EP1027478A1 - Method for improving corrosion resistance of reinforced concrete - Google Patents

Method for improving corrosion resistance of reinforced concrete

Info

Publication number
EP1027478A1
EP1027478A1 EP98951521A EP98951521A EP1027478A1 EP 1027478 A1 EP1027478 A1 EP 1027478A1 EP 98951521 A EP98951521 A EP 98951521A EP 98951521 A EP98951521 A EP 98951521A EP 1027478 A1 EP1027478 A1 EP 1027478A1
Authority
EP
European Patent Office
Prior art keywords
layer
zinc
spray
polyurethane resin
reinforced concrete
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP98951521A
Other languages
German (de)
French (fr)
Other versions
EP1027478B1 (en
Inventor
Michael Knepper
Jochen Spriestersbach
Jürgen Wisniewski
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Grillo Werke AG
Original Assignee
Grillo Werke AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Grillo Werke AG filed Critical Grillo Werke AG
Publication of EP1027478A1 publication Critical patent/EP1027478A1/en
Application granted granted Critical
Publication of EP1027478B1 publication Critical patent/EP1027478B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
    • C23C4/18—After-treatment
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
    • C23F13/00—Inhibiting corrosion of metals by anodic or cathodic protection
    • C23F13/02—Inhibiting corrosion of metals by anodic or cathodic protection cathodic; Selection of conditions, parameters or procedures for cathodic protection, e.g. of electrical conditions
    • C23F13/06—Constructional parts, or assemblies of cathodic-protection apparatus
    • C23F13/08—Electrodes specially adapted for inhibiting corrosion by cathodic protection; Manufacture thereof; Conducting electric current thereto
    • C23F13/10—Electrodes characterised by the structure
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
    • C23F2201/00—Type of materials to be protected by cathodic protection
    • C23F2201/02—Concrete, e.g. reinforced

Definitions

  • the present invention relates to a method for improving the corrosion resistance of reinforced concrete coated with a thermal spray coating of metals, in particular of zinc or zinc alloys.
  • Thermal spray coatings made of zinc or zinc aluminum alloys are used for the surface finishing of metals, plastics, concrete, cardboard etc. Among other things, they improve the temperature resistance, the wear behavior and the electrical conductivity of the substrate materials.
  • EP-A-0 677 592 discloses a method for improving the adhesive strength of thermal spray coatings made of metals, metal oxides or hard materials, in particular zinc, aluminum and their alloys, the spray coatings after spraying with a one-component, moisture-curing polyurethane resin be coated. This process has become particularly important for steel workpieces. It is mentioned that customary coating systems which are compatible with polyurethane resins can be applied to the polyurethane resin layer applied in this way. No examples of this are mentioned. However, it had already been observed that materials such as alkyd resins, epoxy resins or PVC resins would not adhere sufficiently to the metal spray layers without the polyurethane resin layer.
  • the present invention has for its object to improve the corrosion resistance of with a thermal spray layer made of metals, in particular zinc or To provide zinc alloys, coated reinforced concrete, where possible the adhesive strength of the sprayed layer on the concrete should also be improved.
  • the spray layer is electrically connected to the reinforcement of the reinforced concrete and is additionally coated with a polyurethane resin, which is applied as a low-viscosity solution in organic solvents.
  • the polyurethane resin layer is preferably applied so thinly that no closed film forms, but only the pores of the spray layer are closed.
  • an epoxy resin layer is additionally applied after the polyurethane resin has cured.
  • This epoxy resin layer is applied so that it preferably has a thickness of 200 to 400 microns after curing.
  • Polyurethane layers and layers of mixtures of epoxy resins and polyurethanes are also well suited.
  • the spray layer made of zinc or zinc alloys on the concrete is generally 100 to 400 ⁇ m, preferably 150 to 300 ⁇ m. Spray layers of this type have values between 1.0 and 2.0 MPa in the case of adhesive strength measurements by means of forehead deduction. After the application of the polyurethane resin layer, the adhesion of the zinc layer to the concrete surprisingly increases to 2.5 to 3.0 MPa. If an epoxy resin layer is applied after the polyurethane layer has hardened, adhesive strengths between 2.5 and 3.5 MPa are measured after it has hardened.
  • the layer applied according to the invention is electrically connected to the reinforcement of the reinforced concrete. For this it is necessary to establish an electrically conductive connection between the metal reinforcement of the reinforced concrete and the surface of the concrete. This is a measure that has so far only been carried out hesitantly, since parts of the reinforcement that are not covered by the cement are covered with the. Come into contact with the outside world and are actually regarded as defects where corrosion of the reinforced concrete occurs particularly quickly. According to the invention, it is also possible to use the layers as anodes for active cathodic corrosion protection with the aid of external current.
  • Another unforeseeable advantage of the method according to the invention is that the coating with polyurethane resin not only improves the adhesive strength of the spray layer on the concrete, but also the service life of the spray layer.
  • the self-corrosion of the zinc layer in damp weather conditions is greatly reduced and the service life of the spray layer is increased.
  • Corrosion tests in the salt spray test according to DIN 50121-SS have shown that a layer of 100 ⁇ m thickness is removed by 60% after 336 hours. After the application of the polyurethane resin layer, the removal of the zinc spray layer is only 13%. If an additional epoxy resin layer is applied, the intrinsic corrosion of the spray layer drops to practically 0.
  • the method according to the invention Before applying the spray layer made of metal, the method according to the invention must ensure that the reinforced concrete is cleaned beforehand, blasted, preheated to 70 ° to 90 ° C. and only then is the metal sprayed on.
  • the purity and roughness of the surface of the substrate are of particular importance. A certain sharpness of the profile is often even necessary to ensure the necessary adhesive strength. Preheating can only be dispensed with if it is ensured that the concrete surface is no longer damp. Otherwise the zinc spray coating will not have sufficient adhesive strength.
  • the metallic spraying materials for example wire flame spraying or wire arc spraying. This procedure differ primarily by different process temperatures and thus also by different application efficiencies.
  • the adhesive strength to the concrete depends not only on the surface preparation, but also on the type of concrete to be protected.
  • the spray layers are more or less dense depending on the thickness and type of spray. In order to ensure adequate protection against corrosion, the thicknesses should preferably be in the range between 150 and 300 ⁇ m.
  • a new structure made of reinforced concrete is prepared by means of compressed air jets up to the degree of cleaning Sa3 and an average roughness depth R z of 45 ⁇ m. Subsequently, the workpiece prepared in this way is cleaned of adhering contaminants as well as possible using compressed air, preheated to 70 to 90 ° C and provided with a 150 to 300 ⁇ m thick spray coating made of zinc.
  • the adhesive strength measurements carried out by pulling the forehead give values between 1.0 and 2.0 MPa.
  • the sprayed metal layer is then coated with a commercially available, low-viscosity 1-component PU coating solution using a brush so that no measurable layer build-up takes place.
  • part of the substrate was additionally coated with an epoxy resin layer.
  • the Amerlock 400 GFA material was used in layers between 200 and 400 ⁇ m thick. After this second layer had hardened, the adhesive strength was 2.5 to 3.5 MPa.
  • Example 2 The same zinc spray coating as in Example 1 was immediately coated with the epoxy resin.
  • the adhesive strength measurement by means of a forehead trigger remains at 1.0 to 2.0 MPa.
  • the adhesive strength of the epoxy layer on the zinc layer was not stable.
  • Anchor arches in need of renovation in a seaport are first externally freed of corroded concrete until the reinforcing bars are exposed. They are welded to one another in such a way that they are connected to one another in an electrically conductive manner. Electrical lines are also installed and insulated. Then repair mortar is applied in a thickness of up to 10 cm. After setting, a 300 ⁇ m thick spray layer made of zinc is applied to this, as in Example 1, and then coated with the low-viscosity PUR coating solution, care being taken, however, that no electrically conductive contact occurs between the reinforcing bars and the zinc layer. The zinc layer applied in this way acts as a sacrificial anode. The subsequent coating with the PUR solution increases the mechanical stability of the coating.
  • Example 1 The surface is then coated with an epoxy resin layer, as in Example 1, which has an average thickness of 400 ⁇ m. This creates a surface that is highly resistant to seawater and other corrosion, which ensures long-term protection of the concrete and the reinforcing bars embedded in it.

Abstract

The invention relates to a method for improving the corrosion resistance of reinforced concrete coated with a thermal spray coating made of metal, especially zinc or zinc alloys. The spray coating is electrically interconnected to the reinforcement and additionally coated with a polyurethane resin which is applied as a low viscosity solution in the organic solvents.

Description

Verfahren zur Verbesserung der Korrosionsbeständigkeit von Stahlbeton Process for improving the corrosion resistance of reinforced concrete
Gegenstand der vorliegenden Erfindung ist ein Verfahren zur Verbesserung der Korrosionsbeständigkeit von mit einer thermischen Spritzschicht aus Metallen, insbesondere aus Zink oder Zinklegierungen, beschichtetem Stahlbeton.The present invention relates to a method for improving the corrosion resistance of reinforced concrete coated with a thermal spray coating of metals, in particular of zinc or zinc alloys.
Thermische Spritzschichten aus Zink oder Zinkaluminiumlegierungen werden zur Oberflächenveredelung von Metallen, Kunststoffen, Beton, Pappe etc. eingesetzt. So verbessern sie unter anderem die Temperaturbeständigkeit, das Verschleißverhalten und die elektrische Leitf higkeit der Substratmaterialien.Thermal spray coatings made of zinc or zinc aluminum alloys are used for the surface finishing of metals, plastics, concrete, cardboard etc. Among other things, they improve the temperature resistance, the wear behavior and the electrical conductivity of the substrate materials.
Aus der EP-A-0 677 592 ist ein Verfahren bekannt zur Verbesserung der Haftfestigkeit von thermischen Spritzschichten aus Metallen, Metalloxiden oder Hartstoffen, insbesondere aus Zink, Aluminium und deren Legierungen, wobei die Spritzschichten nach dem Aufspritzen mit einem einkomponentigen, luftfeuchtigkeits- härtenden Polyurethanharz beschichtet werden. Besondere Bedeutung hat dieses Verfahren erlangt bei Werkstücken aus Stahl . Es wird erwähnt, daß auf die so aufgetragene Polyurethanharz- schicht übliche BeschichtungsSysteme aufgetragen werden können, die sich mit Polyurethanharzen vertragen. Beispiele hierfür sind nicht genannt. Es war aber bereits beobachtet worden, daß Materialien wie Alkydharze, Epoxyharze oder PVC-Harze ohne die Polyurethanharzschicht nicht auf den Spritzschichten aus Metall ausreichend haften.EP-A-0 677 592 discloses a method for improving the adhesive strength of thermal spray coatings made of metals, metal oxides or hard materials, in particular zinc, aluminum and their alloys, the spray coatings after spraying with a one-component, moisture-curing polyurethane resin be coated. This process has become particularly important for steel workpieces. It is mentioned that customary coating systems which are compatible with polyurethane resins can be applied to the polyurethane resin layer applied in this way. No examples of this are mentioned. However, it had already been observed that materials such as alkyd resins, epoxy resins or PVC resins would not adhere sufficiently to the metal spray layers without the polyurethane resin layer.
Die vorliegende Erfindung hat sich die Aufgabe gestellt, die Verbesserung der Korrosionsbeständigkeit von mit einer thermischen Spritzschicht aus Metallen, insbesondere aus Zink oder Zinklegierungen, beschichtetem Stahlbeton zur Verfügung zu stellen, wobei nach Möglichkeit auch die Haftfestigkeit der Spritzschicht auf dem Beton verbessert werden soll.The present invention has for its object to improve the corrosion resistance of with a thermal spray layer made of metals, in particular zinc or To provide zinc alloys, coated reinforced concrete, where possible the adhesive strength of the sprayed layer on the concrete should also be improved.
Diese Aufgabe wird erfindungsgemäß dadurch gelöst, daß die Spritzschicht mit der Bewehrung des Stahlbetons elektrisch verschaltet wird und zusätzlich mit einem Polyurethanharz beschichtet wird, welches als niedrigviskose Lösung in organischen Lösungsmitteln aufgetragen wird.This object is achieved in that the spray layer is electrically connected to the reinforcement of the reinforced concrete and is additionally coated with a polyurethane resin, which is applied as a low-viscosity solution in organic solvents.
Vorzugsweise wird die Polyurethanharzschicht so dünn aufgetragen, daß sich kein geschlossener Film bildet, sondern nur die Poren der Spritzschicht verschlossen werden.The polyurethane resin layer is preferably applied so thinly that no closed film forms, but only the pores of the spray layer are closed.
Besonders gute Ergebnisse werden erzielt, wenn nach dem Aushärten des Polyurethanharzes zusätzlich eine Epoxyharzschicht aufgebracht wird. Diese Epoxyharzschicht wird so aufgetragen, daß sie nach dem Aushärten vorzugsweise eine Dicke von 200 bis 400 μm aufweist. Weiterhin gut geeignet sind Polyurethanschichten sowie Schichten aus Gemischen von Epoxyharzen und Polyurethanen.Particularly good results are achieved if an epoxy resin layer is additionally applied after the polyurethane resin has cured. This epoxy resin layer is applied so that it preferably has a thickness of 200 to 400 microns after curing. Polyurethane layers and layers of mixtures of epoxy resins and polyurethanes are also well suited.
Die Spritzschicht aus Zink oder Zinklegierungen auf dem Beton beträgt im allgemeinen 100 bis 400 μm, vorzugsweise 150 bis 300 μm. Derartige Spritzschichten weisen bei Haftfestigkeitsmessungen mittels Stirnabzug Werte zwischen 1,0 und 2,0 MPa auf. Nach dem Auftrag der Polyurethanharzschicht steigt die Haftung der Zinkschicht auf dem Beton überraschenderweise auf 2,5 bis 3,0 MPa. Wird nach dem Aushärten der Polyurethanschicht eine Epoxyharzschicht aufgetragen, werden nach deren Aushärtung Haftfestigkeiten zwischen 2,5 und 3,5 MPa gemessen.The spray layer made of zinc or zinc alloys on the concrete is generally 100 to 400 μm, preferably 150 to 300 μm. Spray layers of this type have values between 1.0 and 2.0 MPa in the case of adhesive strength measurements by means of forehead deduction. After the application of the polyurethane resin layer, the adhesion of the zinc layer to the concrete surprisingly increases to 2.5 to 3.0 MPa. If an epoxy resin layer is applied after the polyurethane layer has hardened, adhesive strengths between 2.5 and 3.5 MPa are measured after it has hardened.
Wesentlich für den Erfolg des Verfahrens ist, daß die erfindungsgemäß aufgetragene Schicht mit der Bewehrung des Stahlbetons elektrisch verschaltet wird. Dazu ist es nötig, eine elektrisch leitende Verbindung zwischen der MetalIbewehrung des Stahlbetons und der Oberfläche des Betons herzustellen. Dies ist eine Maßnahme, die man bisher nur zögernd durchgeführt hat, da Teile der Bewehrung, die nicht vom Zement bedeckt sind mit der. Außenwelt in Berührung kommen und eigentlich als Fehlstellen angesehen werden, an denen es besonders rasch zu einer Korrosion des Stahlbetons kommt. Erfindungsgemäß ist es weiterhin möglich, die Schichten als Anoden zum aktiven kathodischen Korrosionsschutz zu verwenden unter Zuhilfenahme von Fremdstrom.It is essential for the success of the method that the layer applied according to the invention is electrically connected to the reinforcement of the reinforced concrete. For this it is necessary to establish an electrically conductive connection between the metal reinforcement of the reinforced concrete and the surface of the concrete. This is a measure that has so far only been carried out hesitantly, since parts of the reinforcement that are not covered by the cement are covered with the. Come into contact with the outside world and are actually regarded as defects where corrosion of the reinforced concrete occurs particularly quickly. According to the invention, it is also possible to use the layers as anodes for active cathodic corrosion protection with the aid of external current.
Ein weiterer nicht vorhersehbarer Vorteil des erfindungsgemäßen Verfahrens besteht darin, daß durch die Beschichtung mit Polyurethanharz nicht nur die Haftfestigkeit der Spritzschicht auf dem Beton verbessert wird, sondern auch die Lebensdauer der Spritzschicht. Die Eigenkorrosion der Zinkschicht bei feuchten Witterungsbedingungen wird stark herabgesetzt und somit die Lebensdauer der Spritzschicht erhöht. Korrosionsversuche im Salzsprühtest nach DIN 50121-SS haben gezeigt, daß eine 100 μm dicke Schicht nach 336 Stunden bereits zu 60% abgetragen wird. Nach dem Auftrag der Polyurethanharzschicht beträgt der Abtrag der Zinkspritzschicht nur noch 13%. Sofern zusätzlich eine Epoxidharzschicht aufgetragen wird, sinkt die Eigenkorrosion der Spritzschicht auf praktisch 0.Another unforeseeable advantage of the method according to the invention is that the coating with polyurethane resin not only improves the adhesive strength of the spray layer on the concrete, but also the service life of the spray layer. The self-corrosion of the zinc layer in damp weather conditions is greatly reduced and the service life of the spray layer is increased. Corrosion tests in the salt spray test according to DIN 50121-SS have shown that a layer of 100 μm thickness is removed by 60% after 336 hours. After the application of the polyurethane resin layer, the removal of the zinc spray layer is only 13%. If an additional epoxy resin layer is applied, the intrinsic corrosion of the spray layer drops to practically 0.
Vor dem Auftrag der Spritzschicht aus Metall muß beim erfindungsgemäßen Verfahren dafür gesorgt werden, daß der Stahlbeton zuvor gereinigt wird, gestrahlt wird, vorgewärmt wird auf 70° bis 90 °C und erst dann das Metall aufgespritzt wird. Dabei sind die Reinheit und die Rauheit der Oberfläche des Substrates von besonderer Bedeutung. Eine gewisse Scharfkantigkeit des Profils ist oftmals sogar notwendig, um die notwendige Haftfestigkeit zu gewährleisten. Auf die Vorwärmung kann nur dann verzichtet werden, wenn sichergestellt ist, daß die Betonoberfläche nicht mehr feucht ist. Andernfalls besitzt die Spritzschicht aus Zink nicht die ausreichende Haftfestigkeit.Before applying the spray layer made of metal, the method according to the invention must ensure that the reinforced concrete is cleaned beforehand, blasted, preheated to 70 ° to 90 ° C. and only then is the metal sprayed on. The purity and roughness of the surface of the substrate are of particular importance. A certain sharpness of the profile is often even necessary to ensure the necessary adhesive strength. Preheating can only be dispensed with if it is ensured that the concrete surface is no longer damp. Otherwise the zinc spray coating will not have sufficient adhesive strength.
Für die metallischen Spritzwerkstoffe können verschiedene Spritzverfahren angewendet werden, beispielsweise das Drahtflammspritzen oder das Drahtlichtbogenspritzen. Diese Verfahren unterscheiden sich vor allem durch verschiedene Prozeßtemperaturen und damit auch durch unterschiedliche Auftragswirkungsgrade. Die Haftfestigkeiten auf den Beton hängen nicht nur von der Oberflächenvorbehandlung ab, sondern auch von der Art des zu schützenden Betons. Die Spritzschichten sind je nach Dicke und Spritzart mehr oder weniger dicht. Um einen ausreichenden Korrosionsschutz zu gewährleisten, sollten die Dicken vorzugsweise im Bereich zwischen 150 und 300 μm liegen.Various spraying methods can be used for the metallic spraying materials, for example wire flame spraying or wire arc spraying. This procedure differ primarily by different process temperatures and thus also by different application efficiencies. The adhesive strength to the concrete depends not only on the surface preparation, but also on the type of concrete to be protected. The spray layers are more or less dense depending on the thickness and type of spray. In order to ensure adequate protection against corrosion, the thicknesses should preferably be in the range between 150 and 300 μm.
Versuche eine Epoxyschicht unmittelbar auf die Spritzschicht aufzubringen, haben zu völlig unbefriedigende Ergebnissen geführt, während bei zuvor vorgenommenem erfindungsgemäßen Auftrag einer Polyurethanschicht überraschend gute Ergebnisse beobachtet werden.Attempts to apply an epoxy layer directly to the sprayed layer have led to completely unsatisfactory results, while surprisingly good results are observed when a polyurethane layer has been applied according to the invention previously.
Eine eindeutige Erklärung dieser Ergebnisse gibt es bisher nicht, jedoch spricht einiges dafür, daß die Urethan-Gruppen in der Lage sind, beim Abbinden mit Hydroxyl -Gruppen zu reagieren, wobei nicht nur Reste von Feuchtigkeit gebunden werden, sondern auch feste Bindungen zwischen dem aufgespritzten Metall und dem Polyurethanharz entstehen. Erstaunlich ist auch, daß besonders gute Ergebnisse erzielt werden, wenn nur so dünne Schichten aufgetragen werden, daß gerade die Poren des Spritzmetalls gefüllt sind, jedoch noch kein geschlossener Film gebildet wird. Die dünnen Schichten können beispielsweise aufgetragen werden durch Streichen, Rollen oder Sprühen, jedoch sollte ein meßbarer Schichtaufbau nicht stattfinden. Dennoch bewirkt bereits diese dünne Schicht eine starke Verminderung der Eigenkorrosion durch feuchte Witterungsbedingungen bei gleichzeitiger Erhöhung der Haftfestigkeit der Metallschicht auf dem Beton.There is no clear explanation of these results so far, but there are some indications that the urethane groups are able to react with hydroxyl groups when setting, whereby not only residues of moisture are bound, but also firm bonds between the sprayed on Metal and the polyurethane resin arise. It is also astonishing that particularly good results are achieved if layers are applied which are so thin that the pores of the spray metal are just filled, but no closed film has yet been formed. The thin layers can be applied, for example, by brushing, rolling or spraying, but a measurable layer structure should not take place. Nevertheless, even this thin layer causes a strong reduction in self-corrosion due to damp weather conditions while increasing the adhesive strength of the metal layer on the concrete.
Nach dem Aushärten dieses Urethanlacks kann eine weitere Verbesserung insbesondere durch Aufbringen einer Deckschicht aus Epoxydharz erzielt werden, wobei beispielsweise der Lack Amer- lock 400 GFR von der Firma Ameron, USA zu hervorragenden Ergebnissen geführt hat. Diese zusätzliche Epoxydharzschicht wird vor allem verwendet, wenn es sich um mechanisch stark belastete Flächen handelt. Gut geeignet sind aber auch Schichten aus Polyurethan oder Gemischen von Epoxyharzen und Polyurethanen.After this urethane lacquer has hardened, a further improvement can be achieved in particular by applying a top layer of epoxy resin, the Amerlock 400 GFR lacquer from Ameron, USA, for example, leading to excellent results. This additional epoxy resin layer will especially used when the surfaces are subject to high mechanical loads. Layers of polyurethane or mixtures of epoxy resins and polyurethanes are also very suitable.
Das erfindungsgemäße Verfahren wird durch die nachfolgenden Beispiele näher erläutert:The process according to the invention is explained in more detail by the following examples:
Beispiel 1example 1
Ein neues Bauwerk aus Stahlbeton wird mittels Druckluftstrahlen bis zum Säuberungsgrad Sa3 und einer mittleren Rauhtiefe Rz von 45 μm vorbereitet. Anschließend wird das so vorbereitete Werkstück von anhaftenden Verunreinigungen so gut wie möglich mittels Druckluft gesäubert, auf 70 bis 90 °C vorgewärmt und mit einer 150 bis 300 μm dicken Spritzschicht aus Zink versehen. Die vorgenommenen Haftfestigkeitsmessungen mittels Stirnabzug ergeben Werte zwischen 1,0 und 2,0 MPa. Anschließend wird die Spritzmetallschicht mit einer handelsüblichen, niedrigviskosen 1 K-PUR-Beschichtungslösung mittels Pinselauftrag so beschichtet, daß kein meßbarer Schichtaufbau stattfindet. Verwendet wurde der Polyurethanlack der Firma Steelpaint GmbH, Kitzingen.A new structure made of reinforced concrete is prepared by means of compressed air jets up to the degree of cleaning Sa3 and an average roughness depth R z of 45 μm. Subsequently, the workpiece prepared in this way is cleaned of adhering contaminants as well as possible using compressed air, preheated to 70 to 90 ° C and provided with a 150 to 300 μm thick spray coating made of zinc. The adhesive strength measurements carried out by pulling the forehead give values between 1.0 and 2.0 MPa. The sprayed metal layer is then coated with a commercially available, low-viscosity 1-component PU coating solution using a brush so that no measurable layer build-up takes place. The polyurethane varnish from Steelpaint GmbH, Kitzingen, was used.
Nach dem Trocknen- des Anstriches läßt sich feststellen, daß die Haftfestigkeit der Zinkschicht auf 2,5 bis 3,0 MPa angestiegen ist .After the paint has dried, it can be seen that the adhesive strength of the zinc layer has risen to 2.5 to 3.0 MPa.
Nach der Aushärtung der Polyurethanschicht wurde ein Teil des Substrats zusätzlich mit einer Epoxydharzschicht überzogen. Verwendet wurde das Material Amerlock 400 GFA in Schichtstärken zwischen 200 und 400 μm. Nach dem Aushärten dieser zweiten Schicht betrug die Haftfestigkeit 2,5 bis 3,5 MPa.After the polyurethane layer had hardened, part of the substrate was additionally coated with an epoxy resin layer. The Amerlock 400 GFA material was used in layers between 200 and 400 μm thick. After this second layer had hardened, the adhesive strength was 2.5 to 3.5 MPa.
Korrosionsversuche im Salzsprühtest nach DIN 50121-SS ergab, daß praktisch kein meßbarer Abtrag der Zinkschicht festzustellen war. VergleichsversucheCorrosion tests in the salt spray test according to DIN 50121-SS showed that there was practically no measurable removal of the zinc layer. Comparative tests
Die gleiche Spritzschicht aus Zink wie im Beispiel 1 wurde unmittelbar mit dem Epoxydharz beschichtet. Die Haftfestigkeitsmessung mittels Stirnabzug bleibt bei 1,0 bis 2,0 MPa. Die Haftfestigkeit der Epoxydschicht auf der Zinkschicht war nicht beständig .The same zinc spray coating as in Example 1 was immediately coated with the epoxy resin. The adhesive strength measurement by means of a forehead trigger remains at 1.0 to 2.0 MPa. The adhesive strength of the epoxy layer on the zinc layer was not stable.
Beispiel 2Example 2
Renovierungsbedürftige Ankerbögen in einem Seehafen werden zunächst äußerlich vom korrodierten Beton befreit bis die Bewehrungseisen frei liegen. Sie werden so miteinander verschweißt, daß sie insgesamt elektrisch leitend miteinander verbunden sind. Weiterhin werden elektrische Leitungen installiert und isoliert. Anschließend wird Reparaturmörtel in einer Stärke von bis zu 10 cm aufgetragen. Nach dem Abbinden wird auf diesen wie im Beispiel 1 eine 300 μm dicke Spritzschicht aus Zink aufgetragen und anschließend mit der niedrigviskosen PUR-Beschichtungslosung beschichtet, wobei jedoch dafür Sorge getragen wird, daß kein elektrisch leitender Kontakt zwischen den Bewehrungseisen und der Zinkschicht entsteht. Die so aufgetragene Zinkschicht wirkt als Opferanode. Durch die anschließende Beschichtung mit der PUR-Lösung erhöht sich die mechanische Stabilität der Beschichtung. Anschließend wird die Fläche wie im Beispiel 1 mit einer Epoxydharzschicht überzogen, die eine durchschnittliche Dicke von 400 μm aufweist. Es entsteht so eine gegen Seewasser und sonstige Korrosion hochbeständige Oberfläche, die einen langfristigen Schutz des Betons und der darin eingelagerten Bewehrungseisen gewährleistet. Anchor arches in need of renovation in a seaport are first externally freed of corroded concrete until the reinforcing bars are exposed. They are welded to one another in such a way that they are connected to one another in an electrically conductive manner. Electrical lines are also installed and insulated. Then repair mortar is applied in a thickness of up to 10 cm. After setting, a 300 μm thick spray layer made of zinc is applied to this, as in Example 1, and then coated with the low-viscosity PUR coating solution, care being taken, however, that no electrically conductive contact occurs between the reinforcing bars and the zinc layer. The zinc layer applied in this way acts as a sacrificial anode. The subsequent coating with the PUR solution increases the mechanical stability of the coating. The surface is then coated with an epoxy resin layer, as in Example 1, which has an average thickness of 400 μm. This creates a surface that is highly resistant to seawater and other corrosion, which ensures long-term protection of the concrete and the reinforcing bars embedded in it.

Claims

Patentansprüche claims
1. Verfahren zur Verbesserung der Korrosionsbeständigkeit von mit einer thermischen Spritzschicht aus Metallen, insbesondere aus Zink oder Zinklegierungen, beschichtetem Stahlbeton, dadurch gekennzeichnet, daß die Spritzschicht mit der Bewehrung elektrisch verschaltet wird und zusätzlich mit einem Polyurethanharz beschichtet wird, welches als niedrigviskose Lösung in organischen Lösungsmitteln aufgetragen wird.1. Process for improving the corrosion resistance of reinforced concrete coated with a thermal spray layer made of metals, in particular zinc or zinc alloys, characterized in that the spray layer is electrically connected to the reinforcement and is additionally coated with a polyurethane resin, which as a low-viscosity solution in organic Solvents is applied.
2. Verfahren gemäß Anspruch, dadurch gekennzeichnet, daß die Polyurethanharzschicht so dünn aufgetragen wird, daß sich kein geschlossener Film bildet, sondern nur die Poren der Spritzschicht verschlossen werden.2. The method according to claim, characterized in that the polyurethane resin layer is applied so thin that no closed film forms, but only the pores of the spray layer are closed.
3. Verfahren gemäß Anspruch 1 oder 2, dadurch gekennzeichnet, daß nach dem Aushärten des Polyurethanharzes zusätzlich eine Epoxyharzschicht, eine Polyurethanharzschicht oder eine Schicht aus einem Gemisch von Epoxyden und Polyurethanen aufgebracht wird.3. The method according to claim 1 or 2, characterized in that after the curing of the polyurethane resin, an epoxy resin layer, a polyurethane resin layer or a layer of a mixture of epoxies and polyurethanes is additionally applied.
4. Verfahren gemäß einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß die zusätzliche Harzschicht so aufgetragen wird, daß sie nach dem Aushärten eine Dicke von 200 bis 400 μm aufweist. 4. The method according to any one of claims 1 to 3, characterized in that the additional resin layer is applied so that it has a thickness of 200 to 400 microns after curing.
EP98951521A 1997-10-31 1998-10-14 Method for improving corrosion resistance of reinforced concrete Expired - Lifetime EP1027478B1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE19748105 1997-10-31
DE19748105A DE19748105C1 (en) 1997-10-31 1997-10-31 Increasing corrosion-resistance of thermally sprayed metal coating on steel-reinforced cement concrete
PCT/EP1998/006512 WO1999023282A1 (en) 1997-10-31 1998-10-14 Method for improving corrosion resistance of reinforced concrete

Publications (2)

Publication Number Publication Date
EP1027478A1 true EP1027478A1 (en) 2000-08-16
EP1027478B1 EP1027478B1 (en) 2002-01-30

Family

ID=7847187

Family Applications (1)

Application Number Title Priority Date Filing Date
EP98951521A Expired - Lifetime EP1027478B1 (en) 1997-10-31 1998-10-14 Method for improving corrosion resistance of reinforced concrete

Country Status (15)

Country Link
US (1) US6224943B1 (en)
EP (1) EP1027478B1 (en)
CN (1) CN1207444C (en)
AU (1) AU745500B2 (en)
BR (1) BR9813171A (en)
CA (1) CA2307831C (en)
DE (2) DE19748105C1 (en)
DK (1) DK1027478T3 (en)
ES (1) ES2172223T3 (en)
HK (1) HK1028795A1 (en)
IL (1) IL135739A (en)
NO (1) NO319769B1 (en)
PT (1) PT1027478E (en)
TR (1) TR200001150T2 (en)
WO (1) WO1999023282A1 (en)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2818274B1 (en) 2000-12-18 2003-02-14 Alto Btp PROCESS FOR THE PROTECTION, REPAIR AND CONSOLIDATION OF WORKS OF ARTS COMPRISING METAL ELEMENTS INCLUDED IN A CONCRETE, PLASTER, CEMENT OR MORTAR MATRIX
US6592947B1 (en) 2002-04-12 2003-07-15 Ford Global Technologies, Llc Method for selective control of corrosion using kinetic spraying
WO2005003061A1 (en) * 2003-07-03 2005-01-13 Grillo-Werke Ag Multi-layered surface protection for reinforced concrete in order to improve protection against corrosion for reinforced concrete constructions or reinforced concrete building components and method for the production thereof
US7422789B2 (en) * 2003-10-27 2008-09-09 Polyone Corporation Cathodic protection coatings containing carbonaceous conductive media
US7838079B2 (en) * 2004-11-17 2010-11-23 Battelle Energy Alliance, Llc Coated armor system and process for making the same
DE102007033423B4 (en) * 2007-07-18 2015-10-08 Torkret Gmbh Protective device for corrosion-prone, driveable parking garage floor surfaces made of reinforced concrete
EP2072205A1 (en) * 2007-12-17 2009-06-24 Rovalma SA Method for producing highly mechanically demanded pieces and specially tools from low cost ceramics or polymers
CN103088282A (en) * 2013-02-05 2013-05-08 华北水利水电学院 Method for thermal spraying of nanometer cemented carbide-polyurethane composite coat on surface of stainless steel
CA2981895A1 (en) * 2015-05-01 2016-11-10 Valspar Sourcing, Inc. High-performance textured coating
CN106738234A (en) * 2016-11-15 2017-05-31 黄河科技学院 A kind of production technology of corrosion-resistant prefabricated assembling type reinforced concrete inspection shaft

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2140456A (en) 1982-12-02 1984-11-28 Taywood Engineering Limited Cathodic protection
US4506485A (en) * 1983-04-12 1985-03-26 State Of California, Department Of Transportation Process for inhibiting corrosion of metal embedded in concrete and a reinforced concrete construction
US4619557A (en) * 1984-05-02 1986-10-28 Conoco Inc. Corrosion protection for mooring and riser elements of a tension leg platform
US5069822A (en) * 1987-06-15 1991-12-03 Callaghan Thomas M Protective coating for reinforced concrete
GB2216140A (en) * 1988-01-13 1989-10-04 John Avery Edwards A method and design for corrosion protection coating system for application to ferrous and non-ferrous metals and concrete/cementitious surfaces
JPH01224285A (en) * 1988-03-02 1989-09-07 Hokushin Doken Kk Production of highly durable film on concrete surface
DD275487A1 (en) * 1988-09-12 1990-01-24 Freiberg Brennstoffinst ANODE FOR THE KATODIC CORROSION PROTECTION OF STEEL OR TENDER CONCRETE
CA2040610A1 (en) * 1990-05-21 1991-11-22 John E. Bennett Apparatus for the removal of chloride from reinforced concrete structures
GB9215502D0 (en) * 1992-07-21 1992-09-02 Ici Plc Cathodic protection system and a coating and coating composition therefor
JP3040613B2 (en) * 1992-10-07 2000-05-15 大日本塗料株式会社 Corrosion protection method for reinforced concrete structures
US5879817A (en) * 1994-02-15 1999-03-09 Eltech Systems Corporation Reinforced concrete structure
EP0677592B1 (en) * 1994-04-14 1998-12-30 Grillo-Werke AG Method for enhancing the band strength of thermally sprayed layers of metals, metal oxides and hard materials

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9923282A1 *

Also Published As

Publication number Publication date
NO20002130L (en) 2000-04-26
US6224943B1 (en) 2001-05-01
IL135739A0 (en) 2001-05-20
IL135739A (en) 2004-09-27
DK1027478T3 (en) 2002-05-21
CA2307831A1 (en) 1999-05-14
NO319769B1 (en) 2005-09-12
AU745500B2 (en) 2002-03-21
PT1027478E (en) 2002-06-28
NO20002130D0 (en) 2000-04-26
CA2307831C (en) 2006-12-12
HK1028795A1 (en) 2001-03-02
CN1276839A (en) 2000-12-13
AU9750198A (en) 1999-05-24
ES2172223T3 (en) 2002-09-16
CN1207444C (en) 2005-06-22
DE19748105C1 (en) 1998-10-29
TR200001150T2 (en) 2000-08-21
EP1027478B1 (en) 2002-01-30
WO1999023282A1 (en) 1999-05-14
DE59802985D1 (en) 2002-03-14
BR9813171A (en) 2000-08-22

Similar Documents

Publication Publication Date Title
EP1802788B1 (en) Galvanic anode system for corrosion protection of steel and method for production thereof
EP1027478B1 (en) Method for improving corrosion resistance of reinforced concrete
US5431795A (en) Cathodic protection system and a coating and coating composition therefor
CH641199A5 (en) PAINT SYSTEM.
EP0638368A1 (en) Process for coating composite profiles with powder lacquers
DE10127770A1 (en) Production of anticorrosion coating on magnesium or alloy part, used in vehicle or aircraft construction, involves oxidation in aluminum phosphate electrolyte containing vanadium, molybdenum and/or manganese compound
EP0679853B1 (en) Coating for end plates and heat exchanger tubes for cooling medium
KR100721215B1 (en) Method for repairing and reinforcing damage of reinforced concrete using gel-type sacrificial anode and waterproof material having exellent insulating properties
EP1852479A1 (en) Method for protecting dynamically loaded surfaces and coating therefor
DE2263013A1 (en) METHOD OF JOINING TITANIUM OR TANTALUM WITH COPPER OR IRON
KR100245851B1 (en) Gluing method of gluing, anti-rust paints for steel pipe and steel bar
DE3232755C2 (en) Zinc dust primer system for deformable phosphated or chromated sheet steel
DE102012109220B4 (en) Uses of a composition and method for the formation of calcium hydroxide layers on surfaces
EP0096736A2 (en) Process for obtaining a frictional connection between concrete and duroplast-laminated and lacquered objects
EP1318247A1 (en) Concrete structure
DE19828827C1 (en) Thermal sprayed corrosion layer for reinforced concrete and method of manufacturing the same
EP0677592B1 (en) Method for enhancing the band strength of thermally sprayed layers of metals, metal oxides and hard materials
EP3202810B1 (en) Running surface coating for metal floors
JPH04297643A (en) Reinforced concrete structure and structural member, and electric protection method for reinforced concrete
KR20010054409A (en) Coating method of superior anti-corrosion layer on the surface of galvanized steel wire and strand
DE3706995A1 (en) Process for refurbishing steel-reinforced concrete
DE102004059008A1 (en) Coating metal components comprises selectively applying a less noble metal than that of the component
EP0108828B1 (en) Method for restoration of steel reinforced concrete
DE4333894C1 (en) Process for resin coating a metal surface
DD209661A1 (en) LONG-TERM STORAGE ON ALUMINUM FACADE ELEMENTS

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20000420

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): BE DE DK ES FI FR GB GR IT LU NL PT SE

17Q First examination report despatched

Effective date: 20001121

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): BE DE DK ES FI FR GB GR IT LU NL PT SE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20020130

REF Corresponds to:

Ref document number: 59802985

Country of ref document: DE

Date of ref document: 20020314

REG Reference to a national code

Ref country code: DK

Ref legal event code: T3

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 20020501

REG Reference to a national code

Ref country code: GR

Ref legal event code: EP

Ref document number: 20020400540

Country of ref document: GR

REG Reference to a national code

Ref country code: PT

Ref legal event code: SC4A

Free format text: AVAILABILITY OF NATIONAL TRANSLATION

Effective date: 20020308

ET Fr: translation filed
REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2172223

Country of ref document: ES

Kind code of ref document: T3

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LU

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20021014

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 18

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DK

Payment date: 20151026

Year of fee payment: 18

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20151026

Year of fee payment: 18

Ref country code: GR

Payment date: 20151021

Year of fee payment: 18

Ref country code: GB

Payment date: 20151026

Year of fee payment: 18

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 20151026

Year of fee payment: 18

Ref country code: NL

Payment date: 20151026

Year of fee payment: 18

Ref country code: PT

Payment date: 20151005

Year of fee payment: 18

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 19

REG Reference to a national code

Ref country code: DK

Ref legal event code: EBP

Effective date: 20161031

REG Reference to a national code

Ref country code: NL

Ref legal event code: MM

Effective date: 20161101

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20161014

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20161014

Ref country code: GR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20170504

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20161015

Ref country code: PT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20170417

Ref country code: NL

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20161101

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 20

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20161014

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DK

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20161031

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20171023

Year of fee payment: 20

Ref country code: DE

Payment date: 20171030

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: ES

Payment date: 20171103

Year of fee payment: 20

Ref country code: BE

Payment date: 20171023

Year of fee payment: 20

REG Reference to a national code

Ref country code: DE

Ref legal event code: R071

Ref document number: 59802985

Country of ref document: DE

REG Reference to a national code

Ref country code: BE

Ref legal event code: MK

Effective date: 20181014

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20220127

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20181015