Performance-improved modified raw soil material

Abstract

The invention belongs to the technical field of building materials, and particularly relates to a traditional mortar modified immature soil material for improving comprehensive performance, which is prepared from the following raw materials in parts by mass: 80 to 90 parts of immature soil, 6.5 to 8 parts of glutinous rice mortar, 6 to 10 parts of egg white mortar and 0.8 to 1 part of brown sugar mortar. Compared with the prior art, the compressive strength, the water resistance and the thermal performance of the modified immature soil material are greatly improved, and the prepared immature soil material can be effectively applied to the fields of immature soil building reinforcement, cultural relic and ancient building repair and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of building materials, and particularly relates to a traditional mortar modified raw earth material for improving comprehensive performance. Background Art

[0002] As a recyclable, energy-saving and environment-friendly material, raw earth material can effectively reduce the dependence on limited natural resources, reduce energy consumption during the building process, and reduce carbon emissions, thus generating more positive environmental benefits. However, due to its discrete and brittle characteristics, raw earth material has poor physical and mechanical properties, which in turn affects the durability and seismic performance of raw earth buildings.

[0003] There are many existing cultural relics protection buildings with raw earth structures in various parts of China. These buildings have distinct regional styles and ethnic characteristics and have stood for hundreds of years. At present, a large number of cultural relics protection buildings with raw earth structures are severely damaged and need protective restoration. However, many traditional raw earth mortar modification formulas have been lost. Determining the traditional mortar modification mix ratio scheme for raw earth materials is of great significance for inheriting raw earth building culture and protecting ancient cultural buildings.

[0004] In ancient China, there were records of using lime, yellow mud, and sand and gravel as main materials, adding precise proportions of brown sugar, egg white, glutinous rice slurry, etc., mixing them evenly, and then using special preparation processes to use them as building materials. However, these records are often accompanied by relatively complex preparation processes, and the precise components of various raw materials have not been made public. Summary of the Invention

[0005] The invention aims to provide a modified raw earth material to improve the compressive strength, water resistance and thermal performance of the raw earth material, so as to enhance the seismic performance and environmental performance of the raw earth building wall structure.

[0006] To achieve the above object, the present invention adopts the following technical solutions: A performance-improved modified raw earth material is composed of the following raw materials in parts by mass: 80-90 parts of raw earth, 6.5-8 parts of glutinous rice mortar, 6-10 parts of egg white mortar, and 0.8-1 part of brown sugar mortar.

[0007] It is composed of the following raw materials in parts by mass: 85 parts of raw earth, 7.6 parts of glutinous rice mortar, 8.2 parts of egg white mortar, and 0.9 part of brown sugar mortar.

[0008] It also includes the following raw materials in parts by mass: 0.5 part of rubber particles and 2 parts of quick-dissolving colloid powder.

[0009] It also includes the following raw materials in parts by mass: 2 parts of basalt short fibers or polypropylene cellulose.

[0010] The particle size of the raw earth does not exceed 0.5 mm.

[0011] The preparation process of the glutinous rice mortar is as follows: Mix glutinous rice flour and water evenly according to a mass ratio of 1:9, heat to boiling, keep warm for two hours, add water to the initial liquid level after mixing glutinous rice flour and water during the heating process, and obtain glutinous rice mortar after cooling; Mix the glutinous rice mortar and lime water according to a volume ratio of 1:1 to obtain glutinous rice mortar.

[0012] The preparation process of the egg white mortar is as follows: Use fresh eggs, break them and pour them into a container, separate the egg white liquid, and mix the egg white liquid and lime water according to a volume ratio of 1:1 to obtain egg white mortar.

[0013] The preparation process of the brown sugar mortar is as follows: Mix saturated brown sugar water at room temperature and lime water according to a volume ratio of 1:1.

[0014] The lime water is a 0.02 mol / L calcium hydroxide suspension.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. The compressive strength, water resistance, and thermal performance of the obtained modified rammed earth materials have been greatly improved, and the prepared rammed earth materials can be effectively applied to fields such as rammed earth building reinforcement and the restoration of ancient cultural relics buildings.

[0016] 2. The mortar raw materials used in the present invention are widely available, low-cost, environmentally friendly, and the preparation process is simple and easy to operate. Description of the Drawings

[0017] Figure 1 It is a contour map and a response surface map of the 28-day compressive strength of the specimen made of the modified rammed earth material of the present invention.

[0018] Figure 2 It is a contour map and a response surface map of the influence of the interaction between the dosages of the modified materials on the water absorption rate.

[0019] Figure 3 It is a contour map and a response surface map of the influence of the interaction between the dosages of the modified materials on the thermal conductivity.

[0020] Figure 1 It shows that the dosage of brown sugar mortar has the most significant influence on the 28-day compressive strength of the modified rammed earth specimen, followed by the dosage of glutinous rice mortar, and the dosage of egg white mortar has the least influence.

[0021] Figure 2 It shows that the interaction between the dosages of glutinous rice mortar and egg white mortar is significant, and the interaction between the dosages of egg white mortar and brown sugar mortar is significant.

[0022] Figure 3It is shown that when the dosages of glutinous rice mortar and egg white mortar are about 8%, the response surface diagram shows extreme points, indicating that the thermal conductivity of the modified rammed earth specimens is the smallest at this time. Specific implementation mode

[0023] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0024] A performance-improved modified rammed earth material is composed of the following raw materials in parts by mass: 80-90 parts, 6.5-8 parts of glutinous rice mortar, 6-10 parts of egg white mortar, and 0.8-1 part of brown sugar mortar.

[0025] Preferably, the above-mentioned modified rammed earth material is composed of the following raw materials in parts by mass: 85 parts of rammed earth, 7.6 parts of glutinous rice mortar, 8.2 parts of egg white mortar, and 0.9 part of brown sugar mortar.

[0026] It also includes 0.5 part of rubber particles and 2 parts of quick-dissolving glue powder. The rubber is crushed, and rubber particles with a particle size of 1 mm to 2 mm are selected. 2 parts of quick-dissolving glue powder are dissolved in 15 parts of water to obtain a quick-dissolving glue powder solution.

[0027] It also includes 2 parts of basalt short fibers or polypropylene fibers.

[0028] The particle size of the rammed earth does not exceed 0.5 mm.

[0029] The preparation process of the glutinous rice mortar is as follows: Mix glutinous rice flour and water in a mass ratio of 1:9 evenly, heat to boiling and keep warm for two hours. During the heating process, add water to the initial liquid level after mixing glutinous rice flour and water, and obtain glutinous rice slurry after cooling; Mix the glutinous rice slurry and lime water in a volume ratio of 1:1 to obtain glutinous rice mortar. The glutinous rice flour used in each embodiment of the present invention is Huangguopai glutinous rice flour purchased from the market.

[0030] The preparation process of the egg white mortar is as follows: Use fresh eggs, break them and pour them into a container, separate the egg white liquid, and mix the egg white liquid and lime water in a volume ratio of 1:1 to obtain egg white mortar.

[0031] The preparation process of the brown sugar mortar is to mix saturated brown sugar water at room temperature and lime water in a volume ratio of 1:1.

[0032] The preparation process of lime water is as follows: Add calcium hydroxide powder to clear water at 20°C ± 2°C in proportion, stir well and let it stand, and obtain a 0.02 mol / L calcium hydroxide suspension.

[0033] Mechanism of action of various components of the raw materials of a performance-improved modified raw soil material of the present invention: Raw soil: Also known as dead soil, it refers to natural soil that has not been disturbed by humans, that is, soil that has not been turned over, usually existing more than one meter below the ground surface where sunlight is not seen all year round and there is no plant growth on the soil surface. In the natural soil in the wild, the loose surface layer with a large number of plant roots on the surface is mature soil, and the compact soil below that is difficult for plant roots to reach is raw soil. The raw soil in the embodiments of the present invention is selected from red clay in Jiangxi region.

[0034] Glutinous rice mortar: By mixing glutinous rice slurry and lime water, a gelling agent with high adhesion is formed, which can play a cementing role between clay particles. The main components of glutinous rice are carbohydrates, proteins and fats, and most of the carbohydrates are branched-chain starches, which have high viscosity after being cooked.

[0035] Egg white mortar: There is a strong adhesion between the egg white mortar and the soil particles, and it has high impermeability and freeze-thaw resistance. The egg white in the mortar will undergo a series of chemical reactions to play the roles of aeration, adhesion, sterilization and waterproofing. The reason is related to the interfacial activity of protein molecules and hydration products and the regulatory role of biomineralization.

[0036] Brown sugar mortar: Brown sugar refers to the finished sugar of sugarcane with honey. The main component of brown sugar is sucrose, and sucrose and calcium hydroxide can react to form sucrose calcium with greater solubility. Therefore, after mixing with lime water, sucrose plays the role of a water-reducing agent, reducing the water consumption of the brown sugar mortar, and thus the brown sugar mortar has better volume shrinkage.

[0037] For the raw soil specimens prepared by the present invention, after 28 days of curing, the performance indicators such as compressive strength, water absorption rate, and thermal conductivity are all significantly improved compared with the comparative examples, and the integrity of the specimens is better after being damaged. It can not only improve the compressive strength of the raw soil material, but also improve the water resistance and thermal performance of the raw soil material, changing the disadvantage that traditional raw soil materials are prone to brittle failure.

[0038] Example 1 This example provides a performance-improved modified raw soil material, in which the raw material ratio is calculated by mass, 6.5 parts of glutinous rice mortar, 8 parts of egg white mortar, 2 parts of brown sugar mortar, and 80 parts of raw soil.

[0039] Example 2 This example provides a performance-improved modified raw soil material, in which the raw material ratio is calculated by mass, 7 parts of glutinous rice mortar, 6 parts of egg white mortar, 1.25 parts of brown sugar mortar, and 86 parts of raw soil.

[0040] Example 3 This embodiment provides a performance-improved modified raw soil material. The raw material ratio is as follows by mass: 7.6 parts of glutinous rice mortar, 8.2 parts of egg white mortar, 0.9 parts of brown sugar mortar, and 83 parts of raw soil.

[0041] Example 4 This embodiment provides a performance-improved modified raw soil material. The raw material ratio is as follows by mass: 8 parts of glutinous rice mortar, 8 parts of egg white mortar, 1.5 parts of brown sugar mortar, and 85 parts of raw soil.

[0042] Example 5 This embodiment provides a performance-improved modified raw soil material. The raw material ratio is as follows by mass: 7.8 parts of glutinous rice mortar, 8.5 parts of egg white mortar, 1 part of brown sugar mortar, and 85 parts of raw soil.

[0043] Example 6 This embodiment provides a performance-improved modified raw soil material. The raw material ratio is as follows by mass: 7.6 parts of glutinous rice mortar, 8.2 parts of egg white mortar, 0.9 parts of brown sugar mortar, 0.5 part of rubber particles, 2 parts of quick-dissolving colloid powder, and 83 parts of raw soil. This embodiment is an optimization based on Example 3, adding rubber particles and quick-dissolving colloid powder. The rubber particles are obtained by crushing rubber, and rubber particles with a particle size of 1 mm to 2 mm are selected. The quick-dissolving colloid powder is obtained by dissolving 2 parts of quick-dissolving colloid powder in 15 parts of water to obtain a quick-dissolving colloid powder solution, which is added in the form of a solution.

[0044] Rubber is a high-molecular compound mainly composed of polyisoprene. Based on the good elasticity of rubber, when the raw soil material deforms, it consumes the deformation energy, strengthening the material's ability to resist deformation. Quick-dissolving colloid powder: The protective colloid of the quick-dissolving colloid powder has strong hydrophilic properties. The structure itself has vinyl groups with internal plasticizing effects. Coupled with its dispersion and penetration effects, the polymer film formed after dissolving in water can effectively wrap loose soil particles, thereby making their internal connections tight and further filling the pores generated by uneven stirring.

[0045] Example 7 This embodiment provides a performance-improved modified raw soil material. The raw material ratio is as follows by mass: 7.6 parts of glutinous rice mortar, 8.2 parts of egg white mortar, 0.9 parts of brown sugar mortar, 0.5 part of rubber particles, 2 parts of quick-dissolving colloid powder, 2 parts of basalt short fibers, and 83 parts of raw soil. This embodiment is a further optimization based on Example 6. Basalt short fibers have high temperature resistance, oxidation resistance, radiation resistance, heat insulation and sound insulation, good filtering properties, high compressive strength and shear strength, and are suitable for use in various environments, which can make up for the technical problems of poor adhesion and poor anti-seepage performance of the raw soil material.

[0046] Comparative Example 1 It is plain soil, that is, all components are raw soil, and Jiangxi red soil is selected.

[0047] Comparative Example 2 81 parts of raw soil, 10 parts of glutinous rice mortar, 0.5 part of brown sugar mortar, and 8 parts of egg white mortar.

[0048] Performance test: Three specimens were made for each of the above examples and comparative examples, and the test results were the average values obtained from the three specimens of each example and comparative example.

[0049] Compressive strength test: Referring to the "Standard for Geotechnical Test Methods" GB / T50123-2019, the unconfined compressive strength of the raw soil specimens at 28 days was tested. The test machine was a universal testing machine, and the loading method was displacement-controlled loading with a loading speed set at 0.1 mm / s.

[0050] Water resistance test: The soil sample was sieved through a 2 mm sieve, and specimens with dimensions of 50 mm×50 mm×50 mm were molded according to the ratio and cured naturally for 28 days, followed by an immersion test, with the water absorption rate used as the characterization.

[0051] Thermal performance test: The test of thermal performance indicators was carried out using a Hot disk TPS-1500S thermal conductivity meter. During the test, the probe was placed between two raw soil specimens. By applying a current sufficient to cause the temperature rise of the probe to be less than one degree to several degrees, and simultaneously recording the relationship between the increase in resistance (temperature) and time, the thermal conductivity could be directly obtained from the mathematical model.

[0052] The test results of the above various performance tests are listed in Table 1 below.

[0053] Table 1 Comprehensive performance test results of specimens Specimen group Average compressive strength (MPa) Average water absorption rate (%) Thermal conductivity Example 1 13.5 5.4 0.513 Example 2 13.34 5.1 0.731 Example 3 15.02 2.25 0.634 Example 4 15.58 2.2 0.668 Example 5 15.17 3.6 0.641 Example 6 16.05 2.24 0.621 Example 7 16.02 2.11 0.633 Comparative example 1 5.37 / 1.012 Comparative example 2 7.17 6.6 0.778 The comprehensive performance test results of the specimens of the present invention, and the comparison results between Examples 1-7 and Comparative Examples 1 and 2 are shown in Table 1. Compared with Comparative Example 1, the compressive strength of Examples 1-5 has been greatly improved. The addition of rubber particles in Example 6 improves the ability of the raw soil material to resist deformation, enhances the mechanical properties, and the quick-dissolving colloid powder can fill the pores generated by uneven material mixing, strengthening the connection between internal components and making the construction more convenient.

[0054] In Example 7, the addition of basalt cellulose further improves the bonding property and impermeability of the raw soil material.

[0055] At the same time, the water resistance and thermal performance of Examples 3-7 have also been improved to a certain extent compared with the comparative examples. When the dosage of glutinous rice mortar and egg white mortar is about 8% of the total mass parts, it shows that the thermal conductivity of the modified raw soil specimens is the smallest and the comprehensive performance is the best at this time.

[0056] It should be understood that the above description of the preferred embodiments is relatively detailed, and it should not be considered as a limitation to the protection scope of the present invention patent. Under the inspiration of the present invention, those of ordinary skill in the art can also make substitutions or deformations without departing from the scope protected by the claims of the present invention, and all fall within the protection scope of the present invention. The scope of protection claimed by the present invention shall be subject to the appended claims.

Claims

1. A modified soil material with improved performance, characterized in that , composed of the following raw materials in parts by mass: 80-90 parts of raw soil, 6.5-8 parts of glutinous rice mortar, 6-10 parts of egg white mortar and 0.8-1 part of brown sugar mortar.

2. The performance-improved modified soil material according to claim 1, characterized in that: The method is composed of the following raw materials in parts by mass: 85 parts of raw soil, 7.6 parts of glutinous rice mortar, 8.2 parts of egg white mortar and 0.9 parts of brown sugar mortar.

3. A performance-improved soil material according to claim 1 or 2, characterized in that: The invention also includes the following raw materials in parts by weight: 0.5 parts of rubber particles and 2 parts of instant rubber powder.

4. The performance-improved soil material according to claim 3, characterized in that: The invention also includes the following raw materials in parts by weight: 2 parts of basalt staple fibers or polypropylene cellulose.

5. A modified soil material with improved performance according to claim 1, characterized in that: The particle size of the raw soil does not exceed 0.5 mm.

6. A modified soil material with improved performance according to claim 1, characterized in that: The preparation process of the glutinous rice mortar is as follows: glutinous rice flour and water are uniformly mixed in a mass ratio of 1:9, heated to boiling and then kept warm for two hours, water is added during the heating process to the initial liquid level after the glutinous rice flour and water are uniformly mixed, and glutinous rice paste is obtained after cooling; glutinous rice paste and lime water are mixed in a volume ratio of 1:1 to obtain glutinous rice mortar.

7. A modified soil material with improved performance according to claim 1, characterized in that: The preparation process of the egg white mortar comprises the following steps: breaking fresh eggs and pouring them into a container, separating the egg white liquid, and mixing the egg white liquid with lime water in a volume ratio of 1:1 to obtain the egg white mortar.

8. The performance-improved modified soil material according to claim 1, characterized in that: The preparation process of the brown sugar mortar is to mix saturated brown sugar water and lime water at room temperature in a volume ratio of 1:

1.

9. A modified soil material with improved performance according to any one of claims 4 to 6, characterized in that: The lime water is a 0.02 mol / L calcium hydroxide suspension.

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