2017年3月15日 · astm d422 - withdrawn! ... 63. ASTM D 7928-16 is the replacement standard for the hydrom portion only ...

2002年12月1日 · 63 I believe that the older USBR classification method used the 0.005 mm as the clay demarcation. ASTM D422 is now withdrawn and ASTM D7928, the current procedure for the hydrometer test does list 0.002 mm as the clay size.

2019年10月25日 · First, it is ASTM D422. There are likely other ASTM standards with the 422 designation so the letter designation is important. Second, the standard was withdrawn in 2016 so is no longer a current standard, though many still use it

2016年2月26日 · Subject: RE: D422 withdrawn Thanks for your email. I believe your understanding is correct. A new hydrometer standard is in the works as well. Some people are choosing to use D422 by referencing a historical version. Others are relying on D6913. Committee D18 is working on some guidance on what to do in the “meantime”.

2019年6月26日 · Technically ASTM D422 has been withdrawn; I've read some studies showing that the estimated particle sizes from the hydrometer portion of the test can be underestimated by up to two orders of magnitude due to the assumption of Stokes Law of falling spheres vs the disk or other shapes of real clay particles.

2011年6月6日 · You can also use ASTM D4318 (the Atterberg limits spec) to determine if a sample should be classified as an organic clay or silt via the oven-dried liquid limit test (Section 5.4). You do one LL test with material that has been air dried and compare the results to a LL test on material that has been oven-dried.

2024年4月16日 · I'm dealing with dispersive soil in a project and a geotechnical engineer told me that if we plot hydrometer and double hydrometer in one chart and if they...

2024年2月21日 · Per ASTM D7928: 1.3 When combining the results of the sedimentation and sieve tests, the procedure for obtaining the material for the sedimentation analysis and calculations for combining the results will be provided by the more general test method, such as Test Methods D6913 (Note 2).

2013年2月8日 · I have been running D422 ( Gradation with hydrometer) for years. Sometimes w/o the hydro, which I understand means that the test was not run according to the Standard, as the hydrometer portion was not optional, even though it was often treated that way. I see they have broken out the sieves only portion of the test and issued it as ASTM D 6913.

2002年9月24日 · The purpose of ASTM D1140 is to quantify the fines, but not characterize them. It is a quick and inexpensive test as compared to the hydrometer portion of ASTM D422, which both quantifies and characterizes the soil specimen with respect to its particle size.