Polymer Modified Bitumen
Polymer Modified Bitumen Description
Bitumen has been used for thousands of years and its importance as a valued engineering material continues to increase. The interest in the modification of bitumen using polymers, whether virgin, scrap, or polymer blends, is intense. The last two decades, in particular, have seen an increase in the number of academic groups studying polymer-modified bitumen, and correspondingly the peer-reviewed literature in the field has increased. Initially, studies on polymer modified bitumen (PMB) focused more on engineering and empirical measurements, e.g. aging and softening points. However, in recent years a plethora of techniques have been employed in the study of the effect of the addition of polymers on a range of bitumen properties, polymer—bitumen morphology, and polymer—bitumen interactions.
When a polymer is added to regular bitumen, it becomes more elastomeric, which provides it with additional elasticity. The polymer that is added is styrene butadiene styrene (SBS), which acts as a binder modification agent. The primary objective of SBS polymer modified bitumen is to provide extra life to the pavement, roads, and construction designs. Some of the qualities exhibited by PMB are:
- Higher rigidity
- Increased resistance to deformation
- Increased resistance to cracks and stripping
- Better water resistance properties
- High durability
Advantage of using polymer modified bitumen
- stronger road with increased marshall stability value and greater Rigidity.
- better resistance towards rainwater and water stagnation.
- no stripping and no potholes.
- Better resistance to permanent deformation
- reduction in pores in aggregate and hence less rutting and raveling.
- Much higher durability
Common types of Polymer Modified Bitumen
The following table lists some common asphalt cement and HMA modifiers and their general purpose/use.
| Type | General Purpose or Use | Generic Examples |
| filler | Fill voids and therefore reduce optimum asphalt content Meet aggregate gradation specifications Increase stability Improve the asphalt cement-aggregate bond | Mineral filler crusher fines lime Portland cement fly ash Carbon black |
| extender | Substituted for a portion of asphalt cement (typically between 20–35 % by weight of total asphalt binder) to decrease the amount of asphalt cement required | Sulfur Lignin |
| rubber | Increase HMA stiffness at high service temperatures Increase HMA elasticity at medium service temperatures to resist fatigue cracking Decrease HMA stiffness at low temperatures to resist thermal cracking (see Figure 2) | Natural Latex Synthetic latex (e.g., Polychloroprene latex) Block copolymer (e.g., Styrene-butadiene-styrene (SBS)) Reclaimed rubber (e.g., crumb rubber from old tires) |
| plastic | Polyethylene/polypropylene Ethylene acrylate copolymer Ethyl-vinyl-acetate (EVA) Polyvinyl chloride (PVC) Ethylene propylene or EPDM Polyolefin | |
| Rubber-Plastic Combinations | Blends of rubber and plastic | |
| Fiber | Improving tensile strength of HMA Mixtures Improving cohesion of HMA Mixtures Permit higher asphalt content without the significant increase in the drain down | Natural: Asbestos Rock wool Manufactured: Polypropylene Polyester Fiberglass Mineral Cellulose |
| Oxidant | Increase HMA stiffness after the HMA is placed | Manganese salts |
| Antioxidant | Increase the durability of HMA mixtures by retarding their oxidation | Lead compounds Carbon Calcium salts |
| Hydrocarbon | Restore aged asphalt cement to current specifications Increase HMA stiffness in general | Recycling and rejuvenating oils Hard and natural asphalts |
| Antistripping Agents | Minimize stripping of asphalt cement from aggregates | Amines Lime |
| Waste Materials | Replace aggregate or asphalt volume with a cheaper waste product | Roofing shingles Recycled Tires Glass |
Use as needed
While the benefits of using modified asphalts are widely acknowledged, not all asphalt mixes or treatments need to be modified. Each application should be evaluated to determine if the traffic loading, anticipated service life, environmental conditions, and desired performance justify the use of modifiers. Modified asphalts can be a good investment.
The rheological properties of conventional binders may be modified by the introduction of:
Elastomers;
Plastomers;
Crumb rubber;
The modification is costly and is normally justified when bituminous surfacing are subjected to severe conditions such as:
Steep gradients;
Very high road surface temperature;
High traffic loading; or
Heavily trafficked intersections.
Modification may also be advantageous for surfacing on highly flexible and cracked pavements, where an improvement in the rheological properties of the bitumen is required.
Use in such applications should be guided by expert opinion.
In addition to the primary aims above, the range of properties improved include
Durability;
Aggregate retention;
Resistance to permanent deformation;
Resistance to fatigue cracking;
Cohesion (internal strength);
Elasticity;
Viscosity less susceptible to temperature changes.
Modification agents
The primary aim of the modification of bitumen for use in structural layers is to increase the resistance of these layers to permanent deformation at high road temperatures without compromising the properties of these layers over the rest of the prevailing temperature range.
The use of polymer modified bitumen to obtain improved performance is rising as a result of increases in tire pressures, axle loads, and higher traffic volumes.
Improved performance can be achieved in two ways, both of which are aimed at reducing the permanent strain:
An increase in the elastic component with an associated reduction in the viscous component; and
Stiffening of the bitumen to reduce the total viscoelastic response of the layer.
The modification is achieved by the introduction of polymers (including crumb rubber), aliphatic synthetic wax, or naturally occurring hydrocarbons. Polymers can be broadly categorized as “elastomers” (sometimes referred to as thermoplastic elastomers) for improving the strength and elastic properties of a binder, and “customers” (sometimes referred to as thermoplastic polymers) for increasing the viscosity of the bitumen.
Performance Grade Bitumen
Performance Grade Bitumen Description
The performance grade bitumen is based on the evaluation of the material performance when in use, unlike being rational as in the viscosity grading system. The viscosity grading system is more into the experience-based method of grading. And this has proved to have excellent performance for over 20 years in US pavement construction.
The Superpave grading was developed as a part of a 5year strategic highway research planning (SHRP) from 1987 to 1992, to have a performance-based grading system for bitumen. These were developed based on the engineering features that will help in solving many of the engineering problems.
Penetration grading and viscosity grading are somewhat limited in their ability to fully characterize asphalt binders for use in HMA pavement. Therefore, as part of the Superpave research effort, new binder tests and specifications were developed to more accurately and fully characterize asphalt binders for use in HMA pavements. These tests and specifications are specifically designed to address HMA pavement performance parameters such as rutting, fatigue cracking, and thermal cracking.
Superpave Performance Grade Bitumen is based on the idea that an HMA asphalt binder’s properties should be related to the conditions under which it is used. For asphalt binders, this involves expected climatic conditions as well as aging considerations. Therefore, the PG system uses a common battery of tests (as the older penetration and viscosity grading systems do) but specifies that a particular asphalt binder must pass these tests at specific temperatures that are dependant upon the specific climatic conditions in the area of use. Therefore, a binder used in the Sonoran Desert of California/Arizona/Mexico would have different properties than one used in the Alaskan tundra. This concept is not new – the selection of penetration or viscosity graded asphalt binders follows the same logic – but the relationships between asphalt binder properties and conditions of use are more complete and more precise with the Superpave PG system. Information on how to select a PG asphalt binder for a specific condition is contained in the Superpave mix design method. Table 1 shows how the Superpave PG system addresses specific penetration, AC, and AR grading system general limitations.
Performance Grade (PG) bitumen is bitumen which is graded based on its performance at different temperatures. The Long-Term Pavement Performance(LTPP) has given certain algorithm to calculate the temperature of the pavement based on the temperature of the air above. From this, the highest and the lowest temperatures of the pavement is calculated and the bitumen that performs well in that temperature range is selected.
| Limitations of Penetration, AC and AR Grading Systems | Superpave Binder Testing and Specification Features that Address Prior Limitations |
|---|---|
| Penetration and ductility tests are empirical and not directly related to HMA pavement performance. | The physical properties measured are directly related to field performance by engineering principles. |
| Tests are conducted at one standard temperature without regard to the climate in which the asphalt binder will be used. | Test criteria remain constant, however, the temperature at which the criteria must be met changes in consideration of the binder grade selected for the prevalent climatic conditions. |
| The range of pavement temperatures at any one site is not adequately covered. For example, there is no test method for asphalt binder stiffness at low temperatures to control thermal cracking. | The entire range of pavement temperatures experienced at a particular site is covered. |
| Test methods only consider short-term asphalt binder aging (thin film oven test) although long-term aging is a significant factor in fatigue cracking and low temperature cracking. | Three critical binder ages are simulated and tested:Original asphalt binder prior to mixingwith aggregate.Aged asphalt binder after HMAproduction and construction.Long-term aged binder. |
| Asphalt binders can have significantly different characteristics within the same grading category. | Grading is more precise and there is less overlap between grades. |
| Modified asphalt binders are not suited for these grading systems. | Tests and specifications are intended for asphalt “binders” to include both modified and unmodified asphalt cements. |
How to read a Performance Grade?
The PG grading system is based on climate, so the grade notation consists of two portions: high and low pavement service temperature. The major concern for high-temperature performance is rutting, which typically takes time to cumulate, therefore an average of 7-day maximum pavement temperature is used for describing the high-temperature climate. On the low-temperature side, thermal cracking can happen during the one really cold night; therefore the minimum pavement temperature is used for describing the low-temperature climate. For both high and low-temperature grades, PG grades are graded in a 6°C increment. The average 7-day maximum pavement temperature typically ranged from 46 to 82°C, and minimum pavement temperature typically ranged from −46°C to −10°C.
A binder identified as PG 64-10 must meet performance criteria at an average 7-day maximum pavement temperature of 64°C and also at a minimum pavement temperature of −10°C. Please note that maximum pavement temperature is typically higher than the air temperature by about 20°C since the dark color pavement absorbs the heat and retains it. The maximum pavement temperature is typically measured at about 1 inch below the pavement surface. However, the minimum pavement temperature occurs on the surface of the pavement and is equal to the air temperature.
The common minimum reliability used is 98%, so that means when the PG 64-10 binder is selected, the asphalt binder in the AC pavement should perform satisfactorily under normal traffic condition at the location where the extreme pavement temperature is within the range of −10°C and 64°C throughout its service life with a minimum 98% confidence level. Where the traffic condition is not typical, such as the really heavy traffic like an interstate highway, or slow traffic such as bus stop or intersection area, one or two grades stiffer asphalt binder may be used to help prevent the rutting problem.
Polymer modified binders are used wherever extra performance and durability are desired. Improvement in resistance to rutting, thermal cracking, fatigue damage, stripping, and temperature susceptibility have led polymer modified binders to be substituted for asphalt in many paving and maintenance applications. Especially when good rutting resistance for high temperature and good thermal cracking resistance for low temperatures are concurrently required in the same application, the polymer modification is generally required.
rule of thumb to differentiate the polymer modified binder from unmodified binder is to add both low and high-temperature grades together, if the sum is greater than 90, it is likely to be a polymer modified binder. For example, a Performance Grade bitumen 76-22 is likely to be a polymer modified binder since the sum is 98, while a Performance Grade Bitumen 64-10 is likely to be unmodified since the sum is 74.
PG Bitumen – Unmodified CHARACTERISTICS
| PG 46-34 | PG 46-28 | PG 52-28 | PG 58-28 | PG 58-22 | PG 64-22 | AASHTO Method | |
|---|---|---|---|---|---|---|---|
| Original Binder | |||||||
| Flash Point, COC,°C | 230 | T 48 | |||||
| Flash Point, P-M, °C | NS | ≥ 204 | ASTM D93 | ||||
| Rotational Viscosity @ 135°C, Pa·s | 3.00 | T 316 | |||||
| Dynamic Shear @ Grade Temperature,°C | 46 | 46 | 52 | 58 | 58 | 64 | T 315 |
| G*/sin @ 10 rad/sec, kPa | ≥ 1.00 | ||||||
| RTFOT Residue | |||||||
| Mass Loss, % | ≤ 1.00 | T 240 | |||||
| Dynamic Shear @ Grade Temperature,°C | 46 | 46 | 52 | 58 | 58 | 64 | T 315 |
| G*/sin @ 10 rad/sec, kPa | 2.20 | ||||||
| PAV Residue (Aging Temperature, °C) | 90 | 100 | R 28 | ||||
| Dynamic Shear @ Grade Temperature,°C | 10 | 13 | 16 | 19 | 22 | 25 | T 315 |
| G*/sin @ 10 rad/sec, kPa | 5000 | ||||||
| Creep Stiffness | -24 | -18 | -18 | -18 | -12 | -12 | |
| S, Mpa | ≤ 300 | T 313 | |||||
| m-value | ≥ 0.30 | T 313 |
Viscosity Grade Bitumen
Viscosity Grade Bitumen Description
Traditionally, paving bitumen have been specified in terms of their penetration, but the measurement of viscosity provides a more accurate method of specifying binder consistency and a more effective method of determining the temperature susceptibility of the bitumen. American Association of State Highway Officials (AASHTO) has two series of viscosity grade bitumen. One is denoted AC (asphalt cement), followed by a number indicating the viscosity in hundreds of poises at 60 C. The second series is denoted AR (aged residue) followed by a number indicating the viscosity in poises (not hundreds of poises) at 60 C after the bitumen has been aged.
In the early 1960s, an improved asphalt grading system was developed that incorporated a rational scientific viscosity test. This scientific test replaced the empirical penetration test as the key asphalt binder characterization. The viscosity grading system gave excellent performance results in the US for over twenty years. The viscosity grading system is more rational than the penetration grading system. Viscosity is defined as the inverse of fluidity. Viscosity thus defines the fluid property of the bituminous material. Viscosity is the general term for consistency and it is a measure of resistance to flow. Many researchers believe that grading of bitumen should be by an absolute viscosity in instead of the conventional penetration units. Viscosity grading is based on a fundamental, scientific viscosity test, which is conducted at 60˚C (near the maximum pavement temperature during summer) and its measurement unit is poise. The test equipment for measuring viscosity both at 60˚C and 135˚C.
Viscosity grading can be done on original (as-supplied) asphalt binder samples (called AC grading) or aged residue samples (called AR grading). The AC grading is based on absolute viscosity at 60 °C in units of 100 poises. Six asphalt cement viscosity grades were established as AC-2.5 (softest), AC-5, AC-10, AC-20, AC-30, AC-40 (hardest). AC-2.5 means asphalt cement with a target viscosity of 250 poises at 60˚C (250 has been abbreviated to 2.5). Similarly, AC-5, AC-10, AC-20, AC-30, and AC-40 mean asphalt cement with target viscosity of 500, 1000, 2000, 3000, and 4000 poises, respectively. Low viscosity grades AC-2.5 and AC-5 are used in cold climate while high viscosity grades AC-10 to AC-40 are generally suitable for the hot climate.
With AC grading, the asphalt binder is characterized by the properties it possesses before it undergoes the HMA manufacturing process. The AR grading system is an attempt to simulate asphalt binder properties after it undergoes a typical HMA manufacturing process and thus, it should be more representative of how asphalt binder behaves in HMA pavements. Table 1 lists key advantages and disadvantages of the viscosity grading system.
Viscosity grade bitumen have a thermoplastic property which causes the material to soften at high temperatures and to harden at lower temperatures. This unique temperature/ viscosity relationship is important when determining the performance parameters such as the adhesion, rheology, durability and application temperatures of bitumen. In the Viscosity Graded Bitumen specifications, further special emphasizes is placed on the Bitumen ductility.
Viscosity grading can be done on original (as-supplied) asphalt binder samples (called AC grading) or aged residue samples (called AR grading). The AR viscosity test is based on the viscosity of aged residue from the rolling thin film oven test. With AC grading, the asphalt binder is characterized by the properties it possesses before it undergoes the HMA manufacturing process. The AR grading system is an attempt to simulate asphalt binder properties after it undergoes a typical HMA manufacturing process and thus, it should be more representative of how asphalt binder behaves in HMA pavements. Table 1 lists key advantages and disadvantages of the viscosity grading system.
Advantages and Disadvantages of Viscosity Grading as stated below
| Advantages | Disadvantages |
|---|---|
| Unlike penetration depth, viscosity is a fundamental engineering parameter. | The principal grading (done at 25°C (77°F)) may not accurately reflect low-temperature asphalt binder rheology. |
| Test temperatures correlate well with:25°C (77°F) – average pavement temp.60°C (140°F) – high pavement temp.135°C (275°F) – HMA mixing temp. | When using the AC grading system, thin film oven test residue viscosities can vary greatly with the same AC grade. Therefore, although asphalt binders are of the same AC grade they may behave differently after construction. |
| Temperature susceptibility (the change in asphalt binder rheology with temperature) can be somewhat determined because viscosity is measured at three different temperatures (penetration only is measured at 25°C (77°F)). | The testing is more expensive and takes longer than the penetration test |
| Testing equipment and standards are widely available. |
| Standard | Grades Minimum of Absolute | Viscosity, Poise@ 600°C | Approximate penetration grade |
|---|---|---|---|
| IS73:2013 | VG 10 | 800 | 80-100 |
| IS73:2013 | VG 20 | 1600 | – |
| IS73:2013 | VG 30 | 2400 | 60-70 |
| IS73:2013 | VG 40 | 3200 | 30-40/40-50 |
Viscosity Grade Bitumen Specification (ASTM D3381-09)
| Property | Units | AC-10 | AC-20 | AC-30 | AC-40 | Test Methods |
|---|---|---|---|---|---|---|
| Viscosity, 140°F (60°C) | P | 1000±200 | 2000±400 | 3000±600 | 4000±800 | ASTM D-2171 |
| Viscosity, 275°F (135°C), Min | cSt | 150 | 210 | 250 | 300 | ASTM D-2171 |
| Penetration, 77°F (25°C), 100g, 5sec, Min | 0.1MM | 70 | 40 | 30 | 20 | ASTM D-5 |
| Flash point, Cleveland open cup, Min | °C | 219 | 232 | 232 | 232 | ASTM D-92 |
| Solubility in trichloroethylene, Min | %Wt | 99 | 99 | 99 | 99 | ASTM D-2042 |
| Tests on residue from thin-film oven test: | ||||||
| – Viscosity, 140°F (60°C), Max | P | 5,000 | 10,000 | 15,000 | 20,000 | ASTM D-2171 |
| – Ductility, 77°F (25°C), 5cm/min, Min | CM | 50 | 20 | 15 | 10 | ASTM D-113 |
Viscosity Grade Bitumen Specification (IS 73:2013)
| Property | Units | VG-10 | VG-20 | VG-30 | VG-40 | Test Methods |
|---|---|---|---|---|---|---|
| Penetration at 25°C, 100g, 5sec, Min | 0.1MM | 80 | 60 | 45 | 35 | IS 1203 |
| Absolute viscosity at 60°C | P | 800-1200 | 1600-2400 | 2400-3600 | 3200-4800 | IS 1206 (Part 2) |
| Kinematic viscosity at 135°C, Min | cSt | 250 | 300 | 350 | 400 | IS 1206 (Part 3) |
| Flash point (Cleveland open cup), Min | °C | 220 | 220 | 220 | 220 | IS 1448 [P : 69] |
| Solubility in trichloroethylene, Min | %Wt | 99 | 99 | 99 | 99 | IS 1216 |
| Softening point (R&B), Min | °C | 40 | 45 | 47 | 50 | IS 1205 |
| Tests on residue from thin film oven test: | ||||||
| – Viscosity ratio at 60°C, Max | 4 | 4 | 4 | 4 | IS 1206 (Part 2) | |
| – Ductility at 25°C, Min | CM | 75 | 50 | 40 | 25 | IS 1208 |
Penetration Grade Bitumen
Penetration Grade Bitumen Description
Pentration / Paving Grade Bitumen is Bitumen classified using the penetration property. Penetration grading’s basic assumption is that the less viscous the asphalt, the deeper the needle will penetrate. Bitumen which is produced during the process of oxidation of vacuum bottom (the Bitumen production feedstock that derives from distillation tower residue in vacuum oil refineries) at bitumen production unit in a manner that its penetration point (kind of test to indicate the hardness of bitumen) in specified group is classified in different grade of Bitumen.
The penetration grading system was developed in the early 1900s to characterize the consistency of semi-solid asphalts. Penetration grading quantifies the following asphalt concrete characteristics:
Penetration Grade Bitumen or Paving Bitumen is commonly used in road surfacing, and some industrial applications. Additional processing yields other grades of bitumen products and their application.
Advantages of Penetration / Paving Grade bitumen
The test is done at 25° C (77° F), which is reasonably close to a typical pavement average temperature.
May also provide a better correlation with low-temperature asphalt binder properties than the viscosity test, which is performed at 60° C (140° F).
Temperature susceptibility (the change in asphalt binder rheology with temperature) can be determined by conducting the test at temperatures other than 25° C (77° F).
The test is quick and inexpensive. Therefore, it can easily be used in the field.
| Advantages | Disadvantages |
|---|---|
| The test is done at 25° C (77° F), which is reasonably close to a typical pavement average temperature. | The test is empirical and does not measure any fundamental engineering parameter such as viscosity. |
| May also provide a better correlation with low-temperature asphalt binder properties than the viscosity test, which is performed at 60° C (140° F). | Shear rate is variable and high during the test. Since asphalt binders typically behave as a non-Newtonian fluid at 25° C (77° F), this will affect test results. |
| Temperature susceptibility (the change in asphalt binder rheology with temperature) can be determined by conducting the test at temperatures other than 25° C (77° F). | Temperature susceptibility (the change in asphalt binder rheology with temperature) cannot be determined by a single test at 25° C (77° F). |
| The test is quick and inexpensive. Therefore, it can easily be used in the field. | The test does not provide information with which to establish mixing and compaction temperatures. |
Penetration Grade Bitumen Specification (AASHTO M 20 and ASTM D 946)
| Units | 40/50 | 60/70 | 80/100 | 100/120 | Test Methods | |
|---|---|---|---|---|---|---|
| Specific Gravity @25°C | – | 1.01-1.06 | 1.01-1.06 | 1.01-1.05 | 1.01-1.04 | ASTM D-70 |
| Penetration @25°C, 100gm, 5sec | 0.1MM | 40-50 | 60-70 | 80-100 | 100-120 | ASTM D-5 |
| Softening Point, Ring & Ball | °C | 52-60 | 49-56 | 45-52 | 42-49 | ASTM D-36 |
| Ductility @25°C, after TFOT, Min | CM | 100 | 100 | 100 | 100 | ASTM D-113 |
| Loss on Heating, Max | %Wt | 0.2 | 0.2 | 0.5 | 0.5 | ASTM D-6 |
| Drop in Penetration after Heating, Max | % | 20.0 | 20.0 | 20.0 | 20.0 | ASTM D-6 & D-5 |
| Flash Point Cleveland open cup, Min | °C | 250.0 | 250.0 | 232.0 | 250.0 | ASTM D-92 |
| Solubility in CS2, Min | %Wt | 99.5 | 99.5 | 99.5 | 99.5 | ASTM D-4 |
| Organic Matter Insoluble in CS2, Max | %Wt | 0.5 | 0.5 | 0.5 | 0.5 | ASTM D-4 |
| Sport Test | – | Negative | Negative | Negative | Negative | *A.A.S.H.O.T.102 |
Bitumen Specification European Standard (BS EN 12591)
| Units | 35-50 | 40-60 | 50-70 | 70-100 | 100-150 | Test Methods | |
|---|---|---|---|---|---|---|---|
| Penetration @25°C, 100gm, 5sec | 0.1MM | 35-50 | 40-60 | 50-70 | 70-100 | 100-150 | EN 1426 |
| Softening Point, Ring & Ball | °C | 50-58 | 48-56 | 46-54 | 43-51 | 39-47 | EN 1427 |
| Resistace to Hardening@163°C | |||||||
| – Change in mass, Max | %Wt | 0.5 | 0.5 | 0.5 | 0.8 | 0.8 | EN 12607-1 |
| – Retained Penetration, Min | 0.1MM | 53 | 50 | 50 | 46 | 43 | |
| – Softening point after hardinging, Min | °C | 52 | 49 | 48 | 45 | 41 | |
| Other Properties | |||||||
| Flash Point Cleveland open cup, Min | °C | 240 | 230 | 230 | 230 | 230 | EN ISO 2592 |
| Solubility in CS2, Min | %Wt | 99.0 | 99.0 | 99.0 | 99.0 | 99.0 | EN 12592 |
| Kinematic Viscocity @135°C, Min | mm2/S | 370 | 325 | 295 | 230 | 175 | EN 12595 |
Safety information
Bitumen have been usually flammable and may be kept away from fire or flame.
Carbon dioxide should be used as a fire suppressant.
Engineers or workers who work with bitumen ought to use leather gloves, safety eyeglasses and proper clothes and boots when they are operating with hot bitumen.
The temperature of hot bitumen is around 300 F and it’ll result in severe skin burns and eye injury.
HJ Oil Group supplies all Penetration Graded Bitumen Grades in correspondence to ASTM D946-09 and EN 12591-2009.
ASTM D946-09 Grades:
Bitumen 10/20
Bitumen 30/40
Bitumen 40/50
Bitumen 60/70
Bitumen 85/100
Bitumen 120/150
Bitumen 200/300
EN 12591-2009 Grades:
Bitumen 20/30
Bitumen Penetration Grade 30/45
Bitumen Penetration Grade 35/50
Bitumen Penetration Grade 40/60
Bitumen Penetration Grade 50/70
Bitumen Penetration Grade 70/100
Bitumen Penetration Grade 100/150
Bitumen Penetration Grade 160/220
Bitumen Emulsion
Bitumen Emulsion Description
Bitumen emulsion is a mixture of water & asphaltum. Hey wait, we know that bitumen is a oil product and it cannot be mixed with water. That is why we add an emulsifier (a surface active agent) with water before adding bitumen. Addition of emulsifier with water facilitates breaking of asphaltum into minute particles and keeps it dispersed in suspension.Therefore we can say that bitumen emulsions are a liquid product consisting of three things, (i.e. water + Emulsion + Asphaltum) where droplets of Asphaltum are suspended in water.
Bitumen emulsions are usually dispersions of minute droplets of bitumen in water and are examples of oil-in-water emulsions.
The bitumen content can be varied to suit different requirements and is typically between 30% and 70%. The primary objective of emulsifying bitumen is to obtain a product that can be used without the heating normally required when using cutbacks and paving grade bitumen. In the manufacture of bitumen emulsions, hot bitumen is sheared rapidly in water containing an emulsifying chemical (emulsifier). This produces very small particles of bitumen (the dispersed phase) dispersed in water (the continuous phase). The bitumen particles are stabilised in suspension and do not readily coalesce due to the presence of the emulsifier, which is concentrated on the surface of the bitumen particles. During application, the water in a bitumen emulsion is either lost by evaporation, or it may separate from the asphalt because of the chemical nature of the surface to which the emulsion is applied. This process is referred to as breaking. Because Asphaltum has a density only slightly higher than water, sedimentation of the Asphaltum droplets in an emulsion during storage is very slow. Emulsions can usually be regenerated after long storage times by gentle stirring to redisperse the bitumen droplets.
Composition and Different Types of Bitumen Emulsion
The bitumen emulsion is classified into two types:
1- Based on Setting Time
When the bitumen emulsion is applied on the aggregate for the road works the water evaporates leaving behind the asphalt droplets. These droplets spread on the aggregate and bind with each other and gains strength eventually.
Based upon the time taken by the vitamin emulsion to evaporate the water and between particles to separate from water, bitumen emulsion is further classified into 3 types based on setting time:
a) Slow setting emulsion
In this type of emulsion, a special type of emulsifier is used to slow the process of water evaporation. This type of emulsifier are relatively stable.
b) Medium setting emulsion
This type of bitumen emulsion doesn’t break as when applied on aggregate. The process of evaporation starts when the fine dust of mineral are mixed with the aggregate emulsion mix.
c) Rapid setting emulsion
This type of bitumen emulsion breaks down rapidly as it comes with contact with aggregate helping in fast setting and rapid curing.
2- Based on Surface Charge
Bitumen emulsion is a combination of water and asphalt. As the mixture of water and oily products quickly separate, a third component is normally added to the mixture, in order to make it more stable.
Known as an emulsifier, this third component is used for making a mixture of water and oil dispersed in each other. In addition to their ability to reduce the tension between oil and water molecules, emulsifiers have an electronic charge that affects the molecules of emulsion and lead to the categorization of it into Cationic and Anionic.
– Anionic Bitumen Emulsion
– Cationic Bitumen Emulsion
In anionic bitumen emulsion, the tiny droplets of bitumen are electronegatively recharged. In Cationic bitumen emulsion, the tiny droplets of bitumen are electro positively charged.
The average and commonly used emulsions is cationic between emulsions. Selection of positive or negative recharge between emulsions depends upon the mineral composition of aggregate on which it is used
Ex: In the case of silica-rich aggregates the surface of silica is aggregate is positively charged therefore cationic bitumen emulsion is used which helps in better spreading and binding of bitumen with aggregates.
The electronic charge of BE decides on what kind of surface it should be used. Some aggregates (such as marble aggregates) mix better with anionic bitumen emulsion and some others are a better solution to cationic bitumen emulsion (such as granite aggregates).
Both cationic and anionic bitumen emulsions are categorized according to the setting time. Look at the table below to find the various categories of bitumen emulsion and their globally standard names.
Bitumen Emulsion Applications
Emulsion Bitumens primarily used for tack coats for use in between hot mix asphalt layers and prime coats for thin hot mix surfacing layers or a chip seal pavements. Each application places particular demands on the emulsion. There is a considerable amount of variation between countries on the choice of emulsion for each application, but the table summarizes the most common practice. Anionic emulsions are hardly used outside North America for road construction but may be used for some industrial coatings.
– It can be used in damp environment on wet aggregates
– Road repair work can be carried out in minimum time
– Provides better tack coat with better workable conditions
– It can be used in any season
– Since heating is not required it can’t pollute air
– Long storage stability in clean containers/Tanks
Advantages and Uses of Bitumen Emulsions are:
- used extensively in bituminous road construction. Other than this they are used for maintenance and repair work.
- Emulsions can be used in wet weather even if it is raining.
- it Is ecofriendly as it is water based.
- used in soil stabilization in desert areas.
- It doesn’t need extra heat while placing.
- There is no wastage in placing and laying of bitumen.
- They possess anti-stripping properties.
- Rapid setting type of emulsion are used in surface of roads.
- Medium setting type of emulsion are used in premixing of bitumen and coarse aggregate.
- Slow setting type of emulsion are used with fine aggregates as the surface area is large and requires time for uniform mixing.
Cutback Bitumen
Cutback Bitumen Description
Cutback Bitumen ( Liquid Bitumen ) is Bitumen that is dissolved in a solvent. Typical solvents include Naphtha, gasoline and kerosene, white spirit etc. The type of solvent controls the curing time while the amount determines the viscosity of the Liquid Bitumen. Bitumen is ‘cutback’ by adding controlled amounts of petroleum distillates such as kerosene. This is done to reduce the viscosity of the bitumen temporarily so it can penetrate pavements more effectively or to allow spraying at temperatures that are too cold for successful sprayed sealing with neat bitumen. The materials used to cutback bitumen will evaporate after application to leave the remaining material similar in hardness to the original bitumen.
Cutback bitumen is a range of binders that are produced by blending (mixing) penetration grade bitumen and a hydrocarbon solvent, such as paraffin or mineral turpentine.
When the solvent has evaporated, the binder returns to its original penetration grade to tie the particles together. Cutback bitumen gets its name from the solvent that is involved in the process, because the solvent “cuts back” or evaporates, leaving behind the binder to “get on with the job”. The solvent used in cutback bitumen is called the “cutter” or “flux”.
Three types of solvents are used for the blending process: slow-curing, medium-curing or rapid-curing solvents. The latter two are the most common in South Africa. The choice of the solvent determines the rate at which the bitumen will cure when exposed to air. A rapid-curing (RC) solvent will evaporate faster than a medium-curing (MC) solvent. Curing relates to the evaporation rate of the solvent which influences the setting time of the bitumen. The viscosity of the cutback bitumen is determined by the proportion of solvent added: the higher the proportion of solvent, the lower the viscosity of the cutback.
Cutbacks differ from penetration grade bitumen in that they are more workable — in other words, they can be more easily reshaped. Less heat is required to liquefy cutback bitumen than penetration bitumen, making it easier to use at lower temperatures.
Typical cutback bitumens are MC 30 and RC 250. The letters in the name refer to the curing action of the solvent, and the number to the viscosity of the binder.
Cutback bitumen is classified based on viscosity grade. It is divided into three categories:
1- Rapid-Curing (RC) :The cutback bitumen is known as rapid-curing (RC) if the bitumen is solved in gasoline. The reason is that evaporation occurs quickly and the bitumen is deposited.
2- Medium-Curing (MC) :MC cutbacks are prepared by solving bitumen in kerosene which evaporates more slowly than gasoline.
3- Slow-Curing (SC) :Slow-curing cutback may be achieved from solving bitumen in gasoil or fuel oil or directly from distillation of crude oil.
Application of Cutback Bitumen
Cutback bitumens suitable for primer sealing can also be used in the manufacture of pre-mix asphalt, which is used in patch repairs. Cutback bitumens are used extensively in sprayed sealing applications, particularly in cooler weather where they provide improved initial stone retention due to their lower viscosity. Typically, a single application of the appropriate cutback bitumen is sprayed onto the primed pavement onto which aggregate is laid.
Prime and Tack Coating
The process of priming involves applying a low viscosity binder to a prepared but usually unbound aggregate base. It is intended to be absorbed by the top layers of the base and provide a surface more easily ‘wetted’ by a subsequent bituminous covering. The primer will be able to carry traffic for a short time (although this practice is uncommon) and help control dust. Generally, primers are applied at rates between 0.5 and 1.4 L/m2. Cutback bitumens suitable for priming are also used for tack coats, which are applied to an underlying surface to help with the adhesion of subsequent asphalt layer. A typical application rate is between 0.2 and 0.4 L/m2.
Prime Sealing
Where temperatures are too cool for an effective priming operation, or where traffic is likely to upset a primed surface before the final seal can be sprayed, a primer seal can be used to give adequate protection of the pavement for periods of up to 6 to 12 months. Cutback bitumens suitable for primer sealing can also be used in the manufacture of pre-mix asphalt, which is used in patch repairs.
Spray Sealing
Cutback bitumens are used extensively in sprayed sealing applications, particularly in cooler weather where they provide improved initial stone retention due to their lower viscosity. Typically, a single application of the appropriate cutback bitumen is sprayed onto the primed pavement onto which aggregate is laid.
HJ Oil GRUOP supplies and provides transfer of technology for production of all cutback Bitumens in correspondence to ASTM D2026, D2027, D2028, AASHTO M82-75 (2008), AASHTO M92-92 (2008). For any inquiries, please contact our sales team on info@www.hjoilgroup.com
- Slow Curing Cutbacks (ASTM D2026)
- Medium Curing Cutbacks (ASTM D2027 or AASHTO M82-75 2008)
- Rapid Curing Cutbacks (ASTM D2028 or AASHTO M81-92 2008)
USES OF CUTBACK & EMULSION BITUMEN IN DIFFERENT SYSTEMS OF ROAD MAINTENANCE
| System | Description & Uses | Recomende Product |
| SurfaceDressing | An application of binder on the road surface by a bitumen distributor followed by a covering of aggregates/chippings spread by a hopper gritter. Can be a single or double-layer surface dressing | Cutback: MC -3000 |
| Prime Coating | An application of binder on a granular base to prepare for an asphalt surfacing .Normally a slow setting emulsion or cutback is used for better penetration purposes to seal off the road base. The rate of application can vary from 0.4-1.4 liter/m2 | Cutback : MC-30 MC -70 |
| Tack Coating | A very light application of binder –hand or machine sprayed –to ensure bonding between the existing layer and the new overlay. The rate of application is normally between 0.25-0.7 liter/m2, depending on the surface being sprayed | Emulsion: K1-40 : RS-1K: RS-2K |
| Semi– Grouting /Penetration Macadam | An application of hot binder on a compacted layer of coarse aggregate | Emulsion : RS-3K : MC-3000 Other : Bitumen |
| Slurry Sealing | A maintenance technique where specially tailored emulsion, aggregates, water, and /or mineral filler is mixed in an on-site distributor and spread on an existing road surface at a thickness of 3-6 mm. It is both a preventive and corrective maintenance method for sealing of surface cracks, waterproofing asphalt surfaces and stopping oxidation | Emulsion: ALFA/SS |
| Fog Sealing /Mist Spraying | It is similar to tack coating in that is a very light application of diluted emulsion for renewal/rejuvenation of old asphalt surfaces. The emulsion is usually diluted to a concentration of about 25-30% binder and applied at a rate of 0.3-0.8 liter/m2 | Emulsion : K1-40 : SS-1K : ALFA |
| Dust Binding | A light application of 0.5-2.0 liter/m2 using diluted bitumen emulsion for dust control on unpaved roads | Emulsion: K1-40: SS-1K |
Oxidized Bitumen
Oxidized Bitumen Description
Blown bitumen grade or Oxidized Bitumen are produced by passing air through the penetration grades. This process gives the bitumen more rubbery properties than its original formula and they are simply harder bitumen. Hard bitumen under controlled temperature conditions is widely used as an anti-slip layer compound in the piling industry, for manufacture of roofing felts, the roofing and waterproofing industries, for sound dampening felts and under carriage sealant in the automotive industry, electric cable joint protection, joint filling compound, sealant compound and many others. Also used in sealing saw cuts and joints where expected movements are minimum. It is also used in the manufacturing of bituminous marine mastic for the oil & gas pipeline joints.
The most popular grades are; 95/25, 85/35, 90/40 and 115/15. We are also capable of producing other grades of Blown Bitumen upon request by our customers. Blown Bitumen high softening temperatures qualify them as excellent sealant for prevention from bleeding in high temperature applications. Blown Grade Bitumen shall be broken up into small pieces (for blown grade in molded cake form) and heated slowly to the application temperature of 220ºC to 230ºC. blown Bitumen is predominantly used in the piling industry as an anti slip compound for the manufacture of under carriage sealants in the automobile industry. It is also used as a sealant compound, as a joint filling compound apart from being used in the manufacture of roofing felts and sound dampening felts. Further, Blown Bitumen is used in the manufacture of bituminous marine mastic, which is required for the oil and gas pipeline joints. blown Bitumen is available in different grades like 95/25, 85/25, 75/25, 90/40 and 115/15. Tavoil is also capable of producing other grades of Oxidized Bitumen according to the specifications of individual clients.
Oxidized Bitumen Characteristics
Some of the major advantages of Oxidized Bitumen are that it is completely water resistant, highly flexible and durable. Further, it is chemically very stable. blown bitumen is a very flexible compound that is not only chemically stable but also a very durable compound apart from being completely water resistant. Lastly, Blown Bitumen has some very prominent technical advantages that makes it a very sought after compound in various applications.
Blown Bitumen Applications
Oxidized bitumens are used almost entirely for industrial applications, eg roofing, flooring mastics, pipe coatings, paints, etc, and are specified and designated by both softening point and penetration tests.
• Used As a bonding bitumen for roofing sheet membranes.
• Used As a hot-applied waterproofing layer.
• Used in Carpet tile manufacture.
• Used As a raw material for liquid bitumen coatings.
• Used in production of bituminous paint, mastic.
• Used in rust proof pipe coatings.
• Used as an anti-slip layer compound in the piling industry.
• Used in production of roofing and sound dampening felts.
• Used as under carriage sealant in the automobile industry, electric cable joint protection, joint filling compound, sealant compound and much more in our day to day life.
We are also capable of producing other grades of Blown Bitumen upon request by our customers. Oxidized Bitumen high softening temperatures qualify them as the excellent sealant for prevention from bleeding in high-temperature applications. Blown Grade Bitumen shall be broken up into small pieces (for the blown grade in molded cake form) and heated slowly to the application temperature of 220ºC to 230ºC. Oxidized Bitumen is predominantly used in the piling industry as an anti-slip compound for the manufacture of undercarriage sealants in the automobile industry. It is also used as a sealant compound, as a joint filling compound apart from being used in the manufacture of roofing felts and sound dampening felts. Further, Oxidized Bitumen is used in the manufacture of bituminous marine mastic, which is required for the oil and gas pipeline joints. This Oxidized Bitumen is available in different grades like 95/25, 85/25, 75/25, 90/40 and 115/15. Oxidized is also capable of producing other grades of Oxidized Bitumen according to the specifications of individual clients
Oxidized Bitumen Grades are suitable for sealing saw cuts and joints where there is expected to be the minimum amount of moving in the joint. Their wide temperature range prevents bleeding in high-temperature applications. Oxidized bitumen can also be used in industrial applications like roofing, flooring, mastics, pipe coatings, electrical applications to name a few.
Oxidised bitumen ” Oxidized Bitumen, Oxidized Asphalt ” range is used in the waterproofing industries, for carpet-backing, corrosion protection, acoustic panels and the manufacture of paints, amongst other applications.
Air-blowing: The manufacturing process used to make oxidized roofing asphalts in which air is blown through an asphalt flux. An exothermic oxidation reaction occurs, yielding an asphalt that is harder, more viscous, less volatile, and less temperature-susceptible than the asphalt flux used as the feedstock to the process.
Asphalt, oxidized (blown or air-refined) (CAS number 64742–93–4): Asphalt treated by blowing air through it at elevated temperatures to produce physical properties required for the industrial use of the final product. Oxidized asphalts are used in roofing operations, pipe coating, undersealing for Portland cement concrete pavements, hydraulic applications, membrane envelopes, some paving-grade mixes [AI 1990b], and the manufacture of paints [Speight 1992].
Blowing still: A closed-process vessel fitted at its base with a sparger and used in the air-blowing process to make many types of roofing asphalt.
Coating asphalt: An air-blown or oxidized asphalt used to manufacture roofing materials used in a variety of roofing systems such as asphalt shingles, polymer-modified bitumen roofing, reinforcing and underlayment felts, and roll roofing products.
Modified bitumen: A roofing system based on membranes manufactured by impregnating or coating one or more fabric plies with a straight-run or oxidized asphalt modified using a polymer, usually atactic polypropylene (APP) or styrene-butadiene-styrene (SBS). Modified bitumen systems may be torch-applied or installed by adhesion in hot asphalt or a cold-applied, solvent-based asphalt adhesive (cutback asphalt). Modified bitumen systems are used on low-slope (primarily commercial or industrial) roofs.
Bitumen
Bitumen Definition
Bitumen, also known as asphalt in the United States, is a substance that forms through the distillation of crude oil. It has waterproofing and adhesive properties. Bitumen production through distillation removes lighter crude oil components, such as gasoline and diesel, leaving the “heavier” Asphalt behind. The producer often refines it several times to improve its grade. Bitumen can also occur in nature: Deposits of naturally occurring bitumen form at the bottom of ancient lakes, where prehistoric organisms have since decayed and have been subjected to heat and pressure.
Bitumen is viscous, nonvolatile liquid or solid. Asphalt is a complex colloid system the chemical properties of which are dependent on the properties of crude oil from which it is produced. Pure bitumen is a colloid dispersion of microscopic asphalt particles (dispersion phase). The chemical composition of Asphalt is a mixture of various hydrocarbons with molecules of oxygen, sulfur, and nitrogen. Hydrocarbons present in bitumen are mostly condensed naphthene and aromatic rings with the small number of side paraffin chains. Mass fraction of hydrocarbons is 75-85%, hydrogen 9-10%, oxygen 2-8%, sulphur 5-7%, and nitrogen 0.1-0.5%. Bitumen is partially or completely soluble in various organic solvents. Dissolved fractions of Asphalt insolvent are called maltenes or petrolenes, and undissolved fractions are called asphaltenes. The maltenes are a mixture of resins and oil, and they are a dispersing agent. For the most part, the physical properties of bitumen depend on the dispersion degree of asphaltenes in maltenes.
Properties of Asphalt
– Adhesion: Bitumen has the ability to adhere to a solid surface in a fluid state depending on the nature of the surface. The presence of water on the surface will prevent adhesion.
– Resistance to Water: Bitumen is water-resistant. Under some conditions, water may be absorbed by minute quantities of inorganic salts in the bitumen or filler in it.
– Hardness: To measure the hardness of bitumen, the penetration test is conducted, which measures the depth of penetration in tenths of mm. of a weighted needle in bitumen after a given time, at a known temperature. Commonly a weight of 100 gm is applied for 5 sec at a temperature of 77 °F. The penetration is a measure of hardness. Typical results are 10 for hard coating asphalt, 15 to 40 for roofing asphalt and up to 100 or more for waterproofing bitumen.
– Viscosity and Flow: The viscous or flow properties of bitumen are of importance both at high temperature during processing and application and at low temperature to which bitumen is subjected during service. The flow properties of bitumen vary considerably with temperature and stress conditions. Deterioration, or loss of the desirable properties of bitumen, takes the form of hardening. Resultantly, a decrease in adhesive and flow properties and an increase in the softening point temperature and coefficient of thermal expansion.
– Softening point: Softening point is the temperature at which a steel ball falls a known distance through the bitumen when the test assembly is heated at a known rate. Usually, the test consist of a (3/8)in dia steel ball, weigh 3.5 gm, which is allowed to sink through a (5/8) in dia, (1/4) in the thick disk of bitumen in a brass ring. The whole assembly is heated at a rate of 9 °F per min. Typical values would be 240 °F for coating grade asphalts, 140 °F to 220 °F for roofing asphalt and down to 115 °F for bituminous waterproofing material.
– Ductility: The ductility test is conducted to determine the amount bitumen will stretch at a temperature below its softening point. A briquette having a cross-sectional area of 1 in2 is placed in a tester at 77 °F. Ductility values range from 0 to over 150 depending on the type of bitumen.
Bitumen Applications
The major bitumen produced in Middle East and the world known as Asphaltum is used in road construction. In road construction, It is used as a bonding agent for asphalt, and the use of it in the construction industry is ranked second as insulation. Estimates show that the annual amount of Egyptian bitumen in the world is about 102 million tons. Of this, about 85 percent of the Asphaltum is used in the road construction industry, and the 60/70 bitumen is most used. More than 10% of the bitumen produced in the world is used in the building industry and as insulation. And seagulls are used as sealing, insulating, pipe coating, etc.
- Surface coating
- Intruding Macadam
- Cold machine mixes
- Suspended seals
- Surface lining
- Lining reinforcement consolidation of soil-in-situ
- Dust Controlling
- Oil mulch
- Highways
- Airport runways
- Footways / Pedestrian Ways
- Car parks
- Racetracks
- Tennis courts
- Roofing
- Damp proofing
- Dams
- Reservoir and pool linings
- Soundproofing
- Pipe coatings
- Cable Coatings
- Paints
- Building Water Proofing
- Tile underlying waterproofing
- Newspaper Ink Production
- And many other applications
Pipe Coating
Coating systems advanced and at the same time modified polymers on the basis of economic the result is a wide research and long-lasting oil companies shell and Phoenix are Denmark. the characteristics of the coating causing severe epidemics can be high adhesion and resistant top of that soil degradation and stresses cathodic. Has your unique restorative properties. An article for corrosion protection of steel pipes buried in soil for a long period of time, with an appropriate yield. This coating due to being economical and safe for the environment continues to be an option in the transmission lines projects.
Bituseal Coating System
The Bituseal Coating system which was jointly developed by Phoenix International A/S and Shell International Petroleum Co.
bituseal is a PMB pipe coating system which combines the ease of hot applied coating processes with a high degree of corrosion protection and offers both reliability and affordability to clients. In terms of its technical properties, Bituseal matches and even outperforms 3-layer polyethylene coating.Bituseal has an excellent record in gas, water, and offshore pipelines.
Bituseal Coating Field Joint Membrane
Joints are the weakest link in any pipeline. The Bituseal Field Joint Membrane is specifically designed for fast, easy application on-site and to afford the same level of corrosion protection both in pipelines and joints. Bituseal Membrane is to cover pipeline joints or repairing damaged sections of coatings. It can be supplied either in the form of rolls or patches. It is a unique form of cover from both technical and economical viewpoints and a superb substitute for heat shrinkable sleeve. Apart from Bituseal system, it is also applicable on several other coatings like 3-layer polyethylene, bitumen enamel and coal tar with great consistency.
Roll Sheet
WaterProofing Bitumen Membrane Sheet (Here referred to as WPBS) are the best industrial outcome in the area of waterproofing ever attained by scientific and technological advancement. These products enable us to prevent the adverse effects of rain and snow water penetration into structures from their foundation up to roof. Employing different polymers and synthetic fibers, WPBS pass through well-equipped labs to be amended for attaining resistance against, high and low temperatures, tearing tension, and penetration of water
In addition to low weight and resistance against cold, heat, expansion and contraction, HJ OIL WPBS show high endurance being produced in two aluminum-covered and polyethylene film-covered versions. There two types of base products: single layered (nonwoven Spunbond polyester), and double layered (stringed fiber gloss tissue and 110 gr polyester) giving the product higher tensile strength against vibrations of the structure. WPBS is used in waterproofing of roofs, water canals, the foundation of tunnels, dams, pools, sloped surfaces, and the like.
Also, HJ OIL Bitumen membrane sheet reinforced by two layers of fiberglass and non-woven tissues with “needdle type” polyester. Azargum humidity polyester in spite of economic point of view possesses perfect utility qualities, therefore, resolves additional directional stability and ordinary surface replacements.
Types of Bitumen By Grade
There are different types of asphalt cement available with different properties, specifications and uses based on requirements of consuming industry.
Oxidized Grade
Blown bitumen grades or Oxidized Bitumen are produced by passing air through the penetration grades. This process gives the bitumen more rubbery properties than its original formula and they are simply harder bitumen. Hard asphalt under controlled temperature conditions is widely used as an anti-slip layer compound in the piling industry, for manufacture of roofing felts, the roofing and waterproofing industries, for sound dampening felts and under carriage sealant in the automotive industry, electric cable joint protection, joint filling compound, sealant compound and many others. Also used in sealing saw cuts and joints where expected movements are minimum. It is also used in the manufacturing of bituminous marine mastic for the oil & gas pipeline joints.
Penetration Grade
Graded Bitumen is classified by the depth to which a standard needle will penetrate under specified test conditions. This “pen” test classification is used to indicate the hardness of bitumen, lower penetration indicating a harder bitumen. Specifications for penetration graded bitumens normally state the penetration range for a grade, e.g. 50/70. Other tests are used to classify the bitumen for specification purposes, such as softening point, solubility, flash point etc.
Performance Grade
Performance Grade (PG) bitumen is Asphaltum which is graded based on its performance at different temperatures. The Long-Term Pavement Performance(LTPP) has given certain algorithm to calculate the temperature of the pavement based on the temperature of the air above. From this, the highest and the lowest temperatures of the pavement is calculated and the bitumen that performs well in that temperature range is selected.
Viscosity Grade
Viscosity Grade Bitumen (Asphalt) is a standard grade Asphaltum usually used as a Paving Grade Bitumen suitable for road construction and for the production of asphalt pavements with superior properties. This grade of Asphaltum is mainly used in the manufacture of hot mix asphalt for bases and wearing courses, and possesses characteristics and qualities unique sand quite different from other agents. They achieve very flexible and tenacious connections with other materials due mainly to viscoelastic response of Asphaltum, which behaviour depends on how fast charges are applied.
Polymer Modified
Polymer modified bitumen (PMB) is one of the specially designed and engineered Asphaltum grades that are used in making pavement, roads for heavy duty traffic and home roofing solutions to withstand extreme weather conditions. PMB is a normal bitumen with the added polymer, which gives it extra strength, high cohesiveness and resistance to fatigue, stripping and deformations, making it a favorable material for infrastructure.
Other Types of Bitumen
Cutback Bitumen
Cutback or Liquid Bitumen is asphaltum that is dissolved in a solvent. Typical solvents include Naphtha, gasoline and kerosene, white spirit etc. The type of solvent controls the curing time while the amount determines the viscosity of the Cutback Bitumen. Bitumen is ‘cutback’ by adding controlled amounts of petroleum distillates such as kerosene. This is done to reduce the viscosity of the asphaltum temporarily so it can penetrate pavements more effectively or to allow spraying at temperatures that are too cold for successful sprayed sealing with neat Asphaltum. The materials used to cutback bitumen will evaporate after application to leave the remaining material similar in hardness to the original asphaltum.
Blown Bitumen
It comes from hot air blown to pure asphaltum in the last stage of refining. In this process, hot air having 200-300 degree centigrade temperature is blown to bitumen container with porous tubes. In this process, hydrogen atoms in Asphaltum hydrocarbon are combined with oxygen in the air and by forming water, polymerization happens. Compared with pure Asphaltum, blown asphalt has a low penetration rate and a high softness point. This kind is used in making roof sheets, automobile battery, and coating.
Natural Bitumen
Natural bitumen or native asphalts are a class of Asphaltum which have been naturally produced due to climate conditions in the course of time, and are used without the need to be processed in distillation ways; they are very varied regarding their composition and properties.
Coating Bitumen
Bitumen coating compositions having substantially improved application and drying properties and producing coatings of improved properties including resistance to ultraviolet rays and alligatoring resulting therefrom said coating compositions comprising volatile solvent solutions of a bitumen coating material having softening point between 110 F To 250 F. The bitumen coating are also characteristically non-viscous materials which are not thixotropic and are therefore ordinarily applied as thin films. It’s compositions may also contain filler materials which tend to settle from the non-thixotropic compositions after storage for only a short time. It has been proposed in the past to add inert colloidal fillers such as silica to obtain thixotropic properties and thicker films on the application of the compositions. However, even such inert fillers tend to affect only solution properties and generally exist in the finished coating as an expensive additive which does not benefit other properties of the coating.
Bitumen Emulsion
This is a mixture of water & asphaltum. Hey wait, we know that asphaltum is a oil product and it cannot be mixed with water. That is why we add an emulsifier (a surface active agent) with water before adding asphaltum. Addition of emulsifier with water facilitates breaking of asphaltum into minute particles and keeps it dispersed in suspension.Therefore we can say that a bitumen emulsion is a liquid product consisting of three things, (i.e. water + Emulsion + Asphaltum) where droplets of asphaltum are suspended in water.