SOFTENING POINT OF BITUMEN
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POLYTECHNIC MERLIMAU, MELAKA
CIVIL ENGINEERING DEPARTMENT
HIGHWAY LABORATORY
SOFTENING POINT OF BITUMEN
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SOFTENING POINT OF BITUMEN
NO CONTENT PAGE
1 INTRODUCTIONS 2
2 THEORY & OBJECTIVE 3-4
3 APPARATUS 5-6
4 PROCEDURE 7-8
5 RESULT AND CALCULATION. 9
6 DISSCUSSION 10
7 CONCLUSION 11
8 APPENDIX 12
9 REFERENCE 13
SOFTENING POINT OF BITUMEN
Softening point denotes the temperature at which the bitumen attains a particular degree of softening under the specifications of test. The test is conducted by using Ring and Ball apparatus. A brass ring containing test sample of bitumen is suspended in liquid like water or glycerine at a given temperature. A steel ball is placed upon the bitumen sample and the liquid medium is heated at a rate of 5o C per minute. Temperature is noted when the softened bitumen touches the metal plate which is at a specified distance below. Generally, higher softening point indicates lower temperature susceptibility and is preferred in hot climates. Figure shows Softening Point test setup.
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INTRODUCTION
SOFTENING POINT OF BITUMEN
Bitumen does not suddenly change from solid to liquid state, but as the temperature increase, it gradually becomes soften until it flows readily. The softening point is the temperature at which the substance attains particular degree of softening under specified condition of test. For bitumen it is usually determined by Ring and Ball apparatus.
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THEORY
SOFTENING POINT OF BITUMEN
To determine characteristic of bitumen when the bitumen become liquid.
To determine the softening point of a bitumen sample using the ring and the ball apparatus.
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OBJECTIVE
SOFTENING POINT OF BITUMEN
No. APPARATUS PICTURE
1. RING AND BALL APPARATUS
2.BEAKER
3. SPATULA
4. THERMOMETER
5. BITUMEN
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APPARATUS
SOFTENING POINT OF BITUMEN
1. Sample material is heated to a temperature between 75 and 100°C above the approximate softening point until it is completely fluid.
2. The bitumen test sample is placed in the brass ring and the ring is suspended in water at a given temperature.
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PROCEDURE
SOFTENING POINT OF BITUMEN
3. A steel ball is put on the bitumen and the water bath is heated such that the temperature of water bath rises by 5°C per minute.
4. The temperature at which the softened bitumen touches the metal plate placed at a specified distance below the ring is noted. This temperature is called the softening point of the bitumen. Higher the softening point, harder the grade of the bitumen
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SOFTENING POINT OF BITUMEN
TABLE 1: SOFTENING POINT TEST
NUMBER OF TEST SOFTENING POINT (c)
BALL A 57°c
BALL B 57.4°c
AVERAGE TEMPERATURE 57.2°c
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RESULT AND CALCULATION
SOFTENING POINT OF BITUMEN
Since the softening point of bitumen material does not take place at any definite
temperature, but involves gradual change in consistency with increasing temperature, any
procedure that is adopted for determining the softening point must be arbitrary nature. The
procedure in common use in highway materials laboratories is known as the ring and ball method
and may be applied to semi solid and solid material. The ring and ball method is also used to
determine the penetration index and in conjunction with penetration and loading time. The
softening point is taken to be the temperature at which bitumen material touches the bottom of
the container.
Being very simple in concept and equipment, the ring and ball test has remained a
valuable consistency test for control in refining operations, particularly in the production of air-
blown bitumen. It is also an indirect measure of viscosity or, rather, the temperature at which a
given viscosity is evident. The softening point value has particular significance for materials
which are to be used as thick films, such as joint and crack fillers and roofing materials. A high
softening point ensures that they will not flow in service. For a bitumen of a given penetration
(determined at 25℃), the higher the softening point of the lower the temperature sensitively.
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DISCUSSION
SOFTENING POINT OF BITUMEN
Rigid adherence to the prescribed preparation of specimens and heating is absolutely
essential for reproducibility of the results. The mean temperature of the two specimens (which
shall not differ by more than 1 Celsius) is recorded as the softening point. This temperature is to
be used in conjunction with the penetration value to obtain the Penetration Index (PI).
Softening point indicates the temperature at which binders possess the same viscosity.
Bituminous materials do not have a melting point. Rather, the change of state from solid to liquid
is gradual over a wide range of temperature. Softening point has particular significance for
materials to be used as joint and crack fillers.
Higher softening point ensures that they will not flow during service. Higher the softening point,
lesser the temperature susceptibility. Bitumen with higher softening point is preferred in warmer
places.
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CONCLUSION
SOFTENING POINT OF BITUMEN
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APPENDIX
SOFTENING POINT OF BITUMEN
1. www.arusniaga.com
2. Highway Engineering Book of Polytechnic Merlimau Melaka C 1030
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REFERENCE