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Effect of multiple and delayed jet impact and penetration on concrete target borehole diameter

Description: The effect of multiple and delayed jet impact and penetration on the borehole diameter in concrete targets is discussed in this paper. A first-order principle of shaped-charge jet penetration is that target hole volume is proportional to the energy deposited in the target by the jet. This principle is the basis for the relation that target borehole diameter at any depth along the penetration path is proportional to the jet energy deposited in the target at that location. Our current research sh… more
Date: January 26, 2001
Creator: Murphy, M J; Baum, D W; Kuklo, R M & Simonson, S C
Partner: UNT Libraries Government Documents Department
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Developing improved relationships between microstructure and creep and shrinkage of cement-based materials. Final report for the period September 9, 1998 - July 31, 2000

Description: The shrinkage of concrete that occurs on drying is a complex function of age of concrete, rate of drying, temperature, and composition of concrete. This project investigated the fundamental relationships between microstructure and shrinkage. In order to accomplish this goal a new quantitative image analysis technique was developed to analyze the distribution of strain throughout the microstructure during drying. The technique has been verified at NIST and the results have provided new insights.… more
Date: January 1, 2001
Creator: Jennings, Hamlin M.
Partner: UNT Libraries Government Documents Department
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Design Review Report for Concrete Cover Block Replaced by Steel Plate

Description: The design for the steel cover plates to replace concrete cover blocks for U-109 was reviewed and approved in a design review meeting. The design for steel plates to replace concrete blocks were reviewed and approved by comparison and similarity with U-109 for the following additional pits: 241-U-105. 241-I-103, 241-Ax-101. 241-A-101, 241-SX-105, 241-S-A, 241-S-C, 241-SX-A.
Date: July 27, 2000
Creator: JAKA, O.M.
Partner: UNT Libraries Government Documents Department
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Geochemical Methods for the Identification of ASR Gel

Description: This paper presents a geochemical method for staining various products of the alkali-silica reaction. The method is based on both the composition of ASR gel and one of its properties (the ability to exchange cations with a fluid). The stained concrete can be observed in normal light and serves as both a rapid field screening method and a useful aid for detailed petrographic examinations.
Date: July 1, 1998
Creator: Guthrie, G. D. & Carey, J. W.
Partner: UNT Libraries Government Documents Department
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Analysis of Potential Concerete Floor Decontamination Technologies

Description: During the decontamination and decommissioning (D&D) activities to be conducted at the Femald Environmental Management Project (FEMP), contaminated concrete waste will be generated from the D&D of approximately 200 buildings and other structures [1]. The U.S. Department of Energy (DOE) owns the Fernald site. The site is a contractor-operated federal facility that produced high-purity uranium metal products for the DOE and its predecessor agency, the Atomic Energy Commission, from 1952 to 1989. … more
Date: August 6, 1997
Creator: Ebadian, M. A.
Partner: UNT Libraries Government Documents Department
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Spall Strength Measurements of Concrete for Varying Aggregate Sizes

Description: Controlled impact experiments have been performed to determine the spall strength of four different concrete compositions. The four concrete compositions are identified as, `SAC-5, CSPC', ("3/4") large, and ("3/8") small, Aggregate. They differ primarily in aggregate size but with average densities varying by less than five percent. Wave profiles from sixteen experiments, with shock amplitudes of 0.07 to 0.55 GPa, concentrate primarily within the elastic regime. Free-surface particle velocity m… more
Date: May 5, 1999
Creator: Chhabildas, Lalit C.; Kipp, Marlin E.; Reinhart, William D. & Wilson, Leonard T.
Partner: UNT Libraries Government Documents Department
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The structural failure probability analysis of pipe impact onto a concrete wall.

Description: The purpose of this study was to perform a probabilistic safety assessment of a steel pipe impacting against a concrete wall. The probabilistic structural integrity evaluation was coupled with a deterministic FE program, NEPTUNE. This evaluation included deterministic modeling, definition of random variables, description of failure criterion or limit state function, running the probabilistic analysis and reviewing the final results.
Date: May 15, 2002
Creator: Kulak, R.; Merchertas, P. & Petkevicius, K.
Partner: UNT Libraries Government Documents Department
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NEW NONLINEAR ACOUSTIC TECHNIQUES FOR NDE

Description: Acoustic nonlinearity in a medium may occur as a result of a variety of mechanisms. Some of the more common nonlinear effects may come from: (1) one or several cracks, volumetrically distributed due to age or fatigue or single disbonds or delamination; (2) imperfect grain-to-grain contacts, e.g., materials like concretes that are cemented together and have less than perfect bonds; (3) hard parts in a soft matrix, e.g., extreme duty materials like tungsten/copper alloys; or (4) atomic-scale nonl… more
Date: September 1, 2000
Creator: TENCATE, J. A.
Partner: UNT Libraries Government Documents Department
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RADIATION LEVELS IN THE VICINITY OF THE PURIFICATION DEMINERALIZERS. CORE 1, SEED 1. Test Results T-641306

Description: BS>A test was performed to determine the activity build-up inside the 1AC and 1BD purification demineralizer concrete enclosure. A maximum radiation level of 1100 mr/hr was detected inside the 1AC demineralizer enclosure at a point 10.0 ft from the top. The maximum radiation level inside the 1BD enclosure was 700 mr/hr at a point 9.5 ft below the top. An analysis of data from five tests indicates that the extent of the activity build-up, as well as the level of activity, is definitely increasin… more
Date: October 10, 1960
Partner: UNT Libraries Government Documents Department
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Numerical simulation of damage and fracture in concrete from shaped charge jets

Description: This paper addresses numerical simulation of damage and fracture in concrete from the impact and penetration of shaped charge jets. We have modeled the jet penetration process with CALE, a two dimensional arbitrary Lagrange Eulerian hydrocode. We have looked at several constitutive models ranging from simple pressure dependent yield to more complex deviatoric models that include the effects of dilatency. Evaluation of the concrete material models is based on comparison to experimental results o… more
Date: September 13, 2000
Creator: Murphy, M J; Baum, D W; Clark, D B; McGuire, E M & Simonson, S C
Partner: UNT Libraries Government Documents Department
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PERIODIC RADIATION SURVEY. CORE I, SEED 1. Section 3. Test Results T- 612394

Description: Radiation levels inside the concrete enclosures but outside the reactor plant containers after shutdown were determined. Radiation levels in the 1AC, 1BC boiler chamber enclosures and in the reactor chamber enclosure were on the average higher than in previous tests. The highest reading obtained was 7.5 mr/ hr and the lowest reading was 0.03 mr/hr; the mean level was 3.76 mr/hr as compared to 1.37 mr/hr in previous tests. (W.L.H.)
Date: June 17, 1960
Partner: UNT Libraries Government Documents Department
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UCom: Ultra-wideband Communications in Harsh Propagation Environments

Description: LLNL has developed an ultra-wideband (UWB) system that provides unique, through-the-wall wireless communications in heavy metallic and heavy concrete indoor channels. LLNL's UWB system is the only available wireless communications system that performs successfully and reliably in facilities where conventional narrowband communications usually fail due to destructive reflections from multiple surfaces. These environments include: cargo ships and reinforced, heavy concrete buildings. LLNL's revol… more
Date: March 14, 2007
Creator: Nekoogar, Faranak
Partner: UNT Libraries Government Documents Department
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Hydrothermal alteration of cementitious materials, Part II: second and third batch of samples

Description: This report describes experiments designed to provide data for a quick engineering assessment of the microstructural, mineralogical, and mechanical changes in hydrothermally altered concrete and changes in associated water chemistry.
Date: October 25, 1997
Creator: Meike, A. & Myers, K. B. L.
Partner: UNT Libraries Government Documents Department
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Elastic shock response and spall strength of concrete

Description: Impact experiments have been performed to obtain shock compression, release response, and spall strength of two scaled concrete formulations. Wave profiles from a suite of ten experiments, with shock amplitudes of 0.08 to 0.55 GPa, focus primarily on the elastic regime. Despite considerable wave structure that develops at the shock transits these heterogeneous targets, consistent pullback signals were identified in the release profiles, indicating a spall strength of about 30 MPa. Explicit mode… more
Date: August 1, 1997
Creator: Kipp, Marlin E.; Chhabildas, Lalit C. & Reinhart, William D.
Partner: UNT Libraries Government Documents Department
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Electrokinetic decontamination of concrete. Final report, August 3, 1993--September 15, 1996

Description: The ELECTROSORB{reg_sign} {open_quotes}C{close_quotes} process is an electrokinetic process for decontaminating concrete. ELECTROSORB{reg_sign} {open_quotes}C{close_quotes} uses a carpet-like extraction pad which is placed on the contaminated concrete surface. An electrolyte solution is circulated from a supporting module. This module keeps the electrolyte solution clean. The work is advancing through the engineering development stage with steady progress toward a full scale demonstration unit … more
Date: December 31, 1998
Partner: UNT Libraries Government Documents Department
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Phase 3 Final Topical Report for the Remote Operated Vehicle with C02 Blasting (ROVCO2)

Description: This report documents the third and final phase of the Remote Operated Vehicle with CO2 Blasting (ROVCO2) Program. The Program=s goal is to develop and demonstrate a tool to improve the productivity of concrete floor decontamination. In Phase 3 of the ROVCO2 program, the workhead and the COYOTEE end-effector were redesigned, and effectiveness and productivity tests were performed. This report documents the development activities. The results show that the ROVCO2 system is an efficient decontami… more
Date: April 14, 1998
Partner: UNT Libraries Government Documents Department
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