CN117868083A - Method for preventing and treating sulfate erosion disease of railway roadbed - Google Patents
Method for preventing and treating sulfate erosion disease of railway roadbed Download PDFInfo
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- CN117868083A CN117868083A CN202410059202.7A CN202410059202A CN117868083A CN 117868083 A CN117868083 A CN 117868083A CN 202410059202 A CN202410059202 A CN 202410059202A CN 117868083 A CN117868083 A CN 117868083A
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- 208000037265 diseases, disorders, signs and symptoms Diseases 0.000 title claims abstract description 117
- 201000010099 disease Diseases 0.000 title claims abstract description 116
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 title claims abstract description 81
- 238000000034 method Methods 0.000 title claims abstract description 56
- 230000003628 erosive effect Effects 0.000 title claims abstract description 43
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims abstract description 137
- 239000000654 additive Substances 0.000 claims abstract description 95
- 229910002092 carbon dioxide Inorganic materials 0.000 claims abstract description 68
- 239000001569 carbon dioxide Substances 0.000 claims abstract description 67
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 49
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- 239000003795 chemical substances by application Substances 0.000 claims abstract description 24
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- SVPXDRXYRYOSEX-UHFFFAOYSA-N bentoquatam Chemical compound O.O=[Si]=O.O=[Al]O[Al]=O SVPXDRXYRYOSEX-UHFFFAOYSA-N 0.000 claims abstract description 7
- 229910021536 Zeolite Inorganic materials 0.000 claims abstract description 4
- SHFGJEQAOUMGJM-UHFFFAOYSA-N dialuminum dipotassium disodium dioxosilane iron(3+) oxocalcium oxomagnesium oxygen(2-) Chemical compound [O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[Na+].[Na+].[Al+3].[Al+3].[K+].[K+].[Fe+3].[Fe+3].O=[Mg].O=[Ca].O=[Si]=O SHFGJEQAOUMGJM-UHFFFAOYSA-N 0.000 claims abstract description 4
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 claims abstract description 4
- 239000010451 perlite Substances 0.000 claims abstract description 4
- 235000019362 perlite Nutrition 0.000 claims abstract description 4
- 239000008262 pumice Substances 0.000 claims abstract description 4
- 239000010457 zeolite Substances 0.000 claims abstract description 4
- 230000000996 additive effect Effects 0.000 claims description 84
- 229910001653 ettringite Inorganic materials 0.000 claims description 58
- 239000000047 product Substances 0.000 claims description 55
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 claims description 52
- 239000011148 porous material Substances 0.000 claims description 46
- OSGAYBCDTDRGGQ-UHFFFAOYSA-L calcium sulfate Chemical compound [Ca+2].[O-]S([O-])(=O)=O OSGAYBCDTDRGGQ-UHFFFAOYSA-L 0.000 claims description 40
- HOOWDPSAHIOHCC-UHFFFAOYSA-N dialuminum tricalcium oxygen(2-) Chemical compound [O--].[O--].[O--].[O--].[O--].[O--].[Al+3].[Al+3].[Ca++].[Ca++].[Ca++] HOOWDPSAHIOHCC-UHFFFAOYSA-N 0.000 claims description 36
- 238000006243 chemical reaction Methods 0.000 claims description 34
- 238000005067 remediation Methods 0.000 claims description 34
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 claims description 31
- 239000000920 calcium hydroxide Substances 0.000 claims description 31
- 229910001861 calcium hydroxide Inorganic materials 0.000 claims description 31
- 239000004568 cement Substances 0.000 claims description 30
- 229910000019 calcium carbonate Inorganic materials 0.000 claims description 26
- 239000002245 particle Substances 0.000 claims description 21
- 230000000694 effects Effects 0.000 claims description 17
- 239000007921 spray Substances 0.000 claims description 17
- YQCIWBXEVYWRCW-UHFFFAOYSA-N methane;sulfane Chemical compound C.S YQCIWBXEVYWRCW-UHFFFAOYSA-N 0.000 claims description 15
- 230000002265 prevention Effects 0.000 claims description 15
- 238000005070 sampling Methods 0.000 claims description 13
- 239000010456 wollastonite Substances 0.000 claims description 11
- 229910052882 wollastonite Inorganic materials 0.000 claims description 11
- 238000001514 detection method Methods 0.000 claims description 10
- 241000209094 Oryza Species 0.000 claims description 9
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- 229910004298 SiO 2 Inorganic materials 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- MKTRXTLKNXLULX-UHFFFAOYSA-P pentacalcium;dioxido(oxo)silane;hydron;tetrahydrate Chemical compound [H+].[H+].O.O.O.O.[Ca+2].[Ca+2].[Ca+2].[Ca+2].[Ca+2].[O-][Si]([O-])=O.[O-][Si]([O-])=O.[O-][Si]([O-])=O.[O-][Si]([O-])=O.[O-][Si]([O-])=O.[O-][Si]([O-])=O MKTRXTLKNXLULX-UHFFFAOYSA-P 0.000 description 4
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- NNMHYFLPFNGQFZ-UHFFFAOYSA-M sodium polyacrylate Chemical compound [Na+].[O-]C(=O)C=C NNMHYFLPFNGQFZ-UHFFFAOYSA-M 0.000 description 2
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- GVXIVWJIJSNCJO-UHFFFAOYSA-L aluminum;calcium;sulfate Chemical compound [Al+3].[Ca+2].[O-]S([O-])(=O)=O GVXIVWJIJSNCJO-UHFFFAOYSA-L 0.000 description 1
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- GUJOJGAPFQRJSV-UHFFFAOYSA-N dialuminum;dioxosilane;oxygen(2-);hydrate Chemical compound O.[O-2].[O-2].[O-2].[Al+3].[Al+3].O=[Si]=O.O=[Si]=O.O=[Si]=O.O=[Si]=O GUJOJGAPFQRJSV-UHFFFAOYSA-N 0.000 description 1
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Landscapes
- Road Paving Structures (AREA)
Abstract
The invention discloses a method for preventing and treating sulfate erosion diseases of railway roadbed, which comprises the following steps of: 0.2-10 parts of water retention agent and 100 parts of water, and carbon dioxide gas with the saturation amount of 60-100% is filled in the water retention agent; the water-retaining agent is one or more of water-absorbing resin, rice hull ash, expanded shale, pumice, zeolite, perlite and bentonite; s1, spraying additives on the side surfaces of two sides of a railway subgrade; s2, layering, punching and introducing additives into the roadbed of the transition section; s3, quality improvement assessment. According to the method, for the part where sulfate erosion arch disease has occurred, the further development of the disease is prevented by removing the expansion product which causes the disease; for the parts where sulfate erosion and arching diseases do not occur, blocking the possibility of occurrence of diseases from the source by removing reactants generating expansion products; the roadbed section with diseases does not need to be excavated, and the fund, time and social cost caused by disease treatment are obviously reduced.
Description
Technical Field
The invention relates to the technical field of railway roadbed engineering, in particular to a method for preventing/treating sulfate erosion diseases of a railway roadbed.
Background
The railway roadbed transition section is a section which needs special treatment when roadbed is connected with structures and the like, such as a transition area of connection positions of embankment and bridge abutment, embankment and transverse structures, embankment and cutting, cutting and tunnel and the like; the transition section is arranged to enable the rigidity of the track to be gradually changed, reduce the sedimentation difference to the greatest extent, and achieve the purposes of reducing the vibration of the train and the line, slowing down the deformation of the roadbed structure and ensuring the safe, stable and comfortable running of the train. The transition section of the railway subgrade is usually built by cement graded broken stone, is prepared by dry mixing and water adding and mixing cement and graded broken stone meeting the standard requirements, mainly plays a role in rigidity transition between different sections (bridges, tunnels and roads), and is an important guarantee for stable train running.
In recent years, the problem of arch deformation of the high-speed railway roadbed is quite remarkable, and particularly the problem of arch deformation of the roadbed transition section caused by sulfate erosion is increasingly serious. The sulfate attack problem of cement graded crushed stone can be classified into two types, i.e., endogenous sulfate attack and exogenous sulfate attack, depending on the source of the sulfate: (1) The endogenous sulfate erosion mainly refers to the use of cement or graded broken stone with exceeding sulfate content in the preparation of cement graded broken stone, so that a large amount of sulfate is directly introducedInside the cement graded broken stone material, the sulfate further reacts with cement in the cement graded broken stone and hydration reaction products thereof to generate an expansive product (mainly ettringite, a colorless to yellow calcium aluminum sulfate mineral with a chemical molecule of 3CaO.Al) 2 O 3 ·3CaSO 4 ·32H 2 O, wherein the amount of crystallization water is related to the environment), causes a volume expansion, eventually leading to arching of the subgrade. (2) The exogenous sulfate erosion mainly means that a large amount of sulfate exists in the environment (water and soil) where the roadbed transition section is located, and the sulfate contacts cement graded broken stone under the medium action of water, reacts with cement in the cement graded broken stone and hydration reaction products thereof to generate expansive substances (mainly ettringite), so that volume expansion is caused, and finally, the roadbed is arched.
The arch-up disease caused by sulfate erosion has the characteristics of hidden position, slow development and irreversible reaction, so that the arch-up disease becomes a durable railway roadbed which is unpredictable in advance and extremely difficult to treat in the post-treatment. The high-speed rail has strict requirements on the upward arch deformation of the roadbed, and is difficult to directly distinguish by naked eyes. Under normal conditions, the rail car running on the rail detects deformation of the rail surface, then comprehensive factors are judged to be caused by reaction inside the roadbed, and then the roadbed is tested by on-site drilling sampling and laboratory detection, so that the fact that the sulfate content exceeds the standard is verified, and finally the roadbed is judged to be arched due to sulfate erosion.
The existing method for remedying the diseases only has the steps of completely digging out the upper arch road base and re-filling the roadbed, has extremely high capital and time cost, influences the normal and safe operation of the railway, and has huge social cost. Therefore, a method for remedying the cement graded broken stone sulfate erosion disease of the transition section of the railway subgrade, which is simple and convenient to operate, low in cost and capable of preventing the further development of the disease, is urgently needed to be developed.
Disclosure of Invention
The invention aims to solve the problems and provide a method for preventing and treating the sulfate erosion diseases of the railway roadbed, which is simple and convenient to operate, low in cost and capable of preventing the diseases from further developing.
In order to achieve the purpose, the invention adopts the following technical scheme:
the method for preventing and treating sulfate erosion disease of railway roadbed comprises preparing additive according to the amount of 124-6500L additive used per cubic roadbed, spraying additive on the slope surfaces of two sides of roadbed section to be treated, and applying additive to the interior of roadbed;
the additive comprises the following components in parts by weight: 0.2 to 10 parts of water retention agent and 100 parts of water, and is filled with carbon dioxide gas with saturation amount of 60 to 100% (preferably 70 to 100%, 80 to 100% or 90 to 100%); the water-retaining agent is one or a mixture of more of water-absorbing resin, rice hull ash, expanded shale, pumice, zeolite, perlite and bentonite;
the method comprises the following steps:
s1, spraying additive on side surfaces of two sides of railway roadbed
Taking 20-45% of the prepared additive for spraying the surfaces of slope surfaces on two sides of the roadbed;
s2, layering, punching and introducing additive into roadbed of transition section
Drilling holes on the side slope of the roadbed, wherein the pore channels horizontally extend into the roadbed, and the diameter of the horizontal pore channels is 5-15 cm; the distance between any two adjacent pore channels is not less than 1m, and the number of holes of each cubic meter roadbed is not more than 1; after the punching is completed, cleaning the inside of the pore canal, and removing waste residues from the pore canal;
the method comprises the steps of taking a spray pipe, connecting the spray pipe with a spray device through a pipeline, extending the spray pipe into a horizontal pore channel, and uniformly spraying the rest additives into the pore channel through the spray device;
s3, quality assessment of remediation
The quality of the treatment is evaluated by the method of S3.1 and/or S3.2:
s3.1, CO in horizontal duct 2 Concentration detection
Detection of CO in horizontal tunnels prior to remediation 2 The concentration of CO in the horizontal pore canal is detected again 1-10 days after the additive is sprayed for the first time 2 Concentration, if CO in the horizontal channel is detected 2 The concentration is not greatly different from the concentration before the renovation, the additive is applied again and the CO in the horizontal pore canal is detected again after 1 to 10 days 2 Concentration of CO in horizontal pore canal 2 The concentration is higher than the concentration before the treatment;
s3.2, detecting components of roadbed samples after remediation
Sampling the road base after finishing the remediation operation for 1-10 days, carrying out component analysis on the sample, detecting whether the sample still contains sulfate erosion products or can generate substrates of the sulfate erosion products, and if the target substances are still detected, carrying out remediation again until the diseases are eliminated;
the sulfate attack product comprises ettringite, carbonothiosite;
the substrate comprises tricalcium aluminate and calcium hydroxide.
Wherein, the usage amount of the additive per cubic roadbed is calculated by adopting a formula (1):
in the formula (1), m is the mass Kg of cement used per cubic transition section, and w is the mass percentage of tricalcium aluminate contained in the cement.
Preferably, in the step S1, the surface of the slope surface of the side surface of the roadbed is sprayed for a plurality of times, the surface is wetted after each spraying is finished, and the spraying is carried out again after the sprayed additive gradually permeates into the roadbed;
the interval between any two adjacent horizontal pore channels in the step S2 is 1-3 m; the depth of the horizontal pore canal reaches the position where sulfate erosion occurs in the roadbed.
The diagnosis method for the roadbed sulfate erosion disease condition comprises the following steps: and (3) drilling and sampling on the side surface of the roadbed, and carrying out component analysis, wherein if the result shows that the sample contains ettringite and/or other sulfate erosion products, the roadbed section has sulfate erosion diseases, and reinforcing treatment is needed.
In the technical scheme, when the roadbed is sampled, holes are punched inwards from the surfaces of two sides of the roadbed, and the punching depth is not less than 10cm; the method for analyzing the components of the roadbed sample comprises the following steps: and (5) performing X-ray diffraction analysis.
The relative humidity of the environment triggering the water-retaining agent to release water outwards is not lower than 40%, and the environment triggering the water-retaining agent can exist in acidic and alkaline solutions stably; preferably, the water-retaining agent is selected from water-absorbing resin, rice hull ash and bentonite;
the particle size of the water-retaining agent particles is 0.04-1 mm, preferably 0.04-0.08 mm or 0.5-0.9 mm; the water-retaining agent is used in an amount of 1-10 parts or 3-8 parts or 5-10 parts by weight based on 100 parts of water.
The preparation method of the water-retaining agent comprises the following steps:
(1) Weighing water retention agent and water according to the amount, adding the water retention agent and the water into a reaction tank for mixing, and continuously stirring until water retention particles fully absorb water;
(2) And (3) connecting the carbon dioxide gas cylinder, the carbon dioxide bubble generator and the reaction tank in sequence through pipelines, opening a valve on the carbon dioxide gas cylinder and starting the carbon dioxide bubble generator to enable a large amount of carbon dioxide bubbles to be filled into the reaction tank prepared in the step (1), and continuously filling the carbon dioxide bubbles into the reaction tank until the carbon dioxide content in water is saturated.
Whether the carbon dioxide gas content reaches saturation or not can be judged by any one of the following methods:
(1) the saturation of the charged carbon dioxide can be judged by observing the state of the solution: the whole liquid is white, instead of only the vicinity of the inflation tube becoming white, and bubbles formed by newly inflated gas float on the water surface to be broken, so that obvious phenomenon of large-scale breaking of bubbles on the water surface occurs;
(2) the liquid pH was no longer reduced while maintaining continuous carbon dioxide dosing and was maintained for at least 3 minutes, indicating that carbon dioxide dosing had reached a maximum and that additive preparation was complete.
According to experiments, the time required for filling carbon dioxide into the reaction tank until the carbon dioxide is saturated is 10-60 min, and the pH value of the additive with saturated carbon dioxide content is less than or equal to 5.4.
In the technical scheme, 1000-6300 liters of additive, preferably 1400-6000 liters or 1400-3000 liters, are used for spraying the surface of the slope surfaces on two sides of the roadbed, and the rest is used for being applied in the horizontal pore canal; preferably, the additive is applied once in total and the quality of the treatment is assessed 3 to 7 days or 5 to 7 days after the additive application is completed.
In the step S3.2, the contents of ettringite, carbon sulfur wollastonite, tricalcium aluminate, calcium hydroxide, calcium sulfate and calcium carbonate in the sample are detected to judge the quality of disease treatment, and the judging method comprises the following steps:
(1) For the areas where diseases and deformation occur, (1) if ettringite or carbosulfatoxite is detected in the sample and tricalcium aluminate and calcium hydroxide are contained, the disease products are not cleaned, and the diseases are further developed possibly, and the disease needs to be continuously cured; (2) if ettringite or carbonthiotobermorite is detected in the sample, but no tricalcium aluminate or calcium hydroxide is contained, the disease products are not cleaned, but the disease cannot further develop due to no reactant, and the disease products need to be continuously remedied to be completely cleaned; (3) if the sample does not contain ettringite and carbosulfatobermorite, does not contain tricalcium aluminate and calcium hydroxide and contains a large amount of calcium sulfate and calcium carbonate, the sample shows that all disease products are removed, and no reactant capable of reacting to generate the disease products exists, so that the treatment effect is good; (4) if the sample does not contain ettringite and carbosulfatobermorite, but contains tricalcium aluminate, calcium hydroxide, calcium sulfate and calcium carbonate, the sample shows that all disease products are removed, but the possibility of sulfate attack disease still exists in the future, and the measures of the application should be continuously developed to remedy the disease;
(2) For areas where no disease occurs or where disease occurs but there is no deformation: (1) if the sample does not contain ettringite and carbosulfatobermorite, does not contain tricalcium aluminate and calcium hydroxide and contains a large amount of calcium sulfate and calcium carbonate, the prevention effect is good, and the possibility of diseases in the future is low; (2) if the sample does not contain ettringite and carbosulfatobermorite, but contains tricalcium aluminate, calcium hydroxide, calcium sulfate and calcium carbonate, the prevention effect is poor, sulfate erosion possibly occurs in the future, and the measures of the application need to be continuously developed for prevention; (3) if ettringite, carbon sulfur wollastonite, tricalcium aluminate, calcium hydroxide, calcium sulfate and calcium carbonate are detected in the sample, the fact that diseases possibly occur in the future is indicated, the quantity of related products in the present stage is insufficient to generate obvious diseases, the prevention effect is poor, and the measures of the application need to be continuously developed for prevention; (4) if ettringite and carbon sulfur wollastonite are detected in the sample, but the sample does not contain tricalcium aluminate and calcium hydroxide, the risk of generating ettringite by continuous reaction is not shown, but the existing ettringite needs to be continuously remedied and eliminated.
The weather conditions applicable to the method of the invention are as follows: the ambient temperature is not lower than 5 ℃ and not higher than 40 ℃, and the relative humidity is not lower than 30%.
The beneficial effects of the invention are as follows:
(1) For the parts where sulfate attack and arching disease occur, the further development of the disease can be prevented by removing the expansion products which cause the disease;
(2) For the parts where sulfate erosion and arching diseases do not occur, the possibility of occurrence of diseases can be blocked from the source by removing reactants generating expansion products;
(3) The roadbed section with diseases does not need to be excavated, and the fund, time and social cost caused by disease treatment are obviously reduced.
Drawings
FIG. 1 is a schematic diagram of the horizontal tunnel perforation locations in a transition section subgrade.
Fig. 2 is an elevation view of a perforated rear side slope of the interior of the transition section subgrade.
Figure 3 shows the XRD results of X-ray diffraction analysis before and after the disease of the roadbed sample in transition section 1.
Figure 4 shows the XRD results of X-ray diffraction analysis before and after the disease of the roadbed sample in transition section No. 2.
Figure 5 shows the XRD results of X-ray diffraction analysis before and after the disease of the roadbed sample in transition section 3.
Detailed Description
The invention is further illustrated, but is not limited, by the following examples.
The experimental methods in the following examples are conventional methods unless otherwise specified.
Example 1 additive for the treatment of sulfate attack disease of railway foundations
1. Additive formulation
The additive for remedying the sulfate erosion disease of the railway subgrade is prepared from gaseous carbon dioxide, water-retaining particles and water. The gaseous carbon dioxide should meet the relevant national standard and should not contain miscellaneous gases which affect the safety and the use effect. The water-retaining particles can be one or more of water-absorbing resin, rice hull ash, expanded shale, pumice, zeolite, perlite, bentonite and the like, have a maximum particle size of not more than 1mm, trigger the environment relative humidity of releasing water to the outside to be not less than 40%, and can exist stably in acidic and alkaline solutions.
The action mechanism of the carbon dioxide which is an effective component participating in chemical reaction in the additive mainly comprises three aspects: in the first aspect, carbon dioxide can react with roadbed expansion products mainly comprising ettringite, and the volume of the ettringite after the ettringite reacts with the carbon dioxide is greatly reduced, so that the expansion caused by the generation of the expansion products is eliminated; in the second aspect, carbon dioxide can also react with cement hydration reaction products, and the cement hydration reaction products are important reactants for generating expansion products, so that the carbon dioxide reacts with the cement hydration reaction products to consume the reactants capable of generating the expansion products, and the possibility of generating the expansion products is eliminated from the source; in a third aspect, unhydrated cement is also an important reactant in the formation of expansion products, with which carbon dioxide can also react to eliminate the possibility of its formation of expansion products. The chemical reaction occurring when the additive of the invention remedies the sulfate attack of the railway roadbed mainly comprises the following steps:
2CaO·SiO 2 +2CO 2 +H 2 O→2CaCO 3 +SiO 2 +H 2 O
3CaO·SiO 2 +3CO 2 +H 2 O→3CaCO 3 +SiO 2 +H 2 O
3CaO·Al 2 O 3 +3CO 2 +4H 2 O→3CaCO 3 +2Al(OH) 3 +H 2 O
Ca(OH) 2 +CO 2 →CaCO 3 +H 2 O
3CaO·Al 2 O 3 ·3CaSO 4 ·32H 2 o (ettringite) +3CO 2 +H 2 O→3CaSO 4 ·2H 2 O+2Al(OH) 3 +3CaCO 3 +H 2 OCaSiO 3 ·CaCO 3 ·CaSO 4 ·15H 2 O (carbon sulfur tobermorite) +CO 2 +H 2 O→CaCO 3 +CaSO 4 +H 2 SiO 3 +H 2 O
Carbon dioxide and roadbed expansion products and other reactants refer to unhydrated cement and products after hydration reaction of the cement, the reaction can only occur under a certain relative humidity environment, but a large number of gaps and pores exist in the cement graded broken stone material, the permeability is good, so that water entering the material can flow away through communicated holes faster, the water in the material is reduced, the relative humidity is reduced, and the efficiency of the reaction of the carbon dioxide is further reduced. Therefore, water should be replenished in the remediation process, the water retention particles can absorb and retain a large amount of water in a short time, and when the external humidity is reduced, the water absorbed in the interior can be released to compensate the external water loss, so that the humidity required by the chemical reaction of carbon dioxide is ensured. And, the use of the water-retaining particles can continuously provide moisture to the interior of the material for a certain period of time, so that the relative humidity of the interior is kept stable. Meanwhile, the particle size of the water-retaining particles is controlled to regulate and control the minimum relative humidity of the environment in which the water-retaining particles begin to release water outwards, so that the relative humidity inside the material is between 50% and 70%, and the relative humidity is in an ideal interval favorable for carbon dioxide reaction.
2. Preparation of additives
The devices required for preparing the additive are a carbon dioxide gas cylinder, a carbon dioxide bubble generator and a reaction tank as a reaction site. The material of the reaction tank can be acid-base corrosion resistant and can bear certain carbon dioxide gas pressure, and plastics such as PP, acid-resistant stainless steel and the like can be adopted.
The preparation of the additive is carried out according to the following steps:
(1) Mixing the water-retaining particles with water in a proportion of 0.2-10% of the water mass in a reaction tank, and continuously stirring for 10-60 min by a stirrer until the water-retaining particles fully absorb water, wherein the stirring function is to prevent the water-retaining particles from agglomerating due to water absorption.
(2) And (2) connecting a carbon dioxide gas cylinder, a carbon dioxide bubble generator and a reaction tank in sequence through pipelines, opening a valve on the carbon dioxide gas cylinder and starting the carbon dioxide bubble generator, so that a large number of carbon dioxide bubbles are filled into the reaction tank body filled with water-retaining particles and water which are fully absorbed in the step (1), and continuously filling the reaction tank body until the carbon dioxide content in the water is saturated. According to the experiment, the pH of the solution is kept constant for at least 3 minutes, which indicates that the carbon dioxide content therein is saturated, and aeration can be stopped. The carbon dioxide bubble generator can adopt a conventional bubble generator purchased in the market, and also can adopt a micro-nano bubble generator, and the micro-nano bubble generator can enable carbon dioxide gas to exist in water in a large amount in the form of nano-sized bubbles so as to improve the carbon dioxide content in the solution, and the gas stably exists for a longer time.
The saturation of the charged carbon dioxide can also be judged by observing the state of the solution: when the carbon dioxide bubble generator charges carbon dioxide gas into the reaction tank, the water becomes white due to the existence of a large number of tiny bubbles, but the bubbles only gather near the gas charging pipe at the beginning. When the carbon dioxide gas filled into the water reaches saturation, the newly filled gas will not be dissolved continuously, and the formed bubbles will float on the water surface directly to be broken, so that obvious phenomenon of large-scale breaking of bubbles on the water surface occurs, and the whole liquid is enabled to be white, namely, the bubbles are fully distributed in the water body, and not only the vicinity of the air charging pipe is whitened. When the carbon dioxide gas content in the water is not saturated, a large amount of carbon dioxide is dissolved, fewer bubbles are broken on the floating water surface, and the solution only turns white near the inflation tube.
Thus, at least two methods may be employed to determine whether it isWhether sufficient carbon dioxide has been charged: one is to stop the aeration when the carbon dioxide filled water is no longer continuously whitened and a large number of bubbles are broken on the water surface; one is that the pH of the liquid is no longer reduced while the carbon dioxide charge is maintained and can be maintained for at least 3 minutes, indicating that the carbon dioxide charge has reached a maximum value and that the preparation of the additive is complete. CO in solution at different temperatures 2 The saturation varies, so that the carbon dioxide content of the prepared additive varies according to weather conditions during construction.
It should be noted that the stability of carbon dioxide bubbles filled in water is not high, the bubbles are extremely easy to break under the influence of external temperature, pressure, vibration and other factors, gas is dissipated, the utilization efficiency of the gas is improved, the disease treatment effect is finally improved, and the prepared additive should be used immediately as much as possible.
3. Additive screening Pre-experiment
Several groups of different additive products in Table 1 were prepared according to the above procedure, and the water-retaining particles used:
sodium polyacrylate (SodiumPolyacrylate, SAP): is a super absorbent resin which can quickly absorb a large amount of water and lock the water in gel;
bentonite: is a nonmetallic mineral product with montmorillonite as the main mineral component;
rice hull ash: the rice hull ash is relatively common solid waste and has a certain application value.
Additive screening pre-experiments: the roadbed sample with sulfate erosion disease is taken, the additive prepared in the table 1 is sprayed, whether the surface salt generated by sulfate erosion on the sample is reduced or not is observed visually after 1 day, and if the reduction can be observed, the additive has an effect.
TABLE 1
Since the rice husk ash has a lower water retention effect than that of resin, and the difference of the internal structures of materials is an inherent property, the parameters of smaller particle size and larger mixing amount are selected for experiments when the rice husk ash is selected as the water retention particles.
CO at normal temperature and pressure 2 The pH of the saturated solution was about 5.6. The pre-experiments of table 1 gave: when the amount of carbon dioxide gas charged reaches the maximum, the pH of the solution is 5.4 or less, and the pH of the solution can be maintained for at least 3 minutes.
Example 2 method for treating sulfate erosion disease of No. 1 transition section of railway subgrade
Railway roadbeds where serious sulfate attack diseases have occurred often become whitish or the arching of the roadbeds can be detected, and a person skilled in the art can judge the road roadbeds accurately and quickly by naked eyes. In general, if sulfate attack damage is found on the surface of the subgrade, sulfate attack also usually occurs inside the subgrade. The presence of sulfate attack products, ettringite, in the sample can be further verified by sampling to a laboratory test.
The method is also suitable for the parts which do not have sulfate attack diseases, and the possibility of the diseases can be blocked from the source by removing reactants.
1. Diagnosis of sulfate attack disease conditions
The side surface of the roadbed of the transition section No. 1 is drilled and deeply penetrates into the surface to be sampled at least 10cm so as to exclude the influence of external environment, the concrete sampling method can refer to the relevant regulations of railway experiments, sampling can be performed at a plurality of positions, and the position near the arch part on the roadbed can be properly encrypted and sampled for a plurality of times. The samples were sent to a laboratory for powder X-ray diffraction analysis XRD (Raman spectroscopy assisted, but not necessarily), and the results (fig. 3) showed that the samples contained significant amounts of sulfate attack products such as ettringite, which were needed for sulfate attack disease remediation.
2. Method of remediation
The additive 1 product of Table 1 was prepared as in example 1 and ready for use.
Suitable environmental conditions for the implementation of the method of the invention are: the temperature is not lower than 5 ℃ and not higher than 40 ℃, and the relative humidity is not lower than 30%; too low a temperature not only affects the activity of the additive to reduce the remediation efficiency, but also may cause the additive to freeze, thereby generating frost heaving damage; too high a temperature releases carbon dioxide too rapidly to be dissipated as soon as the reaction occurs, thereby reducing the reaction degree; the environmental humidity is too low, carbon dioxide cannot participate in the reaction, and the remediation also fails.
The method comprises the following steps:
firstly, estimating the use volume of the additive: the grade of cement used for roadbed in transition section is known, and the type of cement contains tricalcium aluminate (3CaO.Al 2 O 3 ) The mass percent of the additive is known, and the total volume of the additive is calculated by adopting the formula (1):
in the formula (1), m is the mass (unit is Kg) of cement used per cubic transition section, and w is tricalcium aluminate (3CaO.Al) 2 O 3 ) Is a mass percentage of (a). Calculating the required additive amount V of each cubic roadbed transition section according to the content of tricalcium aluminate in cement of various grades at present and the mass of cement which is commonly used for each cubic of cement graded broken stone of the railway roadbed transition section Additive agent 124 to 6245L.
S1, spraying additive on side surfaces of two sides of roadbed of transition section
The additive is sprayed by a spraying device, the surface of the side slope of the transition section is sprayed from top to bottom and from left to right, and the amount of the additive used by the side slope of the transition section is 20-45% of the total volume of the additive. After finishing one spraying task of one spraying surface, suspending for about 10 minutes, and repeating spraying after the sprayed additive gradually permeates into the roadbed, wherein the cycle is carried out for 2-5 times so as to ensure that enough additive can enter the roadbed. It should be noted, however, that the time between sprays should not be too long to prevent the passage of the latter additive after the pores within the road bed cement-graded crushed stone material, which have been wetted by the former additive, have dried. After the spraying task on one height is completed, the next height is developed, and the process is carried out until all spraying operations are completed.
S2, layering, punching and introducing additive into roadbed of transition section
Drilling holes horizontally into the roadbed on the side slope of the roadbed of the transition section, wherein the diameter of a horizontal pore canal is 5-15 cm; the spacing between any two adjacent cells should not be less than 1m, typically 1 to 3m, to minimize the impact of perforation on the overall structure. And each cubic meter of roadbed is perforated by not more than 1.
The depth of the horizontal pore canal is determined according to the actual situation, and the horizontal pore canal can penetrate through the structure or not: if the roadbed sample detection result shows that the roadbed middle part vertical to the center position of the driving direction does not contain sulfate erosion products, a penetrating structure is not needed; if the sample in the middle of the roadbed detects erosion products, the pore canal should penetrate the structure so that the additive can contact the disease position as much as possible. To ensure a healing effect, the horizontal tunnels preferably extend through the roadbed of the transition section.
After the punching is completed, the inside of the hole is cleaned, and the waste residue is removed from the pore canal.
The method comprises the steps of taking a spray pipe, connecting the spray pipe with a spray device through a pipeline, wherein the spray pipe is a long pipe, a plurality of through holes are formed in the pipe wall, extending the spray pipe into a horizontal pore channel, and spraying the rest additives into the pore channel through the spray device.
S3, quality assessment of remediation
The quality of the remediation can be detected by combining two methods, and the CO in the horizontal duct can be detected periodically during the remediation process 2 After the concentration is primarily judged and disease remediation is finished, the road base can be sampled and sent to a laboratory to detect the components so as to finally confirm the remediation quality:
s3.1, CO in horizontal duct 2 Concentration detection
Before, during and after the treatment, the CO in the horizontal pore canal is detected 2 The concentration of CO in the horizontal pore canal is detected again 1-10 days (preferably 3-8 days) after the additive is sprayed for the first time 2 Concentration, if CO in the horizontal channel is detected 2 Concentration and finishingThe concentration difference before treatment is not large, which indicates CO 2 Too much is consumed by reaction or dissipation to the environment, and a higher concentration of CO2 in the subgrade cannot be maintained to play a role in disease control, and the additive should be applied again, so that the process is repeated until the CO in the horizontal pore canal is removed 2 The concentration is higher than before remediation. In this example, CO was again detected in the horizontal tunnel 7 days after the first spraying of the additive 2 The concentration is higher than the concentration before the treatment, and the treatment is judged to be completed without the need of secondary spraying.
S3.2, detecting components of roadbed samples after remediation
After finishing the treatment operation for 1-10 days (preferably 3-8 days), sampling the roadbed, wherein the sampling position is at least 10cm below the surfaces of two sides of the roadbed, sampling at a plurality of positions, encrypting and sampling for a plurality of times at the vicinity of the position where the roadbed is arched, sending the sample to a laboratory for powder X-ray diffraction analysis XRD (Raman spectroscopy can be used for assistance, but not necessary), and detecting the content of ettringite, carbon-sulfur-calcium stone, tricalcium aluminate, calcium hydroxide, calcium sulfate and calcium carbonate in the sample to judge the quality of disease treatment, wherein the judging method is as follows:
(1) For the areas where diseases and deformation occur, (1) if ettringite or carbosulfatoxite is detected in the sample and tricalcium aluminate and calcium hydroxide are contained, the disease products are not cleaned, and the diseases are further developed possibly, and the disease needs to be continuously cured; (2) if ettringite or carbonthiotobermorite is detected in the sample, but no tricalcium aluminate or calcium hydroxide is contained, the disease products are not cleaned, but the disease cannot further develop due to no reactant, and the disease products need to be continuously remedied to be completely cleaned; (3) if the sample does not contain ettringite and carbosulfatobermorite, does not contain tricalcium aluminate and calcium hydroxide and contains a large amount of calcium sulfate and calcium carbonate, the sample shows that all disease products are removed, and no reactant capable of reacting to generate the disease products exists, so that the treatment effect is good; (4) if the sample does not contain ettringite and carbosulfatobermorite, but contains tricalcium aluminate, calcium hydroxide, calcium sulfate and calcium carbonate, all disease products are removed, but the possibility of sulfate attack diseases still exists in the future, and the measures of the application should be continued to be developed for remediation.
(2) For areas where no disease occurs or where disease occurs but there is no deformation, i.e. early in the occurrence of disease, i.e. the accumulation phase of the expansion products, this phase can detect the presence of a certain amount or trace of ettringite, but not the arching up of the subgrade: (1) if the sample does not contain ettringite and carbosulfatobermorite, does not contain tricalcium aluminate and calcium hydroxide and contains a large amount of calcium sulfate and calcium carbonate, the prevention effect is good, and the possibility of diseases in the future is low; (2) if the sample does not contain ettringite and carbosulfatobermorite, but contains tricalcium aluminate, calcium hydroxide, calcium sulfate and calcium carbonate, the prevention effect is poor, sulfate erosion possibly occurs in the future, and the measures of the application need to be continuously developed for prevention; (3) if ettringite, carbon sulfur wollastonite, tricalcium aluminate, calcium hydroxide, calcium sulfate and calcium carbonate are detected in the sample, the fact that diseases possibly occur in the future is indicated, because the quantity of related products in the current stage is insufficient to generate obvious diseases, the prevention effect is poor, and the measures of the application need to be continuously developed for prevention; (4) if ettringite and carbon sulfur wollastonite are detected in the sample, but the sample does not contain tricalcium aluminate and calcium hydroxide, the risk of generating ettringite by continuous reaction is not shown, but the existing ettringite needs to be continuously remedied and eliminated.
In the embodiment, when the section 1 is remedied, the usage amount of the roadbed additive per cubic unit is 1500L, 20% of the roadbed additive is used for spraying the slope surfaces on two sides of the roadbed, and the rest of the roadbed additive is used for spraying in a horizontal pore canal. The distance between every two horizontal pore canals is 2m, and each horizontal pore canal penetrates through the roadbed.
In this example, the additives were applied once in total, and after 7 days from the first spraying of the additives, the roadbed was sampled and sent to a laboratory for component detection, and the contents of ettringite, carbosulfatobermorite, tricalcium aluminate, calcium hydroxide, calcium sulfate, and calcium carbonate in the samples were detected, and the XRD results of powder X-ray diffraction analysis of the samples before and after the remediation were shown in fig. 3: before remediation, the sample contains gypsum that provides sulfate ions for sulfate attack and ettringite that is the reaction product of the sulfate attack. This indicates that sulfate attack has occurred on the sample prior to remediation. After the method is adopted for the treatment, no diffraction peak of ettringite exists in the treated sample, which indicates that ettringite which is an erosion product causing expansion is removed by carbon dioxide reaction; the diffraction peak of calcium carbonate shows that ettringite reacts with carbon dioxide to form calcium carbonate, and the conclusion that ettringite reacts is proved; the unchanged diffraction peak of gypsum is consistent with the fact that gypsum does not react with the additives of the present application. Therefore, the method can eliminate ettringite causing swelling diseases in sulfate attack, thereby achieving the purposes of eliminating disease products and preventing disease development.
Example 3 treatment of sulfate Corrosion disease of section 2 of transition section of railway roadbed
Disease condition diagnosis, disease remediation and remediation quality evaluation were performed on section 2 of the roadbed transition section according to the method in example 2. The additive is additive 5 in table 1.
According to field investigation, the phenomenon of sulfate erosion disease caused by the carbon sulfur tobermorite appears in the transition section No. 2 to a certain extent, the phenomenon is shown that the roadbed cement paste is in a 'mushy' shape, the strength is lost, and according to experience, the sulfate erosion disease is serious in the situation.
In the embodiment, when the No. 2 section is remedied, the usage amount of the roadbed additive per cubic unit is 2500L, 30% of the roadbed additive is used for spraying the slope surfaces on two sides of the roadbed, and the rest of the roadbed additive is used for spraying in a horizontal pore canal. The distance between every two horizontal pore channels is 1m, each horizontal pore channel penetrates through the roadbed, the roadbed is treated once in total, the roadbed is drilled and sampled on the 10 th day after the additive spraying operation is finished, the sample is sent to a laboratory for powder X-ray diffraction analysis XRD, and the contents of ettringite, carbon sulfur wollastonite, tricalcium aluminate, calcium hydroxide, calcium sulfate and calcium carbonate in the sample are detected. The results of sample detection before and after the remediation are shown in fig. 4: before remediation, the sample contained gypsum that provided sulfate ions for sulfate attack and carbazeite that was the reaction product of the sulfate attack. This indicates that sulfate attack has occurred on the sample prior to remediation. According to the method, after treatment, no diffraction peak of the carbonothiosite exists in the sample after the treatment, which indicates that the disease product carbonothiosite is removed by carbon dioxide reaction; the diffraction peak of the calcium carbonate shows that the carbon sulfur tobermorite reacts with the carbon dioxide to form the calcium carbonate, and the conclusion that the carbon sulfur tobermorite reacts is proved; the fact that the gypsum does not react with the additives of the present invention is conformed to the fact that the diffraction peak of gypsum does not change. Therefore, the method can eliminate the sulfate erosion product of the carbazeite, thereby achieving the purpose of preventing the further development of diseases.
Example 4 disease prevention in transition segment No. 3 where sulfate attack disease has not occurred
Disease condition diagnosis, disease remediation and remediation quality evaluation were performed on section 2 of the roadbed transition section according to the method in example 2.
According to field investigation, the transition section No. 3 section does not have the phenomenon of sulfate erosion disease. In this example, the product of additive 3 in Table 1 was used for the conditioning.
In the embodiment, when the section 3 is remedied, the usage amount of the additive per cubic roadbed is 6000L, 40% of the additive is used for spraying the slope surfaces on two sides of the roadbed, and the rest of the additive is used for spraying in a horizontal pore canal. The distance between every two horizontal pore canals is 3m, each horizontal pore canal penetrates through the roadbed, the roadbed is treated once in total, the 10 th day after the additive spraying operation is completed, the roadbed is drilled and sampled, the sample is sent to a laboratory for powder X-ray diffraction analysis XRD, and the detection results of the sample before and after the treatment are shown in fig. 5: before remediation, the sample contained gypsum that provided sulfate ions for sulfate attack, but did not contain ettringite and carbazeite that were the reaction products of sulfate attack. This indicates that the sample before the reconditioning had conditions for sulfate attack, but did not. After the treatment according to the method of the invention is carried out, diffraction peaks of ettringite and carbazeite still do not exist in the sample after the treatment, which indicates that no erosion product exists in the sample; no diffraction peak of calcium carbonate is seen, which confirms that the sample does not contain ettringite and carbon sulfur wollastonite (otherwise, the ettringite and the carbon sulfur wollastonite react with the additive to generate calcium carbonate); the fact that the gypsum does not react with the additives of the present invention is conformed to the fact that the diffraction peak of gypsum does not change.
Claims (10)
1. A method for preventing and treating sulfate erosion disease of railway roadbed is characterized in that,
preparing an additive according to the amount of 124-6500 liters of the additive used for each cubic roadbed, carrying out additive spraying treatment on the slope surfaces on two sides of a roadbed section to be treated, and applying the additive to the interior of the roadbed;
the additive comprises the following components in parts by weight: 0.2-10 parts of water retention agent and 100 parts of water, and carbon dioxide gas with the saturation amount of 60-100% is filled in; the water-retaining agent is one or a mixture of more of water-absorbing resin, rice hull ash, expanded shale, pumice, zeolite, perlite and bentonite;
the method comprises the following steps:
s1, spraying additive on side surfaces of two sides of railway roadbed
Taking 20-45% of the prepared additive for spraying the surfaces of slope surfaces on two sides of the roadbed;
s2, layering, punching and introducing additive into roadbed of transition section
Drilling holes on the side slope of the roadbed, wherein the pore channels horizontally extend into the roadbed, and the diameter of the horizontal pore channels is 5-15 cm; the distance between any two adjacent pore channels is not less than 1m, and the number of holes of each cubic meter roadbed is not more than 1; after the punching is completed, cleaning the inside of the pore canal, and removing waste residues from the pore canal;
the method comprises the steps of taking a spray pipe, connecting the spray pipe with a spray device through a pipeline, extending the spray pipe into a horizontal pore channel, and uniformly spraying the rest additives into the pore channel through the spray device;
s3, quality assessment of remediation
The quality of the treatment is evaluated by the method of S3.1 and/or S3.2:
s3.1, CO in horizontal duct 2 Concentration detection
Detection of CO in horizontal tunnels prior to remediation 2 The concentration of CO in the horizontal pore canal is detected again 1-10 days after the additive is sprayed for the first time 2 Concentration, if CO in the horizontal channel is detected 2 If the concentration is not different from the concentration before the treatment, the additive is applied again and inspected again after 1-10 daysMeasuring CO in horizontal duct 2 Concentration of CO in horizontal pore canal 2 The concentration is higher than the concentration before the treatment;
s3.2, detecting components of roadbed samples after remediation
Sampling the road base after finishing the remediation operation for 1-10 days, carrying out component analysis on the sample, detecting whether the sample still contains sulfate erosion products or can generate substrates of the sulfate erosion products, and if the target substances are still detected, carrying out remediation again until the diseases are eliminated;
the sulfate attack product comprises ettringite, carbonothiosite;
the substrate comprises tricalcium aluminate and calcium hydroxide.
2. The method according to claim 1, characterized in that: the additive usage amount per cubic roadbed is calculated by adopting the formula (1):
in the formula (1), m is the mass Kg of cement used per cubic transition section, and w is the mass percentage of tricalcium aluminate contained in the cement.
3. The method according to claim 1, characterized in that:
in the step S1, spraying and wetting the surface of the slope surface of the side surface of the roadbed for a plurality of times, suspending for 5-15 minutes after each spraying is finished, and spraying again after the sprayed additive gradually permeates into the roadbed;
the interval between any two adjacent horizontal pore channels in the step S2 is 1-3 m; the depth of the horizontal pore canal reaches the position where sulfate erosion occurs in the roadbed.
4. The method according to claim 1, characterized in that: the diagnosis method for the roadbed sulfate erosion disease condition comprises the following steps:
and (3) drilling and sampling on the side surface of the roadbed, and carrying out component analysis, wherein if the result shows that the sample contains ettringite and/or other sulfate erosion products, the roadbed section has sulfate erosion diseases, and reinforcing treatment is needed.
5. The method according to claim 1 or 4, characterized in that: when the roadbed is sampled, inwards punching and sampling are carried out from the surfaces of the two sides of the roadbed, and the punching depth is not less than 10cm; the method for analyzing the components of the roadbed sample comprises the following steps: and (5) performing X-ray diffraction analysis.
6. The method according to claim 1, characterized in that:
the relative humidity of the environment triggering the water-retaining agent to release water outwards is not lower than 40%, and the environment triggering the water-retaining agent can exist in acidic and alkaline solutions stably; preferably, the water-retaining agent is selected from water-absorbing resin, rice hull ash and bentonite;
the particle size of the water-retaining agent particles is 0.04-1 mm, preferably 0.04-0.08 mm or 0.5-0.9 mm; the water-retaining agent is used in an amount of 1-10 parts or 3-8 parts or 5-10 parts by weight based on 100 parts of water.
7. The method according to claim 1 or 6, characterized in that: the preparation method of the water-retaining agent comprises the following steps:
(1) Weighing water retention agent and water according to the amount, adding the water retention agent and the water into a reaction tank for mixing, and continuously stirring until water retention particles fully absorb water;
(2) And (3) connecting the carbon dioxide gas cylinder, the carbon dioxide bubble generator and the reaction tank in sequence through pipelines, opening a valve on the carbon dioxide gas cylinder and starting the carbon dioxide bubble generator to enable a large amount of carbon dioxide bubbles to be filled into the reaction tank prepared in the step (1), and continuously filling the carbon dioxide bubbles into the reaction tank until the carbon dioxide content in water is saturated.
8. The method according to claim 1, characterized in that: 1000-6300 liters of additive is used for each cubic roadbed, preferably 1400-6000 liters or 1400-3000 liters, 20-40% of the prepared additive is used for spraying the surfaces of slopes on two sides of the roadbed, and the rest is used for being applied in a horizontal pore canal; preferably, the additive is applied once in total and the quality of the treatment is assessed 3 to 7 days or 5 to 7 days after the additive application is completed.
9. The method according to claim 1, characterized in that:
in the step S3.2, the contents of ettringite, carbon sulfur wollastonite, tricalcium aluminate, calcium hydroxide, calcium sulfate and calcium carbonate in the sample are detected to judge the quality of disease treatment, and the judging method comprises the following steps:
(1) For the areas where diseases and deformation occur, (1) if ettringite or carbosulfatoxite is detected in the sample and tricalcium aluminate and calcium hydroxide are contained, the disease products are not cleaned, and the diseases are further developed possibly, and the disease needs to be continuously cured; (2) if ettringite or carbonthiotobermorite is detected in the sample, but no tricalcium aluminate or calcium hydroxide is contained, the disease products are not cleaned, but the disease cannot further develop due to no reactant, and the disease products need to be continuously remedied to be completely cleaned; (3) if the sample does not contain ettringite and carbosulfatobermorite, does not contain tricalcium aluminate and calcium hydroxide and contains a large amount of calcium sulfate and calcium carbonate, the sample shows that all disease products are removed, and no reactant capable of reacting to generate the disease products exists, so that the treatment effect is good; (4) if the sample does not contain ettringite and carbosulfatobermorite, but contains tricalcium aluminate, calcium hydroxide, calcium sulfate and calcium carbonate, the sample shows that all disease products are removed, but the possibility of sulfate attack disease still exists in the future, and the measures of the application should be continuously developed to remedy the disease;
(2) For areas where no disease occurs or where disease occurs but there is no deformation: (1) if the sample does not contain ettringite and carbosulfatobermorite, does not contain tricalcium aluminate and calcium hydroxide and contains a large amount of calcium sulfate and calcium carbonate, the prevention effect is good, and the possibility of diseases in the future is low; (2) if the sample does not contain ettringite and carbosulfatobermorite, but contains tricalcium aluminate, calcium hydroxide, calcium sulfate and calcium carbonate, the prevention effect is poor, sulfate erosion possibly occurs in the future, and the measures of the application need to be continuously developed for prevention; (3) if ettringite, carbon sulfur wollastonite, tricalcium aluminate, calcium hydroxide, calcium sulfate and calcium carbonate are detected in the sample, the situation that diseases possibly occur in the future (the quantity of related products in the present stage is insufficient to generate obvious diseases) is indicated, the prevention effect is poor, and the measures of the application need to be continuously developed for prevention; (4) if ettringite and carbon sulfur wollastonite are detected in the sample, but the sample does not contain tricalcium aluminate and calcium hydroxide, the risk of generating ettringite by continuous reaction is not shown, but the existing ettringite needs to be continuously remedied and eliminated.
10. The method according to claim 1, characterized in that: the weather conditions applicable to the method are as follows: the ambient temperature is not lower than 5 ℃ and not higher than 40 ℃, and the relative humidity is not lower than 30%.
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| CN107165003A (en) * | 2017-05-18 | 2017-09-15 | 浙江大学 | It is a kind of to be used to administer the regulation method that plate-type ballastless track railway bed is risen soil |
| CN108609934A (en) * | 2018-07-03 | 2018-10-02 | 济南大学 | A kind of high compact Sulfate corrosion-resistant concrete and preparation method thereof |
| CN109440542A (en) * | 2018-10-19 | 2019-03-08 | 浙江大学 | A method of for administering high-speed railway plate type ballastless track Mud pumping |
| CN109736141A (en) * | 2019-01-29 | 2019-05-10 | 中建新疆建工土木工程有限公司 | The anti-freeze expansion structural body and paving method of Railway Roadbed in Permafrost Regions |
| CN111875276A (en) * | 2020-06-30 | 2020-11-03 | 华北理工大学 | Synergistic inhibition method for sulfate erosion and alkali aggregate reaction and application thereof |
| CN115073076A (en) * | 2022-05-31 | 2022-09-20 | 四川能达工程检测有限公司 | Sulfate erosion resistant mortar and preparation method thereof |
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