Bitumen test methods

Penetrability is the depth, expressed in tenths of a millimeter, a standard steel needle penetrates into a bitumen sample at 25°C. The needle carries a weight of 100 g and the test is applied for five seconds. The corresponding test method is relatively difficult to carry out and is defined in France by the standard NF T 66-004, and in the USA by the method ASTM D 583. Penetration is related to the viscosity. 

Data for thermal movement of various bitumens and felts and for composite membranes have been given (1). These describe the development of a thermal shock factor based on strength factors and the linear thermal expansion coefficient. Tensile and flexural fatigue tests on roofing membranes were taken at 21 and 18°C, and performance criteria were recommended. A study of four types of fluid-appHed roofing membranes under cycHc conditions showed that they could not withstand movements of <1.0 mm over joiats. The limitations of present test methods for new roofing materials, such as prefabricated polymeric and elastomeric sheets and Hquid-appHed membranes, have also been described (1). For evaluation, both laboratory and field work are needed. 

ASTM D5147, Standard Test Methods for Sampling and Testing Modified Bitumen Sheet Materials, ASTM, Philadelphia, Pa. 

In 1903 an American Society for Testing and Materials (ASTM) Committee on Road and Paving Materials was formed to develop test methods and specifications for highway materials. Test methods for volatilization, penetration, and bitumen were developed by the Office of PubHc Roads and were... 

In rubber testing the elastic structure is not damaged and the original shape is restored, since the deforming forces are lower than the recovery forces which are exerted by the elastic nature of rubber. In this respect rubber test methods differ from those applied to metals, bitumens, waxes, greases and ceramics where measurements are made of permanent deformation. 

Finally, the analytical methods used to describe petroleum must be modified for the characterization of tar sand bitumen in the same way that tests for conventional petroleum have been modified and/or replaced by newer, more relevant test methods. For example, what might appear to be a test of minimal value for conventional petroleum might afford invaluable data for determining the behavior of tar sand bitumen or the potential products from each. 

A test method (ASTM D-1552) is available for sulfur analysis the method covers three procedures applicable to samples boiling above 177°C (350°F) and containing not less than 0.06 mass % sulfur. Thus the method is applicable to most fuel oils, lubricating oils, residua, and coke, and coke containing up to 8% by weight sulfur can be analyzed. This is particularly important for cokes that originate from heavy oil and tar sand bitumen, where the sulfur content of the coke is usually at least 5% by weight. 

CEN EN 12697-11. 2012. Bituminous mixtures. Test methods for hot mix asphalt. Part 11 Determination of the affinity between aggregate and bitumen. Brussels CEN. 

Table 3.7 Properties and test methods of oxidised bitumen ...

The specified properties per performance grade asphalt binders (bitumens) are given in Table 3.8. A similar table is also provided by ASTM D 6373 (2007), which incorporates practice D 6816 (2011) for determining the critical low cracking temperature using a combination of test method D 6648 (2008) and test method D 6723 (2012) test procedures. According to ASTM D 6373 (2007), if no table is specified, the default is Table 3.8. 

In the rolling bottle test method, the affinity is determined visually by recording the degree of the bitumen coverage of the aggregate particles after hand mixing and rotating the loose bituminous mixture in the presence of water. 

However, a recent study has concluded that the steady shear flow test method and the phase angle test method can be used successfully for determining the mixing and compaction temperatures of modified bitumen, as well as of the unmodified bitumen, for laboratory use (Randy et al. 2010). 

ASTM D 2170/D 2170M. 2010. Standard test method for kinematic viscosity of asphalts (bitumens). West Conshohocken, PA ASTM International. 

CEN EN 13587. 2010. Bitumen and bituminous binders - Determination of the tensile properties of bituminous binders by the tensile test method. Brussels CEN. 

The penetration test is the most widely known test, developed at the end of the 19th century and still in use, for grading the paving bitumen. This test method also determines the consistency of the bitumen and bituminous binders at intermediate service temperature. Higher values of penetration indicate softer consistency. 

The test method is applicable to bitumen, modified binders and bituminous mastics (homogenous mixture of filler and bituminous binder) and stabilised (recovered) bitumen from bituminous emulsions, cut-back or fluxed bitumen. 

The flash and fire points of petroleum products such as bitumens and bituminous binders, having an open cup flash point above 79 C, are determined by the Cleveland open cup apparatus. For fuel oils, the most common test method used is the closed cup procedure that uses the Pensky-Martens apparatus (see ISO 2719 2002 or ASTM D 93 2013). 

This test method is applicable for graded bitumen, modified bitumen and fluxed bitumen and is used only when the binders are going to be used in surface dressings. 

This test method measures the storage stability of the modified bitumen at high temperatures. The polymer-modified bitumens in particular are known to display phase separation under certain conditions, mainly storage. 

This test method determines the specific gravity and density of bituminous binders, apart from bitumen emulsions, at 25°C 0.2°C using capillary-stoppered pycnometers. The method may be performed at other temperatures, but when doing so, the density values of the water or other liquid used should be determined. 

This test method for residue by evaporation tends to give a bitumen residue lower in penetration and ductility than the distillation test method. If the residue from evaporation fails to meet the requirements for properties specified for residue from distillation, tests shall be re-run using the distillation test method. 

This test method involves a rapid quantitative determination of the residue in bitumen emulsion using a moisture analyser. It is applicable to all non-solvent-containing emulsion types, anionic, cationic, non-polymer-modified or polymer-modified bitumen emulsions. 

This test method is for the quantitative determination of residual binder and oil distillate in bitumen emulsions for specification acceptance. The method is used to obtain residue and oil distillate for further testing. 

Figure 4.14 Apparatus for distillation test of bitumen emulsions. (Reprinted from ASTM D 6997, Standard test method for distillation of emulsified asphalt. West Conshohocken, Pennsylvania, US ASTM International, 2012. With permission [ ASTM International].)...

This test method determines the quantity of coarse particles of binder present in a bitumen emulsion by utilising sieving and, from that, storage stability. 

The above test method is similar to that specified in ASTM D 6933 (2008). The main difference is that a 0.850 mm sieve instead of a 0.5 mm sieve is used. Additionally, the temperature at which the sieve test is performed is related to the viscosity of the bitumen emulsion. For those materials whose viscosity in Saybolt Furol seconds is 100 s or less at 25 C, the test is performed at ambient temperature. For those materials whose viscosity is greater than 100 s at 25°C and those whose viscosity is specified at 50 C, use a test temperature of 50 C 3°C. 

The mass of demulsibility residue (A) in grams divided by the mass of residue in the sample of 100 g of bitumen emulsion and multiplied by 100 expresses the demulsibility percentage. More details of the test method are provided in ASTM D 6936 (2009). 

Fraass A. 1937. Test method for bitumen and bituminous mixture with specific reference to low temperature. Bitumen, Vol. 7, p. 152. 

The target bitumen content is determined by the drainage or runoff test. This is similar to the one used for hot porous asphalt (Section 5.6.1.3.4), but it is advised to use the test method proposed by the Asphalt Institute (Asphalt Institute MS-19 2008). 

To summarise the method, mixtures are made with varying bitumen emulsion content in 1% increments and subjected to a runoff test method. 

---