Example Of Engineering Report

Unconfined compression test

Objective of this experiment is to determine unconfined compression strength of a soil sample.

Description of Soil Samples:

The soil use in the lab experiment was
Description of Test Methodology:
At first the soil sample was prepared by using a Harvard miniature compaction device. Then the diameter and height of the specimen was measured, and the moist weight of the specimen was recorded. Then the specimen was centrally placed between the two loading plates of the unconfined compression machine. The top loading plate was very carefully moved just to touch the top of the specimen. In the next step, the proving ring was set dial gauge to zero. In the next step, the machine was turned on and loads (i.e., proving ring dial gauge readings) and the corresponding specimen deformations were recorded. During the load application, the rate of vertical strain was adjusted to 0.5% to 2% per minute. At the initial stage of the test, usually readings were taken every 0.01in. (0.254 mm) of specimen deformation. These measurements were taken until load reaches a peak and then decreases; or the load reached a maximum value and remained approximately constant thereafter; or deformation of the specimen was past 20% strain before reaching the peak. In the next step, the specimen was unloaded by lowering the bottom loading plate and the specimen was removed from between the two loading plates. A free-hand sketch of the specimen was drawn after failure showing the nature of the failure. Finally, the specimen was put in a porcelain evaporating dish, and the moisture content was determined after drying it in an oven to a constant weight.

Test Results:

As qu = Cu/2.
Cohesion, Cu = 380 lb/in2.

Discussion:

Conclusion:
The lab experiment was carried out safely and successfully. The procedure to find out unconfined compression strength and to evaluate the value of cohesion from the strength was gained by caring out this lab experiment. Moreover, consistency of the soil sample was determined by performing this experiment. So, three important parameter of soil has been determined rom this single experiment and the experimental results were found to be satisfactory. So, the experiment was successful.

Appendix:

Raw data sheet: