KR101071353B1 - Method for constructuring assembling-type steel pier having exellent corrosion resistant - Google Patents

Abstract

The present invention relates to a method for installing a prefabricated steel structure piers for constructing a pier to be built in the sea or riverbed as a prefabricated steel structure and to prevent the corrosion of the inside and outside of the bridge economically to improve the safety life of the pier,

Installing a steel pipe foundation pile by a drilling method so as to be fixed to a rock and filling sand inside the steel pipe with impregnating corrosion inhibitor;

Fabricating a pier pedestal and assembling the steel pipe foundation pile and the underwater welding method;

Filling a concrete mixture impregnated with a corrosion inhibitor into the bridge pedestal;

Assembling a steel pier to the upper surface of the pier pedestal by an underwater welding method, and filling a concrete mixture impregnated with a corrosion inhibitor into the pier; And

Negatively polarizing the pier outer surface by an electrical method to prevent corrosion of the outer surface of the pier so as not to contact the pier;

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Prefabricated bridge piers, steel structure, cathode method, corrosion inhibitor, external power method, sacrificial anode method

Description

METHOOD FOR CONSTRUCTURING ASSEMBLING-TYPE STEEL PIER HAVING EXELLENT CORROSION RESISTANT}

The present invention relates to a method for installing a prefabricated steel structure piers having excellent corrosion resistance that can prevent corrosion of the inner and outer surfaces of the piers using the prefabricated steel structure in the bridge construction of the bridge.

Existing reinforced concrete bridge piers have about 60% corrosion protection technology of internal reinforcing bars, which requires enormous cost of corrosion due to the corrosion of reinforcing bridges, and safety life is designed for 60 ~ 100 years even if maintenance costs are expensive. Have no choice but to.

1 shows an installation example of a conventional non-assembled reinforced concrete bridge piers.

As shown in FIG. 1, when installing reinforced concrete bridge piers by non-assembly method, it is necessary to reinforce reinforcing bars and cast concrete, so construction of piers, formwork, concrete placing, formwork removal, impact prevention facilities Installation and demolition work has had a problem that requires a lot of time and construction costs.

In addition, in maintenance, concrete breaks down due to frequent waves and impacts of suspended solids and neutralizes concrete due to seawater, and concrete falls off. Corrosion occurs due to exposure of internal reinforcing bars. There was a problem that high cost is required.

The present invention is a prefabricated steel with excellent economic and corrosion resistance by using weather resistant and seawater resistant steel in the pier of the reinforced concrete structure, which has a conventional high cost, high corrosion resistance, high cost maintenance problems, and applying underwater welding technology and cathodic protection technology It is to provide a method for installing a structure piers.

The present invention provides a method for installing a steel structure piers excellent in corrosion resistance,

Installing a steel pipe foundation pile by a drilling method so as to be fixed to a rock and filling sand inside the steel pipe with impregnating corrosion inhibitor;

Fabricating a pier pedestal and assembling the steel pipe foundation pile and the underwater welding method;

Filling a concrete mixture impregnated with a corrosion inhibitor into the bridge pedestal;

Assembling a steel pier to the upper surface of the pier pedestal by an underwater welding method, and filling a concrete mixture impregnated with a corrosion inhibitor into the pier; And

Negatively polarizing the pier outer surface by an electrical method to prevent corrosion of the outer surface of the pier so as not to contact the pier;

It provides an installation method of prefabricated steel structure piers excellent corrosion resistance consisting of.

According to the pier installation method of the present invention, it is possible to reduce the cost by reducing the time required for the existing pier construction, and also to improve the strength, seismic characteristics, etc. by applying a high strength seawater resistance, weather resistance, and the like, By applying advanced anti-corrosion technology, it has the effect of prolonging the service life due to its excellent corrosion resistance.

In order to solve the above problems, the present inventors have studied in depth, and as a result of applying the pier, a high-corrosion-resistant steel (weather resistance and seawater high tensile strength steel) is applied, and the relative corrosion resistance is improved by using a method of improving the corrosion resistance by 95% or more. As a result, it has been found that high-strength piers with long safety life and low construction cost can be installed. Underwater welding technology has been developed as much as onshore, and the underwater assembly of steel structures can omit expensive water barrier construction, In addition, since the impact resistance of the steel also has the function of an anti-shock facility, it has been found that the construction cost of the bridge can be greatly reduced, thus completing the present invention.

Hereinafter, the method of installing the piers according to the present invention will be described in detail.

2 shows an example of a method for installing a piers in accordance with the present invention.

As shown in FIG. 2, in order to install a pier according to the present invention, first, the steel pipe foundation pile 11 is installed to reach a rock in the basement. At this time, the steel pipe foundation pile 11 is installed by applying a drilling method to drill the ground. The steel pipe foundation pile 11 is preferably made of steel excellent in high strength weather resistance and seawater resistance. The drilling method applied to the present invention is sufficient if the general method applied in water.

The inside of the steel pipe foundation pile 11 is filled with sand (21) impregnated with a corrosion inhibitor. The sand (21) impregnated with the corrosion inhibitor applied here is to prevent corrosion of the inner surface of the steel pipe foundation pile (11), which is made of a highly water-soluble silica compound as a liquid, and has a ratio of sand and weight ratio of 100: 3-5. It is preferable to mix and use. Examples include silica sol, potassium silicate, lithium silicate and the like.

After the steel pipe foundation pile 11 is installed, the piers pedestal 12 prepared in advance is assembled with the steel pipe foundation pile 11. At this time, the steel pipe foundation pile 11 and the pier pedestal 12 is connected using the underwater welding method. That is, the steel pipe foundation pile 11 and the support structure 14 of the piling base are connected using the underwater welding method. In general, the underwater welding method applied in the present invention is sufficient if the welding method applied in water.

The concrete mixture 22 in which the corrosion inhibitor is impregnated is filled in the pier pedestal 12. At this time, the concrete mixture 22 impregnated with the corrosion inhibitor is to prevent corrosion of the inner surface of the pier pedestal 12 and the support structure 14, so that the sodium silicate powder and the liquid silica sol (silicasol). It is preferable to mix and mix the mixture mixed with the weight ratio 10: 0.5-1 in the ratio of concrete and the weight ratio 100: 3-5.

After installing the piers pedestal 12 as described above, the steel piers structure 13 prepared in advance is assembled with the piers pedestal 12. Similarly, the support structure 14 of the pier pedestal 12 and the support structure 15 of the pier structure 13 are assembled by applying an underwater welding method or assembled using bolts.

In addition, the concrete mixture 23 impregnated with a corrosion inhibitor is filled to prevent corrosion of the inner surface of the bridge structure. At this time, the concrete mixture 23 impregnated with the corrosion inhibitor is to prevent corrosion of the inner surface of the bridge structure 13 and the support structure 15, and the sodium silicate powder and the liquid silica sol (silicasol). It is preferable to mix and mix the mixture mixed with the weight ratio 10: 0.5-1 in the ratio of concrete and the weight ratio 100: 3-5.

The pier pedestal 12 and the pier structure 13 is surrounded by a steel plate 16, the outside of which is excellent in high strength weather resistance and seawater resistance, the inside is provided with a support structure (14).

The material of the pier pedestal 12, the pier structure 13, the support structure 14 of the pier pedestal and the support structure 15 of the pier structure is preferably made of steel having excellent seawater resistance and weather resistance with improved corrosion resistance. . Such steel is a special steel obtained by alloying a small amount of copper (Cu), chromium (Cr), nickel (Ni), etc. with iron, and is used as a part of a ship's outer shell.

In order to prevent corrosion of the outer surface of the pier made of steel, a corrosion prevention anode is installed to negatively polarize the outer surface of the pier to cathodic method. Corrosion protection anodes shall not be in direct contact with the outer surface of the piers. This is because the outer surface of the steel piers is not polarized when the corrosion protection anode is in direct contact. In the cathode method, a method using an external power source (hereinafter referred to as an external power supply method) and a method using a sacrificial anode (hereinafter referred to as a sacrificial anode method) may be applied to each or together. Hereinafter, the sacrificial anode method and the external power method will be described in detail.

First, the sacrificial anode method will be described in detail.

In the sacrificial anode method of the present invention, as shown in FIG. 2, first, a sacrificial anode 31 is prepared, and both ends of the sacrificial anode 31 are electrically connected to an outer surface of the piers through an iron core 32. Install it. At this time, the sacrificial anode 31 is installed so as not to directly contact the outside of the steel piers. The iron core 32 is welded to the outer surface of the piers or installed using bolts.

The sacrificial anodes applicable to the sacrificial anode method are as follows.

High purity zinc anode (Zn: more than 99.99%, surface potential -1050mV), zinc alloy anode (Zn-Al-Si alloy, surface potential -1000 ~ 1050mV), aluminum alloy anode (Al-Zn-In alloy, Al-Zn-In-Si alloy, Al-Zn-In-Mg-Ca alloy, surface potential -1100 ~ 1200mV, magnesium alloy anode (Mg-Al-Zn-Mn alloy, surface potential -1400 ~ 1600mV) and the like can be used.

Since the sacrificial anode 31 has a lower surface potential than iron (natural surface potential -0.65V), the ionization tendency is strong, so electrons are emitted from the sacrificial anode having a high ionization tendency and transferred to the outer surface of the steel piers through the iron core. The cathode method is achieved through the process of polarization.

The sacrificial anode 31 utilizes the potential difference between the steel piers themselves, and when the circuit is formed by contacting water between the piers and the sacrificial anodes, the electrons generated when the sacrificial anodes with relatively high ionization tend to ionize first and melt into the water It is supplied to the steel pier outer surface to negatively polarize the potential of the steel pier to the anticorrosive potential to prevent ionization on the pier outer surface.

Hereinafter, the case of applying the external power method will be described in detail.

3 shows another example of a method for installing a piers according to the present invention, to which an external power supply method is applied.

In FIG. 3, the same parts as in FIG. 2 are denoted by the same reference numerals.

In order to apply the external power method as shown in FIG. 3, first, an insoluble anode 41 for an anticorrosive method is prepared, and one end of the insoluble anode 41 is connected to the positive power supply (+) of the external power source 43 through the lead wire 42. The insoluble anode 41 is connected to the lead wire 42, the external power source 43, and the other lead wire by connecting a negative pole of an external power source to the outer surface of the piers through another lead wire 44. It is installed so as to be electrically connected to the outer surface of the bridge through the (44), and then supply the electrons by supplying the anticorrosive current to the cathode method.

At this time, when the insoluble anode 41 is in contact with each other, since the anticorrosive circuit is not configured, the insoluble anode 41 does not come into contact with the piers 13. The lead wire 42 is preferably made of a lead wire coated with an insulating material.

According to the method, the insoluble anode 41 to which the positive electrode is connected is consumed by the supplied current, and electrons (negative electric) ride on the lead wire 42 through the negative pole to the steel material of the outer side of the pier, which is an anticorrosive object. Supplied to polarize the potential to the anticorrosive potential. Therefore, electrons are supplied to the outer surface of the steel pier to prevent corrosion.

The insoluble anode used herein is selected from among platinum anodes with low consumption rate, titanium anodes, and titanium-plated platinum anodes.

Figure 1 shows a cross section of a bridge made of conventional reinforced concrete.

Figure 2 shows a cross-section of the pier made by the pier installation method using the sacrificial anode method of the present invention.

Figure 3 shows a cross section of the pier made by the pier installation method using the external power supply method of the present invention.

4 is a cross-sectional view of the pier made by the pier installation method using the sacrificial anode method and the external power supply method of the present invention.

Description of the Drawings

11: steel foundation file

12: pier pedestal

13: steel piers

14, 15: internal support structure

16: welded connection of foundation pile and piers

17: Weld or bolted connection of piers and piers

21: Sand impregnated with corrosion inhibitor

22, 23: concrete mixture impregnated with corrosion inhibitor

31: Sacrifice Anode 32: Iron Core of Sacrifice Anode

41: insoluble anode 42: lead wire 43: external power source

Claims (10)

In the installation method of steel structure piers excellent in corrosion resistance, Installing a steel pipe foundation pile by a drilling method so as to be fixed to a rock and filling sand inside the steel pipe with impregnating corrosion inhibitor; Fabricating a pier pedestal and assembling the steel pipe foundation pile and the underwater welding method; Filling a concrete mixture impregnated with a corrosion inhibitor into the bridge pedestal; Assembling a steel pier to the upper surface of the pier pedestal by an underwater welding method, and filling a concrete mixture impregnated with a corrosion inhibitor into the pier; And Negatively polarizing the pier outer surface by an electrical method to prevent corrosion of the outer surface of the pier so as not to contact the pier; Method of installation of prefabricated steel structure piers excellent corrosion resistance characterized in that consisting of. The method of claim 1, wherein the sand impregnated with a corrosion inhibitor used in the steel pipe foundation pile is a high corrosion resistance prefabricated steel structure pier, characterized in that the sand is mixed with a ratio of 100: 3 to 5 by weight ratio. How to install. The method of claim 2, wherein the highly water-soluble silica compound is any one of silica sol, potassium silicate, and lithium silicate. . The concrete of claim 1, wherein the concrete impregnated with the corrosion inhibitor used in the pier pedestal and the pier is a mixture of sodium silicate powder and liquid silica sol in a weight ratio of 10: 0.5 to 1. Installation method of the prefabricated steel structure piers excellent corrosion resistance, characterized in that the mixture in the ratio of 100: 3-5. The method of claim 1, wherein the step of installing the corrosion preventing anode is to prepare a sacrificial anode and both ends of the sacrificial anode to install the sacrificial anode to be electrically connected to the outer surface of the bridge through the iron core. Excellent method of installing prefabricated steel structure piers. The method of claim 5, wherein the sacrificial anode is any one selected from zinc anode, zinc alloy anode, aluminum alloy anode, and magnesium alloy anode. The method of claim 1, wherein the installation of the corrosion preventing anode comprises preparing an insoluble anode for corrosion prevention, one end of the insoluble anode is connected to a positive pole of an external power source through a lead wire, and a negative pole of the external power source is connected. Corrosion resistance comprising connecting to the outer surface of the pier via another lead wire such that the insoluble anode is electrically connected to the outer surface of the pier via lead wires, external power and other lead wires, and then supplying anticorrosive current. How to install this excellent prefabricated steel structure piers. The method of claim 7, wherein the insoluble anode is any one selected from a platinum anode, a titanium anode, and a titanium-based platinum plating anode. The method of claim 1, wherein the installation of the corrosion preventing anode is to prepare a sacrificial anode and both ends of the sacrificial anode to install the sacrificial anode to be electrically connected to the outer surface of the bridge through the iron core, to prepare an insoluble anode One end of the insoluble anode is connected to a positive pole of an external power source through a lead wire, and a negative pole of the external power source is connected to an outer surface of a piers through another lead wire so that the insoluble anode is connected to the lead wire and an external power source. And installing it so as to be electrically connected to the outer surface of the bridge through another lead wire, and then supplying anticorrosive current. The method of claim 9, wherein the sacrificial anode is any one selected from zinc anode, zinc alloy anode, aluminum alloy anode and magnesium alloy anode, the insoluble anode is any one selected from platinum anode, titanium anode and titanium-based platinum anode. Installation method of the prefabricated steel structure piers excellent corrosion resistance.

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