94 Matching Results

Search Results

Advanced search parameters have been applied.

Finite Element Analysis of EC Insert Plug

Description: The proposed EC calorimeter insert plug was modeled with ANSYS to verify that the shell thickness calculated with beam formulas are adequate. The finite element model and dimensions is shown in Fig. 1. The geometry and shell thicknesses used were the best numbers available as of 3/28/86. The model includes only the inner and outer shells and intermediate structural discs. The total weight of the plug is calculated to be 75000 lbs. The plug is supported against this weight at the four nodes indicated in Fig. 1. A vertical constraint was used. The calorimeter plates are not explicitly modeled. Their weight is placed on the inner shell by giving the shell material an appropriate density and applying a global acceleration. In addition to the weight loading, there will also be a pressure loading applied to both end plates as a result of preloading the calorimeter plates compressively. This pressure is estimated to be 20 pSi, and was represented in the model as a uniform pressure applied across each end plate. The large axial force produced by this pressure precludes the possibility of attaching the inner shell to both end plates. Such attachments would be under unreasonably high stress as the plates were preloaded, and the inner shell would be under a state of tension in trying to resist the axial force. In the real structure, the inner shell will be attached to at most one of the end plates. The axial force is then developed solely in the outer shell, which has a considerable area of attachment. To emulate this in the finite model, nodal coupling was used to couple the shell laterally to both end plates and all intermediate discs to ensure weight transfer, but axially the shell was only coupled to one of the end plates. The materials ...
Date: April 1, 1986
Creator: Wands, R.
Partner: UNT Libraries Government Documents Department

Mineralogy and Distribution of Hydrothermal Mineral Zones in Los Azufres (Mexico) Geothermal Field

Description: General features of the geometry of Los Azufres reservoir have been defined through the mapping of hydrothermal mineral alteration zones. Hydrothermal alteration has been studied in cuttings and drill cores from most of the active wells. X-ray diffraction microprobe analysis and classical optical methods have been employed for the identification of primary and authigenic minerals in fresh and altered samples. Observed patterns of alteration have been correlated with temperature and patterns of fluid circulation. The resulting model depicts a body of geothermal fluid at depth, which ascends and discharges through two main fracture systems. These two circulation zones are characterized by concentric aureoles of increasing hydrothermal alteration towards quasivertical axes. The overall pattern could be described as a dome structure produced by the abnormal thermal gradient, distorted by the effects of active upward circulation of the fluids.
Date: December 15, 1983
Creator: Cathelineau, M.; Oliver, R.; Izquierdo, G.; Garfias, A.; Nieva, D. & Izaguirre, O.
Partner: UNT Libraries Government Documents Department

A Review of the Geothermal Reservoir Well Stimulation Program

Description: Republic Geothermal, Inc., and its subcontractors have planned and executed four experimental fracture stimulation treatments under the Department of Energy-funded Geothermal Reservoir Well Stimulation Program (GRWSP). The 2-year program, begun in February 1979, is Ultimately to include six full-scale field hydraulic and chemical stimulation experiments in geothermal wells. This paper describes the overall program and the four treatments completed to date. The GRWSP is organized into two phases. Phase I consists of literature and theoretical studies, laboratory investigations, and numerical work. The main purpose of this work is to establish the technological bases for geothermal well stimulation design. Phase I1 will include the planning, execution, and evaluation of six well stimulation treatments which utilize the technology developed in Phase I. Two stimulation experiments were performed at the Raft River, Idaho, known geothermal resource area (KGRA) in late 1979. This is a naturally fractured, hard rock reservoir with a relatively low geothermal resource temperature 149 C {+-} (300 F{+-}). A conventional planar hydraulic fracture job was performed in Well RRGP-5 and a ''Kiel'' dendritic, or reverse flow, technique was utilized in Well RRGP-4. In mid-1980, two stimulation experiments were performed at the East Mesa, California, KGRA. The stimulation of Well 58-30 provided the first geothermal well fracturing experience in a moderate temperature, 177 C {+-} (350 F{+-}), reservoir with matrix-type rock properties. The two treatments consisted of a conventional hydraulic fracture of a deep, low-permeability zone and a mini-frac ''Kiel'' treatment of a shallow, high-permeability zone in the same well. The stimulation experiment results to date were evaluated using short-term production tests, conventional pressure transient analysis, interference pressure data, chemical and radioactive tracers, borehole acoustic televiewer surveys and numerical models. This combination of evaluation techniques yielded an interpretation of fracture geometry and productivity enhancement. However, the evaluation of artificially induced fractures ...
Date: January 1, 1981
Creator: Campbell, D. A.; Hanold, R. J.; Sinclair, A. R. & Vetter, O. J.
Partner: UNT Libraries Government Documents Department

A feasibility study for the spherical torus experiment

Description: Oak Ridge National Laboratory (ORNL) proposes to build the Spherical Torus Experiment (STX), a very low aspect ratio toroidal confinement device. This proposal concentrates on tokamak operation of the experiment; however, it can in principle be operated as a pinch or reversed-field pinch as well. As a tokamak, the spherical torus confines a plasma that is characterized by high toroidal beta, low poloidal beta, large natural elongation, high plasma current for a given edge q, and strong paramagnetism. These features combine to offer the possibility of a compact, low-field fusion device. The figure below shows that when compared to a conventional tokamak the spherical torus represents a major change in geometry. The primary goals of the experiment will be to demonstrate a capability for high beta (20%) in the first stability regime, to extend our knowledge of tokamak confinement scaling, and to test oscillating-field current drive. The experiment will operate in the high-beta, collisionless regime, which is achieved in STX at low temperatures because of the geometry. At a minimum, operation of STX will help to resolve fundamental questions regarding the scaling of beta and confinement in tokamaks. Complete success in this program would have a significant impact on toroidal fusion research in that it would demonstrate solutions to the problems of beta and steady-state operation in the tokamak. The proposed device has a major radius of 0.45 m, a toroidai field of 0.5 T, a plasma current of 900 kA, and heating by neutral beam injection. We estimate 30 months for design, construction, and assembly. The budget estimate, including contingency and escalation, is $6.8 million.
Date: October 1, 1985
Creator: Lazarus, E & Peng, Yueng Kay Martin
Partner: UNT Libraries Government Documents Department

Considerations Against a Force Compensated Coil

Description: The cost of structural components in a large superconducting coil may well exceed the coil and cryostat cost. As a result, the idea of constructing a system composed of two different coil types assembled in such a way that the forces balance and reduce the total structural requirement is oft proposed. A suitable geometry has never been found for the fundamental reason that there can be no force compensated solution. In this paper, the general problem is presented and an analysis of the energy stored and stresses produced in the structure are described in a fundamental way. Finally, the relation between structural mass M and stored energy E, M {ge} {rho}E/{sigma}{sub w}, that is valid for all, magnetic systems is developed, where {rho} is the density of the structure and {sigma}{sub w} is the working stress in the structure.
Date: August 1, 1988
Creator: Hassenzahl, W.
Partner: UNT Libraries Government Documents Department

Trip Report-Visit to CERN July 5 to August 5, 1985

Description: The present visit to CERN was as a result of an invitation from Dr. Colin Johnson of the Antiproton Accumulator (AA) group. Two activities were planned for this visit. First, the second beam test of one of the original Fermilab lithium lenses (serial No.2). Second, the installation and beam tests for a new Fermilab lens of improved design (serial No.5). It should be mentioned here that CERN, after realizing the possible gains to be obtained, has started a considerable development effort in short focal length lenses. Presently they have 3 operational lithium lenses, transformers and power supplies for tests. They are in the process of constructing 3 other transformers and designing lenses of 4 cm diameter (twice the present Fermilab lenses). Fermilab should devote some added effort in the field to maintain the initiative. The first beam test of lens No.2 was performed during the summer of 1983, when the lens was used as an antiproton collecting lens. For this test the original lens was used as a strong focusing element in the 26 GeV proton beam in conjunction with a current carrying target Preliminary tests for this geometry were conducted during 1984, when the lens was exposed to over 2*E6 pulses at 320kAmps and 1.3*E13 protons per pulse. Lens No.5 was installed as an antiproton collecting lens, immediately following the AA production target, in a geometry similar to the one designed for the Tevatron 1 project at Fermilab. Targets of a different design than the one use normally at CERN were also required. After completion of the antiproton yield measurements and optimization the lens was left in the beam during regular operation for antiproton accumulation. During antiproton accumulation for the Lear accelerator new records were achieved on the accumulation yield and accumulation rate of antiprotons for the AA machine. ...
Date: September 13, 1985
Creator: Hogvat, C.
Partner: UNT Libraries Government Documents Department

Reservoir Behaviour in a Stimulated Hot Dry Rock System

Description: Research into the stimulation of hot dry rock (HDR) systems in crystalline rock has been underway in Cornwall, England for several years. Two deviated wells were drilled to a depth of 2100 m in 1981 with an interwell separation of 300 m. These wells were connected by massive hydraulic injections using water, but the interconnection was insufficient to permit long term circulation without excessive water losses. In 1985 a third well was drilled to a depth of 2600 m in a direction chosen from the analysis of the reservoir behavior during the previous circulation. A massive stimulation (200 l/s, 75 bbl/min) of gel was used to connect the wells and circulation was re-established in August 1985. Reservoir models have been developed from hydraulic analyses, thermal behavior, microseismic mapping, tracer dispersion and chemical modeling. The system behaves like an interconnected network of flow paths with a few dominant routes acting as flow conduits. The storage is associated with pressure dependent joint compliance, but it is isolated from the dominant flow paths. No unique physical model has yet been derived but the various techniques have been used to establish constraints on the geometry and nature of the heat transfer regions. The experiments are still in progress.
Date: January 21, 1986
Creator: Batchelor, Anthony S.
Partner: UNT Libraries Government Documents Department

Reinjection Model Studies in Fractured and Homogeneous Geothermal Systems

Description: Reinjection of geothermal waste waters has become an important topic of interest for industry as well as for research. The environmental concerns due to chemical composition of geothermal waste waters had urged the industry to dispose it underground. In several field applications no interference due to thermal front breakthrough was observed on the other hand some cases are reported where reinjection had caused severe declines in energy production due to unexpected breakthrough of injected water. Several analytical and numerical studies are available where the effect of fractures on the movement of thermal front are discussed. It was shown that when the conduction heat transfer from matrix to fracture dominates, retardation of the thermal front movement will be observed. Bodvarsson and Pruess considered the above problem in a five-spot well pattern. They observed as the amount of fluid injected reaches the amount produced, the long-term energy output of the system increases. Pruess in his study compares the behavior of porous medium and fractured medium in terms of pressure decline due to production. Temperature and pressure profiles are presented between an injector and a producer where heating of the injected water in porous medium and in fractured medium with small fracture spacing was high compared to a larger fracture spacing. Such observations from the numerical studies were checked against some limited field examples. However understanding of the injection effects in fractured reservoirs is limited. This work presents the results of laboratory experiments where effects of reinjection on temperature and pressure behavior of a porous medium and a fractured medium were investigated. The porous medium was a crushed limestone pack, with 10 mm average particle size, packed in a 3-D box model where injection and production ports are located on the diagonal ends simulating a five-spot pattern. The fractured medium was made from ...
Date: January 21, 1986
Creator: Okandan, E. & Hosca, H.
Partner: UNT Libraries Government Documents Department

A Data-Management System for Areal Interpretive Data for the High Plains in Parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming

Description: From abstract: The High Plains Regional Aquifer System Analysis study has developed a regional water-resources (and related) data storage and retrieval system to organize and preserve areal interpretive data. The system is general and can easily be adapted for other studies. This report documents the High Plains data base as well as the general system that is independent of the High Plains area.
Date: December 1982
Creator: Luckey, Richard R. & Ferrigno, Carmelo F.
Partner: UNT Libraries Government Documents Department

A SURFACE CRYSTALLOGRAPHY STUDY BY DYNAMICAL LEED OF THE (sqrt3xsqrt3)R30o CO STRUCTURE ON THE Rh(111) CRYSTAL SURFACE

Description: The atomic positions of the Rh(111) + ({radical}3 x {radical}3)R30{sup o} CO and CO{sub 2} surfaces are analyzed by dynamical LEED. The Rh(111) + ({radical}3 x {radical}3)R30{sup o} CO and CO{sub 2} systems produce identical I-V curves, confirming the dissociation of CO{sub 2} to CO on this surface. The adsorbed CO is found to stand perpendicular to the surface with the carbon end down at an atop site (that is, terminally bonded). The CO overlayer spacings are d{sub RhC} = 1.95 {+-} 0.1 {angstrom} and d{sub CD} = 1.07 {+-} 0.1 {angstrom}. This geometry yields a Zanazzi-Jona R-factor of 0.40 and a Pendry R-factor of 0.50.
Date: September 1, 1980
Creator: Koestner, R.J.; Van Hove, M.A. & Somorjai, G.A.
Partner: UNT Libraries Government Documents Department

Hydrogen Chemisorption on Pt Single Crystal Surfaces in Acidic Solutions

Description: Hydrogen chemisorption from dilute acidic solution onto Pt single crystal surfaces was examined using an electrochemical cell directly coupled to LEED/Auger analytical system. No pre-anodization was used prior to observing hydrogen adsorption by cyclic voltammetry so that clean surfaces having the ordered structures indicated by LEED were studied. The problem of contributions from non-ordered parts of the electrode like support wires and edges was solved by using a gold evaporation masking technique. The specific contribution of atomic imperfections to the voltammetry curve was deduced from the ordered and countable imperfections occurring on high Miller index single crystal surfaces that have a stepped structure. The H-Pt bond energy Has found to be structure sensitive, and sensitive both to local site geometry and long range order in the surface. The bond strength was found to vary systematically: n(111)x(100) > (100) > n(111)x(111) > (110) > (111). Distinct states for hydrogen at steps versus hydrogen on terraces could be distinguished. The (110) surface is shown to be a (111) vicinal, probably the [3(111) x 2(111)] microfacetted surface. The zero coverage heat of adsorption on the well-ordered (111) surface (48 kJ/mol) in solutions is the same as the value reported by Ertl and co-workers for adsorption on a (111) surface in vacuum. Adsorption Isotherms for hydrogen on the (111) and (100) surfaces is adequately fit by the classical model for immobile adsorption at single sites with nearest neighbor repulsive interaction.
Date: April 1, 1980
Creator: Ross, Philip N., Jr.
Partner: UNT Libraries Government Documents Department

Plastic Finite Element Analysis of D0 Toroid Iron Welds

Description: The assembly of the DO toroid iron involves the use of large groove welds to connect massive blocks of steel. These welds are very heavily constrained, and large thermal strains develop which have produced large cracks in the base metal near the weld. The effort to solve these problems has involved investigations of weld geometry, weld preparation, and the metallurgy of both the base metal and the welding rod. The purpose of this analysis was to compare the effects of two welding rods with markedly different yield strengths and post-yieding behaviour on the plastic strains developed in the base metal near the weld.
Date: November 23, 1987
Creator: Wands, R.
Partner: UNT Libraries Government Documents Department

Development of computer simulations for landfill methane recovery

Description: Two- and three-dimensional finite-difference computer programs simulating methane recovery systems in landfills have been developed. These computer programs model multicomponent combined pressure and diffusional flow in porous media. Each program and the processes it models are described in this report. Examples of the capabilities of each program are also presented. The two-dimensional program was used to simulate methane recovery systems in a cylindrically shaped landfill. The effects of various pump locations, geometries, and extraction rates were determined. The three-dimensional program was used to model the Puente Hills landfill, a field test site in southern California. The biochemical and microbiological details of methane generation in landfills are also given. Effects of environmental factors, such as moisture, oxygen, temperature, and nutrients on methane generation are discussed and an analytical representation of the gas generation rate is developed.
Date: December 1, 1981
Creator: Massmann, J.W.; Moore, C.A. & Sykes, R.M.
Partner: UNT Libraries Government Documents Department

2D accelerator design for SITEX negative ion source

Description: Solving the Poisson-Vlasov equations where the magnetic field, B, is assumed constant, we optimize the optical system of a SITEX negative ion source in infinite slot geometry. Algorithms designed to solve the above equations were modified to include the curved emitter boundary data appropriate to a negative ion source. Other configurations relevant to negative ion sources are examined.
Date: January 1, 1983
Creator: Whealton, J.H.; Raridon, R.J.; McGaffey, R.W.; McCollough, D.H.; Stirling, W.L. & Dagenhart, W.K.
Partner: UNT Libraries Government Documents Department

Magnetic coordinates for equilibria with a continuous symmetry

Description: Magnetic coordinates for hydromagnetic equilibria are defined which treat toroidal and straight helical plasmas equivalently yet exploit the existence of a continuous symmetry to derive relations between various geometrical and physical quantities. This allows the number of equilibrium quantities which must be known to be reduced to a minimal, or primitive set. Practical formulae for various quantities required in hydromagnetic stability calculations (interchange, ballooning, and global) are given in terms of this primitive set.
Date: August 1, 1983
Creator: Dewar, R.L.; Monticello, D.A. & Sy, W.N.C.
Partner: UNT Libraries Government Documents Department

Influence of geometry on natural convection in buildings

Description: Strong free convection airflows occur within passive solar buildings resulting from elevated temperatures of surfaces irradiated by solar energy compared with the cooler surfaces not receiving radiation. The geometry of a building has a large influence on the directions and magnitudes of natural airflows, and thus heat transfer between zones. This investigation has utilized a variety of reduced-scale building configurations to study the effects of geometry on natural convection heat transfer. Similarity between the reduced-scale model and a full-scale passive solar building is achieved by having similar geometries and by replacing air with Freon-12 gas as the model's working fluid. Filling the model with Freon-12 gas results in similarity in Prandtl numbers and Rayleigh numbers based on temperature differences in the range from 10/sup 9/ to 10/sup 11/. Results from four geometries are described with an emphasis placed on the effects of heat loss on zone temperature stratification shifts.
Date: January 1, 1985
Creator: White, M.D.; Winn, C.B.; Jones, G.F. & Balcomb, J.D.
Partner: UNT Libraries Government Documents Department

High resolution seismic survey of the Hanna, Wyoming underground coal gasification area

Description: In November 1980 a high resolution seismic survey was conducted at the Department of Energy, Laramie Energy Technology Center's underground coal gasification test site near Hanna, Wyoming. The objectives of the survey were to determine the feasibility of utilizing high resolution seismic technology to locate and characterize underground coal burn zones and to identify shallow geologic faults at the test site. Seismic data acquisition and processing parameters were specifically designed to emphasize reflections at the shallow, 61 to 91 meter (200 to 300 foot) depths of interest. A three-dimensional grid of data was obtained over the Hanna II, Phases 2 and 3 burn zone. Processing included time varying filters, deconvolution, trace composition, and two-dimensional, areal stacking of the data in order to identify burn zone anomalies. An anomaly was clearly discernable resulting from the rubble-collapse void above the burn zone which was studied in detail and compared to synthetic models. It is felt, based on these results, that the seismic method can be used to define similar burns if great care is taken in both acquisition and processing phases of an investigation. The fault studies disclosed faults at the test site of hitherto unsuspected complexity. The fault system was found to be a graben complex with numerous antithetic faults. The antithetic faults also contain folded beds. One of the faults discovered may be responsible for the unexpected problems experienced in some of the early in-situ gasification tests at the site. A series of anomalies were discovered on the northeast end of one of the seismic lines, and these reflections have been identified as adits from the old Hanna No. 1 Coal Mine.
Date: January 1, 1982
Creator: Youngberg, A.D.; Berkman, E. & Orange, A.
Partner: UNT Libraries Government Documents Department

Influence of heat transfer modes on the scale-up of solvent pool burning in controlled-air incinerators. [Pan]

Description: An analytical modes of pool burning in a controlled-air incinerator was developed. Incinerator performance predicted by the model compared favorably with laboratory-scale incineration experiments. The model was extended to a full-scale incinerator, using results from an intermediate pilot-scale incinerator. The full-scale results showed the influence of various modes of heat transfer, and the importance of flame emissivity and incinerator wall temperature in controlling the burning rate. The influence of pan geometry on consumption rate was also evaluated for the full-scale incinerator.
Date: January 1, 1982
Creator: Gandhi, P.D. & Orloff, D.I.
Partner: UNT Libraries Government Documents Department

Discussion of enhancement in condensers

Description: A brief discussion of Professor Ralph L. Webb's paper, The Use of Enhanced Surface Geometries in Condensers, is given with emphasis on the importance of overall cost optimization in the application of heat transfer enhancement. A review of ORNL condensation experiments with enhanced surfaces is presented. The work has centered on optimizing the design variables associated with fluted surfaces on vertical tubes and comparing the tube performance with available enhanced tubes either for vertical or horizontal operation. Data with seven fluids including a hydrocarbon, fluorocarbons, and ammonia condensing on up to 30 different tubes have been obtained. The primary conclusion from this work is that fluted tubes can provide an enhancement in condensation coefficient of a factor of 6 over smooth vertical tubes and a factor of 2 over enhanced commercial tubes either operating vertically or horizontally. These data, together with field test data, have formed the basis for designing a prototype condenser for the 500 kWe East Mesa, California, direct-contact geothermal demonstration plant.
Date: January 1, 1980
Creator: Michel, J.W.
Partner: UNT Libraries Government Documents Department

Condenser designs for binary power cycles

Description: For the past four years, work has been in progress at ORNL to develop improved condensers for geothermal binary power cycles. The work has centered on optimizing the design variables associated with fluted surfaces on vertical tubes and comparing the tube performance with available enhanced tubes either for vertical or horizontal operation. Data with seven fluids including a hydrocarbon, fluorocarbons, and ammonia condensing on up to 30 different tubes have been obtained. Data for tubes of different effective lengths (0.15 to 1.20 m) and inclination have also been obtained. The primary conclusion from this work is that fluted tubes can provide an enhancement in condensation coefficient of a factor of 6 over smooth vertical tubes and a factor of 2 over enhanced commercial tubes either operating vertically or horizontally. These data, together with field test data, have formed the basis for designing two prototype condensers, one for the 60 kWe Raft River, Idaho, pilot plant and one for the 500 kWe East Mesa, California, direct-contact demonstration plant.
Date: January 1, 1980
Creator: Michel, J.W. & Murphy, R.W.
Partner: UNT Libraries Government Documents Department

Spin spectrometer at the holified heavy-ion research facility and some planned experiments

Description: The 4..pi.. multidetector ..gamma..-ray spectrometer at the Holified Heavy-ion Research Facility (HHIRF) is described in some detail. The following important features of this spectrometer are discussed: (a) the geometric arrangement, (b) the actual performance of the individual detector elements, (c) the associated electronics and data acquisition system, and (d) the response of the system to input ..gamma..-cascades including the effect of crystal-to-crystal scattering and the response to neutrons. The first few experiments to be performed are briefly described.
Date: January 1, 1980
Creator: Sarantites, D.G.; Jaaskelainen, M.; Hood, J.T.; Woodward, R.; Barker, J.H.; Hensley, D.C. et al.
Partner: UNT Libraries Government Documents Department

Computations of VSWR and mode conversion for complex gyrotron window geometries

Description: A computational method is described for determining VSWR and mode conversion for complex gyrotron window geometries. Assuming symmetric TE/sub on/ modes propagating in a circular cross-section guide, containing the window, one can write the total solution to the wave equation as the sum of the incident wave plus a wave scattered from the dielectric window region. The equations can be reformulated in terms of the scattered wave, resulting in a Helmholtz wave equation with an inhomogeneous driving term corresponding to the polarization current of the dielectric. Solutions are obtained using a suitable modification of the wave equation solver OPNCAV, and reflection coefficients, VSWR's and mode conversion information are then derived from an analysis of the reflected and transmitted powers. VSWR computations for typical single- and double-disk windows agree with conventional impedance calculations to within about 1%. Results for more complicated curved-boundary windows which cannot be treated by the standard methods are discussed.
Date: January 1, 1984
Creator: Salop, A. & Caplan, M.
Partner: UNT Libraries Government Documents Department

Fractal geometry of two-dimensional fracture networks at Yucca Mountain, southwestern Nevada: proceedings

Description: Fracture traces exposed on three 214- to 260-m{sup 2} pavements in the same Miocene ash-flow tuff at Yucca Mountain, southwestern Nevada, have been mapped at a scale of 1:50. The maps are two-dimensional sections through the three-dimensional network of strata-bound fractures. All fractures with trace lengths greater than 0.20 m were mapped. The distribution of fracture-trace lengths is log-normal. The fractures do not exhibit well-defined sets based on orientation. Since fractal characterization of such complex fracture-trace networks may prove useful for modeling fracture flow and mechanical responses of fractured rock, an analysis of each of the three maps was done to test whether such networks are fractal. These networks proved to be fractal and the fractal dimensions (D) are tightly clustered (1.12, 1.14, 1.16) for three laterally separated pavements, even though visually the fracture networks appear quite different. The fractal analysis also indicates that the network patterns are scale independent over two orders of magnitude for trace lengths ranging from 0.20 to 25 m. 7 refs., 7 figs.
Date: December 31, 1985
Creator: Barton, C.C. & Larsen, E.
Partner: UNT Libraries Government Documents Department