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The effects of tornadoes on buildings are examined to determine the wind forces on structures. The American National Standards Institute (ANSI) has developed guidelines for building code requirements for the minimum wind loads a building must be designed to withstand. The conservatism or nonconservatism on the ANSI approach is evaluated by simulating tornado-structure interaction numerically with a two-dimensional fluid dynamics computer code and a vortex model. Only external pressures are considered. The computer calculations yield the following percentages of the ANSI design pressures: rigid frame, 50 to 90%; individual wall panels, 75 to 200%; and wall corners, 50 to 75%.

For high power fusion applications, a circular accelerator for heavy ions is not likely to be competitive with a linear accelerator. This is principally because one requires rather high accelerator efficiencies, and quite large average power. Efficiencies greater than or equal to 10 percent, and perhaps 30 and 50 MW of average beam power are needed. On the other hand, the linear accelerator can be built to satisfy these constraints, and in addition, it is ideally suited for multi-turn injection. A difficulty with multi-turn injection is that in typical application it is rather lossy. With care, and sufficient phase space dilution, one might hope to obtain greater than or equal to 90 percent injection efficiency, but even at these levels the large amount of beam power lost in the accumulator might have serious consequences for the machine operation. Therefore, it is desirable to be able to use ''box car'' stacking, which is essentially 100 percent without particle loss. A method of operating the linear accelerator so that the output beam is of suitable instantaneous current to permit box-car stacking with the linac output is proposed.

This compilation lists abstracts of papers, internal reports, and talks presented during 1976 at national and international meetings by members of the Earth Sciences Division, Lawrence Livermore Laboratory. Subjects include: coal gasification, gas stimulation, geothermal fields, oil shale retorting, radioactive waste management, geochemistry, geophysics, seismology, explosive phenomenology, and miscellaneous studies.

This paper reviews the developments in the mathematical modeling of groundwater systems over the past decde. The first part of the paper is devoted to a description of the physics of the different types of problems that are of interest in hydrogeology and a statement of the related initial-boundary-value problems. The various numerical techniques that have been employed to solve the governing equations are discussed in the second part. In the third section a few typical case histories are presented to illustrate the trend of progress that has occurred in the application of mathematical modeling to actual field problems.

The energy efficiency of the aqueous electrolysis step in the proposed lithium production cell was experimentally determined. Coulombic efficiencies approach 100 percent above 0.7 kA/m/sup 2/, for amalgam concentrations of 1.0--1.2 at. percent Li, and for T = 21/sup 0/C. Under these operating conditions, cell voltage is 3.1 V, and the overall energy efficiency is 82 +- 1 percent. The anodic dissolution of calcium in mixed NaOH--NaCl electrolytes was studied in the concentration region near (1.6 M NaOH, 0.05 M NaCl). It was found that passivation could be effectively prevented by additions of water-glass, Na/sub 2/O . x(SiO/sub 2/), x = 3--5. An oscillatory phenomenon was discovered where the potential of the calcium fluctuates with an amplitude of 0.4 V and a period of about 25 s. Under investigation are several new concepts for the high-energy-efficiency production of lithium and calcium metals. 4 figures.

An examination of residual stresses and strains has been carried out experimentally on structural graphite components removed from Peach Bottom High-Temperature Gas-Cooled Reactor (HTGR) fuel elements. The purpose of this work is to confirm predicted stress distributions. Twenty-nine teledial fuel elements (of six- and eight-hole design) were irradiated in the Peach Bottom HTGR to fluences of less than or equal to 4 x 10/sup 25/ n/m/sup 2/ (E greater than 29 fJ) and time-average temperatures up to 1100/sup 0/C. The irradiation history was modeled with HTGR design codes. Performance predictions were verified by in-pile thermocouples and fuel burnup measurements. The predicted irradiation-induced strains were found to be in quantitative agreement with postirradiation measurements (less than or equal to 0.5 percent shrinkage over a 70-mm diameter). As a result of the temperature distribution in the teledial bodies, compressive stresses were predicted at the periphery and tensile stresses in the inner zones. A total of 19 graphite bodies from 8 different fuel elements were examined destructively for structural integrity and residual stresses.

With the advent of vector programing it becomes necessary to provide FORTRAN users a convenient method to utilize the vector capabilities of a computer in such a way that the impact is minimal to the user. We propose to do this through four simple-to-use subroutines called the FIVE package.

The 1/5th scale model Mark I pressure suppression facility was experimentally analyzed in order to determine its fundamental modes of vibration. The results of the modal analysis revealed seven apparent modes with frequencies below 100 Hz. In this report each mode is characterized by a description of the motion, the natural frequency, and the response amplitude. The results indicate that the response of the torus to an impulsive load in the vertical direction is dominated by two modes at 12.2 Hz and 59.8 Hz.

The immediate objectives of this program are to measure the spectrum-integrated helium generation rates and cross sections of several materials in the available high intensity neutron sources, and to develop neutron dosimetry procedures using some of these materials. This requires further development of foil activation dosimetry techniques, since the cross section measurements require a detailed characterization of each neutron environment. The neutron facilities presently used in this program include accelerators producing d-T and d-Be reactions and high flux mixed-spectrum fission reactors. Most of the work reported here has focused on neutron spectra from the d-T reaction. A description is given of the preliminary analysis of wire rings included in the irradiation capsule for helium accumulation fluence dosimetry. The results show non-uniformities in the neutron fluence distribution characterizing this irradiation, and point out the value of helium accumulation fluence dosimetry for characterizing high energy (approximately 5 to 30 MeV) neutron fields. The helium accumulation fluence data are being used to adjust the neutron fluence map for calculation of final helium generation cross sections from the other RTNS-irradiated pure element specimens. Most of the specimens irradiated in the RTNS-I experiment have been analyzed for helium, and preliminary results are presented.