THD cone penetrometer

[SLMPicker]

Is anyone familiar with the Texas Highway Dept. cone penetrometer test, and how it may differ from a typical CPT? I have results of THD cone penetrometer tests taken in limestone near Austin, and am curious as to what the results on the boring log should look like.

 

[swaggy]

Scott, the THD penetrometer is most likely identical to the standard CPT. I used to work for the Dept of Main Roads in Queensland, Australia, and they had there own method of CPT, but it was identical to the Australian standards. Most government departments will have there own test methods or, method numbers. It would be to your advantage to phone Texas Highways and ask if it is modelled from your national standards, whatever they may be. By memory a standard CPT is the centimeters drop to the number of blows. Calculating these into a formula will give you an insitu CBR value. Regards. Kane Kreeck.
kreecky@hotmail.com.

 

The log of a CPT test is a diagram giving the point resistance of the probe versus depth for a constant velocity of penetration of the probe in the soil (typically 1cm/sec). If the probe is equipped with a lateral friction sleeve, the diagram gives in addition the lateral friction on the sleeve versus depth. Additional sensors can equip the probe and furnish pore pressure, temperature, acoustic or resistivity parameters with depth.