Document Type
Thesis
Date of Award
12-31-1984
Degree Name
Master of Science in Civil Engineering - (M.S.)
Department
Civil and Environmental Engineering
First Advisor
John R. Schuring
Second Advisor
R. John Craig
Third Advisor
Dorairaja Raghu
Abstract
The purpose of this thesis is to develop a dynamic testing machine for laboratory modeling of the rock fracturing phenomenon. Bearing stratum fracturing is a construction difficulty which occurs when end-bearing piles are driven to weak rock or weathered sound rock. It is a pile group effect and can result in significantly less pile carrying capacity than the final driving resistance would normally indicate.
A linear scaling factor was derived to establish similitude between the laboratory apparatus and field conditions. This scaling factor is approximate and was used for overall sizing of the apparatus and its components. A more exact similitude analysis is recommended for future experimentation with the test apparatus.
This dynamic testing machine consists of a structural steel frame with a gasoline engine which actuates a drop hammer. Stroke speeds and weight of the hammer are adjustable. The apparatus allows a reasonable dynamic simulation of full-scale pile driving process at an economical cost.
Several non-quantitative demonstration tests were performed to verify the functioning of the dynamic test apparatus. One-inch O-D diameter piles driven in clusters were driven into 28" X 28" X 10" deep mudstone and simulated rock specimens.
The driven piles causec progressive fracturing of the test specimens, as expected. The results of the demonstrative test indicated that a testing device can effectively be used for future investigation of the bearing stratum fracturing phenomenon.
Recommended Citation
Kermani, Mohammad Ali Moghaddass Zadeh, "Development of dynamic testing machine for laboratory modeling of the rock fracturing phenomenon" (1984). Theses. 3571.
https://digitalcommons.njit.edu/theses/3571
