One-dimensional Stress Wave Propagation in Soils

One-dimensional Stress Wave Propagation in Soils
Author: Lynn Seaman
Publisher:
Total Pages: 175
Release: 1966
Genre:
ISBN:

Soil behavior during stress wave propagation was studied on a sand and two clays by making one-dimensional wave propagation tests on 5-meter long columns of the soils. Attempts were made to predict this behavior by determining soil properties in dynamic compression tests on small samples and by using these properties in a variety of mathematical models for soils. In all the wave propagation tests, stress and acceleration records were very similar, showing that the three soils differ in degree, not in kind. Peak stress and particle velocity attenuated to 20-40% of the peak value in the length of the 5-meter column. Two theoretical soil models were analyzed: one to investigate the effect of combined time-dependent and time-independent dissipation, and one to study the effects of nonlinear stress-strain relations and geostatic stress. Comparison of the theoretical predictions from the first of these and two previously studied models (using properties obtained from compression tests on soil samples) with the wave propagation results shows: (1) For clays the arrival time of the wave at the column base was within 10% of that calculated from the tangent modulus, and for sand it was within 25%. (2) Attenuation of peak stress and particle velocity was predicted within plus or minus 50% at the base of the column (5-meter length). (Author).

Study of Wave Propagation in Confined Soils

Study of Wave Propagation in Confined Soils
Author: D. Hampton
Publisher:
Total Pages: 159
Release: 1968
Genre: Soils
ISBN:

The report covers an experimental program dealing with the propagation of stress waves through horizontal columns of soil. The soil specimens were contained in a segmented hollow cylinder consisting of 1-in.-long aluminum sections of about 3 in. diam, with 1/8-in. foam rubber spacers on each end. Two soils were used in the study, EPK clay and McCormick Ranch sand. Embedded stress and strain gages were used to measure time histories and information was gained concerning stress-strain characteristics. Data were obtained on peak stress attenuation, velocities of wave propagation and peak stress, wave front development, and experimental error. Two test series were run. The first was for the purpose of perfecting the confining chamber and shock tube apparatus. The second was the main test series to be used for analysis. In the latter, data analysis took the form of a comparison of laboratory wave propagation results with predictions by a one-dimensional lumped parameter computer code developed at IITRI. (Author).

Procedures for Prediction of Ground Shock Phenomena Based on One-dimensional Shock Propagation Considerations

Procedures for Prediction of Ground Shock Phenomena Based on One-dimensional Shock Propagation Considerations
Author: James V. Zaccor
Publisher:
Total Pages: 222
Release: 1967
Genre: Shock waves
ISBN:

The report describes a definitive experimental study in which shock-induced square-wave pulses in soil were observed to give way to decaying pulse shapes, as in a gas shock tube, and rapid attenuation of peak stress occurred thereafter due to nonlinear propagation in the rarefaction. In the study three different duration pulses were applied to an 8-ft vertical column of granular material confined under boundary conditions leading to a stress-strain (Sigma - Epsilon) behavior described by d to the 2nd power Sigma/d Epsilon to the 2nd power> 0, i.e., a strain-hardening type of response. Applied stresses ranged from 50 to 500 psi. The report describes a simple modification to be applied to the prediction procedure described in the first report of this series in order to take into account, to a first approximation, the nonlinear propagation of unloading waves that occurs in real media because of nonlinear stress-strain behavior in the unloading branch. The procedure which predicts stress and motion histories based on the conservation laws, a measured constitutive relationship, and the applied pressure-time profile, is demonstrated by predicting the entire sequence of an experimentally observed square-wave pulse transformation into a decaying pulse. (Author).

Application of Stress-wave Theory to Piles

Application of Stress-wave Theory to Piles
Author: Frans B. J. Barends
Publisher: Taylor & Francis
Total Pages: 736
Release: 2022-06-03
Genre: Technology & Engineering
ISBN: 1351466283

Comprising 97 papers on Geotechnical & environmental aspects (Pile-soil modelling, vibrations); Dynamic testing (Equipment & data acquisition systems); Performance during installation (Driving equipment, hammer-pile-soil system); Reliability of predictions (Theory versus experiment and simulation). Each part starts with a lecture by invited keynote speakers; followed by a general report on the papers. New themes considered are environmental aspects related to vibration and noise & the reliability of predictions emphasizing the validation of theoretical methods & practical experience.

Soil Dynamics

Soil Dynamics
Author: Tien-hsing Wu
Publisher: T. H. Wu
Total Pages: 296
Release: 1971
Genre: Technology & Engineering
ISBN:

Fundamentals of soil dynamics with emphasis on soil behavior in analyses.