AU2021101186A4

AU2021101186A4 - Shrinkage-inhibiting elastic-toughness rubber asphalt material for repairing pavement cracks

Info

Publication number: AU2021101186A4
Application number: AU2021101186A
Authority: AU
Inventors: Hao Li; Jianfei Liu; Chenguang Wan; Shifeng Wang; Xiaofeng Wang; Zhen jun Wang; Bo Yang
Original assignee: Henan Provincial Communication Planning and Design Institute Co Ltd
Current assignee: Henan Provincial Communication Planning and Design Institute Co Ltd
Priority date: 2021-03-05
Filing date: 2021-03-05
Publication date: 2021-05-13
Anticipated expiration: 2029-03-05

Abstract

The invention discloses a self-expanding rubber asphalt material used for crack grouting and filling of an asphalt pavement. The self-expanding rubber asphalt material is prepared from matrix asphalt, waste tire rubber powder, an expansion material, a styrene thermoplastic elastomer and diatomite. The self-expanding rubber asphalt material is prepared by the following steps: heating the matrix asphalt in a premixing tank, then adding the waste tire rubber powder to uniformly stir, throwing the styrene thermoplastic elastomer into the premixing tank, and uniformly mixing under stirring to obtain a mixture; grinding the mixture in a colloid mill for several times, and then continuously stirring for 1-2 hours; and adding the expansion material and the diatomite to continuously stir for 1-2 hours and performing cooling to obtain the target material. According to the self-expanding rubber asphalt material provided by the invention, the waste tire rubber powder, the expansion material, the styrene thermoplastic elastomer and the diatomite are adopted for compound modification of the matrix asphalt, and the prepared self-expanding rubber asphalt material used for crack grouting and filling of the asphalt pavement has extremely good self-expanding properties when being used for early repair of cracks of the pavement, thereby effectively playing a waterproof role; and the self-expanding rubber asphalt material has excellent tensile properties and resilience properties, excellent bonding properties and excellent high and low temperature performance FIGURES OF THE SPECIFICATION 1/1 Evaluation Indexes Example 1 Example 2 Performance Low-temperature tensile passed passed passed test Cone penetration (0.1 45 52 30-70 mm) Softening point (C) 87 81 80 Flowing value (mm) 2.5 3.7 5 Elastic recovery 63 58 30-70 (25°C) % Figure 1.

Description

FIGURES OF THE SPECIFICATION

1/1

Evaluation Indexes Example 1 Example 2 Performance

Low-temperature tensile passed passed passed test Cone penetration (0.1 45 52 30-70 mm)

Softening point (C) 87 81 80

Flowing value (mm) 2.5 3.7 5 Elastic recovery 63 58 30-70 (25°C) %

Figure 1.

Shrinkage-inhibiting elastic-toughness rubber asphalt material for

repairing pavement cracks

TECHNICAL FIELD

The invention relates to an asphalt pavement maintenance technology, in

particular to a self-expanding rubber asphalt material for crack grouting and

filling of an asphalt pavement.

BACKGROUND

As an important construction material for roads, asphalt has been widely

used. Semi-rigid pavement with asphalt concrete as the surface layer will be

affected by temperature gradients and humidity changes during long-term

use, and various cracks will be produced at different levels. The occurrence of

cracks will reduce the safety and comfort of pavement, and the rain will invade

the roadbed along the cracks, causing the structural layer below the base

layer to soften, causing erosion and water stability problems, and reducing the

bearing capacity of the road. At the same time, under the repeated action of a

great deal of traffic load, the pavement surface layers on both sides of the

crack are broken and the pavement is loosened, pitted, smashed and

displaced, so that the performance of the pavement is severely affected,

damages of the pavement are accelerated, and the service life of the

pavement structure is shortened.

At present, the crack repair technology of the asphalt pavement is mainly

based on material crack grouting, and a crack grouting material is used for

early maintenance of pavement cracks, so that not only the construction

process is simple, but also the construction cost is low. Various modified asphalts are used as a common crack grouting material, which is of very important practical significance in repairing the cracks. In the practical construction, due to the defects of poor percolation performance of the commonly used modified asphalt, a little asphalt is injected into the cracks in the pavement. Even if a slotting process is used, only the surface layer cracks of the asphalt pavement can be filled while the base layer cracks still exist, continue to accumulate water and continue to cause damages to the pavement, and therefore, the waterproof effect cannot be achieved very well.

SUMMARY

The objective of the invention is to provide a self-expanding rubber

asphalt material for crack grouting and filling of an asphalt pavement, which

can fill cracks and has the characteristics of large bonding strength, good low

temperature flexibility and the like.

To achieve the objective, the invention can adopt the following technical

scheme:

The self-expanding rubber asphalt material for crack grouting and filling

of the asphalt pavement disclosed by the invention is prepared from matrix

asphalt, waste tire rubber powder, an expansion material, a styrene

thermoplastic elastomer and diatomite in parts by weight through the following

method:

Ingredients: 100 parts of matrix asphalt, 10-15 parts of waste tire rubber

powder, 5-8 parts of the expansion material, 2-4 parts of the styrene

thermoplastic elastomer and 2-4 parts of diatomite.

The preparation method is as follows:

a first step, heating the matrix asphalt in a premixing tank to a

temperature of 180 °C to 190 °C , and then adding the waste tire rubber

powder to uniformly stir for 10-15 minutes;

a second step, throwing the styrene thermoplastic elastomer into the

premixing tank, stirring for 5-10 minutes, and uniformly mixing to obtain a

mixture;

a third step, grinding the mixture in a colloid mill for 2-3 times, and then

continuously stirring for 1-2 h after grinding;

and a fourth step, keeping the temperature of the colloid mill at 160 °C to

170 °C, sequentially adding the expansion material and the diatomite into the

colloid mill to continuously stir for 1-2 hours and performing cooling to obtain

the self-expanding rubber asphalt material for crack grouting and filling of the

asphalt pavement.

The matrix asphalt is AH-70 or AH-90 type asphalt.

The waste tire rubber powder is obtained by processing waste tires, with

a fineness of 400 meshes, and it is used to improve the high temperature

performance and elasticity of the filling material.

The expansion material is a SPA resin having a fineness of 400 meshes

to 600 meshes.

The styrene thermoplastic elastomer is a styrene-butadiene-styrene block

copolymer (SBS).

The diatomite is nano diatomite having a diameter ranging from 10 nm to

100 nm.

Before repairing the cracks in the pavement, it is very simple and

convenient to only heat the prepared filling material to a flowing state.

The invention adopts the waste rubber powder, the expansion material,

the styrene thermoplastic elastomer and the diatomite to perform compound

modification on the matrix asphalt, and the prepared self-expanding rubber

asphalt material for crack grouting and filling of the asphalt pavement asphalt,

while used for early repair for the cracks in the pavement, has the following

advantages:

1. Excellent self-expanding performance

The expansion material and the diatomite in the filling material swell in

water under the action of water accumulated in the cracks, thereby filling the

void caused by the continued damages of the pit, inhibiting the shrinkage of

the material, achieving the elastic sealing effect on the cracks, and effectively

achieving the waterproof effect.

2. Excellent tensile properties and resilience properties

The addition of waste tire rubber powder and SBS can make the filling

material have high tensile ability and resilience ability, thereby avoiding the

breakage of the waterproof layer, flexural fatigue or premature aging under a

high-stress state due to the fact the cracking stress of the base layer is

transmitted to the waterproof layer.

3. Excellent bonding properties

The compound modification of the raw materials used makes strong

adhesion between the asphalt and the surface of the substrate, and

overcomes the crack filling failure, due to insufficient adhesion, of the

common filling material.

4. Excellent high and low temperature performance

The addition of rubber powder greatly improves the high temperature

performance of the filling material, and overcomes the defect that the high

temperature performance of the common asphalt is not good; the expansion

material also acts as a modifier, which greatly changes the low temperature

flexibility of the material and ensures that the material can adapt to influences

caused by temperature changes.

DESCRIPTION OF THE INVENTION

The invention will be more fully understood from the following description

through specific embodiments of the invention to facilitate understanding by

those skilled in the art; the materials used in the invention are all commercially

available.

Example 1 preparation of self-expanding rubber asphalt material for crack

grouting and filling of asphalt pavement.

Preparation of materials: 100 parts of matrix asphalt (AH-70 or AH-90

type), 12 parts of waste tire rubber powder with a fineness of 400 meshes, 7

parts of expanded material (SPA resin with a fineness of 400 meshes to 600

meshes), 3 parts of SBS, and 3 parts of diatomite (nano diatomite having a

diameter ranging from 10 nm to 100 nm).

Preparation steps were as follows:

step 1, the matrix asphalt was heated in a premixing tank to a

temperature of 180 °C to 190 °C , and then the waste tire rubber powder was

added to uniformly stir for 10-15 minutes;

step 2, the SBS was continuously added into the premixing tank, stirred

for 5-10 minutes, and uniformly mixed to obtain a mixture;

step 3, the mixture was grinded in a colloid mill for 2-3 times, and then

continuously stirred for 1-2 hours after grinding;

and step 4, the temperature of the colloid mill was kept at 160 °C to

170 °C, the expansion material and the diatomite were sequentially added into

the colloid mill to continuously stir for 1-2 hours and cooling was performed to

obtain the self-expanding rubber asphalt material finished product for crack

grouting and filling of the asphalt pavement.

Example 2 preparation of crack grouting and filling material for cracks in

common rubber asphalt pavement

Preparation of materials: 100 parts of matrix asphalt (AH-70 or AH-90

type), 12 parts of waste tire rubber powder with a fineness of 400 meshes, 3

parts of SBS, and 3 parts of diatomite.

Preparation steps were as follows:

step 1, the matrix asphalt was heated in a premixing tank to a

temperature of 180 °C to 190 °C , and then the waste tire rubber powder was

added to uniformly stir for 10-15 minutes; step 2, the SBS was continuously added into the premixing tank, stirred for 5-10 minutes, and uniformly mixed to obtain a mixture; step 3, the mixture was grinded in a colloid mill for 2-3 times, and then continuously stirred for 1-2 hours after grinding; and step 4, the temperature of the colloid mill was kept at 160 C to

170 C, the diatomite was added into the colloid mill to continuously stir for 1-2

hours and cooling was performed to obtain the crack grouting and filling

material for cracks in common rubber asphalt pavement.

Example 3 performance detection

The performance effects of Example 1 and Example 2 were tested

according to the performance indexes in "Pavement Rubber Asphalt Potting

Sealant" (JT/T 740-2009). The test results were shown in the following table.

It can be seen from the test results that the invention adopts compound

modified asphalt including waste tire rubber powder, SBS and expansion

material as a pavement crack grouting and filling material, and under the

condition that all performances can be satisfied, the expansion material can

further fill gaps in the base layer and the surface layer. The cracks are

elastically sealed, and the waterproof effect is prominent, so that further

damages to the pavement are avoided.

Claims

1. A self-expanding rubber asphalt material for crack grouting and filling

of an asphalt pavement, characterized by being prepared from matrix asphalt,

waste tire rubber powder, an expansion material, a styrene thermoplastic

elastomer and diatomite in parts by weight through the following method:

ingredients: 100 parts of matrix asphalt, 10-15 parts of waste tire rubber

powder, 5-8 parts of the expansion material, 2-4 parts of the styrene

thermoplastic elastomer and 2-4 parts of diatomite; and the preparation

method is as follows: step 1, heating the matrix asphalt in a premixing tank to

a temperature of 180 C to 190 C, and then adding the waste tire rubber

powder to uniformly stir for 10-15 minutes; step 2, throwing the styrene

thermoplastic elastomer into the premixing tank, stirring for 5-10 minutes, and

uniformly mixing to obtain a mixture; step 3, grinding the mixture in a colloid

mill for 2-3 times, and then continuously stirring for 1-2 hours after grinding;

and step 4, keeping the temperature of the colloid mill at 160 C to 170 C,

sequentially adding the expansion material and the diatomite into the colloid

mill to continuously stir for 1-2 hours and performing cooling to obtain the self

expanding rubber asphalt material for crack grouting and filling of the asphalt

pavement.

2. The self-expanding rubber asphalt material for crack grouting and

filling of the asphalt pavement according to Claim 1, wherein the matrix

asphalt is AH-70 or AH-90 type asphalt.

3. The self-expanding rubber asphalt material for crack grouting and

filling of the asphalt pavement according to Claim 1, wherein the waste tire rubber powder is obtained by processing waste tires, with a fineness of 400 meshes.

4. The self-expanding rubber asphalt material for crack grouting and

filling of the asphalt pavement according to Claim 1, wherein the expansion

material is a SPA resin having a fineness of 400 meshes to 600 meshes.

5. The self-expanding rubber asphalt material for crack grouting and

filling of the asphalt pavement according to Claim 1, wherein the styrene

thermoplastic elastomer is a styrene-butadiene-styrene block copolymer

(SBS).

6. The self-expanding rubber asphalt material for crack grouting and

filling of the asphalt pavement according to Claim 1, wherein the diatomite is

nano diatomite having a diameter ranging from 10 nm to 100 nm.

FIGURES OF THE SPECIFICATION

1/1

Performance Evaluation Indexes Example 1 Example 2 Indexes Low-temperature tensile passed passed passed 2021101186

test Cone penetration (0.1 45 52 30-70 mm)

Softening point (℃) 87 81 ≥80

Flowing value (mm) 2.5 3.7 ≤5 Elastic recovery 63 58 30-70 (25℃) %

Figure 1.