JP5437045B2 - Control method of composite deterioration of reinforced concrete - Google Patents

Description

  The present invention relates to improvement of durability of a concrete structure against combined deterioration of salt damage and alkali silica reaction.

  In recent years, there has been an increasing demand for improving the durability of concrete structures in the civil engineering and construction fields.

  The deterioration factors of concrete structures are diverse, but among them, one of the three major deterioration factors is salt damage and alkali silica reaction. In offshore structures, chloride ions permeate into reinforced concrete due to flying salt, and the reinforcing bars rust. On roads in cold regions, chloride ions penetrate into the interior by spraying anti-freezing agents such as sodium chloride and potassium chloride. At this time, Na and K ions penetrate into the reinforced concrete at the same time as chloride ions, so that an alkali silica reaction is often induced depending on the quality of the aggregate blended in the concrete. That is, in a concrete structure under such an environment, not only salt damage alone but complex deterioration with alkali silica reaction is likely to occur.

  In the case where salt damage or alkali silica reaction occurs independently, a method for suppressing the salt damage has been proposed. As a method for suppressing chloride ion penetration into the hardened concrete and imparting chloride ion penetration resistance, a method of reducing the water / cement ratio is known (see Non-Patent Document 1).

  A method of adding nitrite and nitrite-type hydrocalumite has been proposed for the purpose of rust prevention of reinforcing bars (see Patent Documents 1 to 3). Nitrite shows rust prevention effect, but does not show blocking effect of chloride ions entering from the outside, and nitrite type hydrocalumite shows rust prevention effect, but this is not mixed The cemented hardened body is likely to be porous, but rather to allow permeation of chloride ions from the outside.

  As a method for preventing corrosion of the reinforcing bars, a sacrificial anode material type cathodic protection method using a difference in standard electrode potential of metal is known. There are features such as no need for external electrodes, easy maintenance, and excellent long-term corrosion resistance (see Patent Document 4).

  On the other hand, the alkali silica reaction occurs when alkali silica gel is generated by a chemical reaction between an alkali hydroxide in a cement / concrete pore solution and an alkali-reactive mineral in an aggregate, and expands with water absorption.

  As a method for suppressing the alkali silica reaction, a method of adding an alkali silica reaction inhibitor and a method of impregnating or coating concrete are proposed (see Patent Documents 5 to 7). However, conventional alkali-silica reaction inhibitors are not effective, are used in large amounts, and are not practical from the viewpoint of economy.

  Zeolite is an aluminosilicate-based crystalline compound, and is a wide variety. There are various industrial utilization methods of zeolite, and utilization methods such as a catalyst, a humidity control material, a molecular sieve, an adsorbent, and an ion exchanger can be mentioned. Applications differ if the composition and crystal structure of the zeolite are different.

  However, an effective suppression method is not known for complex deterioration in which salt damage and alkali silica reaction occur simultaneously, and when the sacrificial anode material is used in combination with a specific lithium zeolite, the effect of suppressing the alkali silica reaction is reduced. It has not been known at all that it is effective for promoting or enhancing the effect of inhibiting salt damage and effective for combined deterioration of salt damage and alkali silica reaction.

  The present inventors have found that by installing a sacrificial anode material inside a concrete hardened body containing a specific lithium zeolite, an excellent suppression effect can be obtained for the combined deterioration of salt damage and alkali silica reaction. .

Koichi Kishitani, Noriaki Nishizawa et al., “Durability series of concrete, salt damage (I)”, Gihodo Publishing, pp. 59-63, May 1986

JP-A-53-003423 Japanese Patent Laid-Open No. 01-103970 Japanese Patent Laid-Open No. 04-154648 Japanese Patent No. 3099830 Japanese Patent Laid-Open No. 10-167781 JP 2006-62892 A JP 2006-89334 A

  The present invention provides a method for imparting excellent rust prevention effect and alkali silica reaction suppression effect to reinforced concrete, and improving resistance to complex deterioration due to salt damage and alkali silica reaction.

According to the present invention, (1) a sacrificial anode material is installed inside concrete hardened by mixing lithium-type zeolite, cement, and water, and the generation of non-conductive anodes around the sacrificial anode material is avoided. the electrolyte solution having a pH of 12 or higher and attaching a porous material containing, Ri Na electrically connecting the sacrificial anode material and concrete interior of the steel material, the sacrificial anode material, zinc, aluminum, and magnesium A method for suppressing composite deterioration of reinforced concrete due to salt damage and alkali silica reaction , wherein the lithium type zeolite is an EDI type, ABW type or a heat-treated product thereof, which is an alloy containing one or more selected from the group consisting of , especially the (2) heat treatment temperature of the lithium-type zeolite, in the case of EDI type 200 to 700 ° C., a heat treatment product in the case of ABW type 300 to 650 ° C. And, method for inhibiting complex deterioration of reinforced concrete (1), the content of lithium (3) lithium-type zeolite, is at least 5% by weight Li 2 _O in terms of reinforced concrete (1) or (2) (4) Composite deterioration of reinforced concrete according to any one of (1) to (3), wherein the total content of Na ₂ O and K ₂ O in the lithium zeolite is 0.5% by mass or less. (5) The method for suppressing composite deterioration of reinforced concrete according to any one of (1) to (4), wherein lithium zeolite is 1 to 20 parts by mass with respect to 100 parts by mass of cement, (6) Porous (1) The method for suppressing composite deterioration of reinforced concrete according to any one of (1) to (5), wherein the material contains an alkali silica reaction inhibitor, and (7) the alkali silica reaction inhibitor contains lithium ions. Comprising a composite method of inhibiting degradation of reinforced concrete (6).

  INDUSTRIAL APPLICABILITY The present invention provides reinforced concrete with an excellent rust prevention effect and alkali silica reaction suppression effect, and has an effect of improving resistance to complex deterioration due to salt damage and alkali silica reaction.

Hereinafter, the present invention will be described in detail.
In the present invention, “parts” and “%” are based on mass unless otherwise specified.
The concrete referred to in the present invention is a general term for cement paste, mortar, and concrete.

Here, the lithium type zeolite will be described. Among lithium-type zeolites, lithium-type zeolite having a Si / Al atomic ratio of 1 is preferable because the effect of suppressing the alkali silica reaction is large. As the lithium type zeolite having a Si / Al atomic ratio of 1, there are EDI type, ABW type and LTA type.
Of these, EDI type and ABW type can be synthesized easily by using allophane or kaolinite as a raw material and allowing an aqueous lithium hydroxide solution to act at less than 100 ° C.
On the other hand, synthesis of LTA requires hydrothermal treatment under pressure conditions exceeding 100 ° C., and it is difficult to directly synthesize LTA containing lithium. Lithium is supported by an ion exchange reaction after obtaining a type zeolite by hydrothermal synthesis. For this reason, it is difficult to completely replace sodium with lithium, and LTA may not provide a sufficient alkaline silica reaction suppression effect. Therefore, in the present invention, it is preferable to select the EDI type and the ABW type.

  The EDI-type zeolite is a general term for zeolites having a structure similar to a compound called Edingtonite.

  ABW-type zeolite containing lithium was named after being first reported by Barrer and White (Barrer RM and White ED, J. Chem. Soc., 1951, 1267). .

  As a method for synthesizing a lithium zeolite, a method using silica sol and alumina sol as starting materials (T. Matsumoto et al., Journal of the European Ceramic Society, 26, pp. 455-458, 2006) has been known. It has been. In addition, a method of reacting lithium hydroxide with allophane as a raw material is also known (Yusuke Okino et al., Abstracts of the 112th Academic Lecture Meeting of the Society of Inorganic Materials, pp. 8-9, 2006).

In the present invention, lithium-type zeolite synthesized by any method can be used, and includes those obtained by heat-treating lithium-type zeolite.
The heat treatment temperature varies depending on the zeolite. For example, in the case of EDI type, it is preferable that it is 200-700 degreeC. When the lithium-containing EDI-type zeolite is heat-treated at 200 to 700 ° C., it changes into an amorphous substance. That is, the crystal structure of the EDI-type zeolite is maintained up to 200 ° C., and the crystal changes from amorphous to 200 ° C. or more. And although it is in an amorphous state up to 700 ° C., when it exceeds 700 ° C., it crystallizes and changes to eucryptite.
In the case of the ABW type, 300 to 650 ° C. is preferable. When ABW type zeolite containing lithium is heat-treated at 300 to 650 ° C., it is changed to anhydrous ABW type zeolite. That is, the crystal structure of the ABW type zeolite is maintained up to 300 ° C., and when the temperature exceeds 300 ° C., the crystal structure changes to a completely different crystal structure to become an anhydrous ABW type zeolite. And it is in the state of anhydrous ABW type zeolite up to 650 ° C., but when it exceeds 650 ° C., it changes to γ-eucryptite. And when it heats further, it changes to (beta) -eucryptite at 900-1000 degreeC.
If the heat treatment conditions are not within the above temperature range, there may be a case where a sufficient effect of suppressing expansion due to alkali-silica reaction or a salt damage suppressing effect cannot be obtained.

The heat treatment referred to in the present invention is not particularly limited, but usually means a treatment such as drying or baking. As a specific method, for example, after allophane is reacted in an aqueous lithium hydroxide solution to form a lithium-type zeolite, a predetermined heat treatment may be performed at the stage of the drying operation. After drying under the above conditions, heat treatment may be performed again under predetermined conditions. The time for the heat treatment is not particularly limited, but is preferably about 5 minutes to 24 hours, and more preferably 10 minutes to 12 hours. If the reaction time is less than 5 minutes, the reaction in which the EDI-type zeolite changes to an amorphous substance or the reaction in which the ABW-type zeolite changes to anhydrous ABW may not proceed sufficiently. It may become.
The drying device is not particularly limited, and a drum dryer, a shelf dryer, a cylindrical dryer, a rotary kiln, an electric furnace, or the like can be used.

The lithium content of the lithium-type zeolite of the present invention is not particularly limited, but is usually preferably 5% or more and more preferably 7% or more in terms of Li ₂ O. The maximum amount of lithium that can be supported from the theoretical value at which the Si / Al atomic ratio is 1 can be calculated as 13.5%. If the lithium content is less than 5%, there may be a case where a sufficient effect of suppressing expansion due to alkali silica reaction cannot be obtained.

The content of sodium or potassium in the lithium zeolite of the present invention is not particularly limited, but usually, the total amount of Na ₂ O and K ₂ O is preferably 0.5% or less, 0.3 % Or less is more preferable. When the total amount of Na ₂ O and K ₂ O exceeds 0.5%, there may be a case where a sufficient effect of suppressing expansion due to the alkali silica reaction cannot be obtained.

  The amount of the lithium-type zeolite used in the present invention is preferably 1 to 20 parts, more preferably 5 to 15 parts, relative to 100 parts of cement. If it is less than 1 part, the effect of the present invention, that is, the suppression effect of expansion due to alkali silica reaction and the suppression effect of salt damage may not be sufficiently obtained, and if it exceeds 20 parts, further enhancement of the effect cannot be expected, The compressive strength may be reduced.

The specific surface area of the lithium-type zeolite of the present invention is not uniquely determined and is not particularly limited, but is usually in the range of ² to 200 m ² / g in terms of BET specific surface area.

  As the cement, various portland cements such as normal, early strength, super early strength, low heat, and moderate heat, various mixed cements in which blast furnace slag, fly ash, or silica is mixed with these portland cements, limestone powder and blast furnace slow Portland cement such as filler cement mixed with fine powder of cold slag, etc., and environmentally friendly cement (eco-cement) manufactured using municipal waste incineration ash and sewage sludge incineration ash as raw materials are listed. Or 2 or more types can be used.

  The water / binder ratio of the present invention is preferably 25 to 70%, more preferably 30 to 65%. Here, the binder means the total of cement and lithium type zeolite. When the water / binder ratio is less than 25%, pumpability and workability are lowered, cracking due to self-shrinkage is likely to occur, and salt damage resistance may be lowered. On the other hand, if it exceeds 70%, the amount of voids in the cured body increases, and salt damage resistance may decrease.

  In the present invention, the respective materials may be mixed at the time of construction, or a part or all of them may be mixed in advance.

  As the mixing device, any existing device can be used, and for example, a tilting mixer, an omni mixer, a Henschel mixer, a V-type mixer, and a Nauta mixer can be used.

  In the present invention, in addition to cement and lithium-type zeolite, fine aggregate such as sand, coarse aggregate such as gravel, expansion material, water reducing agent, AE water reducing agent, high performance water reducing agent, high performance AE water reducing agent, antifoaming Agents, thickeners, conventional rust inhibitors, antifreeze agents, shrinkage reducers, polymer emulsions, setting modifiers, clay minerals such as bentonite, anion exchangers such as hydrotalcite, granulated blast furnace slag powder and blast furnace It is possible to use together 1 type, or 2 or more types of the group which consists of admixtures, such as slag, such as slow-cooled slag fine powder, and limestone fine powder, in the range which does not inhibit the objective of this invention substantially.

  In the present invention, by installing a sacrificial anode material inside a hardened concrete body that is blended with lithium-type zeolite, cement, and water and hardened, the suppression effect of alkali silica reaction is promoted, and salt damage is suppressed. The effect is enhanced, and combined deterioration due to salt damage and alkali silica reaction can be greatly suppressed.

  In the present invention, the reinforcing bar in the concrete is used as a cathode, a sacrificial anode material is installed in the concrete, and the two are electrically connected to each other, thereby supplying an anticorrosion current to the reinforcing bar and preventing the reinforcing bar from being corroded. Here, the sacrificial electrode material refers to a material that contains a metal that has a higher ionization tendency than iron and that prevents corrosion of the reinforcing bars by ionization prior to iron.

  Examples of the metal constituting the sacrificial anode material include an alloy containing one or more selected from the group consisting of zinc, aluminum, and magnesium.

  In order to avoid passivation of the sacrificial anode material, it is necessary to keep the surroundings of the metal at a sufficient pH. For example, in the case of a zinc-aluminum alloy, the pH value needs to be 13.3 or more, and the pH value for suppressing passivation is different depending on the metal used, but the pH value is preferably 12 or more.

  Since the pH of the electrolyte solution contained in the porous material attached around the sacrificial anode material is high, there is a concern about the alkali silica reaction in the concrete portion adjacent to the porous material. Therefore, it is preferable that an alkaline silica reaction inhibitor is present in the electrolyte solution.

  The alkali silica reaction inhibitor is preferably lithium ions in order to avoid a decrease in pH of the electrolyte solution, and it is preferable to add lithium hydroxide, lithium carbonate, or lithium-type zeolite.

  The method of electrically connecting the reinforcing bar and the sacrificial anode material is not particularly limited as long as the reinforcing bar and the metal constituting the sacrificial anode material are electrically connected to each other. A method of embedding a part of the metal in the metal in the sacrificial anode material and winding it around a reinforcing bar is practically simple.

  In the present invention, after partially filling the concrete structure, the sacrificial anode material is installed and electrically connected to the reinforcing bar, or the sacrificial anode material and the reinforcing bar are electrically connected, and then the concrete is cast. An electrolyte solution having a pH sufficient to avoid the formation of a non-conductive coating on the metal surface, in which a concrete structure is constructed by embedding the sacrificial anode material, or the metal and the reinforcing bar are electrically connected. After covering with a porous material containing, the concrete is placed and the concrete structure is constructed by embedding the sacrificial anode material, so that an anticorrosion current flows between the sacrificial anode material and the reinforcing bar, and the reinforcing bars in the concrete are Corrosion protection.

In the present invention, the anticorrosion effect of the reinforcing bars can be confirmed by measuring the potential.
When a metal having a lower standard electrode potential is electrically connected to the reinforcing bar in the concrete, the potential of the reinforcing bar itself is lowered. Therefore, the effectiveness can be judged from the numerical value by measuring the potential.
The electric potential is measured using the lead verification electrode with the surface where the sacrificial anode material of the reinforcing bar in the concrete is installed as the measurement point. At this time, the sacrificial anode material and the reinforcing bar can be disconnected, and the instant-off potential immediately after the disconnection and the potential after 24 hours (off-potential after 24 hours) are measured and recovered from these differences. Calculate the extreme amount. The greater the amount of depolarization, the greater the effect of preventing corrosion of the reinforcing bars.

  Hereinafter, although an example and a comparative example are given and the contents are explained in detail, the present invention is not limited to these.

"Example 1"
10 parts of lithium zeolite shown in Table 1 was mixed with 100 parts of cement to prepare a concrete (mortar) having a water / binder ratio of 50%, and a 10 × 10 × 40 cm specimen was prepared. A reinforcing bar was placed in the center of the specimen in the axial direction, and a sacrificial anode material I was installed inside the specimen. Lead wires were connected to the reinforcing bar and sacrificial anode material, respectively, so that the electrical connection could be turned on and off outside the concrete specimen.
On the surface where the sacrificial anode material inside the concrete is installed, the point corresponding to the center of the reinforcing bar is taken as the measurement point, the lead-off reference electrode is used to measure the instant-off potential and the off-potential after 24 hours. The amount was calculated. Except when measuring the amount of depolarization, the rebar and the sacrificial anode material were electrically connected. In addition, the rust prevention effect, compressive strength, and chloride ion penetration depth were investigated. The results are also shown in Table 1.

<Materials used>
Lithium type zeolite A: Lithium-containing EDI type zeolite (Li-EDI), Li ₂ O content 7.1%, total content of Na ₂ O and K ₂ O 0.5%, BET specific surface area 50 m ² / g .
Lithium type zeolite B: Lithium-containing ABW type zeolite (Li-ABW), Li ₂ O content 9.0%, total content of Na ₂ O and K ₂ O 0.4%, BET specific surface area 40 m ² / g .
Lithium-type zeolite C: amorphous substance obtained by heat-treating lithium-containing EDI-type zeolite (Li-EDI) at 400 ° C., Li ₂ O content 9.0%, Na ₂ O and K ₂ O content Total 0.3%, BET specific surface area 30 m ² / g.
Lithium type zeolite D: anhydrous Li-ABW obtained by heat-treating lithium-containing ABW type zeolite (Li-ABW) at 400 ° C., Li ₂ O content 10.8%, Na ₂ O and K ₂ O Total content 0.1%, BET specific surface area 20 m ² / g.
Commercially available alkaline silica reaction inhibitor (1): Ca-type zeolite Commercially available alkaline silica reaction inhibitor (2): Lithium nitrite aqueous solution (concentration 30%)
Cement: Ordinary Portland cement, Commercial sand: Sanucitic pyroxene andesite, measured according to JIS A 1145 (chemical method). The amount of dissolved silica was 750 mmol / l, and the decrease in alkali concentration was 200 mmol / l.
Water: Tap water sacrificial anode material I: Zinc block covered with porous mortar containing LiOH as alkali silica reaction inhibitor (pH = 13.5)

<Measurement method>
Alkali-silica reactivity test (mortar bar method): Measured according to JIS A 1146. Those having a length change rate of less than 0.100% were judged to have an inhibitory effect on alkali silica reaction, and those having a length change rate of 0.100% or more were judged to have no inhibitory effect.
Rust prevention effect: Sodium chloride was added to the concrete (mortar) as an internal chloride ion so as to be 10 kg / m ^{3 in} terms of chloride ion. The specimen was heated to 40 ° C. to promote the corrosion of the reinforcing bars, and the presence or absence of rusting of the reinforcing bars was confirmed. The case where rust did not occur in the reinforcing bars was good, the case where rust occurred within an area of 1/10 was acceptable, and the case where rust occurred beyond an area of 1/10 was deemed impossible.
Depolarization amount: At 6 months of age, using a lead verification electrode, the instant-off potential immediately after disconnecting the electrical connection between the reinforcing steel inside the concrete and the sacrificial anode material, and OFF 24 hours after 24 hours have elapsed after cutting The potential was measured, and the amount of repolarization was calculated by the following equation.
Depolarization amount (mV) = [Eio (mV)] − [Eof (mV)]
Eio: Instant-off potential Eof: Off-potential compressive strength after 24 hours: Compressive strength at 28 days of age was measured according to JIS R 5201.

<Synthesis of lithium-type zeolite>
Lithium-type zeolite was synthesized by hydrothermal synthesis using allophane and lithium hydroxide as raw materials. At this time, the Li ₂ O / Al ₂ O ₃ molar ratio is 2.0, the SiO ₂ / Al ₂ O ₃ molar ratio is 1.73, the reaction temperature is 60 or 90 ° C., the reaction time is 24 hours, The reaction was carried out with stirring. The obtained composite was separated into solid and liquid, washed with warm water at 60 ° C., and dried at 70 ° C. Allophane was used in an amount of 10 kg, and lithium hydroxide was dissolved in water. The lithium hydroxide solution was 100 kg. As a result of identifying the synthesized product by powder X-ray diffractometry (XRD), it was an EDI type zeolite when the reaction temperature was 60 ° C. When the reaction temperature was 90 ° C., it was ABW type zeolite.

<Materials used>
Allophane: water-purified product from Tochigi Prefecture, commercial product, SiO ₂ content 33.6%, Al ₂ O ₃ content 33.1%, Fe ₂ O ₃ content 2.3%, CaO content Amount 0.4%, MgO content 0.1%, Na ₂ O content 0.03%, K ₂ O content 0.02%, ignition loss 30.1%
Lithium hydroxide: Commercial water: Tap water

  From Table 1, it can be seen that according to the present invention, the alkali silica reaction is suppressed, the rust prevention effect is high, and the effect of suppressing the combined deterioration due to salt damage and the alkali silica reaction is high. Moreover, it turns out that the synergistic effect by a combination is remarkable rather than the case where the effect of each of lithium type zeolite and sacrificial anode material is added together.

"Example 2"
As shown in Table 2, the same procedure as in Example 1 was performed except that the amount of lithium zeolite A used was changed with respect to 100 parts of cement. The results are also shown in Table 2.

  From Table 2, it can be seen that according to the present invention, the alkali silica reaction is suppressed, the rust prevention effect is high, and the effect of suppressing the combined deterioration of salt damage and alkali silica reaction is high.

"Example 3"
As shown in Table 3, the same procedure as in Example 1 was performed except that the sacrificial anode material was changed. In addition, it carried out similarly using the conventional antirust material for the comparison. The results are also shown in Table 3.

<Materials used>
Sacrificial anode material II: zinc aluminum alloy (pH = 13.5) covered with porous mortar containing LiOH as an alkali silica reaction inhibitor and having a zinc / aluminum ratio of 1/1
Sacrificial anode material III: Aluminum lump (pH = 13.5) covered with porous mortar containing LiOH as an alkali silica reaction inhibitor
Sacrificial anode material IV: Magnesium lump (pH = 12.0) covered with porous mortar containing LiOH as an alkali silica reaction inhibitor
Sacrificial anode material V: Zinc magnesium alloy (pH = 13.5) covered with porous mortar containing LiOH as an alkali silica reaction inhibitor and having a zinc / magnesium ratio of 1/1
Sacrificial anode material VI: Aluminum magnesium alloy (pH = 13.5) covered with porous mortar containing LiOH as an alkali silica reaction inhibitor and having an aluminum / magnesium ratio of 1/1
Sacrificial anode material VII: Zinc-aluminum-magnesium alloy (pH = 13.8) covered with porous mortar containing LiOH as an alkaline silica reaction inhibitor and having a zinc / aluminum / magnesium ratio of 1/1/1
Commercially available rust preventive material A: Lithium nitrite Commercially available rust preventive material B: Nitrite type hydrocalumite

  From Table 3, it can be seen that according to the present invention, the alkali silica reaction is suppressed, the rust prevention effect is high, and the effect of suppressing the combined deterioration of salt damage and alkali silica reaction is high.

  The present invention provides reinforced concrete with an excellent rust prevention effect and alkali silica reaction suppression effect, and improves resistance to combined deterioration due to salt damage and alkali silica reaction, such as marine structures and road slabs in cold regions. Suitable for use.

Claims (7)

A sacrificial anode material is placed inside concrete hardened by mixing lithium-type zeolite, cement, and water, and has a pH of 12 or more to avoid the formation of anode non-conduction around the sacrificial anode material. one electrolyte solution additionally provided a porous material containing, Ri Na electrically connecting the sacrificial anode material and concrete inside the steel, the sacrificial anode material, zinc, selected from the group consisting of aluminum, and magnesium Or it is an alloy containing 2 or more types, and lithium type zeolite is EDI type, ABW type, or these heat-treated products, The suppression method of the composite deterioration of a reinforced concrete by salt damage and alkali silica reaction. The suppression of composite deterioration of reinforced concrete according to claim 1, wherein the heat treatment temperature of the lithium type zeolite is 200 to 700 ° C in the case of EDI type and 300 to 650 ° C in the case of ABW type. Method. The content of lithium of the lithium-type zeolite is 5 wt% or more Li 2 _O terms method for inhibiting complex deterioration of reinforced concrete according to claim 1 or 2. The total content of Na 2 _O and K _{2 O} of the lithium-type zeolite is less than 0.5 wt%, method of inhibiting complex deterioration of reinforced concrete according to any one of claims 1 to 3. The method for suppressing composite deterioration of reinforced concrete according to any one of claims 1 to 4, wherein the lithium-type zeolite is 1 to 20 parts by mass with respect to 100 parts by mass of cement. The method for suppressing composite deterioration of reinforced concrete according to any one of claims 1 to 5, wherein the porous material contains an alkali silica reaction inhibitor. The method for suppressing composite deterioration of reinforced concrete according to claim 6, wherein the alkali silica reaction inhibitor contains lithium ions.