CN103496888B - Modified asphalt concrete capable of reducing temperature of road surface - Google Patents

Abstract

The invention provides a modified asphalt concrete with the function of cooling the road surface, which is made of the following raw materials in parts by weight: 100 parts of mineral material, 3-9 parts of asphalt, 0.3-3 parts of iron ore powder, and 0.01-0.06 parts of coupling agent parts; the iron ore powder is a mixture of hematite powder and goethite powder in a mass ratio (0.5-2): 1, and the coupling agent is a silane coupling agent or a titanate coupling agent , the gradation type of the mineral material is GAC-13 type, AM-13 type, AC-13 type, SMA-13 type, OGFC-13 type or superpave type. The modified asphalt concrete of the invention can effectively reduce the temperature of the pavement, fundamentally solve the rutting problem of the asphalt pavement, increase the service life of the pavement, slow down the urban heat island effect, and has broad application value and development prospect.

Description

A Modified Asphalt Concrete with Pavement Cooling Function

technical field

The invention belongs to the technical field of road asphalt concrete, and in particular relates to a modified asphalt concrete with the function of cooling the road surface.

Background technique

At present, the pavement structure of urban roads in my country is basically asphalt pavement. Almost all the heat absorbed by ordinary asphalt concrete pavement at high temperature is stored in the form of sensible heat, which causes the pavement temperature to rise rapidly and the high temperature lasts for a long time, thus causing high temperature diseases, such as the urban "heat island effect" caused by high temperature and the structural load of asphalt pavement. Decreased capacity and frequent occurrence of rutting diseases. How to develop and utilize new cooling materials to reduce the temperature of asphalt concrete pavement, thereby improving the anti-rutting ability of the pavement, increasing the service life of the pavement, and alleviating the urban heat island effect is a sustainable development problem facing urban roads in the future.

In order to alleviate the urban heat island effect and reduce high-temperature rutting, the main technical measures currently adopted are the "passive" method of changing the structure of asphalt pavement, the "active" method of applying cooling materials on the road surface, and improving the high-temperature stability of asphalt mixture. A large number of engineering examples show that the above measures cannot fundamentally solve the problems of urban heat island effect and high temperature rutting. Although it has achieved certain results, there are still many problems. For example, traditional and passive measures to improve the performance of asphalt mixture can prolong the quality and service life of the road surface and reduce the temperature of the road surface, but the cooling effect is limited. Cooling coatings have high cost, poor durability, low reuse rate, complicated construction process, pollute the environment and affect the performance of pavement, etc.

Therefore, there is an urgent need to develop a new type of asphalt concrete with pavement cooling function, which can effectively reduce the temperature of the pavement, improve the anti-rutting ability of the pavement, increase the service life of the pavement, and alleviate the urban heat island effect.

Contents of the invention

The technical problem to be solved by the present invention is to provide a modified asphalt concrete with the function of cooling the road surface in view of the above-mentioned deficiencies in the prior art. The asphalt concrete can effectively reduce the temperature of the road surface, improve the anti-rutting ability of the road surface, increase the service life of the road surface, and alleviate the urban heat island effect, and has broad application value and development prospect.

In order to solve the above-mentioned technical problems, the technical solution adopted in the present invention is: a modified asphalt concrete with road surface cooling function, which is characterized in that it is made of the following raw materials in parts by weight: 100 parts of mineral aggregate, 3 to 9 parts of asphalt, 0.3-3 parts of iron ore powder, 0.01-0.06 parts of coupling agent; the iron ore powder is a mixture of hematite powder and goethite powder in a mass ratio (0.5-2): 1, and the coupling agent The coupling agent is a silane coupling agent or a titanate coupling agent, and the gradation type of the mineral material is GAC-13, AM-13, AC-13, SMA-13, OGFC-13 or superpave type.

The above-mentioned modified asphalt concrete with road surface cooling function is characterized in that it is made of the following raw materials in parts by weight: 100 parts of mineral aggregate, 3-6.4 parts of asphalt, 0.4-1.6 parts of iron ore powder, and 0.02 parts of coupling agent ~0.05 parts.

The above-mentioned modified asphalt concrete with road surface cooling function is characterized in that it is made of the following raw materials in parts by weight: 100 parts of mineral aggregate, 4.8 parts of asphalt, 0.96 part of iron ore powder, and 0.03 part of coupling agent.

The above-mentioned modified asphalt concrete with road surface cooling function is characterized in that the asphalt is road petroleum asphalt, coal tar pitch, SBS modified asphalt, SBR modified asphalt or natural rubber modified asphalt.

The above-mentioned modified asphalt concrete with road surface cooling function is characterized in that the mass ratio of hematite powder and goethite powder in the iron ore powder is 1:1.

The above-mentioned modified asphalt concrete with road surface cooling function is characterized in that the particle diameters of the hematite powder and goethite powder are both less than 0.075 mm.

The parts by weight may be weight measurement units such as gram, liang, jin, kilogram, ton.

The preparation method of the modified asphalt concrete with pavement cooling function of the present invention is:

Step 1. Add the iron ore powder into the coupling agent and stir evenly, then place it in a drying oven, and dry it at a temperature of 160°C to 180°C for 2h to 3h to obtain a modified powder;

Step 2: Heat the asphalt to 140°C-170°C, heat the aggregate in the mineral aggregate to 180°C-200°C, then add the heated asphalt to the heated aggregate and mix for 90 seconds, and finally add it to the mineral aggregate The slag powder and the modified powder described in step 1 are continuously stirred for 90s to 100s to obtain the modified asphalt concrete with the function of cooling the road surface.

The construction technique of the bituminous concrete with pavement cooling function of the present invention is:

Step 1. Remove the soil and sundries on the road surface to be paved, ensure that the road surface to be paved has no obvious defects such as polishing, deformation, and mesh cracking, and spread emulsified asphalt.

Step 2: Transport the modified asphalt concrete of the present invention to the construction site at a temperature of 160° C. to 180° C. Pay attention to maintaining the temperature and preventing segregation.

Step 3: Pour the modified asphalt concrete of the present invention into a paver for paving, and use a road roller to compact the paved asphalt concrete.

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

1. Hematite and goethite are added to the modified asphalt concrete of the present invention. With the change of ambient temperature, the internal stress of hematite and goethite changes, and the spontaneous polarization is enhanced, which promotes the water molecules in the environment It decomposes to form hydroxide ions, and at the same time consumes part of the energy. The hydroxide ions formed by the decomposition and the water molecules in the air and acid gas molecules generate negative ions under the action of the electric field, and at the same time lose part of the energy, so that the temperature around the asphalt concrete will increase accordingly. Change, so as to achieve the function of reducing the temperature of the road surface. Therefore, the present invention has a good function of reducing the temperature of the road surface, and can effectively reduce the temperature of the road surface by 5°C to 10°C.

2. Hematite and goethite are added to the modified asphalt concrete of the present invention. Goethite and hematite are rich in mineral resources and have a wide range of sources, and are suitable for popularization and use.

3. The preparation method and construction process of the modified asphalt concrete of the present invention are simple and convenient, and are suitable for large-scale production.

4. The modified asphalt concrete of the present invention can effectively reduce the temperature of the road surface, improve the anti-rutting ability of the road surface, increase the service life of the road surface, alleviate the urban heat island effect, and has broad application value and development prospect.

The present invention is described in further detail below in conjunction with embodiment.

Detailed ways

The mineral aggregate in the modified asphalt concrete of the present invention meets the relevant technical requirements of JTG-F40-2004 "Technical Specifications for Construction of Highway Asphalt Pavement". Granite aggregate, basalt aggregate, diabase aggregate or limestone aggregate, mineral powder is limestone powder with particle size less than 0.075mm.

Example 1

The modified asphalt concrete with road surface cooling function in this embodiment is made of the following raw materials in parts by weight: 100 parts of mineral aggregate, 4.8 parts of asphalt, 0.96 part of iron ore powder, and 0.03 part of coupling agent; A mixture of iron ore powder and goethite powder in a mass ratio of 1:1; the asphalt is SBS modified asphalt, the coupling agent is silane coupling agent KH550, the hematite powder and goethite The particle size of the mineral powder is less than 0.075mm, and the gradation type of the mineral material is GAC-13 (see Table 1 for the specific gradation composition).

Table 1 GAC-13 type gradation composition

The preparation method of the present embodiment modified asphalt concrete is:

Step 1. Add the iron ore powder into the coupling agent and stir evenly, then place it in a drying oven, and dry it at a temperature of 160°C for 3 hours to obtain a modified powder;

Step 2: Heat the asphalt to 140°C, heat the aggregate in the mineral aggregate to 200°C, then add the heated asphalt to the heated aggregate and mix for 90 seconds, finally add the mineral powder in the aggregate and step 1 The modified powder described in , continue to mix for 100s to obtain the modified asphalt concrete with the function of pavement cooling.

Example 2

The modified asphalt concrete with road surface cooling function in this embodiment is made of the following raw materials in parts by weight: 100 parts of mineral aggregate, 6.4 parts of asphalt, 1.6 parts of iron ore powder, and 0.05 part of coupling agent; A mixture of iron ore powder and goethite powder in a mass ratio of 1:1; the asphalt is SBR modified asphalt, the coupling agent is silane coupling agent KH560, the hematite powder and goethite The particle size of the mineral powder is less than 0.075mm, and the gradation type of the mineral material is AM-13 (see Table 2 for the specific gradation composition).

Table 2AM-13 type gradation composition

The preparation method of the present embodiment modified asphalt concrete is:

Step 1. Add the iron ore powder into the coupling agent and stir evenly, then place it in a drying oven, and dry it for 2 hours at a temperature of 160°C to obtain a modified powder;

Step 2: Heat the asphalt to 170°C, heat the aggregate in the mineral aggregate to 200°C, then add the heated asphalt to the heated aggregate and mix for 90 seconds, finally add the mineral powder in the aggregate and step 1 The modified powder described in , continue to mix for 90s to obtain the modified asphalt concrete with the function of pavement cooling.

Example 3

The modified asphalt concrete with the function of pavement cooling in this embodiment is made of the following raw materials in parts by weight: 100 parts of mineral aggregate, 3 parts of asphalt, 0.4 part of iron ore powder, and 0.02 part of coupling agent; A mixture of iron ore powder and goethite powder in a mass ratio of 1:1; the pitch is coal tar pitch, the coupling agent is titanate coupling agent TMC201, and the hematite powder and goethite The particle size of the mineral powder is less than 0.075mm, and the gradation type of the mineral material is AC-13 (see Table 3 for the specific gradation composition).

Table 3 AC-13 type gradation composition

The preparation method of the present embodiment modified asphalt concrete is:

Step 1. Add the iron ore powder into the coupling agent and stir evenly, then place it in a drying oven, and dry it for 2 hours at a temperature of 160°C to obtain a modified powder;

Step 2: Heat the asphalt to 170°C, heat the aggregate in the mineral aggregate to 180°C, then add the heated asphalt to the heated aggregate and mix for 90 seconds, finally add the mineral powder in the aggregate and step 1 The modified powder described in , continue to mix for 100s to obtain the modified asphalt concrete with the function of pavement cooling.

Example 4

The modified asphalt concrete with road surface cooling function in this embodiment is made of the following raw materials in parts by weight: 100 parts of mineral aggregate, 9 parts of asphalt, 3 parts of iron ore powder, and 0.06 part of coupling agent; A mixture of iron ore powder and goethite powder in a mass ratio of 2:1; the asphalt is SBS modified asphalt, the coupling agent is titanate coupling agent TMC201, the hematite powder and The particle size of the goethite powder is less than 0.075mm, and the gradation type of the mineral material is SMA-13 (see Table 4 for the specific gradation composition).

Table 4 SMA-13 type gradation composition

The preparation method of the present embodiment modified asphalt concrete is:

Step 1. Add the iron ore powder into the coupling agent and stir evenly, then place it in a drying oven, and dry it at a temperature of 180°C for 2 hours to obtain a modified powder;

Step 2: Heat the asphalt to 140°C, heat the aggregate in the mineral aggregate to 180°C, then add the heated asphalt to the heated aggregate and mix for 90 seconds, finally add the mineral powder in the aggregate and step 1 The modified powder described in , continue to mix for 90s to obtain the modified asphalt concrete with the function of pavement cooling.

Example 5

The modified asphalt concrete with road surface cooling function in this embodiment is made of the following raw materials in parts by weight: 100 parts of mineral aggregate, 3 parts of asphalt, 0.3 part of iron ore powder, and 0.01 part of coupling agent; A mixture of iron ore powder and goethite powder in a mass ratio of 0.5:1; the asphalt is road petroleum asphalt, the coupling agent is titanate coupling agent TMC101, and the hematite powder and goethite The particle size of the iron ore powder is less than 0.075mm, and the gradation type of the mineral material is OGFC-13 type (see Table 5 for the specific gradation composition).

Table 5 OGFC-13 type gradation composition

The preparation method of the present embodiment modified asphalt concrete is:

Step 1. Add the iron ore powder into the coupling agent and stir evenly, then place it in a drying oven, and dry it for 2 hours at a temperature of 160°C to obtain a modified powder;

Step 2: Heat the asphalt to 140°C, heat the aggregate in the mineral aggregate to 180°C, then add the heated asphalt to the heated aggregate and mix for 90 seconds, finally add the mineral powder in the aggregate and step 1 The modified powder described in , continue to mix for 100s to obtain the modified asphalt concrete with the function of pavement cooling.

Example 6

The modified asphalt concrete with road surface cooling function in this embodiment is made of the following raw materials in parts by weight: 100 parts of mineral aggregate, 5.6 parts of asphalt, 1.6 parts of iron ore powder, and 0.03 part of coupling agent; A mixture of iron ore powder and goethite powder in a mass ratio of 1:1; the asphalt is natural rubber modified asphalt, the coupling agent is titanate coupling agent TMC101, and the hematite powder The particle size of goethite powder and goethite powder are both less than 0.075mm, and the gradation type of the mineral material is superpave type (see Table 6 for the specific gradation composition).

Table 6 Superpave type gradation composition

The preparation method of the present embodiment modified asphalt concrete is:

Step 1. Add the iron ore powder into the coupling agent and stir evenly, then place it in a drying oven, and dry it for 3 hours at a temperature of 180°C to obtain a modified powder;

Step 2: Heat the asphalt to 170°C, heat the aggregate in the mineral aggregate to 200°C, then add the heated asphalt to the heated aggregate and mix for 90 seconds, finally add the mineral powder in the aggregate and step 1 The modified powder described in , continue to mix for 90s to obtain the modified asphalt concrete with the function of pavement cooling.

According to the relevant technical requirements of the standard JTG E20-2011 "Test Regulations for Asphalt and Asphalt Mixtures in Highway Engineering" issued by the Ministry of Communications, the performance of the modified asphalt concrete in Examples 1 to 6 of the present invention is verified by the following tests.

1. Road performance test

The rutting test, low temperature beam bending test (-10°C), freeze-thaw splitting test and water immersion Marshall test were carried out on the modified asphalt concrete of Examples 1 to 6 of the present invention to test the road performance of the modified asphalt concrete, and Compared with ordinary asphalt concrete without adding hematite and goethite, the test results are shown in Table 7.

Table 7 The road performance test data of modified asphalt concrete of the present invention

It can be seen from Table 7 that the modified asphalt concrete of the present invention meets the relevant requirements of the Ministry of Communications standard JTGF40-2004 "Technical Specifications for Construction of Highway Asphalt Pavement", and its high-temperature performance, low-temperature performance, water stability and other indicators are significantly higher than ordinary asphalt concrete. , indicating that the road performance of the asphalt concrete of the present invention is superior.

2. Rutting plate temperature test

Using the modified asphalt concrete of Examples 1 to 6 of the present invention to prepare rutting slabs with a size of 30cm×30cm×5cm, place the rutting slabs in an outdoor environment at the same time, test the temperature of the surface of the rutting slabs, and simulate the temperature change of the asphalt concrete road surface , and compared with ordinary asphalt concrete without adding hematite and goethite, the test results are shown in Table 8.

Table 8 The temperature test data of the rutting slab of the modified asphalt concrete of the present invention

It can be seen from Table 8 that the modified asphalt concrete of the present invention can significantly reduce the surface temperature of the asphalt pavement, thereby effectively preventing the formation of high-temperature rutting and other diseases on the pavement, has good road performance, can effectively absorb a large amount of heat, and can alleviate the urban heat island effect. Ecological and sustainable features.

The above descriptions are only preferred embodiments of the present invention, and do not limit the present invention in any way. All simple modifications, changes and equivalent changes made to the above embodiments according to the technical essence of the invention still belong to the protection scope of the technical solution of the invention.

Claims (5)

1. there is a modified asphalt concrete for road surface cooling function, it is characterized in that, be made up of the raw material of following weight part: mineral aggregate 100 parts, pitch 3 ~ 9 parts, powdered iron ore 0.3 ~ 3 part, coupling agent 0.01 ~ 0.06 part; Described powdered iron ore be ground hematite and pyrrhosiderite powder in mass ratio (0.5 ~ 2): 1 mixture mixed, described coupling agent is silane coupling agent or titanate coupling agent, and the gradation types of described mineral aggregate is GAC-13 type, AM-13 type, AC-13 type, SMA-13 type, OGFC-13 type or superpave type; The particle diameter of described ground hematite and pyrrhosiderite powder is all less than 0.075mm.

2. a kind of modified asphalt concrete with road surface cooling function according to claim 1, is characterized in that, be made up of the raw material of following weight part: mineral aggregate 100 parts, pitch 3 ~ 6.4 parts, powdered iron ore 0.4 ~ 1.6 part, coupling agent 0.02 ~ 0.05 part.

3. a kind of modified asphalt concrete with road surface cooling function according to claim 2, is characterized in that, be made up of the raw material of following weight part: mineral aggregate 100 parts, pitch 4.8 parts, powdered iron ore 0.96 part, coupling agent 0.03 part.

4. a kind of modified asphalt concrete with road surface cooling function according to claim 1,2 or 3, is characterized in that, described pitch is bi tumenf orr oad, coal-tar pitch, SBS modifying asphalt, SBR modifying asphalt or natural rubber modifying asphalt.

5. a kind of modified asphalt concrete with road surface cooling function according to claim 1,2 or 3, is characterized in that, in described powdered iron ore, the mass ratio of ground hematite and pyrrhosiderite powder is 1: 1.