proof of reading

One of the examination OSAH emphasize to conduct is manual analysis of soil samples to determine quantitative and qualitative of soil and to provide a prowler classification of the soil. Thumb Penetration Test

The thumb penetration test can be used to evaluated the unconfined compressive of costive soils. The thumb partition test involves to press thumb into the examiner’s soil after you make it as a ball. Based on the length of the thumb nail we determine the type of soil. Type A it the thumb penetration not go away in length , while type B soil its go further than A, type C go more further than A and B.

In our experiment, after we were digging and passed the grass layer, we grabbed some of soil from the end of the hole we made at the back yard of one of our friend’s house. We noticed that the soil need great effort to be penetrated by thumb as we press the thumb firmly into soil and did not go further which mean that the type of soil is A ( see figure # ).

Pocket penetrometer

The Pocket Penetrometer is designed as a handy device can be used to check visual classification of soils filed personnel. As the result of the reading we can verify where excavation side walls require shoring or not based on OSHA cohesive solids classifications.

We used in this test spring operated instruments to determine unconfined compressive strength of saturated cohesive soil. The reading displays when the pushed the instrument into the soil via indictor sleeve. the penetrometer is calibrated in ether tons per square foot or kilograms per square centimeter. However, the error rate for this experiment is between +-20 to 40%.

In our soil test by using the pocket penetrometer we collect some of soil from the bottom of the hole we made to make sure that the we passed the grass’s layer. We put the soil sample in paper cup (see figure). the white ring on the barrel of the penetrometer is designed to maintain the test reading on the scale for easy reading. After we grip the handle and push the tip of the penetrometer into the sample soil , so the groove marked on the tip.The reading taken from the lower side of the white ring shows that 2.0 TSF. That’s mean the soil are cohesive with an unconfined compressive as the strength is greater than 1.5 tons per square foot.