Cement Concrete

Civil Engineering Home for Civil Engineers

Penetration Test of Bitumen-Procedure, Apparatus, and Uses for Road Construction

Penetration test of Bitumen determines the hardness or softness of bitumen by measuring the depth in millimeter to which a standard loaded needle will penetrate vertically in five seconds while the temperature of the bitumen sample is maintained at 25 0C.

Interested One: What is Shoring? Types and Uses

Also, the Penetration test of bitumen is used to measure the consistency of bitumen. This test is applied almost exclusively to bitumen. For Tars, cutbacks, and emulsions other consistency tests are used.

Penetration test of bitumen
Fig1. Penetration test of bitumen

Equipment for Penetration test

penetrometer consisting of a needle assembly with a total weight of 100 grams and a device for releasing and locking needle in any position.

To read the penetration value, a graduated dial is attached as shown in fig.1. Penetration value can be read with this dial up to 0.1 mm.

 Penetartion test – Penetrometer
Fig2. Penetartion test – Penetrometer

Procedure  for Penetration Test of Bitumen

  1. The bitumen is softened to a pouring consistency, stirred well, and poured into the test containers. The depth of bitumen in the container is kept at least 15mm more than the expected penetration. (I.S. 1203-1958). Related:- California Bearing Ratio(CBR Test) of Subgrade Soil -Procedure, apparatus, and use for pavement Design
  2. Now the sample containers are placed in a temperature-controlled water bath at a temperature of 25 c for one hour.
  3. Then at the end of one hour, the sample is taken out of water bath and the needle is brought in contact with the surface of bitumen sample at that time reading of dial is set at zero or the reading of dial noted, when the needle is in contact with the surface of the sample.
  4. After that, the needle is released and the needle is allowed to penetrate for 5 seconds and the final reading is recorded. On that sample at least three penetration observations should be taken at distances at least 10 mm apart.  After each test, the needle should be disengaged, wiped with benzene, and dried. The amount of penetration is recorded as shown in Fig. 2.
  5. The main value of the three measurements is reported is the penetration test.
  6. The accuracy of the test depends upon pouring temperature, size of the needle, the weight placed on the needle, and test temperature.
  7. Te grade of bitumen is specified in terms of penetration value. For example, 30/40 grade bitumen indicates the penetration value of the bitumen in the range of 30 to 40 at standard test conditions.
concept of Penetration Test
Fig3. concept of Penetration Test

Readings are taken as units of penetration

Where, 1 unit =  (1/10) mm

i.e.   If penetration value is N,

Distance penetrated = (N/10) mm.

Also Read: Field Density Test of Soil by Core cutter method for soil compaction

Precautions during Penetration Test

  • The container should not be moved while needle penetrates into sample.
  • The sample should be free from any external materials.
  • Benzene is used to clean up the needle and dried before penetration.

Penetration test of bitumen is applied exclusively to bitumen. Tars being soft, penetration tests on these materials cannot be carried out.

Penetration value of different types of bitumen used in road construction range between  20 to 225. However, 30/40 and 80/100 grade bitumen is more common for road construction depending upon the type of construction and climate conditions. In hot 30/40  bitumen is preferred.

The value of temperature effects the use of the bitumen. Lower penetration grade is used in warm climate condition to avoid softening and high penetration grade range of 180/210 are used in cold climate condition to prevent it from excessive brittleness.

In the last word, the Penetration test of Bitumen is used for the Garde of bitumen material in terms of its hardness. A 70/100 grade bitumen shows that its penetration value lies between 70 & 100.

You’ll also like:

Visited 74,806 times, 10 visit(s) today

30 thoughts on “Penetration Test of Bitumen-Procedure, Apparatus, and Uses for Road Construction

  1. When I initially commented I clicked the “Notify me when new comments are added” checkbox and now
    each time a comment is added I get several emails
    with the same comment. Is there any way you can remove me
    from that service? Bless you!

  2. I’m amazed, I have to admit. Seldom do I encounter a blog that’s both equally
    educative and engaging, and without a doubt, you have hit the nail on the head.
    The problem is an issue that not enough people are speaking intelligently about.
    I am very happy I came across this during my search for something regarding this.

  3. After checking out a handful of the articles on your
    web site, I seriously like your technique of
    writing a blog. I saved as a favorite it to my bookmark site list and will be checking back in the near future.

    Please visit my website too and tell me how you feel.

  4. This is a really helpful post and very informative there is no doubt about it. I found this one pretty fascinating and it should go into my collection. Very good work!

  5. It’s actually a great and helpful piece of info. I am satisfied that
    you simply shared this helpful info with us. Please keep us informed like this.
    Thank you for sharing.

  6. Thanks for posting this info. I just want to let you know that I just check out your blog and I find it very interesting and informative. I can’t wait to read lots of your posts. Thanks alot! Know about Garmin Express Update.

  7. Your article is quite helpful! I have so many questions, and you have answered many. Thank you! Such a nice and superb article, we have been looking for this information about penetration test of bitumen . Indeed a great post about it!!If possible visit this website Csiscan.nz to gain more idea or tips on the same.

  8. Hi there, I believe your web site may be having internet browser compatibility issues. Whenever I look at your site in Safari, it looks fine but when opening in Internet Explorer, it’s got some overlapping issues. I simply wanted to give you a quick heads up! Aside from that, fantastic blog!

  9. I love what you guys tend to be up too. Such clever work and coverage!
    Keep up the wonderful works guys I’ve added you guys to my personal blog.

  10. I must say, I’m thoroughly impressed with the quality of your content. It’s evident that you put a lot of effort into crafting informative and engaging blog posts. Keep up the excellent work, and I look forward to reading more from you in the future. Thank you for sharing your knowledge with us.

Leave a Reply

Your email address will not be published. Required fields are marked *