CN102558884A - Rock asphalt modified asphalt and preparation method thereof - Google Patents

Abstract

The invention provides modified asphalt, which comprises 85-90% of matrix asphalt and 10-15% of natural rock asphalt in percentage by weight, wherein the content of asphalt in the natural rock asphalt is 75-80%. The invention also provides a preparation method of the modified asphalt, which comprises the following steps: heating the matrix asphalt to 150-160 ℃; slowly adding the natural rock asphalt into the matrix asphalt under stirring, wherein the weight percentage of the matrix asphalt to the natural rock asphalt is 85-90 percent and 10-15 percent, and the asphalt content in the natural rock asphalt is 75-80 percent; after the raw materials are completely mixed, grinding and mixing are carried out, and then the finished product is obtained.

Description

Rock asphalt modified asphalt and preparation method thereof

technical field

The invention relates to a modified asphalt, in particular to a new modified asphalt and a preparation method thereof. the

Background technique

In recent years, the rapid development of China's social economy has brought about a rapid increase in the demand for transportation and dynamic transportation. The traffic volume, load capacity and axle load have increased significantly, and there are certain overloading phenomena. Most parts of China are hot in summer and rainy in the south. These unfavorable traffic load characteristics and climatic conditions have caused the asphalt pavement to face a severe test. Ordinary asphalt pavement has serious early failures such as rutting, water damage, low temperature cracking, and potholes soon after it is opened to traffic. wait. The damage done cannot be underestimated. the

At present, there are modified asphalt in the market, such as SBS (styrene-butylene-styrene), SBR (styrene-butadiene rubber) and BRA (buton rock asphalt). Wherein SBS is currently the most widely used in the market, the largest product, but the price is too high floating space is limited, SBR production cost is also relatively high, difficult to promote, BRA (CN102276187 Chinese invention patent application discloses a kind of buton rock asphalt Modified asphalt mixture), due to the low asphalt content of Buton rock asphalt (20%-30%), the addition amount is up to 50%, and the cost saving and data are not really ideal in the actual implementation of the market. On the contrary, it consumes energy. Due to its low content of asphalt, it cannot be wet mixed, and it cannot be added by traditional methods. The only way to add it is to use semi-mechanical and semi-manual additions in the process of clinker production in a mixing building. The addition process is cumbersome and the amount of addition is large. The clinker needs to be added to mix time, consume energy, and reduce the output relatively. According to the data reflected by the market, it is not ideal, and the problems caused are many. The price of use is not high, so it is rare to see someone use it in the market now. the

Contents of the invention

The present invention aims to solve the problems in the aforementioned prior art and provide a new modified asphalt. the

The invention provides a modified asphalt, which comprises 85-90% of matrix asphalt and 10-15% of natural rock asphalt, wherein the content of asphalt in the natural rock asphalt is 75-80%. the

The average particle size of the natural rock asphalt powder is 80-200 mesh. the

The present invention also provides the preparation method of described modified asphalt, it comprises the steps:

1) Heat the base asphalt to 150-160°C;

2) Slowly add natural rock asphalt into base asphalt under stirring, wherein base asphalt in weight percentage: natural rock asphalt=85-90%: 10-15%, wherein the bitumen content in the natural rock asphalt is 75% -80%;

3) After the raw materials are completely mixed, they are ground and then mixed to obtain the finished product. the

The preparation method as described above, wherein step 3) after grinding, transport the mixed asphalt to another grinder, so as to repeat the grinding twice. the

Detailed ways

The present invention is further illustrated below with non-limiting examples. The base bitumen used in the examples is Maoming Petrochemical AH-70 heavy rubber, and the natural rock bitumen used is selected from Trinidad and Tobago lake bitumen, Utah natural rock bitumen and/or Chinese Qingchuan rock asphalt etc. Rock asphalt contains 75-80% asphalt, and the mesh number of powder is 80-200 mesh. the

The production process is as follows, 3 batches, wherein the weight percentages of matrix asphalt and natural rock asphalt are 85%: 15%; 88%: 12%; 90%: 10%. the

a. First, heat the base asphalt AH-70 to 150-160 degrees, transport it to a container of a mixer, and add natural rock asphalt at the same time, and slowly add it while stirring until the two raw materials are added according to the ratio;

b. After continuing to mix for 10 minutes, the two raw materials are mixed, and then filtered and transported to the grinder for grinding. The grinding process is transported to another mixer for mixing, and the grinding is repeated twice, and then it can be transported to the storage tank for storage; The product obtained by mixing these two raw materials through the above-mentioned simple processing and grinding is the new modified asphalt. the

In order to check the compatibility and storage stability of the components of the modified asphalt of the present invention, the base asphalt and the natural rock asphalt were kept warm in the processing tank for 1H, 2H, 3H, 4H and about 15H before starting construction on the height of the inner surface of the processing tank respectively. 3 and the lower 1/3 of the sample, the measured softening point difference is not very different, to evaluate the stability of natural rock asphalt, the test results show that because the rock asphalt itself has a higher softening point than 100 As the time prolongs, rock asphalt is better compatible with matrix asphalt, and there is no obvious segregation. It can be seen that rock asphalt dissolves better in matrix asphalt with the extension of holding time. the

According to the design results of mineral material composition, the asphalt ratio was initially selected as 4.2%, 4.5%, 4.8%, 5.1%. 5.5% to carry out the standard Marshall test results, the optimum asphalt ratio was 4.8%, and the asphalt film thickness was 8.0um at this time. The Marshall modulus is 5.2KN/mm, and the asphalt saturation is 67.5%, which shows that the asphalt mixture has formed an embedded and compact frame structure, which meets the Marshall technical standard of the standard densely graded asphalt mixture. the

Marshall test and implementation data show that the modified asphalt provided by the present invention has several times higher adsorption energy than ordinary asphalt on the surface of rock materials, has good anti-stripping performance, high anti-rutting ability at softening point, high tensile strength and anti-aging Oxidation performance and water damage resistance can improve the driving comfort of the road, prolong the service life of the road, and the characteristics of environmental protection and regeneration have good promotion and application value. the

The new modified asphalt enhances the anti-fatigue performance of the mixture, and the life of the improved asphalt pavement increases by about 30%. If the asphalt pavement damage in actual engineering is caused by the four ruts, the service life of the road can usually be increased by 100-200%. the

The new modified asphalt has strong anti-aging ability and anti-microbial erosion effect, and good weather resistance, which makes the asphalt pavement durable. the

The high-temperature stability, water stability and low-temperature performance of the mixture after using the new modified asphalt all meet and exceed the technical requirements of the relevant indicators in the "Technical Specifications for Construction of Highway Asphalt Pavement (JTGF40-2004). the

The environmental protection performance of new modified asphalt, the usual ordinary asphalt concrete pavement and SBS modified pavement (styrene) require repair or reconstruction after a long time and long-term wear and tear of vehicles. A large area of land is piled up or landfilled, which causes environmental pollution, and the new modified asphalt (adding natural rock asphalt) is a polymer chemical produced under natural conditions, with a high content of nitrogen atoms, and nitrogen atoms in the amount of The form of functional groups is not easy to age, so it can be re-used by milling and returning to the furnace during repair or transformation; this protects the environment and reduces costs. the

Compared with SBS modified asphalt, the production of new modified asphalt does not require a large amount of equipment investment and complicated production processes, and is convenient for transportation and storage. There is no need to add any links from the mixing building to road construction, thus greatly saving construction costs and energy. consume. the

The new modified asphalt uses natural rock asphalt polymer (75%-80% asphalt content) mineral material as the main raw material, and because the chemical structure is similar to asphalt, it has very good compatibility with asphalt and can form an "interaction" with matrix asphalt. Through the three-dimensional grid", so its modified technical performance is particularly superior. In the new modified asphalt prepared by adding natural rock asphalt, the base asphalt only acts as a medium, which greatly improves the performance of asphalt and asphalt mixture. The modification process is simple, the economic benefit is obvious, and it has the potential value of renewable development. the

The present invention produces for the main product SBS of the market, only SBS has comparability in the domestic market product at present, according to the market implementation report no matter price energy consumption data the present invention all occupies certain advantage, can save under any link that has been added 15-20% cost. the

Claims (4)

1. modifying asphalt, it comprises the matrix pitch of 85-90% by weight percentage, the natural rock asphalt of 10-15%, wherein said natural rock asphalt medium pitch content is 75-80%.

2. modifying asphalt as claimed in claim 1, the median size of wherein said natural rock asphalt powder is: the 80-200 order.

3. modified asphalt preparation method, it comprises the steps:

1) matrix pitch is heated to 150-160 ℃;

2) under agitation natural rock asphalt slowly is added in the matrix pitch, wherein matrix pitch by weight percentage: natural rock asphalt=85-90%: 10-15%, wherein said natural rock asphalt medium pitch content is 75-80%;

3) raw materials mix fully after, remix after grinding, after must finished product.

4. process for preparing modified asphalt as claimed in claim 3, wherein step 3) is ground the back conveying and is mixed into another mill, repeats to grind twice with this.