What are the technical properties of asphalt and what indicators are used to express them

Technical properties of asphalt 1. Viscous viscosity is the ability of bitumen to resist deformation or block plastic flow.

2. Plastic plasticity refers to the ability of asphalt to be deformed without destruction when it is subjected to external force, and when the external force is withdrawn, it can maintain the deformation obtained.

3. Temperature sensitivity.

Temperature sensitivity refers to the degree to which the viscosity and plasticity of asphalt change with temperature. Asphalt does not have a fixed melting point, when the temperature rises, the plasticity of asphalt increases, the viscosity decreases, and it gradually softens from solid or semi-solid to viscous liquid; When the temperature decreases, the viscosity of the asphalt increases, the plasticity decreases, and the viscous flow state changes to a solid state.

The asphalt softening point is an important indicator to reflect the temperature sensitivity of asphalt, which indicates the temperature of asphalt from the old state to the viscous flow state, the higher the temperature, the smaller the temperature sensitivity, and this state transition will occur when the ambient temperature is high.

4. Atmospheric stability.

Atmospheric stability refers to the ability of petroleum bitumen to maintain stable performance under the long-term combined action of temperature, sunlight, air and water.

There are three major indicators of asphalt: penetration is the degree of softness and hardness at a certain temperature.

The softening point can be used indirectly to determine the range of its use.

Elongation measures the magnitude of external force and the ability to heal after being stressed.

The penetration is also an indicator of the grade.

There are penetration, softening point, ductility, wax content, etc.

The grade of petroleum asphalt is divided according to the penetration degree, such as No. 70 Liliang Pa this green, its penetration degree is between 60-80, No. 90 asphalt, its penetration degree is between 80-100. The grade of petroleum asphalt is mainly divided according to the penetration index of asphalt, the larger the grade, the smaller the viscosity, the better the plasticity, the greater the temperature sensitivity, and the longer the service life.

Extended information: 1. There are many grades of road petroleum asphalt, which are mainly used for road pavement or workshop ground and other projects, and are generally mixed into asphalt concrete.

Asphalt mixture or asphalt mortar, etc. Road petroleum asphalt can also be used as sealing materials, binders and asphalt coatings. At this time, it is advisable to choose road petroleum asphalt with greater viscosity and high softening point, such as 60 A.

2. Construction petroleum asphalt has large viscosity and good heat resistance, but small plasticity, and is mainly used to manufacture linoleum.

Oiled paper, waterproof coatings.

and asphalt glue. Most of them are used in roof and underground waterproofing, trench waterproofing, anti-corrosion and pipeline anti-corrosion projects. For oak Xun roofing waterproofing.

engineering, care should be taken to prevent excessive softening.

According to the high temperature season test, the surface temperature of the asphalt roof is 25 30 higher than the local maximum temperature, in order to avoid summer flow, the softening point of the asphalt material used for the roof should be more than 20 higher than the maximum temperature that the roof may reach on this land under the local temperature.

For example, the temperature of asphalt roofing in a certain area can reach 65, and the asphalt softening point should be above 85. However, the softening point should not be too high, otherwise the low temperature in winter is prone to hard brittleness and even cracking, and for some parts that are not easily affected by temperature, larger grades of asphalt can be selected.

3. The temperature stability of waterproof and moisture-proof petroleum asphalt is good, and it is especially suitable for coating materials for linoleum and adhesive materials for building roofs and underground waterproofing.

No. 3 bitumen has a general temperature sensitivity and a softer texture, which is used for general temperatures.

waterproofing of the lower parts of the interior and underground structures; No. 4 asphalt is less temperature sensitive and is used for waterproofing of gently sloping roofs that can be walked in general areas; No. 5 asphalt has low temperature sensitivity and is used for roof waterproofing in general areas with exposed roofs or high temperatures; No. 6 asphalt has the least temperature sensitivity and soft texture, except for general areas, it is mainly used for roofing and other waterproof and moisture-proof projects in cold areas.

Three major indicators of asphalt:

1.Penetration:

At the specified temperature of 25, the depth (1 10mm is one degree) of the standard needle with a specified mass of 100g penetrated into the asphalt sample within 5s of the specified time is expressed. The greater the penetration, the softer the asphalt and the less viscosity.

2.Ductility: The ductility meter is used to measure, and the asphalt sample is made into a figure-8 standard test mold, and the elongation length when the pull-off is broken at the specified tensile speed (5cm min) and the specified temperature (25), which is expressed in cm. The larger the ductility value, the better the plasticity.

3.Softening point:

The asphalt sample was measured by the global method, and the asphalt sample was loaded into a copper ring of specified size (diameter 16mm, height 6mm), and a standard steel ball was placed on the sample, which was immersed in water and heated at a specified speed (5 min) to soften the asphalt and sag. The softening point is the temperature at which the sag is reached. The higher the softening point, the better the heat resistance.

Hope it helps.

The three major indicators point to penetration, ductility and softening point.

Penetration is simply hardness, ductility has low temperature ductility (5 degrees) and high temperature ductility (25 degrees) and 10 degrees 15 degrees, characterizing the plasticity of asphalt, softening point is a high temperature index, temperature sensitivity is characterized by penetration index, viscosity is generally characterized by 60 degrees dynamic viscosity.

The grade of petroleum bitumen is mainly divided according to its quality indicators such as penetration, elongation and softening point.

The asphalt grade is the degree of penetration, 70, which represents the penetration between 60 and 80, and the penetration of 90 represents the penetration between 80 and 100, the smaller the penetration, the better the high temperature performance of asphalt, 70 asphalt is smaller than 90 asphalt, so the high temperature performance of 70 asphalt is better than that of 90 asphalt.

The grade of petroleum asphalt is divided according to the penetration degree, such as No. 70 asphalt, which has a penetration degree between 60-80, and No. 90 asphalt, which has a penetration degree between 80-100.

The hot-mix asphalt concrete mixture is divided into four types according to the maximum particle size of the aggregate, including coarse-grained, medium-grained, fine-grained and sand-grained, and AK series suitable for anti-skid surface paving.

The maximum particle size of asphalt concrete surface aggregate should be gradually increased from top to bottom. The maximum particle size of the asphalt mixture aggregate in the upper layer should not exceed 1 2 of the layer thickness, and the maximum particle size of the aggregate of the middle and lower layers and the connecting layer should not exceed 2 3 of the layer thickness. The asphalt concrete surface course that adopts double-layer or three-layer structure should have one layer and more than one layer is the type dense graded asphalt concrete mixture.

High temperature stability (rutting resistance), low temperature stability (cracking resistance), water stability, fatigue resistance, aging resistance, construction performance, specific content of the landlord can refer to Shen Jin'an's "asphalt and asphalt mixture road performance", this book is also a classic book in the industry.

The main technical properties of petroleum asphalt are viscosity, plasticity, temperature stability, atmospheric stability, etc. Viscosity: expressed in terms of penetration or relative viscosity, plasticity:

1. Viscosity: Viscosity is a characteristic that reflects the internal resistance of asphalt materials to its relative flow, and the larger the penetration value, the smaller the viscosity of solid and semi-solid asphalt.

2. Plasticity: plasticity refers to the property of asphalt that is deformed and not damaged under the action of external force. The greater the elongation of petroleum asphalt, the better the plasticity.

3. Temperature sensitivity: Temperature sensitivity refers to the properties of the viscosity and plasticity of petroleum asphalt that change with the rise and fall of temperature. The higher the softening point, the less temperature-sensitive the asphalt is.

4. Atmospheric stability: Atmospheric stability refers to the performance of petroleum asphalt to resist aging under the long-term action of atmospheric comprehensive factors. The larger the penetration ratio after evaporation, the better the atmospheric stability of the asphalt and the higher the durability of the asphalt.

Petroleum asphalt is used in road construction, waterproofing materials, oils and fuels, adhesives and adhesives

1. Road construction: Petroleum asphalt is one of the most commonly used materials in road construction. As a covering layer on the surface of the road, it can provide waterproof, compressive and anti-slip properties, while also reducing noise and prolonging the service life of the road.

2. Waterproof materials: Petroleum asphalt is widely used in the waterproof layer of buildings and infrastructure because of its viscosity and durability. It can be used as a coating, film or hot melt material in waterproofing projects such as roofs, walls, basements, tunnels, etc.

3. Oil and fuel: Petroleum asphalt can be processed into lighter petroleum products, such as gasoline, diesel and aviation fuel, which can be used as fuel for vehicle drives and machine combustion.

4. Adhesives and adhesives: Petroleum asphalt is widely used as adhesives and adhesives because of its adhesion to rock barriers. It can be used for the bonding of wood, metal and other materials, and plays an important role in the manufacture of tapes, glues and other products.

The three major indicators of asphalt are penetration, softening point, and ductility.

The penetration degree indicates the viscosity of the asphalt, the larger the index, the lower the viscosity of the asphalt, and the higher the grade of the asphalt;

The softening point indicates the thermal stability of the asphalt, and the higher the softening point, the better the thermal stability of the asphalt. The softening point also indicates the isoradical adhesion temperature of the asphalt, which means that the higher the softening point, the higher the temperature required for the asphalt to achieve the same viscosity;

The ductility represents the plastic deformation capacity of asphalt, and the ductility obtained when the test temperature is low reflects the low-temperature performance of asphalt, and the larger the low-temperature ductility value, the better the low-temperature performance of asphalt.

1. Penetration degree.

At the specified temperature and time, a standard needle of a certain mass is attached perpendicularly penetrating the depth of the asphalt specimen to indicate.

2. Ductility. The length of the asphalt specimen of the specified form is expressed in cm when it is stretched at a certain speed at a certain temperature to the time of disconnection.

3. Softening point.

The asphalt sample is in the metal ring of the specified size, and the metal steel ball of the specified size and quality is placed on it, and it is placed in water or glycerin, heated at the specified speed, until the temperature when the steel ball sinks to the specified distance, which is expressed as expressed.