CN115466083A

CN115466083A - Cement wood concrete and preparation method and application thereof

Info

Publication number: CN115466083A
Application number: CN202111367264.7A
Authority: CN
Inventors: 崔恒香
Original assignee: Shanghai Jiangye Garden Landscape Engineering Co ltd; Jiangsu Xiangye Building Material Technology Co ltd
Current assignee: Shanghai Jiangye Garden Landscape Engineering Co ltd; Jiangsu Xiangye Building Material Technology Co ltd
Priority date: 2021-06-11
Filing date: 2021-11-18
Publication date: 2022-12-13

Abstract

The invention discloses cement wood concrete and a preparation method and application thereof. The cement wood concrete comprises cement, water, wood aggregate and an additive; the surface of the wood aggregate is provided with a layer of anticorrosive hydrophobic film. The anti-corrosion hydrophobic film is formed by soaking the wood aggregate in an anti-corrosion hydrophobic agent, wherein the anti-corrosion hydrophobic agent comprises wood vinegar. The wood aggregate soaked by the anti-corrosion water repellent can be directly applied to cement concrete without rotting and expansion, so that the cement wood concrete can be really applied. The cement wood concrete can adopt wood aggregate prepared from plant wastes, has the performances of pressure resistance, fracture resistance, crack resistance, light weight, alkali resistance, heat preservation, water permeability and the like, and is a green environment-friendly material with excellent performance.

Description

Cement wood concrete and preparation method and application thereof

Technical Field

The invention relates to the field of green environment-friendly building materials, in particular to cement wood concrete and a preparation method and application thereof.

Background

A large amount of plant wastes are generated during tree trimming, wood processing and crop harvesting, the plant wastes comprise waste branches, waste tree roots, rice hulls, furniture leftover materials, wood chips and the like, plants are renewable resources, and the plant wastes are adopted to form aggregate in cement wood concrete, so that a large amount of sand and stone materials are saved in the cement concrete, and the natural ecological environment is protected.

Concrete is a commonly used building material, which is made of a gel material, aggregates (sand, gravel) and water in a proper proportion and then hardened for a certain period of time.

In order to reasonably apply the plant wastes, the inventor of the application is dedicated to research and develop the cement wood concrete, the plant wastes can be used as the aggregate in the cement wood concrete, and the cement wood concrete also has excellent performances of compression resistance, fracture resistance, crack resistance, alkali inhibition, light weight, heat preservation, water permeability and the like, so that the plant wastes are changed into valuable, a large number of resources are saved, and the pressure of the plant wastes on solid wastes in urban and rural treatment and ecological environment is relieved.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, the present invention is to provide a cement-wood concrete using plants or plant wastes as aggregates, which has excellent properties such as compression resistance, fracture resistance, crack resistance, alkali resistance, light weight, heat preservation, and water permeability.

The wood aggregate mainly comprises three components of cellulose, hemicellulose and lignin, and the three substances are tightly combined together in the cell wall of the plant to form different shapes, structural rigidity and solubility. Wherein, the hydrogen bonds among cellulose molecules form a rigid structure of cellulose chains, a plurality of cellulose chains form microfibrils through the hydrogen bonds and Van der Waals force, and substances such as hemicellulose, lignin and the like are filled among the cellulose microfibrils. The cellulose microfibrils play a rigid role in the wood aggregate, the lignin plays a role in enhancing the mechanical strength of the wood aggregate and resisting the attack of adverse external environment in the wood aggregate, and the hemicellulose plays a filling role.

The wood aggregate may be cut or crushed from plants or plant waste. The wood aggregate comprises wood coarse aggregate, wood fine aggregate, wood fiber or any mixture thereof. The wood coarse aggregate comprises wood strips, wood chips, bamboo strips and bamboo chips or any mixture thereof, the wood fine aggregate comprises wood chips, ground rice flour or a mixture thereof, and the wood fiber comprises linear wood fiber.

The wood aggregate is applied to the concrete because the wood aggregate is easy to rot and expand when contacting with water in the concrete, and the performance of the concrete is not lower than or even better than that of the common cement concrete, so that the problem that the wood aggregate is easy to rot and expand needs to be solved. One of the solutions is to pretreat the wood aggregate before applying it to concrete, so that it has the characteristics of corrosion resistance and expansion resistance. Therefore, it is important to find a suitable method for pretreating wood aggregate and imparting anti-corrosion and anti-swelling properties to the wood aggregate.

The wood aggregate may be pretreated by an acid or alkaline process. However, strong acid has high toxicity and corrosiveness, and can cause large negative effects on the environment in the treatment process, while alkali treatment can cause peeling reaction of cellulose or hemicellulose, and can weaken the rigidity effect of the wood aggregate. Therefore, neither strong acids nor bases are suitable for pretreatment of wood aggregates.

The inventors have discovered that wood aggregate is highly susceptible to swelling problems during the formation of cement-wood concrete because wood readily absorbs water and thereby becomes bulky. In order to overcome the water absorption and expansion of the wood aggregate, through a large number of researches and experiments, the inventor finally finds that the weak acid can precipitate the lignin from the surface of the wood to some extent and is not easy to fall off into the solution, and the lignin is slowly adsorbed to the surface of the wood in the precipitation process, so that a compact film body is formed on the surface of the wood, and the water is prevented from being soaked into the wood.

After extensive testing, it was found that wood aggregate was less prone to decay and swelling after being placed in wood vinegar for soaking for a period of time than wood aggregate that was not soaked in wood vinegar. The wood aggregate soaked in the wood vinegar is observed under a microscope, and the observation shows that the surface of the wood aggregate soaked in the wood vinegar has a film, and the film can isolate the wood aggregate from water, so that the wood aggregate is resistant to the invasion of moisture and bacteria, and is not easy to rot and expand. The wood vinegar is weak acid, can be extracted in the production process of charcoal, can also be produced by wastes such as rice hulls, coconut shells, straws and the like, and is environment-friendly and low in price. The wood vinegar has certain bactericidal and insecticidal effects, and the main components of the wood vinegar comprise water, organic acids, phenols, alcohols, ketones and the like, so the wood vinegar is widely used as pesticide or fertilizer.

Therefore, the wood vinegar is finally selected as the pretreatment material of the wood aggregate, which not only can prevent the wood aggregate from swelling and rotting when meeting water, but also can play a certain role in pest control and harm prevention.

Accordingly, in a first aspect the present invention provides a cementitious wood concrete comprising cement, water, wood aggregate and an admixture; the surface of the wood aggregate is provided with a layer of anti-corrosion hydrophobic film.

Further, the anti-corrosion hydrophobic film is formed by soaking the wood aggregate in an anti-corrosion hydrophobic agent, and the anti-corrosion hydrophobic agent comprises wood vinegar.

Furthermore, the antiseptic water repellent also comprises chitosan and/or sodium alginate.

Preferably, the anti-corrosion water repellent consists of wood vinegar and chitosan, and the weight ratio of the wood vinegar to the chitosan is (10-100) to (1-5).

Preferably, the anti-corrosion water repellent consists of wood vinegar, chitosan and sodium alginate, wherein the weight ratio of the wood vinegar to the chitosan to the sodium alginate is (10-100): (1-5): (0.5-1), preferably 100.

Further, the soaking time is 1 to 15 days, preferably 1 to 3 days, and more preferably 3 days.

Further, the moisture content of the wood aggregate is 12% -15%.

Further, the wood aggregate comprises one or more of the following materials: wood coarse aggregate, wood fine aggregate and wood fiber; wherein the wood coarse aggregate comprises one or more of the following materials: wood strips, wood chips, bamboo strips and bamboo chips, wherein the size of the wood coarse aggregate is preferably less than 10cm, and more preferably 1cm to 5cm; the wood fine aggregate comprises one or more of the following materials: crushed materials of wood chips and rice husk; the wood fibers comprise linear wood fibers, and the length of the linear wood fibers is preferably 3-6cm.

Further, the weight ratio of the cement, the water, the wood aggregate and the admixture is (35-45): 40-65): 1-2) of 100.

Preferably, the wood aggregate comprises wood coarse aggregate and wood fine aggregate, and the weight ratio of the wood coarse aggregate to the wood fine aggregate is (2-4): 1.

Further, the admixture comprises one or more of: concrete water reducing agent, concrete retarder, concrete accelerator and concrete emulsion agent.

Further, the cement wood concrete also comprises fly ash or silica fume, and is used for adsorbing harmful substances.

Further, the cement wood concrete also comprises sand and/or gravel.

Preferably, the cement wood concrete comprises cement, water, wood aggregate, fly ash and a concrete emulsion agent, wherein the weight ratio of the cement, the water, the wood aggregate, the fly ash and the concrete emulsion agent is 100 (40-45): (40-55): 5-10): 1-2), the wood aggregate is a mixture of wood coarse aggregate and wood fine aggregate, and the weight ratio of the wood coarse aggregate to the wood fine aggregate is (2-4): 1.

Preferably, the cement wood concrete comprises cement, water, wood aggregate, fly ash and concrete emulsion agent, wherein the weight ratio of the cement, the water, the wood aggregate, the fly ash and the concrete emulsion agent is 100 (35-40): (50-65): 5-10): 1-2, and the wood aggregate is wood coarse aggregate.

In a second aspect, the invention provides an anti-corrosion water repellent which comprises pyroligneous liquor.

Preferably, the anti-corrosion water repellent consists of wood vinegar and chitosan, wherein the weight ratio of the wood vinegar to the chitosan is (10-100) to (1-5).

Preferably, the anti-corrosion water repellent consists of wood vinegar, chitosan and sodium alginate, wherein the weight ratio of wood vinegar to chitosan to sodium alginate is (10-100): (1-5): 0.5-1), preferably 100.

Furthermore, the anti-corrosion water repellent also comprises water, and the weight ratio of the wood vinegar to the water is (1-10): 100.

In a third aspect, the invention provides a wood aggregate soaked with the anti-corrosive water repellent.

The fourth aspect of the invention provides a preparation method of cement wood concrete, which comprises the following steps:

step 1, wetting the surface of the wood aggregate soaked by the anti-corrosion water repellent;

and 2, mixing and stirring the wood aggregate, the cement, the admixture and the water uniformly to obtain the cement wood concrete.

Further, fly ash can be added in the step 2.

Furthermore, in the step 2, an antiseptic water repellent waste liquid can also be added. The waste liquid of the anti-corrosion water repellent is a solution remained after wood aggregate is soaked, a large amount of lignin with colloid exists in the waste liquid of the anti-corrosion water repellent, and the strength of concrete can be improved by adding the waste liquid into the concrete.

Further, the weight ratio of the cement, the water, the wood aggregate, the fly ash and the additive is 100 (40-45): 40-55): 5-10): 1-2, the wood aggregate is a mixture of wood coarse aggregate and wood fine aggregate, and the weight ratio of the wood coarse aggregate and the wood fine aggregate is 2-4): 1.

Furthermore, the weight ratio of the cement, the water, the wood aggregate, the fly ash and the additive is (35-40): (50-65): (5-10): 1-2), and the wood aggregate is wood coarse aggregate.

A fifth aspect of the invention provides the use of a cement wood concrete as described above for the manufacture of roads, concrete bricks, concrete walls, flower pots, flower stands, flower boxes, railings, curbstones and stools.

Further, the concrete bricks comprise concrete planting bricks, concrete hollow bricks and concrete solid bricks.

The invention also provides application of the cement wood concrete on a wall painting layer and a ground leveling layer.

The cement wood concrete provided by the invention at least has the following technical effects:

1. the cement wood concrete can change plant wastes into valuables, and the plant wastes are used as aggregates, so that about 1.5 tons of sandstone aggregates can be saved in per cubic meter of concrete, resources are saved, and the cement wood concrete is a novel environment-friendly and energy-saving building material.

2. The wood aggregate is easy to corrode and expand when meeting water and bacteria and cannot be directly applied to cement concrete, however, after the wood aggregate is treated by pyroligneous liquor, an anti-corrosion hydrophobic film is formed on the surface of the wood aggregate, so that the wood aggregate cannot expand and corrode when meeting water. As for the principle of forming the anti-corrosion hydrophobic membrane, one guess is that because lignin is separated out from the pyroligneous liquor and then remains on the surface of the wood aggregate, the membrane formed by the higher adsorption capacity resists the invasion of moisture and bacteria to the wood aggregate, so that the wood aggregate cannot expand due to the invasion of water molecules and cannot corrode due to the invasion of bacteria. It is also speculated that the main components of the wood vinegar liquid are water, organic acid, phenols, alcohols, ketones and other substances, which can permeate into the surface of the garden waste to perform hydrolysis reaction with protein and starch on the surface of the garden waste, and the product after the hydrolysis reaction is adsorbed on the surface of the garden waste to form a film, so as to form a hydrophobic polymer.

3. The anti-corrosion hydrophobic film can enable the surface of the wood aggregate to be rough, and when the wood aggregate is applied to concrete, the wood aggregate can form an occlusion force when being gelled with cement, so that the strength of the concrete is improved.

4. After the chitosan is added into the anticorrosion water repellent, the chitosan is easy to form a cationic gene with positive charge in an organic acid solution, has good adsorbability, hygroscopicity, fiber forming property, film forming property and the like, has a stable effect on an organic solvent, can effectively solidify a carrier, and improves the effect of adsorbing the anticorrosion water repellent on the surface of the wood aggregate to form a film; in addition, sodium alginate is added into the anticorrosive water repellent, and the sodium alginate has good permeability and viscosity in organic acid, so that the film structure on the surface of the wood aggregate has plasticity, and the film structure can be prevented from cracking; in the mixture of the antiseptic and water repellent, wood vinegar liquid plays a leading role, and chitosan and sodium alginate play a role in improving performance.

5. A large amount of lignin with colloid exists in the waste liquid of the anticorrosion water repellent after the pretreatment of the wood aggregate, and the waste liquid can be added into concrete, so that the strength of the concrete can be improved, and the problem of waste liquid retreatment is solved.

6. The wood aggregate in the cement wood concrete can adsorb free alkali in the concrete, so that the alkali is not easy to dissociate to the surface of the concrete, and the water permeability of the concrete and the growth environment of wood are ensured.

7. The cement wood concrete has the performances of compression resistance, earthquake resistance, bending resistance, crack resistance, alkali inhibition, moisture preservation, sound absorption, water permeability and the like, and is a green environment-friendly material with excellent performance; the material has certain breaking strength and can be used as a plate; the material has heat preservation and moisture retention performances, and can be used as a wall body and a road base material, so that the humidity and the temperature in the air can be adjusted; the wood aggregate can be used as a wall material of a river channel, and the wood aggregate has a bacteriostatic action after being treated, so that the wood aggregate can play a role in purifying a water body.

The conception, specific structure and technical effects of the present invention will be further described in conjunction with the accompanying drawings to fully understand the purpose, characteristics and effects of the present invention.

Drawings

FIG. 1 is a photograph of a concrete surface crushed after 3 months of immersion in a water bath of the cement wood concrete of examples 5 and 7 of the present invention;

FIG. 2 is a graph showing the compressive strength of a concrete block made of the cement wood concrete of example 7.

Detailed Description

The technical contents of the preferred embodiments of the present invention will be more clearly and easily understood by referring to the drawings attached to the specification. The present invention may be embodied in many different forms of embodiments and the scope of the invention is not limited to the embodiments set forth herein.

In the invention, the range of (A-B) to (C-D) includes the endpoints of A, B, C and D. For example, for the range of (10-100) to (1-5), the ratio of 10.

The invention provides a cement wood concrete, which comprises cement, water, wood aggregate and an additive; the surface of the wood aggregate is provided with a layer of anticorrosion hydrophobic film. The anti-corrosion hydrophobic film can isolate the wood aggregate from water and resist the invasion of water and bacteria to the wood aggregate, so that the wood aggregate is not easy to rot and expand. The anticorrosive hydrophobic film is formed by soaking wood aggregate in anticorrosive hydrophobic agent containing wood vinegar. The wood aggregate comprises wood coarse aggregate, wood fine aggregate, wood fiber or any mixture thereof. The wood aggregate is obtained by cutting or crushing plants or plant wastes, the wood coarse aggregate comprises wood strips, wood chips, bamboo strips, bamboo chips or any mixture thereof, and the size (the longest side, namely the length) of the wood coarse aggregate is preferably less than 10cm, and more preferably 1cm to 5cm; the fine wood aggregate comprises wood chips, ground rice flour or a mixture thereof; the wood fiber includes linear wood fiber, and the length of the linear wood fiber is preferably 3-6cm.

In one embodiment, the antiseptic water repellent further comprises chitosan and/or sodium alginate.

In one embodiment, the anti-corrosion water repellent consists of wood vinegar and chitosan, wherein the weight ratio of wood vinegar to chitosan is (10-100) to (1-5).

In one embodiment, the anticorrosion water repellent consists of wood vinegar, chitosan and sodium alginate, wherein the weight ratio of the wood vinegar to the chitosan to the sodium alginate is (10-100) to (1-5) to (0.5-1), and is preferably 100.

In one embodiment, the soaking time is 1-15 days, preferably 1-3 days, more preferably 3 days.

In one embodiment, the moisture content of the wood aggregate is 12% -15%.

In one embodiment, the weight ratio of the cement, the water, the wood aggregate and the admixture is 100 (35-45): (40-65): 1-2). The cement is ordinary portland cement, slag portland cement, pozzolana portland cement, fly ash portland cement or composite portland cement, and the number of the cement is 32.5, 32.5R, 42.5R,52.5 or 52.5R.

In one embodiment, the wood aggregate comprises wood coarse aggregate and wood fine aggregate, and the weight ratio of the wood coarse aggregate to the wood fine aggregate is (2-4): 1.

In one embodiment, the admixture comprises one or more of: concrete water reducing agent, concrete retarder, concrete accelerator, concrete emulsion agent and spice powder.

In one embodiment, the cementitious wood concrete further comprises fly ash or silica fume.

In an embodiment, the cement wood concrete further comprises sand and/or crushed stone.

In one embodiment, the cement wood concrete comprises cement, water, wood aggregate, fly ash and a concrete emulsion agent, wherein the weight ratio of the cement to the water to the wood aggregate to the fly ash to the concrete emulsion agent is 100 (40-45) to (40-55) to (10-15) to (1-2), the wood aggregate is a mixture of wood coarse aggregate and wood fine aggregate, and the weight ratio of the wood coarse aggregate to the wood fine aggregate is 2-4 to 1.

In one embodiment, the cement wood concrete comprises cement, water, wood aggregate, fly ash and concrete emulsion agent, wherein the weight ratio of the cement, the water, the wood aggregate, the fly ash and the concrete emulsion agent is 100 (35-40): (50-65): (10-15): (1-2), and the wood aggregate is wood coarse aggregate.

The present invention will be described in further detail with reference to specific examples.

The materials used in the present invention can be obtained by direct purchase unless otherwise specified. The experimental methods used in the present invention are conventional in the art unless otherwise specified.

The cement of the invention adopts 32.5 ordinary Portland cement.

Example 1

The invention provides a wood aggregate soaked by an anti-corrosion water repellent, which is prepared by the following steps:

step 1, preparing wood strips (wood coarse aggregate) with the particle length of 1-5cm, crushed rice hulls (wood fine aggregate) and linear wood fibers with the length of 3-6 cm;

step 2, respectively pouring the pyroligneous into 3 water pools, and then respectively adding water to dilute by 10 times;

and 3, respectively pouring the wood coarse aggregate, the wood fine aggregate and the wood fiber obtained in the step 1 into different water pools filled with diluted wood vinegar, soaking for 1 day, taking out and drying, wherein the moisture content of the dried wood aggregate is 12-15%.

Example 2

step 1, preparing wood strips (wood coarse aggregate) with the particle length of 3-5cm, crushed rice hulls (wood fine aggregate) and linear wood fibers with the length of 3-6 cm;

step 2, pouring the anticorrosive water repellent into 3 water pools respectively, and then adding water to dilute by 20 times; the anti-corrosion water repellent consists of 100 parts by weight of pyroligneous liquor, 1 part by weight of chitosan and 1 part by weight of sodium alginate;

and 3, respectively pouring the wood coarse aggregate, the wood fine aggregate and the wood fiber in the step 1 into different water tanks filled with diluted anticorrosive water repellent, soaking for 3 days, taking out and drying, wherein the moisture content of the dried wood aggregate is 12-15%.

Example 3

step 2, pouring the anticorrosive water repellent into 3 water pools respectively, and then adding water to dilute by 20 times; the antiseptic and water repellent consists of 100 weight parts of pyroligneous liquor, 2.5 weight parts of chitosan and 0.7 weight part of sodium alginate;

and 3, respectively pouring the wood coarse aggregate, the wood fine aggregate and the wood fiber obtained in the step 1 into different water tanks filled with diluted anti-corrosion water repellent, soaking for 3 days, taking out and drying, wherein the moisture content of the dried wood aggregate is 12-15%.

Example 4

step 2, pouring the anticorrosive water repellent into 3 water pools respectively, and then adding water to dilute by 20 times; the antiseptic water repellent consists of 100 parts by weight of wood vinegar, 5 parts by weight of chitosan and 0.5 part by weight of sodium alginate;

Example 5

The invention provides cement wood concrete, which is prepared by the following steps:

step 1, weighing 45 parts by weight of the wood coarse aggregate soaked by the anti-corrosion water repellent in the embodiment 1, and wetting the surface of the wood coarse aggregate;

and 2, pouring the wetted wood coarse aggregate and 100 parts by weight of cement into a concrete mixer, adding 42 parts by weight of water after stirring for a certain time, stirring, continuously adding 2 parts of concrete emulsion agent in the stirring process, and uniformly stirring to obtain the cement wood concrete.

Example 6

The invention provides a cement wood concrete, which is prepared by the following steps:

step 1, weighing 30 parts by weight of wood coarse aggregate soaked by the anti-corrosion water repellent in embodiment 3 and 15 parts by weight of wood fine aggregate soaked by the anti-corrosion water repellent in embodiment 3, and wetting the surfaces of the wood coarse aggregate and the wood fine aggregate;

and 2, pouring the wetted wood coarse aggregate and wood fine aggregate and 100 parts by weight of cement into a concrete mixer, adding 40 parts by weight of water after stirring for a certain time, continuously adding 5 parts by weight of fly ash and 2 parts by weight of concrete emulsion agent in the stirring process, and uniformly stirring to obtain the cement-wood concrete.

Example 7

step 1, weighing 40 parts by weight of wood coarse aggregate soaked by the anti-corrosion water repellent in embodiment 3 and 10 parts by weight of wood fine aggregate soaked by the anti-corrosion water repellent in embodiment 3, and wetting the surfaces of the wood coarse aggregate and the wood fine aggregate;

and 2, pouring the wetted wood coarse aggregate and wood fine aggregate and 100 parts by weight of cement into a concrete mixer, adding 40 parts by weight of water after stirring for a certain time, continuously adding 10 parts by weight of fly ash and 2 parts by weight of concrete emulsion agent in the stirring process, and uniformly stirring to obtain the cement-wood concrete.

Example 8

The invention provides permeable cement wood concrete, which is prepared by the following steps:

step 1, weighing 65 parts by weight of the wood coarse aggregate soaked by the anti-corrosion water repellent in the embodiment 3, and wetting the surface of the wood coarse aggregate;

and 2, pouring the wetted wood coarse aggregate and 100 parts by weight of cement into a concrete mixer, adding 40 parts by weight of water after stirring for a certain time, stirring, continuously adding 10 parts by weight of fly ash and 1 part by weight of concrete emulsion agent in the stirring process, and uniformly stirring to obtain the pervious cement wood concrete.

Comparative example 1

Step 1, weighing 45 parts by weight of wood coarse aggregate which is not soaked by the anti-corrosion water repellent, and wetting the surface of the wood coarse aggregate;

and 2, pouring the wetted wood coarse aggregate and 100 parts by weight of cement into a concrete mixer, adding 42 parts by weight of water after stirring for a certain time, stirring, continuously adding 2 parts of concrete emulsion agent in the stirring process, and uniformly stirring to obtain the cement-wood concrete.

Comparative example 2

Weighing 250 parts by weight of sand, 200 parts by weight of broken stone and 100 parts by weight of cement, pouring the mixture into a concrete mixer, stirring for a certain time, adding 50 parts by weight of water, stirring, continuously adding 10 parts by weight of fly ash and 2 parts by weight of concrete emulsion agent in the stirring process, and uniformly stirring to obtain the common concrete.

And (3) testing the corrosion resistance and the expansion resistance of the cement wood concrete:

and (3) testing the corrosion resistance: concrete blocks with the length, width and height of 20cm are cast by using the cement wood concrete in the embodiment 5 and the embodiment 7 respectively, then the concrete blocks are placed in a water tank, and after the concrete blocks are soaked for 3 months, the rotting condition of the wood aggregate is observed by knocking the concrete blocks.

Fig. 1 is a photograph of a crushed concrete surface (wood aggregate is circled) after soaking in a water bath for 3 months, the left is a photograph of the surface of the concrete fragment in example 7, and the right is a photograph of the surface of the concrete fragment in example 5. It can be seen that almost no decay of the wood aggregate was observed in the concrete of examples 5 and 7.

And (3) testing the swelling resistance: two identical barrels were prepared, the cement wood concrete of example 5 and the cement wood concrete of comparative example 1 were poured into the two barrels, respectively, to ensure that no air bubbles were generated in the concrete during the pouring, and then the surfaces of the concrete in the barrels were all smoothed, and the swelling of the concrete was observed after it was dried.

It was found that the concrete of comparative example 1 was significantly expanded after drying, and the surface area of the concrete (i.e., the surface area of the barrel) before drying was 706.5cm ² The surface area of the concrete after drying is 907.5cm ² The expanded surface area accounted for 28.4%. While the concrete of example 5 hardly expanded after drying, and its surface area was 708.6cm after drying ² Surface area before drying with concrete (706.5 cm) ² ) There is little difference.

Therefore, the cement wood concrete prepared by using the wood aggregate soaked by the anticorrosion and anti-swelling agent of the invention has excellent anticorrosion and anti-swelling properties.

Testing the compressive strength of the cement-wood concrete:

the concrete bricks (test specimen size: 150mm. About.150mm, shape: cube, test specimen age: 28 days) prepared from the concrete of example 7 were subjected to a compressive strength test by a general concrete mechanical properties test experimental method (GB/T50081-2002). The compressive strength curve is shown in FIG. 2, and the measured compressive strength is 22.75MPa.

And (3) testing the flexural strength of the cement wood concrete:

the concrete block (sample size: 150mm 550mm, shape: prism, sample age: 28 days) prepared from the concrete of example 7 was subjected to a flexural strength test by a general concrete mechanical property test experimental method (GB/T50081-2002), and the flexural strength was 570MPa.

Testing the water permeability of the pervious cement wood concrete:

the calculation formula of the concrete permeability coefficient is as follows: k is a radical of _T ＝QL/AHt，

In the formula: k is a radical of formula _T The water permeability coefficient (mm/s) of the sample at the water temperature of T ℃;

q is the amount of water (mm) that oozes out in t seconds ³ )；

L is the thickness (mm) of the sample;

a is the upper surface area (mm) of the sample ² )；

H is the water head difference (mm);

t is time(s).

A cubic concrete block specimen having a side length of 150mm, i.e., a specimen thickness L of 150mm, was prepared using the pervious cement wood concrete of example 8.

A water receiving container is arranged below the concrete sample, a cylindrical container with two open ends is arranged above the sample, the radius of the cylindrical container is 47mm, namely the upper surface area A of the sample with water seepage is 6936.26mm ² Water was poured into the cylindrical container so that the water level difference H was 150mm. After t =149s, the amount of exudation Q was 2X 10 ⁵ mm ³ 。

Finally calculating to obtain a water permeability coefficient k _T 1.4513mm/s, and has excellent water permeability.

Testing the heat preservation performance of the cement wood concrete:

a concrete sample was prepared with the cement wood concrete of example 7 at specification 100mm 30mm and a concrete sample was prepared with the ordinary concrete of comparative example 2 at specification 100mm 30mm. The thermal conductivity of the two concrete samples was measured by the transient flat plate heat source method, and the thermal conductivity of the cement-wood concrete sample of example 7 at 25 ℃ was 0.48396W/(m.K), and the thermal conductivity of the ordinary concrete sample of comparative example 2 at 25 ℃ was 1.45295W/(m.K).

Therefore, the heat insulation performance of the cement wood concrete is obviously superior to that of common concrete.

The experimental data show that the cement wood concrete has excellent corrosion resistance and expansion resistance, and the compression resistance and the fracture resistance of the cement wood concrete can reach the same strength as that of common concrete. The cement wood concrete also has excellent water permeability and heat preservation.

The foregoing detailed description of the preferred embodiments of the invention has been presented. It should be understood that numerous modifications and variations could be devised by those skilled in the art in light of the present teachings without departing from the inventive concepts. Therefore, the technical solutions available to those skilled in the art through logic analysis, reasoning and limited experiments based on the prior art according to the concept of the present invention should be within the scope of protection defined by the claims.

Claims

1. The cement wood concrete is characterized by comprising cement, water, wood aggregate and an additive; the surface of the wood aggregate is provided with a layer of anticorrosive hydrophobic film.

2. The cement wood concrete of claim 1, wherein the anti-corrosion hydrophobic film is formed by soaking the wood aggregate in an anti-corrosion hydrophobic agent comprising wood vinegar.

3. The cement wood concrete of claim 2, wherein the anti-corrosive water repellent further comprises chitosan and/or sodium alginate.

4. The cement wood concrete according to claim 1, wherein the wood aggregate comprises one or more of the following materials: wood coarse aggregate, wood fine aggregate and wood fiber; wherein, the first and the second end of the pipe are connected with each other,

the wood coarse aggregate comprises one or more of the following materials: wood strands, wood chips, bamboo strands, bamboo chips;

the wood fine aggregate comprises one or more of the following materials: crushed materials of wood chips and rice husk;

the wood fibers include linear wood fibers.

5. The cement wood concrete according to claim 1, wherein the weight ratio of the cement, water, wood aggregate and admixture is 100 (35-45): 40-65: 1-2.

6. The cement wood concrete according to claim 1, wherein the wood aggregate comprises wood coarse aggregate and wood fine aggregate, and the weight ratio of the wood coarse aggregate to the wood fine aggregate is (2-4): 1.

7. The cement wood concrete according to claim 1, wherein the admixture comprises one or more of: concrete water reducing agent, concrete retarder, concrete accelerator and concrete emulsion agent.

8. The cement wood concrete according to claim 1, further comprising fly ash or silica fume.

9. The cement wood concrete according to claim 1, further comprising sand and/or crushed stone.

10. The cement wood concrete according to claim 1, wherein the cement wood concrete comprises cement, water, wood aggregate, fly ash and concrete emulsion agent, wherein the weight ratio of the cement, the water, the wood aggregate, the fly ash and the concrete emulsion agent is 100 (40-45): 40-55): 5-10): 1-2, the wood aggregate is a mixture of wood coarse aggregate and wood fine aggregate, and the weight ratio of the wood coarse aggregate and the wood fine aggregate is 2-4): 1.

11. The cement wood concrete according to claim 1, wherein the cement wood concrete comprises cement, water, wood aggregate, fly ash and concrete emulsion agent, wherein the weight ratio of the cement, the water, the wood aggregate, the fly ash and the concrete emulsion agent is 100 (35-40) to (50-65) to (5-10) to (1-2), and the wood aggregate is wood coarse aggregate.

12. The anti-corrosion water repellent is characterized by comprising wood vinegar.

13. The anti-corrosive hydrophobic agent of claim 12, wherein the anti-corrosive hydrophobic agent further comprises chitosan and/or sodium alginate.

14. The anti-corrosive water repellent of claim 13, wherein the anti-corrosive water repellent comprises wood vinegar and chitosan, wherein the weight ratio of wood vinegar to chitosan is (10-100) to (1-5).

15. The antiseptic water repellent of claim 13, wherein the antiseptic water repellent consists of wood vinegar, chitosan and sodium alginate, wherein the weight ratio of wood vinegar, chitosan and sodium alginate is (10-100): 1-5: 0.5-1).

16. A wood aggregate impregnated with the preservative water repellent of any one of claims 12 to 15.

17. The preparation method of the cement wood concrete is characterized by comprising the following steps:

step 1, wetting the surface of the wood aggregate of claim 16;

18. The cement wood concrete of claim 17, further comprising fly ash added in step 2.

19. The cement wood concrete according to claim 17, wherein a waste liquid of the anti-corrosive water repellent is further added in step 2.

20. Use of the cement wood concrete according to any one of claims 1 to 11 for the manufacture of roads, concrete bricks, concrete walls, flower pots, flower stands, flower boxes, railings, curbstones and stools.