viscosity of binder at elevated temperature using brookfield viscometer

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  1. 1. Viscosity of Binder at Elevated Temperature Using Brookeld Viscometer Priyansh Singh 16th February 2016 Priyansh Singh | 16th February 2016 0/33 Viscosity of Binder at Elevated Temperature Using Brookeld Viscometer Priyansh Singh | 16th February 2016 1/33
  2. 2. 1 What is viscosity? Introduction Use of Viscosity 2 Different Methods Empirical Methods Absolute Methods 3 Brookeld Viscometer Introduction Working Testing What is viscosity? - Introduction Table of contents Priyansh Singh | 16th February 2016 2/33
  3. 3. Viscosity Measure of the resistance to deformation of a uid under shear stress. Viscosity is measure of internal friction of a uid. This friction becomes apparent when a layer of uid is made to move with respect to other layer. Greater the friction greater the amount of force required to cause movement. Which is known as shear. What is viscosity? - Introduction What is viscosity? Priyansh Singh | 16th February 2016 3/33
  4. 4. fluid. This friction becomes apparent when a layer of fluid is made to move in relation to another layer. The greater the friction, the greater the amount of force re- quired to cause this movement, which is called shear. Shearing occurs whenever the fluid is physically moved or distributed, as in pouring, spreading, spraying, mix- ing, etc. Highly viscous fluids, therefore, require more force to move than less viscous materials. A A V2 V1 dv dx F Figure 4-1 Isaac Newton defined viscosity by considering the model represented in Figure 4-1. Two parallel flat areas of fluid of the same size A are separated by a distance dx and are moving in the same direction at different velocities V1 and V2. Newton assumed that the force required to maintain this difference in speed was proportional to the difference in speed through the liquid, or the velocity gradient. To express = viscosity = = s s . The fundamental unit of viscos poise. A material requiring a s dyne per square centimeter to p of one reciprocal second has a vis or 100 centipoise. You will encou surements expressed in Pascal- milli-Pascal-seconds (mPas); t International System and are som erence to the CGS designations. is equal to ten poise; one milli-Pas to one centipoise. Newton assumed that all mater temperature, a viscosity that is shear rate. In other words, twice th the fluid twice as fast. As we shall see, Newton was o 4.3 Newtonian Fluids This type of flow behavior whic for all fluids is called, not surprisin is, however, only one of several ty you may encounter. A Newtonian graphically in Figure 4-2. Grap relationship between shear stres Newtons Law Newton assumed that the force required to maintain this difference in speed was proportional to the difference in speed through the liquid, or the velocity gradient What is viscosity? - Introduction Viscosity Priyansh Singh | 16th February 2016 4/33
  5. 5. = V iscosity dv dx = Shear rate F A = Shear stress F A = dv dx = Shear Stress Shear Rate What is viscosity? - Introduction Viscosity Priyansh Singh | 16th February 2016 5/33
  6. 6. 1 What is viscosity? Introduction Use of Viscosity 2 Different Methods Empirical Methods Absolute Methods 3 Brookeld Viscometer Introduction Working Testing What is viscosity? - Use of Viscosity Table of contents Priyansh Singh | 16th February 2016 6/33
  7. 7. Usefull Behaviour Binder Grading What is viscosity? - Use of Viscosity NECESSITY of Viscosity Measurement Priyansh Singh | 16th February 2016 7/33
  8. 8. IS 73 : 2013 Table 1 Requirements for Paving Bitumen (Clause 6.2) Paving GradesSl No. Characteristics VG10 VG20 VG30 VG40 Me (1) (2) (3) (4) (5) (6) i) Penetration at 25C, 100 g, 5 s, 0.1 mm, Min 80 60 45 35 IS 1 ii) Absolute viscosity at 60C, Poises 800-1 200 1 600-2400 2 400-3 600 3 200-4 800 IS 1 iii) Kinematic viscosity at 135C, cSt, Min 250 300 350 400 IS 1 iv) Flash point (Cleveland open cup), C, Min 220 220 220 220 IS 1 v) Solubility in trichloroethylene, percent, Min 99.0 99.0 99.0 99.0 IS 1 vi) Softening point (R&B), C, Min 40 45 47 50 IS 1 vii) Tests on residue from rolling thin film oven test: a) Viscosity ratio at 60C, Max b) Ductility at 25C, cm, Min 4.0 75 4.0 50 4.0 40 4.0 25 IS 1 IS 1 precautions mentioned therein.All these samples from individual containers shall be stored separately. 7.4 Number of Tests 8 PACKING AND MARKING 8.1 Packing What is viscosity? - Use of Viscosity Binder Grading Priyansh Singh | 16th February 2016 8/33
  9. 9. Effect of Processing By viscosity measurement the effective change in binder can be assessed. Formulation changes Potential change in asphalt behavior can be accessed by viscosity measurement. Aging Phenomena Binder aging can be assessed by change in viscosity measurement. Production Temperature The mixing and compaction temperatures of the asphalt concrete can be determined by viscosity measurement. What is viscosity? - Use of Viscosity NECESSITY of Viscosity Measurement Priyansh Singh | 16th February 2016 9/33
  10. 10. What is viscosity? - Use of Viscosity Determination of mixing and compaction Temperatures Priyansh Singh | 16th February 2016 10/33
  11. 11. 1 What is viscosity? Introduction Use of Viscosity 2 Different Methods Empirical Methods Absolute Methods 3 Brookeld Viscometer Introduction Working Testing Different Methods - Empirical Methods Table of contents Priyansh Singh | 16th February 2016 11/33
  12. 12. These methods determines the viscosity without addressing the constitutive relationship. Capillary Viscometer Relation with other test. Different Methods - Empirical Methods Empirical Methods Priyansh Singh | 16th February 2016 12/33
  13. 13. 1 What is viscosity? Introduction Use of Viscosity 2 Different Methods Empirical Methods Absolute Methods 3 Brookeld Viscometer Introduction Working Testing Different Methods - Absolute Methods Table of contents Priyansh Singh | 16th February 2016 13/33
  14. 14. These methods uses the basic stress strain relationship to determine viscosity of material. Rotational Viscometer. Shear Rheometer. Different Methods - Absolute Methods Absolute Methods Priyansh Singh | 16th February 2016 14/33
  15. 15. 1 What is viscosity? Introduction Use of Viscosity 2 Different Methods Empirical Methods Absolute Methods 3 Brookeld Viscometer Introduction Working Testing Brookeld Viscometer - Introduction Table of contents Priyansh Singh | 16th February 2016 15/33
  16. 16. Brookeld Viscometer - Introduction Brookeld Viscometer Priyansh Singh | 16th February 2016 16/33
  17. 17. STEPPER MOTOR CLUTCH DIAL PIVOT SHAFT PIVOT CUP GUARDLEG SPINDLE SAMPLE CONTAINER HOUSING GEAR TRAIN POINTER CALIBRATED SPIRAL SPRING JEWELLED BEARING Figure 3-1 over 80 years of c sound foundation f a starting point from can be explored. 3.4.1 Record Ke We recomm tion always be measurement; cessory), rotatio sions, sample te sample prepara or not the spind Forms supplied Viscometer are 3.4.2 The Spind Examine ea corroded or dam dimensions, a f Since all spindle Brookeld Viscometer - Introduction Components of Brookeld Viscometer Priyansh Singh | 16th February 2016 17/33
  18. 18. 1 What is viscosity? Introduction Use of Viscosity 2 Different Methods Empirical Methods Absolute Methods 3 Brookeld Viscometer Introduction Working Testing Brookeld Viscometer - Working Table of contents Priyansh Singh | 16th February 2016 18/33
  19. 19. Brookeld Viscometer - Working Principle of Rotational Viscometer Priyansh Singh | 16th February 2016 19/33
  20. 20. It measures the torque required to rotate an immersed element (Spindle) in a uid. Spindle is driven by a motor through a calibrated spring. Deection (tension) in spring is indicated by digital display. For a given viscosity, viscosity drag or resistance to ow is proportional to spindle speed of rotation. Brookeld Viscometer - Working Principle of Rotational Viscometer Priyansh Singh | 16th February 2016 20/33
  21. 21. instrument (dyne-cm) L = effective length of spindle (cm) (see Appendix A.4) Rc Rb L Rc should not exceed 2Rb for well defined 5.1 Advanced Methods for Rheological Analysis As mentioned in Chapter 1, those who follow the Academic school of thought on viscosity measurement have more complex needs than those who follow the Pragmatic or Theoretical schools. They need viscos- ity data that are defined in rheological terms. This usu- ally requires a complete mathematical description of the Viscometers operating parameters and an analysis of the rheological behavior of the fluid being studied. Previous chapters have described various types of fluid behavior and their relationship to measurements made with Brookfield Viscometers/Rheometers and accessories. The Appendix details the significant operating parameters of this equipment and presents simplified formulas for obtaining shear rate and shear stress values. However, for many this information is still inadequate to perform the type of analysis they require. Having identified a particular flow behavior and defined it mathematically, these people need more information to understand how the fluid will react in a certain situation, and how to control that reaction. If is for these people that this chapter is provided. In it you will find basic formulas from which the simplified shear rate and shear stress information in SHEAR STRESS (dynes/cm2): = M 2 Rb2L 2 Rc2 Rb2 x2 (Rc2 Rb2) SHEAR RATE (sec-1): = (1) (2) (3) VISCOSITY (poise): = Definitions: = angular velocity of spindle (rad/sec) [ = N], N = RPM Rc = radius of container (cm) Rb = radius of spindle (cm) x = radius at which shear rate is being calculated (cm) M = torque input by instrument (dyne-cm) L = effective length of spindle (cm) (see Appendix A.4) 2 60( ) CHAPTER 5: Data Analysis system. If the dispersed phase has a tendency to settle, producing a non-homogeneous fluid, the rheological characteristics of the system

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