An emulsified asphalt-cement-based coating and a method of preparation

Abstract

The present application relates to a kind of emulsified asphalt-cement-based coating technology for inducing marine sessile organism attachment, especially relates to a kind of emulsified asphalt-cement-based coating and preparation method, belongs to the cross field of marine sessile organism and marine engineering coating discipline.The material components of the present application are: cementing material, emulsified asphalt, sand, water, biological calcium powder, calcium carbonate powder, trace element, acrylic emulsion and superplasticizer.The present application can be applied to newly-built marine engineering, especially a large number of engineering in service in the ocean.It not only can improve the durability of reinforced concrete structure, and simply, economically realizes the repair of marine ecological environment.This not only greatly broadens the anticorrosion application of marine sessile organism in the reinforced concrete structure in service, but also can be widely applied to marine ecological environment repair engineering.

Description

An emulsified asphalt-cement based coating and its preparation method Technical Field

[0001] This invention relates to an emulsified asphalt-cement-based coating technology for inducing the attachment of marine sessile organisms, and more particularly to an emulsified asphalt-cement-based coating and its preparation method, belonging to the interdisciplinary field of marine sessile organisms and marine engineering coatings. Background Technology

[0002] In marine concrete structure corrosion protection technology, surface coating protection has become the most commonly used marine corrosion protection technology due to its economy and practicality. However, for marine concrete structures located in tidal zones and fully submerged zones, which are constantly wet due to tides or always submerged in water, general coatings cannot meet the requirements. Therefore, a coating that can be applied and cured directly in seawater or in humid environments is needed. Currently, although anti-corrosion coatings for underwater and humid interfaces such as polyester resin systems, ethylene resin systems, and epoxy resin systems have been developed, they have problems such as insufficient adhesion to the concrete interface, short service life, and high cost. In particular, concrete surfaces often have plant matter, microbial films, etc., which are highly sensitive to the adhesion surface of anti-corrosion coatings, but it is very difficult to clean these surfaces to a level suitable for anti-corrosion coating application.

[0003] Current research indicates that attached organisms such as oysters and barnacles can improve the impermeability of concrete surfaces, thereby enhancing the durability of marine concrete structures. The denser the attachment of these organisms, the more significant the protective effect. Utilizing marine attached organisms for corrosion protection is not only proactive, economical, and environmentally friendly, but also overcomes the limitations of current reinforced concrete corrosion protection technologies in tidal zones and underwater environments. However, in practical engineering, attached organisms are often affected by the external environment, resulting in sparse, loose, or even non-attached structures. Recent studies show that oyster attachment and growth are related to the substrate, with concrete being a preferred substrate. Adding calcareous materials such as bio-calcium carbonate powder, calcium carbonate powder, and gypsum powder to cement can increase the attachment of oyster larvae; similarly, oysters are more likely to attach to dark-colored substrates. For concrete structures already in service, demolishing and rebuilding to change the substrate is impractical. Treating the concrete surface and applying coatings to induce attached organisms is the most feasible approach. However, no relevant data has been found regarding coatings applied to concrete surfaces that induce the attachment of marine organisms, and their application in corrosion protection of reinforced concrete structures in marine environments. Therefore, there is a need to develop a coating that can rapidly increase the amount of marine organisms attached to concrete surfaces, particularly one that can quickly induce attachment and metamorphosis of these organisms and promote their long-term growth, while also being simple to apply and easy to use. This would significantly broaden the application scope of marine organisms in the corrosion protection of reinforced concrete.

[0004] CN104938384 describes an artificial reef experiment in which 10%–20% (by weight of cement) of 150–200 mesh bio-calcium carbonate powder (fish bones, coral, eggshells, and shell fragments in a 1:1:1:1 ratio) and shell fragments were simultaneously incorporated. The results showed that as the amount of calcium carbonate added increased, the induced biomass gradually increased, reaching its maximum at 20% of the cement weight. This also reduced the alkalinity of the concrete artificial reef surface, making it easier for microorganisms and algae to attach, increasing biomass and population size, and improving fish attraction. The precipitates from the bio-calcium carbonate cement mortar covering layer are harmless to the environment and organisms. While experiments on artificial reef construction and bioaccumulation using concrete mixed with bio-calcium carbonate powder and oyster shell fragments did enhance bioaccumulation, the primary bioaccumulated organisms were marine plants and microorganisms.

[0005] Meanwhile, the rapid economic development along the coast in recent decades, coupled with a lack of attention to environmental protection, has led to large-scale ecological damage along the coast, significantly impacting my country's coastal ecology and economy. The current series of national policies will usher in a peak period for marine engineering construction in my country. The large-scale construction of marine engineering projects and breakwaters to ensure the stability of the surrounding waters will further damage the already fragile marine ecosystem. Without appropriate ecological protection measures, this will inevitably bring even greater disasters to the coastal ecosystem. Furthermore, most coastal infrastructure cannot be dismantled, and the ecology of the surrounding waters requires restoration. This has led to the growing awareness that applying ecological technologies to large-scale infrastructure projects can effectively improve or restore the marine ecosystem. Therefore, constructing concrete projects with good ecological effects, or ecologicalizing existing concrete projects to improve the nearshore ecological environment, is crucial and urgent. However, to date, ecological technologies for breakwaters and other projects located in tidal zones remain largely undeveloped in China.

[0006] Oysters are "ecological engineers," primarily concentrated in tidal zones and within 30 meters of water depth. They readily attach to other oysters, forming thick oyster reefs. Therefore, dense oyster attachment to breakwaters contributes to the ecological restoration of these reefs. Furthermore, many oyster reefs are now severely damaged, requiring large-scale oyster reattachment for ecological restoration. Both marine ecological engineering and oyster reef restoration can leverage the large-scale reproduction of oysters to achieve their ecological functions. Consequently, there will be a significant demand for concrete-based oyster attachment substrates. Current domestic and international research on oyster attachment is as follows:

[0007] I. The Influence of Ions on the Attachment and Metamorphosis of Marine Sedentary Larvae

[0008] Domestic and international research on the attachment and metamorphosis induction of marine sessile larvae mainly focuses on the effects of ion concentration in solution, with K being one of the ions and substances studied in depth. + NH3, Ca 2+ and Cu 2+ The first three ions or substances can promote the attachment or metamorphosis of oysters at appropriate concentrations, but Cu... 2+ The promoting effect is not obvious, and at high concentrations, it may even increase the mortality rate of larvae. K + This induces larval metamorphosis by affecting cell membrane behavior; NH3 enters the cell, causing an increase in intracellular pH, which in turn causes depolarization of neurons in the behavioral pathway, thereby inducing fixation metamorphosis. Although numerous studies have been conducted on the attachment and metamorphosis of fixation organisms on various surfaces such as polyethylene sheets, shells, and tiles in solution, such methods are not easy to implement or are too costly in practical marine concrete engineering applications.

[0009] With the widespread application of concrete in marine engineering, especially in recent oyster reef restoration projects, concrete has become one of the most commonly used substrate materials for marine organism attachment. However, concrete differs significantly from traditional materials such as seashells, limestone, rubber tires, and plastic sheets. Concrete has high alkalinity, high calcium ion content, and contains abundant other ions, such as potassium and sodium ions, which greatly affect oyster attachment and growth. Although some oyster reef restoration projects have used newly manufactured concrete components and recycled concrete as substrates, the results have not been ideal.

[0010] II. The effects of concrete of different types of cement on marine plants and sessile organisms

[0011] Currently, almost all marine concrete engineering projects use silicate cement concrete, which has high alkalinity (the pH of the pore solution is generally between 12.0 and 13.0), while the pH of seawater is typically between 7.9 and 8.4. Due to the alkalinity gradient, concrete in contact with seawater continuously releases alkali, thereby raising the pH of the seawater in that area and disrupting the local ecosystem. This significantly inhibits the attachment and growth of organisms on its surface, especially alkalinity-sensitive organisms. Current domestic and international research shows that artificial reefs made of different cement types have significantly different effects on organism attachment. Artificial reefs made of aluminate cement and fly ash silicate cement have better organism attachment effects and lower alkalinity compared to ordinary silicate cement concrete. Similarly, adding 40%-60% fly ash and slag powder to cement concrete has better ecological effects. In addition, concrete with aggregate cementitious materials exhibits a greater variety and quantity of organisms attaching to it than cement concrete, and the higher the content of aggregate cementitious materials, the better the ecological effect. In the United States, eco-friendly concrete projects utilize low-alkalinity cement concrete, such as aluminate cement, particularly slag silicate cement, where slag powder replaces up to 50%, resulting in a better ecological effect of enriching marine plants and animals. Using lower-alkalinity cement to prepare concrete can effectively increase the biomass of alkali-sensitive organisms (mainly marine plants), but it has limited effect on increasing the amount and density of oyster attachment.

[0012] III. The Influence of Calcium on the Attachment of Marine Sessile Organisms

[0013] Domestic and international studies have shown that the chemical composition of the substrate significantly affects the attachment, metamorphosis, and subsequent growth of oyster larvae. The most commonly used calcium-containing substrates (limestone and concrete) effectively induce oyster larvae attachment, with an induction effect comparable to that of the shell. This indicates that calcium plays a crucial role in the attachment, metamorphosis, and growth of oyster larvae.

[0014] Recently, in addition to conventional substrates, researchers have studied the addition of calcium compounds to cement-based materials to increase the calcium content in concrete and investigate oyster larval attachment. Literature studies have used 80-mesh bone meal, calcium carbonate powder, and gypsum powder (at dosages of 62.5% and 37.5% of cement weight, respectively) as single additives in mortar for oyster attachment experiments. Under the same conditions, the order of the induction ability of calcium-containing forms for oyster larval attachment was: bone meal > calcium carbonate = calcium sulfate; the dosage of calcium carbonate powder ranged from 5% to 60% of the mortar weight (41.7% to 500.0% of the cement weight), with the best effect observed at a dosage of 20% (166.7% of the cement weight). Although the addition of bone meal, calcium carbonate powder, and gypsum powder can increase oyster attachment, the excessively high proportions (the weight of the calcium powder all exceeding 41.7% of the cement weight, even reaching 500.0%) severely affect the mechanical properties and durability of the concrete, making it unsuitable for use in concrete engineering in marine environments. Furthermore, while bone meal has a good inducing effect on oyster attachment, adding more than 10% of the cement will cause the concrete to mold. Therefore, although bone meal, calcium carbonate, and other calcareous substances are currently added to concrete, the impact of the marine environment on the durability of the concrete structure is not considered, making it unsuitable for use in harsh marine environments. Patent CN104529286, from a waste utilization perspective, proposes adding 10%–20% by weight of 5mm–8mm oyster shell fragments to artificial reefs to obtain concrete that does not affect bio-attachment and does not pollute the environment. While adding oyster shell fragments does enhance bioaccumulation, it primarily enriches marine plants and microorganisms.

[0015] In summary, calcium content is crucial for the attachment of oyster larvae, and current experimental results also demonstrate that adding an appropriate amount of calcium carbonate to cement-based materials can promote the attachment and growth of oyster larvae. However, cement concrete contains a large amount of calcium ions, and the pH value of the pore solution is generally greater than 12.5. The pH value of a saturated calcium hydroxide solution is about 12 at room temperature, so the calcium ion concentration in the concrete pore solution is approximately 5 mmol / L; while the solubility of calcium carbonate is very low, only 9.5 × 10⁻⁶ at 25℃. -5 mol / L (9.5×10 -2 (mmol / L). Currently, the optimal calcium ion concentration range for inducing shellfish attachment is considered to be 10–25 mmol / L. Even when oyster larvae are placed in a saturated calcium carbonate solution, there is insufficient calcium... 2+ The concentration provides suitable Ca for oyster attachment. 2+ Concentration. Furthermore, Ca(OH)₂ inside cement concrete can be released relatively quickly, while the dissolution of calcium carbonate requires a longer time. Therefore, it can be determined that adding calcium carbonate materials to concrete promotes the attachment of oyster larvae. 2+It does not play a leading role.

[0016] Furthermore, excessive amounts of shell powder, with the weight ratio of shell powder to cement exceeding 10% and sometimes even reaching 500%, have a significant impact on concrete durability. While appropriate amounts of calcium carbonate materials can maintain or even improve the impermeability of concrete, excessive amounts are highly detrimental to concrete's resistance to sulfuric acid and sulfate corrosion in seawater.

[0017] Therefore, there are still many problems with using calcium-based substances such as bio-calcium carbonate, bovine bone meal, and calcium carbonate powder to incorporate into concrete for inducing the attachment of marine sessile organism larvae, especially the problems caused by excessive calcium content in concrete performance and mold growth caused by the incorporation of bovine bone meal.

[0018] IV. The Influence of Color on the Attachment of Marine Sessile Organisms

[0019] Substrate color has a certain influence on the attachment, metamorphosis, and growth of marine sessile larvae. International studies have reported that dark substrates promote oyster growth in colder waters. Domestic research indicates that oyster larvae exhibit color selectivity. The color selectivity of Hong Kong giant oyster larvae for plastic substrates is: black > white > red. Long oyster larvae prefer to attach to black and gray plastic substrates, suggesting that black and gray may be a form of camouflage to avoid predators. Barnacles prefer to attach to red substrates. Pearl oysters also prefer dark (black, red) and non-reflective substrates, exhibiting photosensitive behavior. Furthermore, the bacteria *Alteromonas calwellii* attract oyster larvae by producing a compound involved in melanin synthesis.

[0020] Studies on the influence of substrate color on the attachment of marine sessile organism larvae have been limited to organic polymer boards such as plastic boards and polyethylene boards, as well as asbestos boards. While concrete is a promising alternative substrate, particularly for current oyster reef restoration, artificial ecological engineering construction, and corrosion protection of marine reinforced concrete, the impact of its color on the amount of sessile organism larvae attached has not yet been documented.

[0021] While current research has explored the effects of different substrates and colors on marine sessile organism attachment, and recently investigated the influence of incorporating calcareous materials into concrete on this process, there is currently no research on coatings that induce marine sessile organism attachment. However, surface treatment and application of sessile organism-inducing coatings to existing concrete structures and waste concrete can facilitate ecological restoration of marine engineering projects, representing a highly promising research direction in engineering ecology. This is particularly relevant for current oyster reef restoration, artificial ecological engineering construction, and corrosion protection of marine reinforced concrete. However, due to the involvement of knowledge from marine biology, marine microbiology, marine chemistry, and marine concrete engineering materials and structures, and the significant differences between these disciplines, interdisciplinary research faces numerous challenges. These include the unclear water-cement ratio of cement-based materials, the unclear mechanism of oyster attachment induced by calcareous materials, the severe durability deficiency caused by excessive calcium powder in cement, and the susceptibility of added bone meal to mold. Furthermore, professionals in marine concrete engineering materials and structures lack the specialized knowledge required for marine sessile organism attachment. Therefore, collaborative efforts from multiple disciplines are essential to address these challenges. Summary of the Invention

[0022] The purpose of this invention is to develop a coating that can be directly applied and cured in humid environments. This coating induces the rapid and dense adhesion of sessile organisms to the concrete surface, utilizing the adhesion characteristics of oysters to achieve a biological corrosion-resistant effect. Furthermore, the large-scale adhesion of these organisms can also purify water and restore the ecosystem. This addresses the problems of limited effectiveness, short service life, and high cost of corrosion protection measures in tidal and underwater areas of marine concrete engineering, as well as the urgent need for marine ecological restoration due to ecological degradation.

[0023] The objective of this invention is achieved by using low-alkalinity cementitious materials, acrylic emulsions, and superplasticizers, and by adding emulsified asphalt, modified bio-calcium powder, calcium carbonate powder, and trace elements to the coating. This results in an emulsified asphalt-cement-based coating that has a high ability to induce oyster larvae to attach and metamorphose, while also being able to be directly applied and cured in a humid environment. This achieves a uniform and dense oyster adhesion effect, utilizing the oyster's fixation characteristics to ensure the durability of the concrete structure, and without causing pollution to the marine environment.

[0024] The present invention also includes the following structural features:

[0025] Its material components are: cementitious materials, emulsified asphalt, sand, water, biological calcium powder, calcium carbonate powder, trace elements, acrylic emulsion and superplasticizer, with a weight ratio of 1: (0.4~0.8):(0.5~1.3):(0.10~0.30):(0.02~0.10):(0.02~0.10):(0.01~0.08):(0.08~0.15):(0.001~0.008).

[0026] Preferably, the bio-calcium powder is: bovine bone powder, and the bio-calcium carbonate powder includes one or more of oyster shell powder, fish bone powder, eggshell powder, and coral powder, with a fineness of 100 mesh to 1000 mesh.

[0027] Preferably, the bio-calcium powder is: eggshell powder, coral powder, oyster shell powder, and fish bone powder with a mesh size between 100 and 500 mesh, treated with one or two of the following acids, including acetic acid, acetic acid, silicic acid, and sulfurous acid; and bovine bone powder with a mesh size between 100 and 500 mesh, treated with one or two of the following acids, including diluted phosphoric acid, sulfuric acid, hydrochloric acid, and nitric acid.

[0028] Preferably, the trace elements zinc, iron, potassium, and phosphorus can be selected from natural minerals, industrial products, or chemical reagents, including one or more of zinc sulfate, calcium phosphate, zinc phosphate, potassium sulfate, potassium nitrate, ferric sulfate, ammonium nitrate, potassium phosphate, ammonium phosphate, and ferric phosphate, and modified to achieve the slow release of the corresponding ions and reduce or eliminate their adverse effects on concrete performance. However, for eutrophic areas, substances containing nitrogen and phosphorus are not selected.

[0029] Preferably, the calcium carbonate powder is one or more of the following: calcite, chalk, limestone, marble, aragonite, travertine powder, as well as processed light calcium carbonate, activated calcium carbonate, calcium carbonate whiskers, and ultrafine light calcium carbonate, with a fineness greater than 200 mesh.

[0030] Preferably, the acrylic emulsion is a polyurethane-modified emulsion.

[0031] Preferably, the emulsified asphalt is one of cationic emulsified asphalt or anionic emulsified asphalt. Its performance indicators are: evaporation residue content > 55%, 5-day stability ≤ 5%, and residue on a sieve (1.18mm sieve) ≤ 0.1%.

[0032] Preferably, the cementitious material is one of the following: silicate cement with added mineral admixtures, sulfoaluminate cement, and alkali-activated cementitious material. The mineral admixtures in the silicate cement include one or more combinations of silica fume, slag powder, and fly ash; the sulfoaluminate cement includes one or two of rapid-hardening sulfoaluminate cement, high-strength sulfoaluminate cement, and expansive sulfoaluminate cement; the alkali-activated cementitious material includes one of alkali-activated slag and alkali-activated slag + fly ash.

[0033] Preferably, the sand is one or more of the following: river sand, manufactured sand (parent rock may be limestone, basalt or granite), and sea sand with a particle size of 0.16mm to 2.36mm.

[0034] Preferably, the superplasticizer is one of polycarboxylic acid and naphthalene-based.

[0035] A method for preparing an emulsified asphalt-cement-based coating includes the following steps:

[0036] S1: Weigh emulsified asphalt, cementitious materials, sand, water, biological calcium powder, calcium carbonate powder, trace elements, acrylic emulsion and superplasticizer;

[0037] S2: Put the cementitious material, bio-calcium powder, calcium carbonate powder, trace elements and powdered superplasticizer into the mixer, with a speed of 1000-1500 rpm and a mixing time of 4-8 minutes;

[0038] S3: Then add the sand, adjust the speed to 500-1000 rpm, and mix for 2-5 minutes. Set aside.

[0039] S4: Mix acrylic emulsion, emulsified bitumen, and water thoroughly. Place the mixture together with the homogeneous material in a high-speed mixer at 200-500 rpm and stir for 5-10 minutes. This will produce an emulsified bitumen-cement-based coating with excellent induction effect for inducing and anchoring organisms on marine engineering surfaces.

[0040] Compared with the prior art, the beneficial effects of the present invention are:

[0041] Currently, there is a lack of green and economical methods for improving both the durability of marine concrete and the ecological aspects of marine concrete engineering. Oysters, as "ecological engineers" of the ocean, possess functions such as densifying concrete surface and improving the ecological environment. This invention proposes an emulsified asphalt-cement based coating that induces the attachment and metamorphosis of marine organisms, promoting long-term growth. It is also characterized by simple construction and ease of application. It can be applied to newly constructed marine engineering projects, especially those already in service in the ocean. It not only improves the durability of reinforced concrete structures but also achieves simple and economical restoration of the marine ecological environment. This significantly expands the application of marine sessile organisms in corrosion protection of existing reinforced concrete structures and can be widely used in marine ecological environment restoration projects. Detailed Implementation

[0042] The present invention will be described in detail below through embodiments. These embodiments are only used to illustrate the present invention and do not limit the scope of the present invention. Examples of coating formulations are as follows:

[0043] Example 1: The weight ratio of emulsified asphalt, cementitious material, sand, water, modified biological calcium powder (modified bovine bone powder: oyster shell powder = 2:1), calcium carbonate powder, zinc sulfate, acrylic emulsion and superplasticizer is 0.6:1:1:0.20:0.03:0.03:0.02:0.12:0.005.

[0044] Example 2: The weight ratio of emulsified asphalt, cementitious material, sand, water, modified biological calcium powder (modified bovine bone powder: oyster shell powder = 2:1), calcium carbonate powder, zinc sulfate, acrylic emulsion and superplasticizer is 0.6:1:1:0.20:0.05:0.05:0.04:0.12:0.005.

[0045] Example 3: The weight ratio of emulsified asphalt, cementitious material, sand, water, modified biological calcium powder (modified bovine bone powder: oyster shell powder = 2:1), calcium carbonate powder, zinc sulfate, acrylic emulsion and superplasticizer is 0.6:1:1:0.20:0.08:0.08:0.06:0.12:0.005.

[0046] Example 4: The weight ratio of emulsified asphalt, cementitious material, sand, water, modified biological calcium powder (modified bovine bone powder: oyster shell powder = 2:1), calcium carbonate powder, zinc sulfate, acrylic emulsion and superplasticizer is 0.6:1:1:0.20:0.08:0.08:0.02:0.12:0.005.

[0047] Example 5: The weight ratio of emulsified asphalt, cementitious material, sand, water, modified biological calcium powder (modified bovine bone powder: oyster shell powder = 2:1), calcium carbonate powder, zinc sulfate, acrylic emulsion and superplasticizer is 0.6:1:1:0.20:0.03:0.03:0.06:0.12:0.005.

[0048] Example 6: The weight ratio of emulsified asphalt, cementitious material, sand, water, modified biological calcium powder (modified bovine bone powder: oyster shell powder = 2:1), calcium carbonate powder, zinc sulfate, acrylic emulsion and superplasticizer is 0.6:1:1:0.20:0.03:0.03:0.04:0.12:0.005.

[0049] Example 7: The weight ratio of emulsified asphalt, cementitious material, sand, water, modified biological calcium powder (modified bovine bone powder: oyster shell powder = 2:1), calcium carbonate powder, zinc sulfate, acrylic emulsion and superplasticizer is 0.6:1:1:0.20:0.05:0.05:0.02:0.12:0.005.

[0050] Example 8: The weight ratio of emulsified asphalt, cementitious material, sand, water, modified biological calcium powder (modified bovine bone powder: oyster shell powder = 2:1), calcium carbonate powder, zinc sulfate, acrylic emulsion and superplasticizer is 0.6:1:1:0.20:0.08:0.08:0.04:0.12:0.005.

[0051] Example 9: The weight ratio of emulsified asphalt, cementitious material, sand, water, modified biological calcium powder (modified bovine bone powder: oyster shell powder = 2:1), calcium carbonate powder, zinc sulfate, acrylic emulsion and superplasticizer is 0.6:1:1:0.20:0.08:0.08:0.06:0.12:0.005.

[0052] Example 10: The weight ratio of emulsified asphalt, cementitious material, sand, water, modified biological calcium powder (modified bovine bone powder: oyster shell powder = 2:1), calcium carbonate powder, zinc sulfate, acrylic emulsion and superplasticizer is 0.6:1:1:0.20:0.03:0.05:0.02:0.12:0.005.

[0053] Method for modifying bovine bone meal: Add 100-mesh bovine bone meal to a 2% phosphoric acid solution at a weight ratio of 1:3. Stir at 20-30℃ for 30 minutes in a stirrer at 200-500 rpm. Centrifuge at 3000-5000 rpm for 3 minutes. Discard the supernatant and wash the centrifuged solid with water 2-3 times until the washing water is no longer acidic. Vacuum dry the centrifuged solid at 40℃. Mix the dried bovine bone meal with slag powder at a weight ratio of 1:4 and grind with a vibratory mill to a fineness greater than 200 mesh.

[0054] Modification method of zinc sulfate: Select diatomaceous earth with SiO2 content >90% and fineness of 600 mesh. Add 150g of water to a stirrer at 60℃, then add 100g of zinc sulfate and stir until completely dissolved. Set aside. Then heat 150g of the above diatomaceous earth to 60℃ and add it to the solution. Stir for 10 minutes in a stirrer at a speed of 200-500 rpm. Then dry in a drying oven at 100℃ to obtain modified zinc sulfate.

[0055] Compared with prior art document 1 (A biomimetic concrete artificial reef and its preparation method 2015CN104938384A), the difference is:

[0056] (1) The purpose of this invention differs from that of prior art document 1: Although prior art document 1 applies a layer of cement mortar mixed with ground oyster shells to the concrete surface, its purpose is mainly achieved through the biomimicry of the surface, attracting fish, microorganisms, and algae, increasing the number of microorganisms and improving the aquatic environment, without mentioning oysters. In contrast, the purpose of the emulsified asphalt-cement-based coating of this invention is to induce the attachment of attached organisms, mainly oysters, and to consider the attachment of barnacles when protecting reinforced concrete in tidal zones.

[0057] (2) Reference document 1 indicates that in cement mortar, the addition of bio-calcium carbonate powder (150-200 mesh) at less than 10% of the cement mass has no significant effect on induced adhesion. However, in the research process of this invention, modified bovine bone powder and bio-calcium carbonate powder were mixed to form emulsified asphalt-cement-based coating (fineness: 100-1000 mesh), and the optimal dosage of bovine bone powder and bio-calcium carbonate powder was found to be less than 10% of the cementitious material.

[0058] (3) Modification of bovine bone powder and biological calcium carbonate powder, specifically, eggshell powder, coral powder, oyster shell powder and fish bone powder with a mesh size of 100 to 500 mesh are treated with the following acids, including one or two of acetic acid, acetic acid, silicic acid and sulfurous acid; bovine bone powder with a mesh size of 100 to 500 mesh is treated with the following acids, including one or two of diluted phosphoric acid, sulfuric acid, hydrochloric acid and nitric acid.

[0059] (4) The prior art describes the difficulty of embedding oyster shells on concrete surfaces, and this method is not suitable for every engineering surface, resulting in low feasibility. The present invention achieves a good effect of inducing and attaching organisms by applying a layer of emulsified asphalt-cement-based coating to the concrete surface, without the need for embedding oyster shells. This not only simplifies the construction process but also significantly increases the amount of oysters attached.

[0060] (5) In recent years, there have been several instances of severe corrosion of artificial reefs in the marine environment. This is mainly caused by the combined effects of bio-sulfuric acid secreted by anaerobic microorganisms such as Thiobacillus and acidic substances secreted by other bacteria. Calcium carbonate has very weak resistance to acid corrosion; therefore, excessively high content of fine-grained calcium carbonate can lead to severe acid corrosion.

[0061] Compared with comparative document 2 (Fan Ruiliang. The Influence of Matrix Type on Oyster Attachment, Growth, Population Establishment and Reef Development [D]), the difference is as follows:

[0062] (1) Comparative document 2 used 80-mesh cow bone meal, calcium powder, and gypsum powder, which were added separately to the concrete. In this invention, all calcareous materials have a fineness greater than 100 mesh, which is greater than the fineness of the materials in comparative document 3. Modified cow bone meal was also added, and the particle size distribution and its inducing ability in the coating were taken into consideration.

[0063] (2) Under normal temperature conditions, when bovine bone meal is ground using a vibratory mill, the fineness exceeds 80 mesh, but due to the large amount of collagen in the bovine bone meal, severe agglomeration occurs, making further grinding impossible. This invention employs dilute acid modification technology and combines it with other substances for compound grinding, resulting in bovine bone meal with a fineness >200 mesh, modified bio-calcium powder. The prepared bio-calcium powder retains the original bio-calcium content, increases the release rate of substances that induce oyster larvae attachment, and reduces the amount of bio-calcium powder added, thereby minimizing its impact on coating performance.

[0064] (3) Because bovine bone powder contains a lot of collagen and other organic substances, the addition of a large amount of these substances will cause the coating strength and impermeability to decrease. In particular, when the amount exceeds 5%, the strength of the coating will decrease rapidly, the impermeability will deteriorate significantly, and it will grow mold under standard curing conditions.

[0065] This invention, through controlled use of dilute acid modification and composite grinding technology, fully utilizes the inducing ability of bovine bone meal, significantly reducing its dosage. Furthermore, it incorporates anti-corrosion treatment and modification to achieve a composite inducing agent primarily composed of bovine bone meal. Its dosage is small, having almost no impact on coating performance, while exhibiting strong oyster larvae adhesion ability and solving the problem of mold growth after coating application. Compared to coatings without the inducing agent, the number of oyster larvae adhering to concrete after application of the inducing agent is significantly increased.

[0066] Comparative studies and literature review indicate that calcium content is crucial for oyster larvae attachment. Similarly, some experimental results demonstrate that adding appropriate amounts of calcium carbonate to cement-based materials can promote oyster larvae attachment and growth. However, cement-based coatings contain a large amount of calcium ions, and the pH value of the pore solution is generally greater than 12.5. The pH value of a saturated calcium hydroxide solution at room temperature is approximately 12, with a calcium ion concentration of about 5 mmol / L. Meanwhile, the solubility of calcium carbonate is very low, only 9.5 × 10⁻⁶ at 25°C. -5 mol / L (9.5×10 -2 (mmol / L). Currently, the optimal calcium ion concentration range for inducing oyster attachment is considered to be 10–25 mmol / L. Even when oyster larvae are placed in a saturated calcium carbonate solution, there is insufficient calcium... 2+ The concentration provides a suitable ion concentration for oyster attachment. Furthermore, Ca(OH)₂ inside the coating can be released relatively quickly, while the dissolution of calcium carbonate requires a longer time. Therefore, it can be determined that incorporating calcium carbonate materials into the coating promotes the attachment of oyster larvae. 2+ It does not play a dominant role. Early attachment, metamorphosis, and HCO3 in oysters... - Related to, during metamorphosis and Ca 2+ Together, they form a secondary shell of calcium carbonate. After the addition of calcium carbonate, the calcium carbonate reacts with CO2 and water to form Ca(HCO3)2, which then participates in the attachment process. This is the fundamental mechanism by which it promotes the attachment of oyster larvae.

[0067] There is an optimal dosage of calcium carbonate in cement-based materials, which can be explained from the following three aspects:

[0068] 1) For equal-volume replacement of cement, as the calcium carbonate content increases, the alkali in the cementitious material is diluted, and the total alkalinity decreases. However, as the calcium carbonate content increases, the probability of calcium carbonate dissolving in the cementitious material increases, and the HCO3- content in the solution increases. - Increased content promotes the adhesion and metamorphosis of oysters; however, when the dosage is too high, the permeability of cement-based materials increases sharply, and the alkali and carbonate ions in them seep out rapidly, making the negative effects of alkali prominent, while the critical or negative effects of carbonate ions begin to appear, resulting in a decrease in the amount of adhesion.

[0069] 2) For equal-volume replacement aggregates, as the admixture dosage increases, the permeability of cementitious materials decreases, leading to an increase in calcium ions and OH groups. - While the exudation of calcium ions decreases, the permeation rate of carbonate ions will gradually increase. When it reaches a certain value, the oyster attachment reaches its maximum value. As the dosage continues to increase, the calcium ion concentration decreases significantly, and the carbonate concentration may also decrease. This results in calcium ion concentration limiting the attachment of oyster larvae, which manifests as a decrease in the amount of attachment.

[0070] 3) For equal-volume replacement mineral admixtures, permeability also increases with increasing admixture dosage. Furthermore, due to the increase in calcium carbonate, the required HCO3 content for oyster shell adhesion is reduced. - When the concentration reached a suitable range, it was observed that oyster larvae attached to the material more frequently. As the amount of mineral admixture continued to increase, the amount of mineral admixture decreased, resulting in increased leaching of alkali and carbonate ions. However, excessive alkali and HCO3... - Ions inhibit oyster larvae from attaching.

[0071] Compared with comparative document 3 (Li Zhenzhen, Gong Pihai, Guan Changtao, et al. Bioattachment effect of artificial reefs made of concrete with different cement types [J]. Advances in Fisheries Science, 2017, 38(5):57-63.), the difference is as follows:

[0072] Comparative document 3 used composite silicate cement, slag silicate cement, pozzolanic silicate cement, fly ash silicate cement, and aluminate cement. This invention employs a composite addition of ordinary silicate cement and mineral admixtures to achieve low-alkalinity cement. Silica fume is a highly active mineral admixture, and its appropriate dosage significantly improves the durability of reinforced concrete in marine environments. Through optimized design and experiments, low-alkalinity cement with excellent strength and durability can be obtained. Simultaneously, utilizing the high impermeability of silica fume concrete, even with high internal alkalinity, a large number of oyster larvae can still attach, metamorphose, and grow. Furthermore, the composite use of low-alkalinity sulfoaluminate cement regulates the alkalinity of the emulsified asphalt-cement-based coating, providing a suitable pH value for oyster larvae attachment. In addition, marine plants and attached organisms such as oysters and barnacles have different alkali tolerances and require different environments during the attachment and later stages. For example, barnacles and oysters require large amounts of calcium ions for attachment, metamorphosis, and later growth.

[0073] The concrete in Comparative Document 3 is used to enrich marine organisms, mainly based on the size and diversity of the attached biomass, with various algae being the primary attachment organisms. The research objective of this invention is to induce oyster attachment. However, oysters and barnacles are more tolerant of alkalinity than algae, and oyster attachment and metamorphosis require a large amount of calcium ions. Therefore, although the two cement-based materials appear to be the same, they are actually quite different.

[0074] Furthermore, the unique features of this invention and its beneficial effects are as follows:

[0075] Dark matter

[0076] Utilizing the light-avoidance properties of oyster eyedropper larvae, emulsified asphalt is incorporated into the coating to alter its color, making it darker. This allows the oyster larvae to perceive a dark environment, inducing them to reach the dark concrete surface and increasing the likelihood of contact between the larvae and the concrete, thus increasing the larval-induced attachment rate. Specifically:

[0077] Marine biologists, in their research on the attachment of marine sessile organisms to different colored substrates for purposes such as aquaculture and propagation or eliminating unwanted populations, have considered using different colored substrates. This falls under the discipline of marine biology, which is quite different from marine concrete engineering or concrete materials science—they are entirely separate disciplines. Through the intersection of marine sessile organisms and concrete science, a method for inducing oyster larvae attachment using dark-colored coatings has been developed. This invention uses emulsified asphalt to deepen the coating's color, thereby promoting oyster larvae attachment. The addition of other materials to the coating will affect its performance. This invention considers that coatings made with different types of cement have different colors. Therefore, the amount of dark-colored material added is determined based on the type and dosage of cement. Emulsified asphalt also affects the coating's performance. Most importantly, if the alkali and calcium content in the coating is not controlled while adding emulsified asphalt,… 2+ At isotonic rates, the released alkali affects the attachment, metamorphosis, and growth of attached organism larvae. Therefore, when the dosage exceeds a certain value, the amount of larvae attached decreases. This invention designs and controls the impermeability of emulsified asphalt-cement-based coatings, primarily through controlling the dosage and modifying the coating. As the dosage of the dark-colored substance increases, larval attachment initially increases. The larval attachment is highest when the dosage is 0.5%–6% of the cementitious material, but then increases slightly or remains unchanged.

[0078] Trace elements

[0079] Oysters accumulate high levels of zinc, far exceeding those found in the seawater they inhabit, and also contain significant amounts of iron, phosphorus, and potassium. Additionally, the solution contains a suitable concentration of zinc. 2+ K + Concentration can promote early attachment and metamorphosis of oyster larvae. Therefore, zinc sulfate, potassium sulfate, potassium nitrate, ferric sulfate, zinc phosphate, ammonium nitrate, potassium phosphate, ammonium phosphate, ferric phosphate, and calcium phosphate are used as trace elements and incorporated into the coating. Through modification of these substances, the strength and impermeability of the coating are kept essentially unchanged, resulting in a significant increase in the induced attachment rate of oyster larvae. Specifically:

[0080] Marine biologists, in order to clarify the attachment mechanism of oysters and for the purpose of aquaculture and propagation, study the attachment and metamorphosis of different ions on marine sessile organisms, which falls under the discipline of marine biology. This is quite different from marine concrete engineering or concrete materials science; they are entirely separate disciplines. Through the intersection of marine sessile organisms and concrete science, a method has been developed to induce oyster larvae to attach to concrete surfaces by adding appropriate substances to coatings. Because soluble salts have a significant impact on coating performance, such as affecting early workability, setting time, and later strength and impermeability, this invention uses diatomaceous earth as a carrier to fix these inorganic salts within the diatomaceous earth, reducing the impact of soluble salts on coating performance. At the same time, by utilizing the performance-enhancing effect of diatomaceous earth on emulsified asphalt-cement-based coatings, the good performance of emulsified asphalt-cement-based coatings can be maintained even when these inducing substances are added. In addition, because diatomaceous earth, as a carrier, has a slow-release effect, the release of soluble salts is slowed down, especially after immersion in seawater for a certain period of time, the release rate remains at a very low rate. Therefore, this part of the knowledge involves the intersection of marine sessile biology, chemistry and marine concrete engineering. Technical personnel in the fields of concrete and engineering or marine biology cannot obtain the technical features of this invention, which closely relate to the incorporation of trace elements into concrete, the alteration of the ion content of trace elements on the coating surface and the control of coating permeability, and the coating with a high ability to induce oyster larvae to attach, based on the existing background.

[0081] Coating penetration

[0082] The strength and permeability of coatings are crucial. Adding different inducers to cement-based coatings will affect their performance. Therefore, when considering adding different substances to promote oyster larvae attachment, metamorphosis, and later growth, it is essential to first control the overall impact on coating performance. Then, raw materials should be selected based on their compatibility. If the performance of raw materials does not meet the actual requirements, they should be modified before addition to achieve the desired function. However, while the aforementioned studies considered the effect of calcium content on oyster larvae attachment, they did not consider the coating's inherent performance, water-cement ratio, calcium content, or curing processes. Changes in coating permeability alter the rate of alkali and ion leakage. The worse the coating's impermeability, the greater the leakage rate of alkali and ions, potentially exponentially. Therefore, these released alkalis and ions can significantly impact larvae, potentially changing from promoting attachment to inhibiting it, especially with high cement content. Therefore, when adding inducers to coatings, it is essential to ensure that the changes in the coating's performance are within a controllable range, such as not exceeding 10%. Only in this way can the induction effects be compared; otherwise, it is impossible to evaluate the impact of single or combined addition of inducers on the induction effect on oyster larvae.

[0083] Only by understanding the optimal environment required for attachment, metamorphosis, and subsequent growth of marine sessile organisms, and by designing coatings based on their impermeability, rather than simply considering the dosage of various raw materials and ignoring the resulting changes in the coating's impermeability, can this knowledge be effectively integrated with the disciplines of marine sessile biology, chemistry, and marine concrete engineering. Technical personnel in either the concrete and engineering fields or the marine biology field cannot obtain the technical characteristics of the overall control of the coating's impermeability and the close connection between the inducing agent and the oyster's efficient induction of attachment through existing backgrounds.

[0084] Therefore, because this knowledge involves the intersection of marine sessile organisms, marine plants, and marine concrete engineering, those skilled in either the concrete and engineering fields or the marine biology fields cannot obtain, through prior art documents 1-2, the technical features of this invention—such as the color-changing effect of incorporating emulsified asphalt into the coating, modification with bone meal, grinding techniques, and control of coating permeability—which are closely related to the coating's highly efficient ability to induce oyster adhesion and its high durability. Furthermore, they cannot obtain, through prior art document 3, the technical features of this invention—such as the balance between reducing coating alkalinity and calcium ion concentration—which are closely related to the adhesion of marine sessile organisms.

[0085] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An emulsified asphalt-cement based coating, characterized in that: It is made of cementitious materials, emulsified asphalt, sand, water, modified bio-calcium powder, calcium carbonate powder, trace elements, acrylic emulsion, and superplasticizer. The weight ratio of cementitious materials, emulsified asphalt, sand, water, modified bio-calcium powder, calcium carbonate powder, trace elements, acrylic emulsion, and superplasticizer is as follows: 1:(0.4~0.8):(0.5~1.3):(0.10~0.30):(0.02~0.10):(0.02~0.10):(0.01~0.08): (0.08~0.15):(0.001~0.008); The modified bio-calcium powder is modified bovine bone powder and oyster shell powder; the fineness of the oyster shell powder is 100 mesh~1000 mesh; the modified bovine bone powder is prepared by adding 100-mesh bovine bone powder to a 2% phosphoric acid solution, with a weight ratio of 1:3, at a temperature of 20~30℃, and stirring for 30 minutes in a stirrer with a speed of 200~500 rpm, using a 3000~500 Centrifuge at 0 rpm for 3 minutes, discard the supernatant, and wash the centrifuged solid material 2-3 times with water until the washing water is no longer acidic. Vacuum dry the centrifuged solid material at 40℃. Mix the dried bone powder and slag powder at a weight ratio of 1:4, and grind them using a vibratory mill to a fineness greater than 200 mesh. The calcium carbonate powder is composed of calcite, chalk, limestone, marble, aragonite, travertine powder, activated calcium carbonate, calcium carbonate whiskers, and ultrafine lightweight carbon. The cementitious material is one or more of the following: calcium carbonate, with a fineness greater than 200 mesh; the emulsified asphalt is one of cationic emulsified asphalt or anionic emulsified asphalt; its performance indicators are: evaporation residue content > 55%, 5-day stability ≤ 5%, and sieve residue ≤ 0.1%; the cementing material is one of silicate cement with added mineral admixtures, sulfoaluminate cement, and alkali-activated cementing material; wherein the mineral admixtures in the silicate cement with added mineral admixtures include one or more combinations of silica fume, slag powder, and fly ash; sulfoaluminate cement includes one or two of rapid-hardening sulfoaluminate cement, high-strength sulfoaluminate cement, and expanded sulfoaluminate cement; the alkali-activated cementing material includes one of alkali-activated slag and alkali-activated slag + fly ash; the sand is one or more of river sand, manufactured sand, and sea sand with a particle size of 0.16mm~2.36mm; the superplasticizer includes one of polycarboxylic acid and naphthalene-based.