and environmental pH.
The object of the invention is achieved through the following technical solutions：
A kind of evaluation method of cement-based material chloride binding stability, includes the following steps：
(1) cement-based material sample broke to be measured, drying are placed on Cl-A concentration of 0.7mol/L, pH are 13.3
It is impregnated in NaCl-NaOH simulation hole solutions, until reaching chlorion adsorption equilibrium, sample and drying is taken out after filtering；
(2) by step (1) dried sample be added separately to after crushed pH value be respectively 13.3 ± 0.1,9.0 ±
0.1st, 8.0 ± 0.1,4.0 ± 0.1,1.0 ± 0.1 NaOH-HNO3It is desorbed in solution, is dipped to Cl-Concentration balance, filtering, is adopted
Measure Cl in each filtrate respectively with potentiometric titrimeter-Content is desorbed Cl in solution by different pH value-Concentration evaluates cement matrix
Various hydrated products are to Cl in material-Combination stability.
Further, cement-based material described in step (1) refers to cement slurry, mortar or concrete.
Further, it is crushed described in step (1) and refers to be crushed to 0.63~2mm particles, the drying refers to 25 ± 1
Constant weight is dried under vacuum at DEG C, then sample is placed in the drier of soda lime and silica gel, sample is prevented to be carbonized.
Further, it is crushed described in step (2) and refers to grind to by 160 mesh square hole screens.
Further, described in step (2) Cl in solution is desorbed by different pH value-It is each in concentration evaluation cement-based material
Kind hydrated product is to Cl-The detailed process of combination stability be：PH value is 13.3 ± 0.1 NaOH-HNO3Solution is desorbed to impregnate
The Cl of dissolution-Amount is regarded as the Cl of hydrated product physical absorption-Amount；PH value is mainly calcium hydroxide in the range of 9.0~13.3
It decomposes, the Cl dissolved out in the range of this-Amount is regarded as Ca (OH)2To Cl-Binding capacity；PH in the range of 8.0~9.0 mainly
Friedel salt decomposes, the Cl dissolved out in the range of this-Measure is Friedel salt to Cl-Binding capacity；PH is main in the range of 4.0~8.0
It is C-S-H gel decompositions, the Cl dissolved out in the range of this-Measure is C-S-H gels to Cl-Binding capacity；PH is in the range of 13.3~1.0
The Cl of dissolution-Measure is hydrated product to Cl-With reference to total amount.
The evaluation method of the present invention has the following advantages that and advantageous effect：
(1) compared to conventional test methodologies, evaluation method of the invention is similar to practical Service Environment, and can reflect and take
Use as a servant the corresponding cement-based material chloride binding stability of environment.
(2) present invention proposes that the chlorion curing degree in different pH environments is steady to the combination of chlorion in cement-based material
It is qualitative to be evaluated, the relationship of cement-based material combined chloride ion stability and environment is established, while using constant-current titration
Mode reduces manual operation error, improves test accuracy.
Specific embodiment
With reference to embodiment, the present invention is described in further detail, but the implementation of the present invention is not limited to this.
Embodiment
A kind of evaluation method of cement-based material chloride binding stability of the present embodiment, is as follows：
(1) the net slurry samples of slag cements after conserving 28 days are crushed to the particle of about 2mm, and the vacuum at 25 ± 1 DEG C
Drying is placed in constant weight, then by sample in the drier of soda lime and silica gel, and sample is prevented to be carbonized；Weigh about 125g slag water
Cement paste particle (is accurate to 0.1mg), is soaked in the Cl of 500mL-A concentration of 0.7mol/L, pH are 13.3 NaCl-NaOH
In solution, soaking time 28 days is to reach chlorion adsorption equilibrium；The sample that filtering is up to adsorption equilibrium takes out, and 25 ±
Constant weight is dried under vacuum at 1 DEG C, then sample is placed in the drier of soda lime and silica gel, sample is prevented to be carbonized.
(2) drying sample for being up to adsorption equilibrium by hand with agate mortar is ground to all through 160 mesh square hole screens, is claimed
Taking 15g powder samples, (quality m) is placed in conical flask, and the hydrogen-oxygen that 100mL pH are 13.3 is then accurately measured with volumetric flask
Change sodium solution and pour into flask, be standing and soak for for 24 hours after acutely vibrating 2min, filter suspension with filter paper, accurately measure certain volume
Filtrate (Vf) and chloride ion content (n in filtrate is measured using potentiometric titrimeterf)。
(3) NaOH-HNO of 100mL differences pH value (i=9,8,4,1) is accurately measured respectively with volumetric flask3It is desorbed solution,
It pours into and (in the conical flask of quality m), covers bottle stopper equipped with 15g powder samples to prevent from evaporating, while vibrate for 24 hours, with filter
Paper filters suspension, accurate to measure certain volume filtrate (Vi) and chloride ion content (n in filtrate is measured using potentiometric titrimeteri,i
=9,8,4,1)；Pass through Cl in different desorption solution-Various hydrated products are to Cl in concentration evaluation cement-based material-Combination it is steady
It is qualitative.Specific evaluation procedure is as follows：
1st, the NaOH that pH value is 13.3 in step (2) is desorbed the Cl that solution impregnates dissolution-Amount is regarded as hydrated product object
Manage the Cl of absorption-Water soluble chloride ion content is considered as the content C of physical adsorption chloride ion in cement-based material by amountp, then：
Wherein, CpFor physical adsorption chloride ion content (mg/g) in cement-based material；MClFor the atomicity of chlorine, take
35.45g/mol。
2nd, the total stripping quantity C of cement-based material chlorion under different pH environmentsTiFor：
Wherein, CTiWhen for pH being i, the total stripping quantity of cement-based material chlorion (mg/g).
3rd, cement-based material chemical bonding chloride ion content C under different pH environmentsCiFor：
CCi=CTi-Cp,
Wherein, CCiWhen for pH being i, cement-based material chemical bonding chloride ion content (mg/g).
4th, cement-based material chemical bonding the ratio between chloride ion content and total stripping quantity under different pH environments are defined as pH
The chlorion curing degree BR of cement-based material during for ii(%), i.e.,：
During cement-based material chloride binding estimation of stability, chlorion curing degree is higher to illustrate chloride binding
It is more stable.
Pass throughThe chlorion curing degree that slag cements is starched only when pH is i can be calculated.According to this
The method of embodiment sets 4 groups of experiments, and evaluation result is as shown in table 1.
1 embodiment experiment parameter of table
Above-described embodiment is the preferable embodiment of the present invention, but embodiments of the present invention are not by above-described embodiment
Limitation, other any Spirit Essences without departing from the present invention with made under principle change, modification, replacement, combine, simplification,
Equivalent substitute mode is should be, is included within protection scope of the present invention.
Claims (5)
1. a kind of evaluation method of cement-based material chloride binding stability, it is characterised in that include the following steps：
(1) cement-based material sample broke to be measured, drying are placed on Cl-A concentration of 0.7mol/L, pH are 13.3 NaCl-
It is impregnated in NaOH simulation hole solutions, until reaching chlorion adsorption equilibrium, sample and drying is taken out after filtering；
(2) by step (1) dried sample be added separately to after crushed pH value be respectively 13.3 ± 0.1,9.0 ± 0.1,
8.0 ± 0.1,4.0 ± 0.1,1.0 ± 0.1 NaOH-HNO3It is desorbed in solution, is dipped to Cl-Concentration balance, filtering, using electricity
Position titrator measures Cl in each filtrate respectively-Content is desorbed Cl in solution by different pH value-In concentration evaluation cement-based material
Various hydrated products are to Cl-Combination stability.
2. a kind of evaluation method of cement-based material chloride binding stability according to claim 1, it is characterised in that：
Cement-based material refers to cement slurry, mortar or concrete described in step (1).
3. a kind of evaluation method of cement-based material chloride binding stability according to claim 1, it is characterised in that：
It is crushed described in step (1) and refers to be crushed to 0.63~2mm particles, the drying refers to be dried under vacuum to perseverance at 25 ± 1 DEG C
Weight, then sample is placed in the drier of soda lime and silica gel, sample is prevented to be carbonized.
4. a kind of evaluation method of cement-based material chloride binding stability according to claim 1, it is characterised in that：
It is crushed described in step (2) and refers to grind to by 160 mesh square hole screens.
5. a kind of evaluation method of cement-based material chloride binding stability according to claim 1, it is characterised in that：
Described in step (2) Cl in solution is desorbed by different pH value-Various hydrated products are to Cl in concentration evaluation cement-based material-'s
The detailed process of combination stability is：PH value is 13.3 ± 0.1 NaOH-HNO3It is desorbed the Cl that solution impregnates dissolution-It measures as aquation
The Cl of product physical absorption-Amount；The Cl that pH value dissolves out in the range of 9.0~13.3-It measures as Ca (OH)2To Cl-Binding capacity；PH exists
The Cl dissolved out in the range of 8.0~9.0-Measure is Friedel salt to Cl-Binding capacity；The Cl that pH is dissolved out in the range of 4.0~8.0-Amount
It is C-S-H gels to Cl-Binding capacity；The Cl that pH is dissolved out in the range of 13.3~1.0-Measure is hydrated product to Cl-With reference to total amount.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108827989A (en) * | 2018-06-29 | 2018-11-16 | 山东大学 | A kind of method that C-S-H gel adsorption combination chloride ion accounts for total binding chloride ion ratio in measurement cement paste |
| CN109827881A (en) * | 2019-02-26 | 2019-05-31 | 西南石油大学 | Rock hydration degree characterizing method and system |
| CN110133175A (en) * | 2019-05-07 | 2019-08-16 | 山东大学 | The method of chloride ion content is combined under a kind of accurate Characterization difference carbonizing degree in cement slurry |
| CN114894873A (en) * | 2022-04-13 | 2022-08-12 | 华南理工大学 | Chloride ion sensing electrode and preparation method and application thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103926300A (en) * | 2014-04-09 | 2014-07-16 | 北京工业大学 | Improved method for determining free chlorine ions in cement paste or mortar |
| CN106802318A (en) * | 2017-01-09 | 2017-06-06 | 北京工业大学 | A kind of assay method of hydrated cement paste chlorion fixed amount |
| CN106872641A (en) * | 2017-04-10 | 2017-06-20 | 东南大学 | A kind of cement-based material chloride binding amount method for measuring |
-
2018
- 2018-03-20 CN CN201810228573.8A patent/CN108205046B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103926300A (en) * | 2014-04-09 | 2014-07-16 | 北京工业大学 | Improved method for determining free chlorine ions in cement paste or mortar |
| CN106802318A (en) * | 2017-01-09 | 2017-06-06 | 北京工业大学 | A kind of assay method of hydrated cement paste chlorion fixed amount |
| CN106872641A (en) * | 2017-04-10 | 2017-06-20 | 东南大学 | A kind of cement-based material chloride binding amount method for measuring |
Non-Patent Citations (2)
| Title |
|---|
| 勾密峰等: "矿渣对氯离子的固化作用", 《材料导报Ｂ 研究篇》 * |
| 张会霞: "石墨烯水泥基复合材料吸附性能研究", 《中国优秀硕士学位论文全文数据库（电子期刊）》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108827989A (en) * | 2018-06-29 | 2018-11-16 | 山东大学 | A kind of method that C-S-H gel adsorption combination chloride ion accounts for total binding chloride ion ratio in measurement cement paste |
| WO2020000757A1 (en) * | 2018-06-29 | 2020-01-02 | 山东大学 | Method for measuring ratio of c-s-h gel adsorption combined chloride ion to total combined chloride ion in cement paste |
| CN109827881A (en) * | 2019-02-26 | 2019-05-31 | 西南石油大学 | Rock hydration degree characterizing method and system |
| CN109827881B (en) * | 2019-02-26 | 2022-05-31 | 西南石油大学 | Rock hydration degree characterization method and system |
| CN110133175A (en) * | 2019-05-07 | 2019-08-16 | 山东大学 | The method of chloride ion content is combined under a kind of accurate Characterization difference carbonizing degree in cement slurry |
| CN114894873A (en) * | 2022-04-13 | 2022-08-12 | 华南理工大学 | Chloride ion sensing electrode and preparation method and application thereof |
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