Download or read book Effects of Relative Density and Pulse Duration on Dynamic Response of Footings Buried in Sand written by Jack K. Poplin and published by . This book was released on 1969 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Relative Density and Pulse Duration on Dynamic Response of Footings Buried in Sand written by and published by . This book was released on 1969 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt: A series of dynamic tests on square footings buried in sand was conducted to determine the effect of varying relative density. It was found that a 60 percent increase in the stiffness of the load-displacement relation resulted from increasing relative density from 70 to 90 percent. In addition, it was determined that a dimensionless maximum load parameter-maximum displacement parameter relation developed in an earlier study involving tests at a single relative density was valid for the 70 to 90 percent relative density range. A second series of dynamic tests on square footings buried in sand was conducted to determine the influence of the duration of the dynamic load pulse. From this series of tests it was concluded that for peak dynamic loads of about one-half the static bearing capacity, pulse duration has a negligible influence on response. However, for loads slightly in excess of static bearing capacity, maximum displacement and the time to its occurrence increase with pulse duration. For each dynamic test in the relative density study, plots of computed column load, load column acceleration, footing load or reaction, and footing displacement versus time were drawn and are presented as an appendix. (Author).
Download or read book Effect of Saturation on Dynamic Response of Footings in Sand written by Jack K. Poplin and published by . This book was released on 1970 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: This investigation was undertaken to determine the effect of saturation of dense sand on the response of square footings to nuclear blast-type loading. Tests were conducted with footings on the surface and at a depth of burial equal to the footing width with a water table coincident with the plane of the footing. The results of these tests were compared with data from similar tests on dry sand from a preceding study. Saturation of dense sand had the effect of reducing maximum displacement. The displacements of surface footings were only about 30 percent of the displacement of footings on dry sand with equivalent soil density and loading condition, and the displacement of shallow buried footings was reduced by 50 percent. Empirical load-displacement curves developed from previous studies on dry sand were shown to be conservative when used to predict the response of footings on saturated dense sand. The primary difference in response occurred after peak reaction. The footings on saturated dense sand came to rest immediately, while footings on dry sand continued to displace for some short distance. This behavior was attributed to the development of transient negative pore pressures resulting from dilation of the sand. A similar laboratory investigation on a medium-density sand is recommended in order to determine whether or not any tendency toward liquefaction may occur at the lower end of the range of densities of interest for protective structure foundations. (Author).
Download or read book Dynamic Response of Rectangular Footings in Clay and Sand written by Hugh M. Taylor and published by . This book was released on 1972 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book U S Government Research Development Reports written by and published by . This book was released on 1969-10 with total page 784 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book List of Publications of the U S Army Engineer Waterways Experiment Station written by U.S. Army Engineer Waterways Experiment Station and published by . This book was released on 1976 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book List of Publications of the U S Army Engineers Waterway Experiment Station written by United States. Army. Corps of Engineers and published by . This book was released on 1976 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book List of Publications of the U S Army Engineer Waterways Experiment Station written by Waterways Experiment Station (U.S.) and published by . This book was released on 1973 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Model Study of Dynamically Loaded Square Footings on Dry Sand written by Jack K. Poplin and published by . This book was released on 1969 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: The investigation reported herein was undertaken to develop an approach to modeling displacements of surface and shallow-buried footings on dry sand subject to high-intensity, single-pulse loads. A hypothetical shallow-bured structure with an isolated footing loaded by airblast overpressure produced by detonation of a nuclear weapon was assumed for design of load pulses on nine model footings used: footing widths of 4.5, 6.0, and 7.5 in. and depth-of-burial to footing width ratios of 0, 0.5, and 1.0. The principles of similitude were used to scale length, force, and time in the models. The models were placed in mobile test bins of uniform, fine, dry sand (90 percent relative density) and subjected to dynamic and static loading. Nondimensional load-displacement relations dependent only on depth-of-burial ratio were developed relating maximum displacement to peak dynamic load, footing width, and soil shear strength gradient. When the dynamic response of the footings in the form of reaction-displacement curves was compared with static response, an increase in initial stiffness and ultimate strength was observed for dynamic loading. However, these dynamic increases were greatest when the static shear strength was lowest, i.e. footings on the surface, and were least for footings buried at a depth equal to its width where the static overburden produced a substantial increase in shear strength. (Author).
Download or read book Structural Foundations in Soils Ice Snow and Permafrost written by Guy E. Habercom and published by . This book was released on 1975 with total page 636 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Books and Library Notes written by Mississippi State University and published by . This book was released on 1973 with total page 716 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book U S Government Research and Development Reports written by and published by . This book was released on 1969-10 with total page 1340 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1969 with total page 784 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bibliography of Scientific and Industrial Reports written by and published by . This book was released on 1969 with total page 782 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Announcements written by and published by . This book was released on 1969 with total page 978 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Annual Index written by and published by . This book was released on 1969 with total page 710 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Index written by and published by . This book was released on 1969 with total page 732 pages. Available in PDF, EPUB and Kindle. Book excerpt:
