Federal Agency for Education Moscow State Academy of Fine Chemicals
technology named after M.V. Lomonosov
Department of Technology of Petrochemical Synthesis and Artificial Liquid Fuel named after. A.N. Bashkirova
Likhterova N.M., Nikolaev A.I.
PROPERTIES AND METHODS FOR DETERMINING THEIR CHARACTERISTICS.
Guidelines for performing laboratory work
Moscow, 2008
BBK 35.514ya73 UDC 541,127:665.642
Likhterova N.M., Nikolaev A.I.
BITUMEN. PROPERTIES AND METHODS FOR DETERMINING THEIR CHARACTERISTICS.
Guidelines for performing laboratory work M, MITHT im. M.V. Lomonosova, 2008, 35 p.
The manual contains a section devoted to the properties of bitumen, as well as a section that presents methods for determining the physical and mechanical characteristics that determine these properties.
Intended for 4th - 6th year students studying in the areas of higher engineering school 072000 “Standardization and Certification”, 250400 - “Chemical technology of natural energy carriers and carbon materials”, as well as in the master’s degree 550808 - “Chemical technology of natural energy carriers and carbon materials”.
Reviewer: senior researcher TsKP MITHT im. M.V. Lomonosova, Ph.D. Gorodsky S.N.
© MITHT im. M.V. Lomonosova, 2008
1. Petroleum bitumens | |
1.1. Properties of bitumen | |
1.2. Raw materials for the production of petroleum bitumen | |
2. Modern domestic petroleum bitumens | |
3. Experimental methods for determining physical | |
chemical characteristics of petroleum bitumen | |
3.1. Method for determining needle penetration depth | |
according to GOST 11501-78 | |
3.2. Method for determining softening temperature by | |
ring and ball according to GOST 11506-73 | |
3.3. Fraas brittleness temperature method | |
according to GOST 11507-78 | |
3.4. Method for determining the change in mass after heating | |
according to GOST 18180-72 | |
3.5. Method for determining elongation according to GOST 111505-75 | |
4. Calculation methods for determining physical and mechanical properties | |
characteristics of bitumen |
1. Petroleum bitumens.
Natural bitumen has been known to mankind for many thousands of years. In addition to their natural origin, bitumen can be obtained from the processing of oil, shale, peat and coal. In the 20th century, with the development of the oil production and oil refining industry, the production and consumption of bitumen produced from petroleum feedstock increased. The scope of their application is quite wide. So they are used as construction and waterproofing materials in the construction of building foundations and roofs (insulating and roofing bitumen), a binder when laying roads (road bitumen), etc. It should be noted that for the successful use of bitumen they must have a certain set of properties.
1.1. Properties of bitumen. 1.1.1. Viscosity.
At high temperatures, bitumens approach the properties of a liquid, and at low temperatures they acquire the properties of a solid. For road bitumens, viscosity as an indicator of performance properties is important in two cases. During the period of mixing bitumen with mineral materials, they must have a sufficiently low viscosity to ensure ease and efficiency of mixing and laying the mixture into the pavement. During the operation of the road surface, bitumen must have a very high viscosity at elevated temperatures, providing it with the necessary strength. Therefore, viscosity is one of the main characteristics of the structural and mechanical properties of bitumen. The viscosity of bitumen varies widely depending on the chemical composition and temperature. The quantitative ratio of asphaltenes and oils has a significant influence on the viscosity of bitumen. As the amount of asphaltenes increases, the viscosity increases. To increase the durability of the road surface, it is important that the viscosity of the bitumen changes to a lesser extent in the temperature range at which the surface is operated.
A marking feature of viscous road bitumen, which indirectly determines their viscosity, is the depth of needle penetration (penetration) into the bitumen at temperatures of 25 and 0°C. The higher the asphaltene content in the bitumen, the lower the needle penetration depth. The depth of penetration of the needle indirectly characterizes the performance qualities of bitumen such as hardness, strength and heat resistance.
The marking feature of liquid road bitumen is the indicator of conditional viscosity, characterized by the expiration time in
seconds 50 ml of bitumen through a 5 mm hole at a temperature of 60°C and determined using a standard viscometer.
1.1.2. Softening temperature.
The temperature at which bitumens turn from a relatively solid state into a liquid state is conventionally called the softening temperature. The softening point is also a conditional indicator of the viscosity of bitumen at higher temperatures. More viscous bitumens have a higher softening point. At the same needle penetration depth, bitumens with a higher softening temperature are also more heat-resistant. Bitumen with a low softening point have low strength at elevated temperatures.
The softening temperature depends on the composition of the bitumen. The higher the ratio of asphaltenes to the content of liquid components of bitumen - resins and oils - it is higher.
For the quality of bitumen, the relationship between the depth of penetration of the needle and the softening temperature is of great importance. More valuable are bitumens that, at a given softening temperature, have a higher needle penetration depth. This means that bitumens are relatively less susceptible to temperature changes.
Thus, the viscosity of bitumens has a significant impact on the properties of the asphalt concrete mixture during mixing, laying and compaction, as well as on construction and technical properties of asphalt concrete. The high viscosity of bitumens increases the strength, water resistance and heat resistance of asphalt concrete, but bitumens with increased viscosity cover the surface of mineral materials worse, therefore bitumens should be used with a certain viscosity and at certain heating temperatures, taking into account the climatic conditions of the construction area, the type, brand and type of asphalt concrete, the automobile category roads.
This indicator serves for the operational assessment of bitumen and relates the softening temperature and needle penetration depth. The penetration index (I.P.) is expressed as an abstract number determined by the formula:
AND . P .= 1 + 30 50 A − 10
A = 2.9031− logP
T − 25
where P is the depth of penetration of the needle at 25°C, 0.1 mm;
T - softening temperature, °C.
The penetration index characterizes the colloidal properties of bitumen, their plastic properties and their dependence on temperature.
According to the penetration index, bitumens are divided into three groups:
1. bitumens and IP 2 (sol), which do not have a dispersed phase or contain highly pentized asphaltenes (bitumens from cracking residues or coal tar pitches). The elasticity of such bitumen (ductility at 25° C) is close to zero;
2. bitumen and IP from -2 to +2 (sol-gel) there are elements for the formation of a spatial coagulation framework with layers of dispersed medium that prevents the aging of bitumen (bitumens for road construction);
3. bitumens with IP 2 are gels and are prone to aging. Requirements of modern GOST 22245-90 for viscous road
bitumen provides for a change in IP from -1 to +1.
1.1.4. Extensibility.
The extensibility of bitumens is assessed by their ability to stretch into a thread of a certain length under the influence of load.
The extensibility of bitumens depends on their temperature, group composition and structure. Bitumen with a high content of resins with an optimal content of oils and asphaltenes have greater plasticity. With increasing temperature, the extensibility of bitumen increases. Bitumen with a greater needle penetration depth also have greater extensibility. With an increase in the content of solid paraffins in bitumen, the extensibility of bitumen decreases.
The extensibility of bitumen indirectly characterizes their adhesion to mineral materials. With increasing extensibility, the adhesion of bitumen to mineral materials increases, which is explained by the significant content of aromatic compounds and resins in bitumen. The extensibility of bitumen at 25° C also characterizes the degree of structuring of the bitumen and the type of its dispersed structure.
One of the most important properties of asphalt concrete is closely related to the extensibility of bitumen at low temperatures - its deformability at low operating temperatures. Insufficient deformability leads to rapid destruction of asphalt concrete and cracks appear in the coatings. Increasing the extensibility of bitumen at subzero temperatures is the most important task for researchers and engineers.
1.1.5. Brittleness temperature.
The lowest temperature at which bitumen, under given test conditions, loses its viscoplastic properties and becomes brittle is called the brittleness temperature.
The brittleness temperature is one of the most important indicators of the quality of road, roofing and a number of other bitumens, characterizing the performance of bitumen-containing materials at low temperatures. A possibly lower brittleness temperature of bitumen is desirable, since such bitumen has better plastic properties, and road or roofing coatings work better in harsh climates and cold weather. Bitumen coatings with a high brittleness temperature at low temperatures chip, crack and quickly collapse.
The presence of paraffin-naphthenic and monocyclic aromatic compounds determines the low brittleness temperature of bitumen.
The temperature interval between the softening temperature and the brittleness temperature is called the plasticity interval. Bitumen with a wide range of plasticity (more than 70°C) have increased deformability, resistance to cracking at low temperatures and resistance to shear at elevated summer temperatures. The larger the temperature range in which bitumen is in an elastic-viscous state, the better its performance properties. Such bitumen usually also exhibits good adhesion to the surface of the mineral material.
1.1.6. Adhesion to the surface of mineral materials
(adhesion).
The ability of bitumen to firmly adhere to the surface of mineral particles prevents spalling of the mineral material from the road surface monolith and ensures its frost and water resistance.
The adhesion of bitumen to mineral material depends on the properties of bitumen and mineral materials, as well as on the external conditions in which mixing is carried out and the road surface is operating.
The adhesion of bitumen is determined by the polarity of the molecules of the mixture components. In bitumen, the molecules of asphaltenes and asphaltotenic acids and their anhydrides have significant polarity.
Bitumen adheres well to the surface of mineral materials of carbonate and basic rocks and poorly to the surface of mineral materials of acidic (SiO2 content more than 65%) rocks (granite).
The adhesion of bitumen increases with increasing temperature, and the presence of moisture on the surface of the mineral material sharply reduces the adhesion of bitumen.
Water-soluble compounds include compounds that are extracted with water in the form of a solution or released from bitumen in the form of emulsions. As a rule, these are low-molecular compounds (acids or alkalis) and some salts of organic acids.
The presence of water-soluble compounds in bitumen leads to the fact that when bitumen comes into contact with water, extraction of these substances occurs. The process of washing out individual components from the composition of the bitumen binder contributes to the formation of microcracks (voids) in the road surface, which in turn leads to its destruction in winter due to the wedging effect of water in a crystalline state. This may expose mineral material and then crumble out of the road surface.
1.1.8. Aging.
Aging is usually called a set of irreversible changes in the chemical composition, structure and properties of bitumen that occur when bitumen is exposed to various factors - temperature, light, air, water, mineral materials and mechanical loads.
As a result of aging, bitumens increase their viscosity and fragility. An increase in viscosity occurs due to a change in the group composition of bitumen - resins transform into asphaltenes, asphaltenes partially transform into carbenes and carboids, and the content of aromatic compounds decreases. When bitumen is stored in the open air for a long time, cracks and peeling appear on its surface as a result of oxidation, and adhesion to mineral materials deteriorates. Such changes in the physical properties and chemical composition of bitumen are associated primarily with the processes of oxidation and polymerization occurring in bitumen and to a lesser extent depend on the evaporation of light fractions.
A characteristic of bitumen's resistance to aging (stability) under conditions of long-term storage at elevated temperatures is an increase in the softening temperature after heating.
Bitumen with a higher initial viscosity are subject to less changes from atmospheric factors than bitumen with a lower initial viscosity. The intensity of aging increases in bitumen when heated in the presence of mineral materials that act as catalysts. Also, the intensity of aging of bitumen in an asphalt concrete pavement is significantly influenced by the volume and structure of the pores of asphalt concrete. Large volume of open
9 (communicating) pores, promoting increased circulation of air and water, intensifies the aging processes of bitumen. In dense asphalt concretes, characterized by closed pores, bitumen aging is less intense. The thinner the asphalt concrete layer, the greater the intensity of bitumen aging.
1.1.9. Fire safety of bitumen.
When bitumens are heated, gaseous products are released, which can ignite in the presence of an open flame. To protect bitumens from fire during their manufacture and use, it is necessary to take into account the flash and self-ignition temperatures.
The flash point is the temperature at which the gaseous products of heated bitumen form a mixture with the surrounding air that ignites when a flame is applied to it.
The auto-ignition temperature is the temperature of gaseous products released from heated bitumen, which, when mixed with air after ignition, burn for at least 5 s.
In practice, the flash point and self-ignition temperature are used to judge the fire hazard and expected losses from the evaporation of bitumen.
1.2. Raw materials for the production of petroleum bitumen.
The main raw materials for the production of bitumen are the residues of vacuum distillation of oil - tars, as well as by-products of oil production - deasphalting asphalts, that is, asphalt-resinous substances deposited from tars, usually with liquid propane. They are also called precipitated bitumen. In some cases, cracked residues from a thermal cracking unit are used to produce bitumen.
It should be noted that to obtain high-quality bitumen with high thermal stability and good binding properties, it is advisable to use tars of heavy oils with a naphthenoaromatic base, containing a lot of asphalt-resinous substances. However, to produce bitumen on a large scale, it is necessary to use mass-produced oils. For example, the possibility of obtaining bitumen from oils, the characteristics of which are presented in Table 1, was studied for 22 fields in Turkmenistan.
Table 1 Composition of oils from Turkmenistan fields.
Oil fields | |||||||||||||||||||||||||||
Kotur - Tepe | |||||||||||||||||||||||||||
Kotur - Tepe | Komsomol | ||||||||||||||||||||||||||
Zap. Cheleken | Dagadzhik | Western | Central | Eastern | Oval-Toval | Barca-Gelmes | West | Central |
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Paraffin | |||||||||||||||||||||||||||
Asphaltene | |||||||||||||||||||||||||||
Continuation of Table 1 |
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Oil fields | |||||||||||||||||||||||||||
Kotur - Tepe | |||||||||||||||||||||||||||
Pribalkhansky | Gograndag - | ||||||||||||||||||||||||||
West | Oriental | Buruns-kaya | Monjucly | Reed ski | Is it Karadash? | ||||||||||||||||||||||
Paraffin | |||||||||||||||||||||||||||
asphaltenes | |||||||||||||||||||||||||||
Using the classification of oils developed by the BashNIINP Institute (classification 1), according to the content of asphaltenes (A), resins (C) and paraffins (P), the results presented in
Back in ancient times. Capitals such as Babylon or Assyria used bitumen as a building material as far back as 3 thousand years BC. e. It perfectly served as a cementing or waterproofing material.
This substance can be divided into several groups, which are determined based on the organic composition of the building material. As for tar bitumen, this includes all types of tar and pitches. So, they are tar and natural organic.
The following can be classified as bituminous:
- Natural bitumen. Such a substance comes in liquid and solid form, consisting mostly of organic substances and their non-metallic derivatives. This substance is obtained as a result of the natural processing of oil with oxidizing polymers. Mainly, bitumen of natural origin is found in places of oil deposits or forms special asphalt swamps. By the way, such rocks are rare, and in most cases they penetrate the so-called sedimentary rocks;
- Asphalt powder. Bitumen is a substance that can be stored in rocks such as limestone. In further processing, this substance is extracted or used as asphalt powder;
- Artificial (petroleum) bitumen. Material obtained from petroleum refining. The technology used for processing distinguishes the following types of bitumen: residual, oxidized, cracked;
- Tar bitumen. It is extracted by squeezing oil fractions from fuel oil. This substance is an excellent binder and the basis for the production of any type of bitumen.
Physico-mechanical features of construction bitumen
Areas of use
Of course, bitumen (as building materials) has become extremely widespread in hydraulic engineering, road or industrial and commercial construction. Today they are used in the form of roofing materials, promote commercial construction and are used in road repair work.
The binding organic substance combines well and interacts with rubber or polymer, which can only improve the overall quality of bitumen products in accordance with the requirements and standards of modern construction.
The video shows the preparation and use of road bitumen grades BND 90/130 and BND 60/90:
Composition, structure and characteristics of the material
The average composition of bitumen varies in the following ratio of elements: 75-80% carbon, 10-15% hydrogen, up to 10% sulfur and up to 5% oxygen. The solid part of this building material is hydrocarbons and their derivatives at the molecular level. In its structure, this substance resembles a colloidal system in which asphaltenes are dispersed in a dispersion medium of oil and resin.
These elements that make up bitumen also determine a number of properties and characteristics that the material has. For example, an increased percentage of asphaltenes and resins entails an increase in hardness, density and melting point.
Otherwise, that is, with an increased level of oils, the bitumen softens and becomes lighter and more fusible. According to GOST 22245 90, the oil and resin content in bitumen must be average and balanced, otherwise it will acquire excessive plasticity and viscosity.
The degree of bitumen viscosity directly depends on the degree of heating. Increasing the temperature will increase the viscosity, and decreasing it will make the material harder. At zero or sub-zero temperatures, bitumen becomes a rather brittle material.
Bitumen also has another important property: it is not soluble in water, but is completely or partially soluble in acidic substances such as chloroform, benzene or carbon disulfide, and has a low heat capacity. According to the certificate of conformity, bitumen must have a density that is within 1.5 g/cm3. But when calculating the total mass of bitumen, the weight of 1 liter will be calculated through the density of 1 kg/m3.
Bitumen has a wide range of features and useful properties that bring it to the leading level among other binding building materials. Hydrophobicity and solubility in most modern solvents, softening and increase in viscosity with gradual heating, plasticity and adhesion - all these properties should be possessed by high-quality bitumen.
What is penetration index
Penetration is an indicator that characterizes the properties of bitumen in solid form. In other words, this is the depth to which the needle penetrates at a bitumen temperature of 25 degrees. To determine this coefficient, a special device, Penetrometer, is used.
The measurement process involves measuring the penetration depth of a calibrated needle, taking into account a given period of time and a constant load. This measurement is made at a given bitumen temperature and calculates the immersion depth of the needle, which is measured in a ratio of 1 to 10 mm. Among three similar measurements, the average is selected, which is the penetration index.
Table of comparative characteristics of construction grades of bitumen
Table of comparative characteristics of roofing bitumen grades
It is worth mentioning another qualitative indicator that perfectly characterizes bitumen as a road (liquid or viscous), construction insulation and roofing material - this is the specific and volumetric gravity. According to all technological and construction standards, the specific gravity of bitumen should be no more than 1 g/cm. cube at its boiling point. All these indicators must be indicated in the product passport.
What hazard class does bitumen have?
The main problem that arises with is the need to transport it in liquid form at the appropriate temperature. Since the temperature in the tank must be higher than 100 degrees, but lower than the ignition temperature, bitumen is given hazard class 9, which is called “Liquid at elevated temperature. Highly flammable." This substance has a high heat capacity, so its transportation must be approached with great care.
Finally
is a high-quality binder that is widely used in construction. This substance is suitable for various types of work. Transportation of bitumen is a rather labor-intensive process that requires not only special tanks, but also a technical passport.
Do not also forget that bitumen is an organic-based substance that has its own shelf life of 1 calendar year. Due to some difficulties during transportation, it can be given a 4, although this material is simply irreplaceable in construction.
A few more words about construction bitumen:
OIL ROAD VISCOUS BITUMENS
Specifications
GOST
22245-90
STATE STANDARD OF THE USSR
1.1. Viscous petroleum road bitumens are produced by oxidation of products of direct distillation of oil and selective separation of petroleum products (deasphalting asphalts, selective purification extracts), as well as by compounding the indicated oxidized and non-oxidized products or in the form of a residue of direct distillation of oil in accordance with the requirements of this standard according to the technological regulations approved in in the prescribed manner. It is allowed to use the cracking residue as a component of the oxidation feedstock.
1.2. Characteristics
1.2.1. Depending on the depth of needle penetration at 25 °C, viscous road petroleum bitumen is produced in the following grades: BND 200/300, BND 130/200, BND 90/130, BND 60/90, BND 40/60, BN 200/300, BN 130 /200, BN 90/130, BN 60/90.
The scope of application of bitumen in road construction is in accordance with Appendix 1.
|
Name |
Standard for bitumen |
|||||||||
|
OKP 02 5612 0113 |
OKP 02 5612 0112 |
OKP 02 5612 0111 |
OKP 02 5612 0203 |
OKP 02 5612 0202 |
||||||
|
Depth |
According to GOST 11501 |
|||||||||
|
at 25 °C |
||||||||||
|
at 0 °C, |
||||||||||
|
Softening temperature along the ring and ball, °C, not lower |
According to GOST 11506 |
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|
Tensile strength, cm, not less |
According to GOST 11505 |
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|
at 25 °C |
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|
at 0 °C |
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|
Brittleness temperature, °C, not higher |
According to GOST 11507 |
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|
Flash point, °C, not lower |
According to GOST 4333 |
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|
Change in softening temperature after heating, °C, no more |
According to GOST 18180 According to GOST 11506 |
|||||||||
|
Index |
-1.0 to +1.0 |
-1.5 to + 1.0 |
According to Appendix 2 |
|||||||
1.2.2. In terms of physical and chemical parameters, bitumens must comply with the requirements and standards specified in table 1
1.2.3. Safety requirements
1.2.3.1. Viscous road petroleum bitumens are flammable substances with a flash point above 220 °C and a minimum auto-ignition temperature of 368 °C.
1.2.3.2. The maximum permissible concentration of bitumen hydrocarbon vapors in the air of the working area is 300 mg/m 3 - in accordance with GOST 12.1.005 . The content of hydrocarbon vapors in the air is determined according to GOST 12.1.014-84.
1.2.3.3. Bitumen are low-hazard substances and, in terms of the degree of impact on the human body, belong to the 4th hazard class according to GOST 12.1.007 .
1.2.3.4. When working with bitumen, personal protective equipment should be used in accordance with standard industry standards approved in accordance with the established procedure.
1.2.3.5. The room in which bitumen is worked must be equipped with supply and exhaust ventilation.
1.2.3.6. If small amounts of bitumen catch fire, it should be extinguished with sand, felt felt or a foam fire extinguisher. Developed bitumen fires should be extinguished with a foam jet.
1.3. Nature protection requirements
1.3.1. Effective measures to protect the natural environment include sealing equipment and preventing bitumen spills.
1.3.2. Waste from bitumen production (oxidation gases) is neutralized by combustion in an afterburner.
2. ACCEPTANCE
2.1. Viscous road petroleum bitumen is accepted in batches.
A batch is considered to be any quantity of bitumen that is uniform in terms of quality and accompanied by one quality document.
2.2. Sample size - according to GOST 2517.
2.3. If unsatisfactory test results are obtained for at least one of the indicators, repeated tests are carried out on a newly selected sample taken from the same batch.
The results of repeated tests apply to the entire batch.
2.4. The manufacturer determines the elongation at 0 °C and the change in softening temperature after heating periodically at least once every 10 days, and the flash point at least once a month.
2.5. If unsatisfactory results of periodic tests are received, the manufacturer transfers the tests for this indicator to the acceptance category until positive results are obtained for at least three batches in a row.
3. CONTROL METHODS
3.1. Samples of viscous road bitumen - according to GOST 2517. The mass of the combined sample of each grade of bitumen must be at least 0.5 kg.
3.2. The brittleness temperature of BN grade bitumen can be determined using a nomogram
3.3. The change in softening temperature after heating is calculated as the difference in softening temperatures determined according to GOST 11506 before and after the heating test according to GOST 18180 .
4. MARKING, TRANSPORTATION AND STORAGE
4.1. Labeling, transportation and storage of bitumen - in accordance with GOST 1510.
4.2. Viscous road bitumen belongs to the 9th transport hazard class according to GOST 19433-88 (subclass 9.1, category 9.13, classification code 9133).
5. MANUFACTURER WARRANTY
5.1. The manufacturer guarantees that the quality of bitumen meets the requirements of this standard subject to the conditions of transportation and storage.
The production technology guarantees the adhesion of bitumen grades BND with reference marble according to sample No. 2 according to GOST 11508-74 using method A.
5.2. The guaranteed shelf life of bitumen is one year from the date of manufacture.
Nomogram for determining the brittleness temperature of road surfaces
bitumen grades BN
Nomogram for determining the brittleness temperature of road surfaces
bitumen grades BN
Bitumen is an indispensable component of construction. Thanks to its unique characteristics, bitumen has firmly established itself in the construction industry. Its practicality, durability and low cost leave no chance for alternative building materials.
Characteristics of bitumen
Bitumen is an asphalt-like material produced artificially. It is the final product of processing natural bitumen, residues after processing coal, oil, shale resins and peat extracts.
Depending on the components and characteristics, several types of bitumen are distinguished:
- Natural bitumen is a by-product during the extraction of petroleum products from various rocks. They are characterized by high resistance to acids, alkalis, and water.
- Construction bitumen is a product of petroleum distillation and mixing with various construction components (oil production residues, asphalt, etc.). For working with roofing materials and for high-rise work, bitumen of the BNK 45/180, BNK 45/90, BNK 90/40 or BNK 90/30 brands is usually used. They are characterized by high resistance to moisture and high temperatures. Compared to roofing bitumen, construction bitumen has greater fire resistance.
- Road bitumen is the most popular type of bitumen. The main brands of road bitumen: BND 40/60, BND 60/90, BND 90/130, BND 130/200 and BND 200/300. It is characterized by a high penetration coefficient (penetration into the environment). Bitumen with high penetration rates are relevant for northern regions, and with lower ones - for southern regions.
The characteristics of bitumen are constantly changing and improving. So, in order to improve the qualities of this building material, various artificial additives are added to it, which specifically enhance certain characteristics. Typically, such chemical ingredients increase resistance to sudden temperature changes, cold or heat.
The main characteristics by which the quality of bitumen can be assessed:
Extensibility,
Temperature indicators for fragility,
Softening temperature indicators,
Penetration level.
Accordingly, chemical additives for bitumen are aimed at improving these characteristics. The price of bitumen directly depends on the quality and intended use of the building material. Optimized brands that are resistant to heavy loads and have good elongation will cost more. As a rule, all the necessary indicators are reflected on the bitumen labeling.
Application of bitumen
The type of bitumen determines the scope of its application in construction.
Natural bitumen
Today, construction or road bitumen is very popular. But despite the obvious superiority of artificial bitumen in mass construction, natural bitumen is actively used in other industrial sectors.
Natural bitumen with special characteristics (non-oxidized composition) is very popular for road construction in Western countries. Unoxidized high-quality bitumen can only be produced using new generation equipment.
There are a lot of similar industries in the West, which explains the difference in the demand for natural bitumen in the post-Soviet space and in Western countries. Every motorist can feel this difference by comparing the quality of the road surface.
Road bitumen
Road bitumen has proven itself when working in the most difficult and unfavorable conditions. It perfectly withstands heavy loads, which makes it an ideal material for the construction of road surfaces. It is widely used in the production of asphalt concrete and asphalt.
As a component of asphalt pavements, road bitumen acts as a binder, holding all the ingredients together. Thanks to its distinctive characteristics, crushed stone, river sand and the remaining ingredients of the asphalt mixture form a strong, homogeneous mass.
The density of bitumen divides it into two types:
- viscous,
- liquid.
Viscous bitumen is relevant as a binder for road construction or repair. Liquid bitumen is used to extend the construction period of road surfaces.
The quality and durability of the road surface largely depends on the characteristics of road bitumen and the degree of its compliance with GOST standards. The use of high-quality materials significantly increases the service life of roads, avoiding the appearance of cracks, potholes and similar defects. You can buy high-quality bitumen from the manufacturer or from direct suppliers.
Construction bitumen
Without construction bitumen, not a single foundation pouring, roofing or repair work is possible. Construction bitumen is obtained during oil refining and comes in two types: solid and liquid.
- The solid type of bitumen is convenient to transport, but it requires heating at the construction site. Softening of hard ingots is carried out using special equipment - bitumen cookers. The temperature of bitumen must be quite high in order to successfully use it for roofing or waterproofing.
- Liquid bitumen requires special transportation conditions - it is delivered to the construction site in a special bitumen truck, adapted for transporting dark oil products. The peculiarity of the liquid type of bitumen is that it must be used as quickly as possible. It is used for sealing joints on buildings, making bitumen mastics and roofing work.
___________________________________________________________________________
OIL ROAD VISCOUS BITUMENS
Specifications
GOST
22245-90
IPPUBLISHING STANDARDS
Moscow
1996
STATE STANDARD OF THE USSR UNION
Date of introduction 01.01.91
This standard applies to viscous road petroleum bitumen intended as a binder material for the construction and repair of road and airfield pavements. Mandatory quality requirements for petroleum road viscous bitumen are set out in paragraph 5.
1. TECHNICAL REQUIREMENTS
1.1. Viscous petroleum road bitumens are produced by oxidation of products of direct distillation of oil and selective separation of petroleum products (deasphalting asphalts, selective purification extracts), as well as by compounding the indicated oxidized and non-oxidized products or in the form of a residue of direct distillation of oil in accordance with the requirements of this standard according to technological regulations approved in the prescribed manner. It is allowed to use cracking residue as a component of oxidation feedstock.
1.2. Characteristics
1.2.1. Depending on the depth of penetration of the needle at 25 °C, viscous road petroleum bitumen is produced in the following grades: BND 200/300, BND 130/200, BND 90/130, BND 60/90, BND 40/60, BN200/300, BN 130/200, BN 90/130, BN 60/90.
The scope of application of bitumen in road construction is in accordance with.
-1.0 to +1.0
-1.5 to + 1.0
8.(Deleted, Amendment No. 1).
(Changed edition, Amendment No. 1).
1.2.2. In terms of physical and chemical indicators, bitumens must comply with the requirements and standards specified in.
1.2.3. Safety requirements
1.2.3.1. Viscous road petroleum bitumens are flammable substances with a flash point above 220 °C and a minimum auto-ignition temperature of 368 °C according to GOST 12.1.044-89.
1.2.3.2. The maximum permissible concentration of bitumen hydrocarbon vapors in the air of the working area is 300 mg/m 3 - in accordance with GOST 12.1.005. The content of hydrocarbon vapors in the air is determined according to GOST 12.1.014-84.
1.2.3.1, 1.2.3.2. (Changed edition, Amendment No. 1) .
1.2.3.3. Bitumen are low-hazard substances and the gradual impact on the human body belongs to the 4th hazard class according to GOST 12.1.007.
1.2.3.4. When working with bitumen, personal protective equipment should be used in accordance with standard industry standards approved in the prescribed manner.
1.2.3.5. The room in which bitumen is processed must be equipped with supply and exhaust ventilation.
1.2.3.6. When small amounts of bitumen catch fire, it should be extinguished with sand, felt felt or a foam extinguisher. Developed bitumen fires should be extinguished with a foam jet.
1.3. Nature protection requirements
1.3.1. Effective measures to protect the natural environment are sealing equipment and preventing bitumen spills.
1.3.2. Waste bitumen production (oxidation gases) is neutralized by combustion in an afterburner.
2. ACCEPTANCE
2.1. Viscous road petroleum bitumen is accepted in batches.
A batch is considered to be any quantity of bitumen that is uniform in terms of quality and accompanied by one quality document.
2.2. Sample size - according to GOST 2517.
2.3. If unsatisfactory test results are obtained for at least one of the indicators, repeated tests are carried out on a newly selected sample taken from the same batch.
The results of repeated tests apply to the entire batch.
2.4. Extensibility at 0° The manufacturer determines C and the change in the softening temperature after heating periodically at least once every 10 days, and the flash point at least once a month.
2.5. If unsatisfactory results of periodic tests are obtained, the manufacturer transfers the tests for this indicator to the acceptance category until positive results are obtained for at least three batches in a row.
3. CONTROL METHODS
3.1. Samples of viscous road bitumen - according to GOST 2517. The mass of the combined sample of each grade of bitumen must be at least 0.5 kg.
3.3 . The change in softening temperature after heating is calculated as the difference in softening temperatures determined according to GOST 11506 before and after heating testing according to GOST 18180.
4. MARKING, TRANSPORTATION AND STORAGE
4.1. Labeling, transportation and storage of bitumen - according to GOST 1510.
4.2. Viscous road bitumen belongs to the 9th transport hazard class according to GOST 19433-88 (subclass 9.1, category 9.13, classification code 9133).
(Introduced additionally, Amendment No. 1).
5. MANUFACTURER WARRANTY
5.1. The manufacturer guarantees that the quality of bitumen meets the requirements of this standard subject to the conditions of transportation and storage.
The production technology guarantees the adhesion of BND grade bitumen with standard marble according to sample No. 2 according to GOST 11508-74 using method A.
(Changed edition, Amendment No. 1).
5.2. The guaranteed shelf life of bitumen is one year from the date of manufacture.
ANNEX 1
AREA OF APPLICATION OF BITUMENS IN ROAD CONSTRUCTION
Table 2
| Road climate zone | Average monthly temperatures of the coldest time of the year,°C | Brand of bitumen. |
| Not higher - 20 | BND 90/130, BND 130/200, BND 200/300 |
|
| II and III | From - 10 to - 20 | BND 60/90, BND 90/130, BND 130/200, BND 200/300 |
| II, III, IV | From - 5 to - 10 | BND 40/60, BND 60/90, BND 90/130, BND 130/200, BN 90/130, BN 130/200, BN 200/300 |
| IV and V | Not lower than + 5 | BND 40/60, BND 60/90, BND 90/130, BN 60/90, BN 90/130 |
APPENDIX 2
Table for determining the bitumen penetration index
Table 3
| Softening temperature | ||||||||||||||||||
| Softening temperature ° WITH | Penetration index at needle penetration depth at 25 °C |
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| Softening temperature | Penetration index at needle penetration depth at 25 °C |
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DEVELOPERS V. V. Fryazinov, Ph.D. tech. sciences; I. I. Sherysheva; S.L.Alexandrova, Ph.D. chem. sciences; I, A. Chernobrivenko, T. P. Kamalova; V. M. Yumashev, Ph.D. technical sciences; I. A. Plotnikova, Ph.D. technical sciences; L. M. Gokhman, Ph.D. technical sciences; E. M. Gurariy, Ph.D. technical sciences; A. R. Davydova, Ph.D. tech. sciences 2. APPROVED AND ENTERED INTO EFFECT by Resolution of the USSR State Committee on Standards dated 02.12.90 No. 191 3. INSTEAD GOST 22245-76 4. REFERENCE REGULATIVE AND TECHNICAL DOCUMENTS
5. Change No. 1 Adopted by the Interstate Council for Standardization, Metrology and Certification (Minutes No. 8 of 10/12/95)
6. The validity period was lifted by decision of the Interstate Council for Standardization, Metrology and Certification (IUS 4-94) 7. REISSUE with Change No. 1, approved in October 1995 (IUS9-96) | |||||||||||||||||||||||||||||||||||||||||||||||||||||