CN116768583A - High-performance paving cushion material and preparation method thereof - Google Patents

Abstract

The invention relates to a high-performance paving cushion material and a preparation method thereof. According to the formula, cement base material, active mixed material, coarse aggregate, quartz sand, alkali activator and water are stirred evenly to obtain a high-performance paving cushion material. ; Wherein, the cement base material includes at least one of sulphoaluminate cement, Portland cement or anhydrite. Compared with the existing technology, the present invention uses a ternary system of sulphoaluminate cement-Portland cement-gypsum to replace part of Portland cement, which improves the problem that the early-stage strength of the pavement cushion is low and easy to loosen. Moreover, the present invention uses more solid waste materials, effectively achieving green energy saving and efficient resource recycling.

Description

High-performance paving cushion material and preparation method thereof

Technical field

The invention relates to the technical field of civil engineering material preparation, and in particular to a high-performance paving cushion material and a preparation method thereof.

Background technique

With the rapid development of the market economy, the highway industry, one of the infrastructures, has also developed rapidly. Among them, the pavement cushion, as an important part of the pavement structure, has the functions of load-bearing, waterproofing and anti-freeze. Its quality will directly affect the load-bearing capacity and durability of the subgrade and pavement, and then affect the stability and safety of the pavement structure project. .

Under normal circumstances, the selection of cushion materials is roughly the same as that of pavement materials, both of which need to have a high elastic modulus to resist deformation caused by external forces and release internal stress. During cushion construction, coarse aggregates such as ores will be used as engineering raw materials. This is due to the ore's high strength, good wear resistance and good waterproof properties, making it the best choice for pavement cushion construction materials. In order to control costs, low-grade road projects currently have no requirements for the gradation of ore in the cushion layer; while the construction of high-grade roads has higher requirements for the quality of the cushion layer. Not only should the ore with better quality be selected, but the gradation classification should also be arranged reasonably.

In order to meet the strength requirements of the pavement cushion and ensure that the material has good adhesion and volume stability, in addition to strict requirements on material selection, the mix ratio of various raw materials must also be strictly configured. Currently, the commonly used pavement cushion material is gravel cushion, which is composed of Portland cement, gravel and sand and has good economic applicability. However, this type of sand and gravel cushion has poor bonding performance and volume stability, and there is a hidden danger of subsidence and damage to the road surface in the later stage.

Contents of the invention

The object of the present invention is to provide a high-performance paving cushion material and a preparation method thereof in order to overcome at least one of the above-mentioned defects in the prior art. This paving cushion material uses the ternary system of sulphoaluminate cement-Portland cement-gypsum as the cement base material, supplemented by various solid waste materials and graded sand and gravel to prepare a high-performance pavement cushion material; it is different from ordinary pavement Compared with cushion materials, this paving cushion material has the advantages of higher strength, good bonding performance and small shrinkage, and can be suitable for most road cushions.

The object of the present invention can be achieved through the following technical solutions:

One of the objects of the present invention is a high-performance paving cushion material, including a cement base material and an active mixed material with a mass ratio of (40-70): (80-120), and other components; the cement base material Including at least one of sulphoaluminate cement, Portland cement or anhydrite.

Further, it includes the following components by mass: 40-70 parts of cement base material, 80-120 parts of active mixed material, 240-720 parts of coarse aggregate, 120-360 parts of quartz sand, 3-6 parts of alkali activator and 36 to 76 parts of water.

Further, the cement base material is composed of sulfoaluminate cement, Portland cement and anhydrite.

Furthermore, the mass of the sulfoaluminate cement accounts for 5% to 30% of the total mass of the cement base material. If there is too little sulfoaluminate cement, the reinforcing effect will not be obvious. If there is too much sulfoaluminate cement, not only will the cost increase, but it will also easily cause later problems. Strength shrinkage phenomenon; the mass of anhydrous gypsum accounts for 5% to 25% of the total mass of the cement base material. Adding gypsum can promote the hydration of the cement base material. If the amount of anhydrous gypsum is too small, the hydration promotion effect will be ineffective. Obviously; if the amount of anhydrous gypsum is too much, it will cause excessive expansion and damage of the system.

Further, the active mixed material includes fly ash and/or limestone powder.

Further, the particle size range of fly ash is approximately 600kg·m ^-3 ; the particle size range of limestone powder is approximately 500kg·m ^-3 .

Further, the coarse aggregate includes crushed stone and/or steel slag.

Further, the particle size of the coarse aggregate is between 5 and 40 mm, and the maximum particle size is no more than two-thirds of the thickness of the cushion layer.

Further, the base activator includes sodium hydroxide and/or sodium silicate.

The second object of the present invention is a method for preparing a high-performance paving cushion material as described above, which includes the following steps: according to the formula, combine cement base material, active mixed material, coarse aggregate, quartz sand, alkali activator and water Stir evenly to obtain high-performance paving cushion material.

Compared with the prior art, the present invention has the following advantages:

(1) The present invention uses the ternary system of sulphoaluminate cement-Portland cement-gypsum to replace part of Portland cement, which improves the problem that the pavement cushion has low early strength and is easy to loosen. Moreover, the present invention uses more solid waste materials, effectively achieving green energy saving and efficient resource recycling.

(2) Compared with ordinary Portland cement, the addition of sulfoaluminate cement and anhydrite can effectively inhibit cracks caused by cushion shrinkage and increase volume stability.

Description of drawings

Figure 1 is a graph showing the shrinkage performance of the high-performance paving cushion materials designed in Examples 1-3 and Comparative Example 1.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented on the premise of the technical solution of the present invention, and detailed implementation modes and specific operating procedures are given. However, the protection scope of the present invention is not limited to the following embodiments.

A high-performance paving cushion material, including the following components by mass: 40-70 parts of cement base material, 80-120 parts of active mixed material, 240-720 parts of coarse aggregate, 120-360 parts of quartz sand, alkali excitation 3 to 6 parts of agent and 36 to 76 parts of water.

The cement base material is composed of sulfoaluminate cement, Portland cement and anhydrous gypsum. The mass of the sulfoaluminate cement accounts for 5% to 30% of the total mass of the cement base material. The mass of the anhydrous gypsum accounts for 5% to 25% of the total mass of the cement base material. The active mixed materials include fly ash and limestone powder. The coarse aggregate includes crushed stone and steel slag. The base activator includes sodium hydroxide and/or sodium silicate.

Among them, the sulfoaluminate cement is 42.5 low-alkalinity sulfoaluminate cement produced by Tangshan Polar Bear Building Materials Co., Ltd., and the Portland cement is P·O 42.5 ordinary Portland cement and anhydrous cement produced by Guangdong Yunfu Qingzhou Cement Co., Ltd. Gypsum comes from Anhui Hengtai Non-Metal Materials Company; fly ash particle size range is about 600kg·m ^-3 , from Shandong Shunke Building Materials Technology Co., Ltd.; limestone powder particle size range is about 500kg·m ^-3 , from Shandong Dahe Building Materials Co., Ltd.; gravel comes from Shijiazhuang Chuanxin Mining Co., Ltd.; steel slag comes from Shandong Shanke Solid Waste Resources Co., Ltd., the particle size of the gravel and steel slag is between 5 and 40 mm, and the maximum particle size is no more than one-third of the cushion thickness. two.

Example 1

This embodiment provides a high-performance paving cushion material design and preparation method, which consists of the following components by mass: 5 parts of sulfoaluminate cement, 20 parts of Portland cement, 5 parts of anhydrous gypsum, and pulverized coal 40 parts of ash, 40 parts of limestone powder, 120 parts of gravel, 120 parts of steel slag, 120 parts of quartz sand, 3 parts of sodium hydroxide, and 36 parts of water.

According to the formula, mix the cement base material, active mixed material, coarse aggregate, quartz sand, alkali activator and water evenly to obtain a high-performance paving cushion material. The main performance indicators are shown in Table 1.

Example 2

This embodiment provides a high-performance paving cushion material design and preparation method, which consists of the following components by mass: 10 parts of sulfoaluminate cement, 30 parts of Portland cement, 10 parts of anhydrite, and pulverized coal 60 parts of ash, 20 parts of limestone powder, 120 parts of gravel, 240 parts of steel slag, 120 parts of quartz sand, 3 parts of sodium hydroxide, and 36 parts of water.

According to the formula, mix the cement base material, active mixed material, coarse aggregate, quartz sand, alkali activator and water evenly to obtain a high-performance paving cushion material. The main performance indicators are shown in Table 1.

Example 3

This embodiment provides a high-performance paving cushion material design and preparation method, which consists of the following components by mass: 10 parts by mass of sulfoaluminate cement, 30 parts by Portland cement, 5 parts by anhydrous gypsum, fly ash 60 parts of limestone powder, 120 parts of gravel, 120 parts of steel slag, 160 parts of quartz sand, 3 parts of sodium silicate, and 64 parts of water.

According to the formula, mix the cement base material, active mixed material, coarse aggregate, quartz sand, alkali activator and water evenly to obtain a high-performance paving cushion material. The main performance indicators are shown in Table 1.

Comparative example 1

This comparative example consists of the following components by mass: 40 parts of Portland cement, 40 parts of fly ash, 40 parts of limestone powder, 120 parts of crushed stone, 120 parts of steel slag, 120 parts of quartz sand, 3 parts of sodium hydroxide, 36 parts water.

According to the formula, Portland cement, fly ash, limestone powder, gravel, steel slag, quartz sand, sodium hydroxide and water are mixed evenly to obtain the paving cushion material. The main performance indicators are shown in Table 1.

Table 1 Compressive strength of Examples 1-3 and Comparative Example 1

It can be seen from Table 1 that after 28 days of curing, the compressive strength of the paving cushion material obtained in Comparative Example 1 using only Portland cement as the cement base material is significantly lower than that using the ternary system of sulphoaluminate cement-Portland cement-gypsum. Examples 1-3 of Portland cement, this is because compared with ordinary Portland cement, the ternary system shrinks less, can effectively suppress the generation of cracks in the cushion layer, increase the volume stability, thereby improving the prepared Compressive strength of paving underlayment materials. In addition, the present invention rationally uses alkali activators to promote the hydration of active mixed materials, and the system has better late-stage strength (28d) and has good economic benefits.

The above are only preferred embodiments of the present invention, and are not intended to limit the present invention in other forms. Any skilled person familiar with the art may make changes or modifications to equivalent changes using the technical contents disclosed above. Example. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims (10)

1. A high-performance paving cushion material is characterized by comprising cement base materials and active mixed materials with the mass ratio of (40-70) to (80-120) and other components;

the cement base material comprises at least one of sulphoaluminate cement, silicate cement or anhydrous gypsum.

2. The high-performance paving mat material of claim 1, comprising the following components in parts by mass: 40-70 parts of cement base material, 80-120 parts of active mixed material, 240-720 parts of coarse aggregate, 120-360 parts of quartz sand, 3-6 parts of alkali-activated agent and 36-76 parts of water.

3. A high performance paving mat material as claimed in claim 2 wherein said cement base is comprised of sulfoaluminate cement, portland cement and anhydrite.

4. A high performance paving mat material according to claim 3, wherein the weight of said sulfoaluminate cement is 5% to 30% of the total weight of the cement base; the mass of the anhydrous gypsum accounts for 5-25% of the total mass of the cement base material.

5. A high performance paving mat material as claimed in claim 2, wherein said reactive blend material comprises fly ash and/or limestone powder.

6. A high performance paving mat as defined in claim 5, wherein said fly ash has a particle size in the range of about 600 kg-m ^-3 The method comprises the steps of carrying out a first treatment on the surface of the The limestone powder has the particle size of about 500 kg.m ^-3 。

7. A high performance paving mat as claimed in claim 2, wherein said coarse aggregate comprises crushed stone and/or steel slag.

8. A high performance paving mat material according to claim 7, wherein the coarse aggregate has a particle size of between 5 and 40mm and a maximum particle size of no more than two-thirds of the mat thickness.

9. A high performance paving mat material as claimed in claim 2, wherein said alkali-activator comprises sodium hydroxide and/or sodium silicate.

10. A method of preparing a high performance paving mat as claimed in any of claims 1 to 9, comprising the steps of: according to the formula, the cement base material, the active mixed material, the coarse aggregate, the quartz sand, the alkali-activated agent and the water are uniformly stirred to obtain the high-performance paving cushion material.