NEHRP Clearinghouse

Title
Optimum Seismic Protection for New Building Construction in Eastern Metropolitan Areas. Ground Motions Measured by VM-1.
File
PB80106370.pdf
Author(s)
Whitman, R. V.; Christian, J. T.; Trudeau, P. J.
Source
National Science Foundation, Washington, DC. Engineering and Applied Science., September 1972, 22 p.
Identifying Number(s)
INTERNAL STUDY-17
Abstract
Field measurements of vibratory ground motions were carried out in the Boston, Massachusetts area using the portable VM-1 instrument to obtain acceleration records. This report describes the places where the data were obtained. It includes soil profiles and typical records of the motions. Some preliminary analyses of the data and conclusions are provided. Measurements of the ambient vibrations due to traffic were made at five sites. Two five pound dynamite charges were exploded in a boring near Site One as the signal for the measurements at Site Six. The explosions were at a depth of about 50 feet. They were set off between 5:00 and 6:00 A.M. to reduce background noise due to traffic. The profiles of these six sites are presented. The VM-1, Vibration Monitor, consists of an acceleration transducer acting as a sensor and a separate recording and filter unit. The recording is done on heat sensitive paper. Typical ambient motion records made at the first five sites are presented. The predominant frequencies picked out by the visual examination of the records are tabulated. The records from the dynamite explosions are presented and the predominant frequencies are tabulated.
Keywords
Ground motion; Earthquake engineering; Boston (Massachusetts); Earth movements; Massachusetts; Vibration tests; Seismic waves