A Caltech Library Service

Upthrow of objects due to horizontal impulse excitation

Psycharis, Ioannis N. and Jennings, Paul C. (1985) Upthrow of objects due to horizontal impulse excitation. Bulletin of the Seismological Society of America, 75 (2). pp. 543-561. ISSN 0037-1106.

PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


The phenomenon of upthrow of rigid blocks, excited into motion by horizontal impulses, is examined in this study. A simple foundation model is used, consisting of two sets of springs and dashpots; one set near each corner of the block. Each set consists of vertical and horizontal elements. The vertical springs are not permitted to take tensile forces, so separation of the block from the ground is allowed. The associated horizontal spring separates along with the vertical spring. The response can be separated into three regimes, namely, full contact, partial uplift, and complete separation. Analytical expressions for the response are given for the first two cases; the third case is simply rigid body motion. The overall response is nonlinear and analytical criteria for upthrow were not found. The minimum value of the impulse required for complete separation, expressed as a normalized initial velocity, was determined numerically and a parametric investigation performed. Although the irregularity of the results does not allow many general conclusions to be drawn, it was found that for short blocks, a decrease in the stiffness of the horizontal foundation springs required larger impulses for separation. These effects had mixed results for tall blocks.

Item Type:Article
Related URLs:
URLURL TypeDescription;75/2/543PublisherArticle
Additional Information:© 1985 Seismological Society of America. Manuscript received 22 November 1983.
Issue or Number:2
Record Number:CaltechAUTHORS:20140813-084600021
Persistent URL:
Official Citation:Psycharis, I. N., & Jennings, P. C. (1985). Upthrow of objects due to horizontal impulse excitation. Bulletin of the Seismological Society of America, 75(2), 543-561.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:48478
Deposited By: Jason Perez
Deposited On:13 Aug 2014 19:59
Last Modified:03 Oct 2019 07:04

Repository Staff Only: item control page