High-strength corrosion-resistant concrete and its use in marine engineering

Abstract

The application relates to the technical field of concrete, in particular to high-strength corrosion-resistant concrete and application of the high-strength corrosion-resistant concrete in marine engineering. The high-strength corrosion-resistant concrete comprises the following raw material components in parts by weight: 80-120 parts of Portland cement, 150-200 parts of broken stone, 100-150 parts of sand, 80-100 parts of bentonite, 10-20 parts of calcium carbonate, 5-10 parts of corrosion-resistant agent, 5-10 parts of water-reducing agent and 60-100 parts of water. The concrete has corrosion resistance, high strength and good permeability resistance, so the concrete has wide application prospects in marine engineering.

Description

Technical Field

[0001] This invention relates to the field of concrete technology, specifically to a high-strength corrosion-resistant concrete and its application in marine engineering. Background Technology

[0002] Marine engineering refers to the construction and maintenance of engineering projects carried out in the marine environment, including offshore oil and gas development, offshore wind power, marine transportation, and marine fisheries. Due to the corrosiveness, humidity, and strong winds and waves of seawater, the building materials used in marine engineering need to be durable, corrosion-resistant, and high-strength.

[0003] The use of traditional concrete in marine engineering has at least the following problems: (1) the compressive strength of concrete is insufficient, making it difficult to meet the requirements of marine engineering for high-strength materials; (2) the salt and corrosive substances in seawater will erode the surface of concrete, leading to a decrease in concrete durability. Therefore, the development of a high-strength, corrosion-resistant concrete is of great value for its application in marine engineering. Summary of the Invention

[0004] In order to solve at least one of the technical problems pointed out in the prior art, the present invention first provides a high-strength corrosion-resistant concrete.

[0005] The above-mentioned technical problem to be solved by the present invention is achieved through the following technical solution:

[0006] The present invention first provides a high-strength corrosion-resistant concrete, which comprises the following raw material components in parts by weight: 80-120 parts of silicate cement; 150-200 parts of crushed stone; 100-150 parts of sand; 80-100 parts of bentonite; 10-20 parts of calcium carbonate; 5-10 parts of corrosion inhibitor; 5-10 parts of water-reducing agent; and 60-100 parts of water.

[0007] The present invention firstly provides a new type of concrete with a high compressive strength through an optimized formula; secondly, by adding an anti-corrosion agent to the concrete, the concrete also has anti-corrosion properties.

[0008] Preferably, the high-strength corrosion-resistant concrete comprises the following raw material components in parts by weight: 90-110 parts silicate cement; 180-200 parts crushed stone; 120-150 parts sand; 80-90 parts bentonite; 10-15 parts calcium carbonate; 5-8 parts corrosion inhibitor; 5-8 parts water-reducing agent; and 80-90 parts water.

[0009] Most preferably, the high-strength corrosion-resistant concrete comprises the following raw material components in parts by weight: 100 parts silicate cement; 180 parts crushed stone; 120 parts sand; 90 parts bentonite; 15 parts calcium carbonate; 8 parts corrosion inhibitor; 7 parts water-reducing agent; and 80 parts water.

[0010] Preferably, the water-reducing agent is selected from naphthalene-based high-efficiency water-reducing agents.

[0011] Preferably, the bentonite is modified bentonite.

[0012] Preferably, the modified bentonite is prepared by the following method:

[0013] (1) Add bentonite to water, then add sodium lignosulfonate and stir until uniform to obtain bentonite dispersion;

[0014] (2) Add lithium nitrate and magnesium nitrate to the bentonite dispersion, stir for 20-40 min, add sodium carbonate, continue stirring for 1-2 h, and then separate the solid.

[0015] (3) After calcining the solid at 1300-1400℃ for 1-2 hours, the calcined powder is taken to obtain the modified bentonite.

[0016] The inventors made a surprising discovery during their research: adding modified bentonite prepared by the above method to the high-strength anti-corrosion concrete of this invention can significantly improve the impermeability of the high-strength anti-corrosion concrete of this invention compared to adding unmodified bentonite.

[0017] More preferably, in step (1), the ratio of bentonite, sodium lignosulfonate, and water is 10:1~3:80~120.

[0018] Most preferably, the ratio of bentonite, sodium lignosulfonate and water in step (1) is 10:2:100.

[0019] More preferably, in step (2), the weight ratio of bentonite dispersion to lithium nitrate, magnesium nitrate and sodium carbonate is 2000-3000:10-15:12-18:10-15.

[0020] Most preferably, in step (2), the weight ratio of bentonite dispersion to lithium nitrate, magnesium nitrate and sodium carbonate is 2500:14:15:13.

[0021] Preferably, in step (3), the solid is calcined at 1350°C for 1.5 hours, and the calcined powder is taken to obtain the modified bentonite.

[0022] The present invention also provides an application of the above-mentioned high-strength corrosion-resistant concrete in marine engineering.

[0023] Beneficial Effects: This invention firstly provides a novel concrete composition, which, through an optimized formula, exhibits high compressive strength. Secondly, by adding an anti-corrosion agent, the concrete also possesses anti-corrosion properties. Furthermore, the addition of modified bentonite prepared by the method described in this invention to the high-strength anti-corrosion concrete significantly improves its impermeability compared to adding unmodified bentonite. Because the concrete of this invention possesses anti-corrosion properties, high strength, and good impermeability, its application in marine engineering has broad prospects. Detailed Implementation

[0024] The present invention will be further explained below with reference to specific embodiments, but the embodiments do not limit the present invention in any way.

[0025] The corrosion inhibitor used in the following examples is the Three Lions brand FMA-H anti-permeability and corrosion resistant agent. All other raw materials were obtained by those skilled in the art through conventional purchasing channels.

[0026] Example 1: Preparation of High-Strength Corrosion-Resistant Concrete

[0027] Raw material composition by weight: Silicate cement (type PO42.5) 100 parts; Crushed stone 180 parts; Sand 120 parts; Bentonite 90 parts; Calcium carbonate 15 parts; Corrosion inhibitor 8 parts; Water-reducing agent 7 parts; Water 80 parts;

[0028] Preparation method: Mix the above raw materials evenly to obtain the high-strength corrosion-resistant concrete.

[0029] Example 2: Preparation of High-Strength Corrosion-Resistant Concrete

[0030] Raw material composition by weight: Silicate cement (type PO42.5) 100 parts; Crushed stone 180 parts; Sand 120 parts; Modified bentonite 90 parts; Calcium carbonate 15 parts; Corrosion inhibitor 8 parts; Water-reducing agent 7 parts; Water 80 parts;

[0031] The modified bentonite was prepared by the following method:

[0032] (1) Add bentonite to water, then add sodium lignosulfonate and stir until uniform to obtain bentonite dispersion; wherein, the ratio of medium bentonite, sodium lignosulfonate and water is 10:2:100.

[0033] (2) Add lithium nitrate and magnesium nitrate to the bentonite dispersion, stir for 30 min, add sodium carbonate, continue stirring for 1.5 h, and then separate the solid; wherein the weight ratio of bentonite dispersion to lithium nitrate, magnesium nitrate and sodium carbonate is 2500:14:15:13.

[0034] (3) After calcining the solid at 1350℃ for 1.5h, the calcined powder is taken to obtain the modified bentonite.

[0035] Preparation method: Mix the above raw materials evenly to obtain the high-strength corrosion-resistant concrete.

[0036] Example 3: Preparation of High-Strength Corrosion-Resistant Concrete

[0037] Raw material composition by weight: Silicate cement (type PO42.5) 80 parts; Crushed stone 150 parts; Sand 150 parts; Modified bentonite 80 parts; Calcium carbonate 20 parts; Corrosion inhibitor 5 parts; Water-reducing agent 5 parts; Water 60 parts;

[0038] The modified bentonite was prepared by the following method:

[0039] (1) Add bentonite to water, then add sodium lignosulfonate and stir until uniform to obtain bentonite dispersion; wherein, the ratio of medium bentonite, sodium lignosulfonate and water is 10:1:80.

[0040] (2) Add lithium nitrate and magnesium nitrate to the bentonite dispersion, stir for 20 min, add sodium carbonate, continue stirring for 1 h, and then separate the solid; wherein, the weight ratio of bentonite dispersion to lithium nitrate, magnesium nitrate and sodium carbonate is 2000:10:18:15.

[0041] (3) After calcining the solid at 1400℃ for 1 hour, the calcined powder is taken to obtain the modified bentonite.

[0042] Preparation method: Mix the above raw materials evenly to obtain the high-strength corrosion-resistant concrete.

[0043] Example 4: Preparation of High-Strength Corrosion-Resistant Concrete

[0044] Raw material composition by weight: Silicate cement (type PO42.5) 120 parts; Crushed stone 200 parts; Sand 100 parts; Modified bentonite 100 parts; Calcium carbonate 10 parts; Corrosion inhibitor 10 parts; Water-reducing agent 10 parts; Water 100 parts;

[0045] The modified bentonite was prepared by the following method:

[0046] (1) Add bentonite to water, then add sodium lignosulfonate and stir until uniform to obtain bentonite dispersion; wherein, the ratio of medium bentonite, sodium lignosulfonate and water is 10:3:120.

[0047] (2) Add lithium nitrate and magnesium nitrate to the bentonite dispersion, stir for 40 min, add sodium carbonate, continue stirring for 2 h, and then separate the solid; wherein the weight ratio of bentonite dispersion to lithium nitrate, magnesium nitrate and sodium carbonate is 2000:15:12:10.

[0048] (3) After calcining the solid at 1300℃ for 2 hours, the calcined powder is taken to obtain the modified bentonite.

[0049] Preparation method: Mix the above raw materials evenly to obtain the high-strength corrosion-resistant concrete.

[0050] Comparative Example 1: Preparation of High-Strength Corrosion-Resistant Concrete

[0051] Raw material composition by weight: Silicate cement (type PO42.5) 100 parts; Crushed stone 180 parts; Sand 120 parts; Modified bentonite 90 parts; Calcium carbonate 15 parts; Corrosion inhibitor 8 parts; Water-reducing agent 7 parts; Water 80 parts;

[0052] The modified bentonite was prepared by the following method:

[0053] (1) Add bentonite to water, then add sodium lignosulfonate and stir until uniform to obtain bentonite dispersion; wherein, the ratio of medium bentonite, sodium lignosulfonate and water is 10:2:100.

[0054] (2) Add lithium nitrate to the bentonite dispersion, stir for 30 min, add sodium carbonate, continue stirring for 1.5 h, and then separate the solid; wherein the weight ratio of bentonite dispersion to lithium nitrate and sodium carbonate is 2500:19:13.

[0055] (3) After calcining the solid at 1350℃ for 1.5h, the calcined powder is taken to obtain the modified bentonite.

[0056] Preparation method: Mix the above raw materials evenly to obtain the high-strength corrosion-resistant concrete.

[0057] The difference between Comparative Example 1 and Example 2 is that Comparative Example 1 only added lithium nitrate in the modification step (2) of modified bentonite; while Example 2 added both lithium nitrate and magnesium nitrate in the modification step (2) of modified bentonite.

[0058] Comparative Example 2: Preparation of High-Strength Corrosion-Resistant Concrete

[0059] Raw material composition by weight: Silicate cement (type PO42.5) 100 parts; Crushed stone 180 parts; Sand 120 parts; Modified bentonite 90 parts; Calcium carbonate 15 parts; Corrosion inhibitor 8 parts; Water-reducing agent 7 parts; Water 80 parts;

[0060] The modified bentonite was prepared by the following method:

[0061] (1) Add bentonite to water, then add sodium lignosulfonate and stir until uniform to obtain bentonite dispersion; wherein, the ratio of medium bentonite, sodium lignosulfonate and water is 10:2:100.

[0062] (2) Add magnesium nitrate to the bentonite dispersion, stir for 30 min, add sodium carbonate, continue stirring for 1.5 h, and then separate the solid; wherein the weight ratio of bentonite dispersion to magnesium nitrate and sodium carbonate is 2500:19:13.

[0063] (3) After calcining the solid at 1350℃ for 1.5h, the calcined powder is taken to obtain the modified bentonite.

[0064] Preparation method: Mix the above raw materials evenly to obtain the high-strength corrosion-resistant concrete.

[0065] The difference between Comparative Example 2 and Example 2 is that Comparative Example 2 only added magnesium nitrate in the modification step (2) of the modified bentonite; while Example 2 added both lithium nitrate and magnesium nitrate in the modification step (2) of the modified bentonite.

[0066] The high-strength anti-corrosion concrete prepared in Examples 1-4 and Comparative Examples 1-2 was tested for compressive strength and hydrostatic pressure after 28 days of curing following construction; the test results are shown in Table 1.

[0067] Table 1. Test results of the high-strength corrosion-resistant concrete of the present invention.

[0068] compressive strength Anti-seepage pressure High-strength corrosion-resistant concrete prepared in Example 1 88.7MPa 1.1MPa High-strength corrosion-resistant concrete prepared in Example 2 96.1MPa 2.5MPa High-strength corrosion-resistant concrete prepared in Example 3 90.8MPa 2.2MPa High-strength corrosion-resistant concrete prepared in Example 4 94.4MPa 2.4MPa High-strength corrosion-resistant concrete prepared in Comparative Example 1 91.7MPa 1.3MPa High-strength corrosion-resistant concrete prepared in Comparative Example 2 93.3MPa 1.4MPa

[0069] As can be seen from the experimental results in Table 1, the high-strength corrosion-resistant concretes prepared in Examples 1 to 4 all have high compressive strength.

[0070] As can be seen from the experimental results in Table 1, the high-strength anti-corrosion concrete prepared in Example 1 achieved a seepage pressure of 1.1 MPa, indicating that the high-strength anti-corrosion concrete of this invention also has good impermeability. The experimental results in Table 1 also show that the high-strength anti-corrosion concrete prepared in Example 2 has a significantly higher seepage pressure than the high-strength anti-corrosion concrete prepared in Example 1; this indicates that adding modified bentonite prepared by the method described in this invention to the high-strength anti-corrosion concrete of this invention can significantly improve its impermeability compared to adding unmodified bentonite.

[0071] The experimental results in Table 1 also show that, although the impermeability pressure of the high-strength anti-corrosion concrete prepared in Comparative Examples 1 and 2 is higher than that of the high-strength anti-corrosion concrete prepared in Example 1, the increase is much smaller than that of the high-strength anti-corrosion concrete prepared in Example 2. This indicates that the modification method of the modified bentonite in this invention is crucial; only modified bentonite obtained by simultaneously adding lithium nitrate and magnesium nitrate in modification step (2) can significantly improve the impermeability of the high-strength anti-corrosion concrete of this invention; while modified bentonite obtained by only adding lithium nitrate or only adding magnesium nitrate in modification step (2) cannot significantly improve the impermeability of the high-strength anti-corrosion concrete of this invention.

Claims

1. A high-strength corrosion-resistant concrete, characterized by, The raw material components comprise the following parts by weight: 80-120 parts silicate cement; 150-200 parts crushed stone; 100-150 parts sand; 80-100 parts modified bentonite; 10-20 parts calcium carbonate; 5-10 parts corrosion inhibitor; 5-10 parts water-reducing agent; 60-100 parts water; The modified bentonite was prepared by the following method: (1) Add bentonite to water, then add sodium lignosulfonate and stir until homogeneous to obtain bentonite dispersion; (2) Add lithium nitrate and magnesium nitrate to the bentonite dispersion, stir for 20-40 min, add sodium carbonate, continue stirring for 1-2 h, and then separate the solid. (3) After calcining the solid at 1300~1400℃ for 1~2h, the calcined powder is taken to obtain the modified bentonite.

2. The high-strength corrosion-resistant concrete according to claim 1, characterized by, It contains the following raw material components in parts by weight: 90-110 parts silicate cement; 180-200 parts crushed stone; 120-150 parts sand; 80-90 parts modified bentonite; 10-15 parts calcium carbonate; 5-8 parts corrosion inhibitor; 5-8 parts water-reducing agent; and 80-90 parts water.

3. The high strength corrosion resistant concrete according to claim 1, wherein, The raw material components include the following parts by weight: 100 parts silicate cement; 180 parts crushed stone; 120 parts sand; 90 parts modified bentonite; 15 parts calcium carbonate; 8 parts corrosion inhibitor; 7 parts water-reducing agent; and 80 parts water.

4. The high-strength corrosion-resistant concrete according to claim 1, characterized by, In step (1), the ratio of bentonite, sodium lignosulfonate and water is 10:1~3:80~120.

5. The high-strength corrosion-resistant concrete according to claim 1, wherein In step (1), the ratio of bentonite, sodium lignosulfonate and water is 10:2:

100.

6. The high strength corrosion resistant concrete according to claim 1, wherein, In step (2), the weight ratio of bentonite dispersion to lithium nitrate, magnesium nitrate and sodium carbonate is 2000~3000:10~15:12~18:10~15.

7. The high-strength corrosion-resistant concrete according to claim 6, characterized in that, In step (2), the weight ratio of bentonite dispersion to lithium nitrate, magnesium nitrate and sodium carbonate is 2500:14:15:

13.

8. The high-strength corrosion-resistant concrete according to claim 1, characterized in that, In step (3), the solid is calcined at 1350°C for 1.5 hours, and the calcined powder is taken to obtain the modified bentonite.

9. The application of the high-strength corrosion-resistant concrete according to any one of claims 1 to 8 in marine engineering.