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This report presents results of the numerical simulation of a U.S. Naval turboprop test cell facility. The ultimate purpose of this simulation was to provide the Navy with a numerical model to be used for the evaluation of the aerothermal performance of test cells. This simulation was performed using the structured finite volume (SFV) computer code. A description of the physical model, mathematical details, boundary conditions, and results of the study are presented and covered in Volume 1. Volume 2, Code Documentation and Listings, provides a copy of the input files developed for the modeling of turboprop test cells.... Computational fluid dynamics, Test cells, Aviation test facilities, Original Contains Color Plates: All DTIC/NTIS Productions will be in Black and White.

File characteristics: Software (8 files). Physical description: 1 computer diskette; 5 1/4 in.; high density; 1.2MB. System requirements: IBM-PC compatible; MS-DOS 3.1 or higher; DOS copy. SAP IV is a general purpose finite element analysis program for linear structural analysis. The program can analyze structures that are subject to either static or dynamic loads. The structures can be described in terms of truss, frame, plate, shell, or brick elements or combinations of elements. The static loads include concentrated loading applied to discrete points on the structural models; and loads, concentrated loading applied to discrete points on the structural models; and loads, concentrated or uniform, applied to individual elements in the model. The loads can be combined into load cases. The dynamic analysis features include modal analysis to obtain mode shapes and frequencies, response history analysis using either modal superposition or direct integration techniques, and response spectrum analysis., Includes User's Guide, AD-A266 907.

NCEL examined the Impact Load Method (ILM) to elicit a response from bridges and piers as a means of structural assessment. Stiffness changes were detected that were correlated to loss of structural function from material damage and deterioration. Parametric studies were performed on a one-third scale model pier and a highway bridge using finite element modeling that was verified by ILM tests. Studies showed that the ILM is sensitive to the loss of cross section in pier and bridge decks and well as to the loss of pile support.... Impact load method, Finite element method, Bridges, Piers, Reinforced concrete.

The Naval Civil Engineering Laboratory (NCEL) has developed a prototype horizontal drilling system (HDS) that is designed to reach distances of 10,000 to 15,000 feet and should be capable of reaching 25,000 feet in favorable conditions. This system uses high pressure water (15,000 psi) to 'drill' at rates of 10 to 30 in./min. Steering is accomplished by instructing the drillhead (nozzle) to cut in an eccentric pattern. As part of a complete cable protection system, NCEL has also developed a technique for divers to adapt the seaward end of the drill pipe to a section of flexible pipe and a procedure for pigging multiple cables through the installed pipe assembly from shore or from sea. This allows easy interface between the installed shore cable section and the large cable ships that are used for deep water cable installation and deployment. Laboratory and limited field tests of the HDS system have been conducted and results agree with theory for the distance tested (500 feet). Negotiations are in progress to transfer the technology to private industry and continue the development. Cable survivability, Cable protection, Cable shore landings, Ice scour, Horizontal drilling, Waterjet cutting, Well logging, Pipe joints

This report was prepared as part of the Navy's Seismic Hazard Mitigation Program. The Navy has numerous bases located in seismically active regions throughout the world. Safe effective design of waterfront structures requires determining expected earthquake ground motion. The Navy's problem is further complicated by the presence of soft saturated marginal soils that can significantly amplify the levels of seismic shaking as evidenced in the 1989 Loma Prieta earthquake. The Naval Facilities Engineering Command's seismic design manual, NAVFAC P355.1, requires a probabilistic assessment of ground motion for design of essential structures. This report presents the basis for the Navy's Seismic Hazard Analysis procedure that was developed and is intended to be used with the Seismic Hazard Analysis computer program and user's manual. This report also presents data on geology and seismology to establish the background for the seismic hazard model developed. The procedure uses the historical epicenter data base and available geologic data, together with source models, recurrence models, and attenuation relationships to compute the probability distribution of site acceleration and an appropriate spectra. This report discusses the developed stochastic model for seismic hazard evaluation and the associated research.... Earthquake, Ground motion, Seismic hazard analysis, Acceleration.

An automated procedure has been developed to perform seismic analysis using available historic and geologic data. The objective of the seismicity study is to determine the probability of occurrence of ground motion at the site. Response spectra and time history techniques are presented.... Earthquake, Seismic, Response spectra, Time history, Site acceleration.

A diver-operated lift system has been developed for underwater construction divers. The system consists of three different open-bottom lift bags with the following lift ranges: 200 to 550 pounds, 500 to 1,250 pounds, and 1,000 to 3,000 pounds. The system maintains a constant buoyancy during ascent by venting the expanding air volume out under the slider of a zipper, which is attached to the side of the bag along the vertical direction. A diver-operated air wand is used to compensate for compression of the air volume during descent. The system is easy to maintain, and most repairs can be performed by the users in the field. This report documents the development, test, and evaluation of the engineering model systems. Lift system, Open-bottom lift bags, Dump valve, Air- filled valve, Air-filled wand

The objective of this work is the demonstration of feasibility of computerized optimal tuning of electronic motion controllers for mobile heavy equipment end-effectors. A backhoe yaw mode position control system was selected as the application for the purpose of proof of concept. The control algorithm selected for use in the servocontroller is Pseudo-Derivative Feedback (PDF). A computer model and an operational laboratory model of a translational electrohydraulic position control system dynamically analogous to the structural, mechanical, and hydraulic components of the selected backhoe position control system were constructed. These models were exercised in simulation of the backhoe system equipped with an electronic servocontroller incorporating the PDF algorithm. The computer model was first validated in its baseline configuration by way of comparison with baseline laboratory model test results. 'Baseline' refers to the complete system, but with proportional position feedback control in place of the PDF algorithm. An interesting aspect of this project is the two degree-of-freedom system constituted by the relatively compliant boom, coupling the hydraulic actuator with a fully loaded bucket. This is of particular interest since the bucket does not lend itself to position instrumentation, thereby precluding load position feedback. Data supporting the successful demonstration of computerized automation of optimal tuning is presented.... Motion control, Computer-aided control system design

An investigation was completed on the effects of high operational temperatures on a Navy firefighting training facility at the Naval Training Center, Mayport, Florida. Concrete temperature measurements were made during a simulated maximum use training cycle, core samples were retrieved and examined, and predictions of concrete thermal performance were made with a finite element model. It was concluded that the concrete had not deteriorated and should perform well for years of additional service. Refractory linings are not required for new facilities if these facilities are constructed of heat resistant, high strength lightweight concrete and the walls and ceiling near the fire source are protected by a continuous steel plate barrier.

This study explores the significance of second-order wave excitations on a large pontoon and tests the feasibility of reducing a nonlinear free surface problem by perturbation expansions. A simulation model has been developed based on the perturbation expansion technique to estimate the wave forces. The model uses a versatile finite element procedure for the solution of the reduced linear boundary value problems. This procedure achieves a fair compromise between computation costs and physical details by using a combination of 2D and 3D elements. A simple hydraulic model test was conducted to observe the wave forces imposed on a rectangle box by Cnoidal waves in shallow water. The test measurements are consistent with the numerical predictions by the simulation model. This result shows favorable support to the perturbation approach for estimating the nonlinear wave forces on shallow draft vessels. However, more sophisticated model tests are required for a full justification. Both theoretical and experimental results show profound second-order forces that could substantially impact the design of ocean facilities.

SAP IV is a general purpose finite element analysis program for linear structural analysis. The program can analyze structures that are subject to either static or dynamic loads. The structures can be described in terms of truss, frame, plate, shell, or brick elements or combinations of elements. The static loads include concentrated loading applied to discrete points on the structural models; and loads, concentrated loading applied to discrete points on the structural models; and loads, concentrated or uniform, applied to individual elements in the model. The loads can be combined into load cases. The dynamic analysis features include modal analysis to obtain mode shapes and frequencies, response history analysis using either modal superposition or direct integration techniques, and response spectrum analysis. Structural analysis, Finite element analysis, Modal analysis, Response spectra analysis, Time, History analysis, Static structural analysis, Dynamic structural analysis, Also included with AD-M000263.

Data were collected at four U.S. Navy and Marine Corps bases to evaluate bioventing technology efficacy in removing low-volatility fuels from subsurface soils and the groundwater table. These sites have soil contamination attributed to spills or leaks of fuels having low vapor pressures and very low water solubilities, such as JP-5 jet fuel, diesel fuel, #6 fuel oil (bunker fuel), waste oil, and lubricants. The major contaminant studied is JP-5 jet fuel, a kerosene distillate fraction similar to commercial jet fuel A., Prepaed in collaboration with Battelle, Columbus,OH and Washington State University (Dept. of Civil and Environmental Engineering), Pullman, WA.

This report presents three conceptual methods for connecting barge- like modules in open seas. The goal is to identify new technology and materials for use in the development of a high strength connecting system that can be installed fast in open seas with limited heavy lift equipment. The three concepts presented are: flat, flexible connector with pneumatic bladders, cylindrical, flexible connector with pneumatic bladders, and flat, flexible connector with a mechanical closure. Major components of each concept are described to demonstrate the mechanism of the concept. Preliminary calculations are provided to show the strength and holding capacity. The advantages and disadvantages of each concept are discussed. Research and development requirement for each concept are discussed. Research and development requirement for each concept are identified. A test procedure to verify the feasibility of the concepts is also proposed.... Modular connector, Conceptual study, Open seaways, Flat, Flexible connector, Cylindrical, Flexible connector, Pneumatic bladders., Prepared in collaboration with American Management Systems, Inc. Chesapeake, VA.

Water, placed in the near proximity of a confined explosion, can mitigate the gas pressure loading developed inside a structure confining an explosion. This phenomenon can be exploited in the design and operation of new and existing facilities exposed to a potential internal explosion. This water concept offers the potential for major savings in the cost for explosives safety of ordnance facilities from accidental explosions, for survivability of combat facilities from enemy weapons, and for physical security of sensitive facilities from terrorist bombings. This paper describes the mechanism by which water absorbs energy from a confined explosion and how this phenomenon reduces the gas pressure loading from a confined explosion; presents test data demonstrating that water can indeed mitigate the gas pressure loading from a confined explosion; describes how water could be exploited in the design of facilities impacted by confined explosions, and estimates the benefits derived from water, in terms of the reduction in land area encumbered by hazardous debris from unhardened ordnance facilitates, reduction in the cost of structures designed to fully or partially contain the effects from an internal explosion, and the increase in the safe explosive limit for existing ordnance facilities., See also ADA261116. Presented at Minutes of the Explosives Safety Seminar (25th) held in Anaheim, CA on 18-20 August 1992. Published in Minutes of the Explosives Safety Seminar (25th), v4 p311-339, Aug 1992.

The Naval Civil Engineering Laboratory is developing a new magazine concept that will reduce the land area encumbered by ESQD arcs and improve the efficiency of weapons handling operations. This new High Performance Magazine (HP Magazine) can reduce encumbered land by 80% and significantly reduce operational costs. The most important factor in the improved performance of the HP Magazine is the reduction of the Maximum Credible Event (MCE) to the Net Explosive Weight (NEW) of High Explosive (HE) in an individual storage cell. Internal cell walls are being developed to mitigate the effects of an explosion in any cell and prevent sympathetic detonation in adjacent cells. The performance of the HP magazine also is enhanced by soil cover and tunnel type exits that reduce the safe distance for debris and overpressure. The MCE in a magazine storing conventional palletized weapons (e.g. bombs, projectiles, mines) would be reduced from about 200,000 lbs to about 10,000 lbs. The MCE for missile storage would be reduced from 100,000 lbs to 10,000 lbs. The preliminary HP Magazine concept and its key components are shown in Figure 1., See also ADA260984, Volume I. Published in the Minutes of the Explosives Safety Seminar (25th) held in Anaheim, CA on 18-20 August 1992 (p373-402).

The loads incident on Mk82 acceptors located two feet from the acceptor side of an intervening 3.5 foot sand wall were evaluated with the aid of hydrocodes, literature, and closed form solutions. The donor side of the sand wall was subject to the simultaneous detonation of a 4 by 6 array of 24 Mk82 donors. The leading edge of the donor array was located at a two foot standoff from the sand wall. The problem was divided into three regimes: (1) the loads promoted on the sand wall from simultaneous detonation of the donors, (2) the response of the barrier and propagation of the donor loads through the sand wall, and, (3) the interaction of the sand wall barrier with the acceptors. The extent to which the loads promoted by the donor couple to the intervening sand wall are greatly affected by the stacking configuration of the donors. This is due to the occurrence of jetting, which occurs between adjacent rows of donors and the existence of rarefied regions that occur between adjacent donor columns. The jetting results in local regions of the wall being subject to very intense pressure distributions. The rarefied regions occurring between donor columns last several hundred microseconds and thwart propagation of loads toward the wall from adjacent columns of donors. The sand wall attenuates high frequency components of the incident wave but is relatively ineffective in attenuating the low frequencies which are the major components of the incident wave. The wall becomes rapidly fluidized and the loads incident on the acceptor are to a large extent governed by the fluid-structure interaction between the multi-phase flow from the barrier debris and the stress wave response of the acceptor., See also ADA260984, Volume I. Published in the Minutes of the Explosives Safety Seminar (25th) held in Anaheim, CA on 18-20 August 1992 (p453-466).

Two widely available general purpose computer programs for three-dimensional nonlinear dynamic finite element analysis were applied to three types of reinforced concrete structures of recent interest to Navy explosive safety: a novel cylindrical missile test cell concept, flat slabs with variable shear steel, and a soil-covered roof slab for a new high performance magazine concept. Results from codified single-degree-of-freedom (SDOF) methods for design of explosive safety structures were considered and compared with finite element technology. An overview of these baseline studies is presented. A commercial implicit finite element program was used to analyze the cylindrical missile test cell. Three-dimensional model construction, nonlinear concrete material modeling, and dynamic response were emphasized. Support for embedded reinforcement modeling was found to be very useful in construction of the model so as to retain the inherent anisotropic behavior of the composite structure. Concrete material modeling capability was highly sophisticated, but problematical in application when substantial cracking accumulated in the dynamic response. Sufficient results were nonetheless obtained to demonstrate the value of computational structural dynamics technology in providing detailed understanding of the behavior of complex explosive safety designs, ~ An explicit finite element program was used to analyze the dynamic response of two flat slabs subjected to conventional blast pressure levels., See also ADA261116, Volume IV. Presented at the Department of Defense Explosives Safety Seminar (25th) held in Anaheim, CA on 18-20 August 1992. Published in the Proceedings of the Department of Defense Explosives Safety Seminar (25th), p133-159, 1992.

The High Performance (HP) Magazine concept consists of an earth-covered box structure with interior cells where munitions are stored. The cells are designed to prevent sympathetic detonation between cells, thereby limiting the Maximum Credible Event (MCE) to the Net Explosive Weight (NEW) stored in any cell. The reinforced concrete box structure and soil cover and designed to limit the safe distance for the MCE from blast, fragment, and debris outside the magazine. Small-scale (1/10) feasibility tests were conducted by the Terminal Effects Research & Analysis (TERA) Group at Socorro, NM in 1991. Results from these tests will be used to demonstrate the feasibility of the HP Magazine roof and soil cover to mitigate external debris and pressure hazards. A reusable magazine test fixture was built and six tests were performed in which 2.4 in. thick reinforced concrete roof specimens were covered with 0, 3.6, and 7.2 in. of soil. The explosive test charges were 7.43-lb rectangular blocks of Composition C4 (equivalent to 10 lb of TNT). Data included airblast instrumentation, high-speed motion pictures, and debris recovery. The test results demonstrated the feasibility of the HP Magazine roof and soil cover to mitigate external debris and pressure hazards. For a full-scale 10,000-lb MCE, the safe ESQD (Explosive Safety Quantity Distance) pressure arc was reduced to about 500 ft (23.2 W (1/3)), the distance from the magazine that the peak pressure decays to 1.2 psi. The full-scale ESQD arcs for debris were reduced to about 800 ft (37.2 W (1/3)) and 550 ft (25.5 W (1/3)) for soil covers of 3 and 6 ft, respectively. This is much less than the NAVSEA OP-5 (Reference 1) ESQD arc for debris and fragment which is 1,250 ft., See also ADA260984. Presented at the Explosives Safety Seminar (25th) Held in Anaheim, CA on 18-20 August 1992. Published in the Explosives Safety Seminar Proceedings, v1 p331-371, August 1992.

The use of a high-pressure jet of cryogenic fluid (e.g., liquid nitrogen at -320 deg F) to remove paint and other protective coatings from Navy aircraft and ships was studied. The objective of the work was to explore the feasibility of developing a paint removal method that is less harmful to the environment than the chemical paint stripping methods presently in use. It was learned that only thick (t >0.020 inch) films of paint can be effectively removed by the mechanism of thermal shock. Aircraft paint is too thin and flexible to be removed by cryogenic methods. Cryogenic methods are not recommended for use on ships because of the danger of steel embrittlement by low temperatures. It was demonstrated that a jet of liquid nitrogen can effectively remove certain paints (regardless of thickness) by the mechanism of differential thermal contraction. The process may have application where control of paint waste is essential, for example, removal of thick films of lead base paint.

This report on the sodium nitrite wastewater treatment process discusses the results of 12 simulation runs and six test runs using the boiler hydroblasting wastewater from the Long Beach Naval Shipyard (LBNSY). Reproducible results were obtained showing the total destruction of sodium nitrite by sulfamic acid in Navy boiler hydroblasting wastewater. The removal of heavy metals was equally successful, an approach which resulted in reducing nearly all the ions to the discharge limits by EPA standards. The sludge contained 30 percent solids by weight and passed the TCLP test required for disposal. The estimated cost of treatment remains under $0.30 per gallon compared with the 1990 contract haul cost of $2.00 per gallon., Prepared in collaboration with California State Polytechnic Univ, Pomona, CA.

The Navy has 229 hazardous waste landfills that must be treated or capped. Treatment of these wastes is often complicated and expensive due to the wide range of contaminants present. Current technology does not meet the needs for remediating all 229 sites. An alternative to treatment is to design a long-term cover, or cap, for the landfill. Current EPA guidance allows for modifications which may reduce costs and increase life expectancy of a final cover system.

This report is part of the Navy's Earthquake Hazard Mitigation Program. It describes the effects of the Loma Prieta earthquake on Naval Station, Treasure Island focusing on geotechnical comparison of performance of marginal and improved sites. Procedures are presented to estimate settlements and results are compared to observed data. A detailed analysis of ground motion is presented in conjunction with site amplification. It is shown that the site amplification at Naval Station Treasure Island is caused by the stiff Bay Mud layer rather than the loose sand deposits. A comparison is made to the Mexico City earthquake of 1985, which also had high plasticity stiff clays. The high stiffness with shear strain exhibited by these deposits in comparison with normal clays is shown as a function of high plasticity and should be a warning to engineers of potential site amplification of ground motion from distant earthquakes.

This report presents the computation procedure that is used to produce load rating charts for cranes operating on platforms in the ocean environment. A rating charge defines the load that can be safely lifted for each boom angle in the boom operating range. The platform supporting the crane may be a fixed offshore platform or a ship or barge. During the crane operating cycle, loads will be lifted from or placed on a work boat or some other small vessel. The procedures utilizes the relative motion of the supporting platform and the vessel alongside to determine dynamic load factors. The dynamic load factors are applied to the land rating to derate the crane for marine operations. The computation procedure has been implemented in a computer program that is also discussed. Cranes, load rating, dynamic load rating, lift cranes, marine cranes, SAE J-1366

This extensive literature review covers all aspects of in situ and on-site bioremediation of gasoline, middle distillate fuels, and other refined petroleum products, using information available through 1988. Topics covered include: composition of different fuels, factors affecting biodegradation rates, responsible microorganisms, degradation pathways, factors enhancing biodegradation, and potential limitations. This report is in three volumes. Volume 1 covers general information of most interest to managers and non- specialists. Volume 2 contains technical information required for in-depth coverage. Volume 3 covers related information, including detailed applied information on screening and microbial enumberation methods, laboratory microoganisms studies, bioreclamation site preparation, bioreactor use and selection, cost data, and competing technologies. Bioremediation, in situ, fuels, on-site, biodegradation, literature review., See also Volume 3 AD-A252 681.

This extensive literature review covers all aspects of in situ and on-site bioremediation of gasoline, middle distillate fuels, and other refined petroleum products, using information available through 1988. Topics covered include: composition of different fuels, factors affecting biodegradation rates, responsible microorganisms, degradation pathways, factors enhancing biodegradation, and potential limitations. This report is in three volumes. Volume 1 covers general information of most interest to managers and non- specialists. Volume 2 contains technical information required for in-depth coverage. Volume 3 covers related information, including detailed applied information on screening and microbial enumberation methods, laboratory microorganism studies, bioreclamation site preparation, bioreactor use and selection, cost data, and competing technologies. Bioremediation, in situ, fuels, on-site, biodegradation, literature review., See also Volume 3 AD-A252 683.

This extensive literature review covers all aspects of in situ and on-site bioremediation of gasoline, middle distillate fuels, and other refined petroleum products, using information available through 1988. Topics covered include: composition of different fuels, factors affecting biodegradation rates, responsible microorganisms, degradation pathways, factors enhancing biodegradation, and potential limitations. This report is in three volumes. Volume 1 covers general information of most interest to managers and non- specialists. Volume 2 contains technical information required for in-depth coverage. Volume 3 covers related information, including detailed applied information on screening and microbial enumberation methods, laboratory microorganism studies, bioreclamation site preparation, bioreactor use and selection, cost data, and competing technologies. Bioremediation, in situ, fuels, on-site, biodegradation, literature review., See also Volume 2 AD-A252 682.

This is the final report for Annular Vortex Combustor (AVC) development for commercial applications. The work culminated in the successful demonstration of a 2-MB/H proof-of-concept (POC) model firing coal-water slurry fuel (CWF) and dry pulverized coals. This development was concerned with a new concept in combustion for which there was a general lack of relevant information. The work began with a cold flow modeling study and with the design and test of two subscale models (0. 15 and 0. 3 MB/H) and one full-scale model (3 MB/H) to obtain the needed information. With the experience gained, the 2-MB/H POC model was then designed and demonstrated. Although these models were designed somewhat different from one another, they all performed well and demonstrated the superiority of the concept. In summary, test results have shown that AVC can be fired on several coal fuels (CWF, dry ultrafine coal, utility grind pulverized coal) at high combustion efficiency (>99 percent), high firing intensity (up to 0.44 MB/H-ft3), and at temperatures sufficiently low for dry ash removal and in-situ pollution abatement. The combustion process is completed totally inside the combustor. Conventional combustion enhancement techniques such as preheating (air and/or fuel), precombustion, and post-combustion are not needed.

The explicit three-dimensional finite element computer program DYNA3D was applied to the problem of modeling penetration of anchor projectiles into seafloor rock media. It was used to computer the dynamic response and the residual stresses and strains for an axisymmetric penetration model where the penetrator axis and velocity vector are normal to the seafloor. Homogeneous nonlinear material behavior is considered for both the anchor projectile and the seafloor rock material, and a frictional interface is prescribed between the anchor projectile and rock media. An introductory discussion of cavity expansion theory is also included and used to guide physical interpretation of the data obtained from the numerical model. Validation of the three-dimensional model was limited to comparison with previous DYNA2D results for penetration depths. Qualitative agreement with very approximate analytical methods was also observed. A parameter study revealed that the rock target hardness, as represented by the strain hardening modulus in an elastic-plastic model of rock behavior, strongly influenced the confinement stress acting on the embedded projectile. Conversely, it was found that the coefficient of friction of the contact surface between the projectile and rock had only minor affect on the confinement stress, although it did affect the depth of penetration. DYNA3D is potentially a convenient and forthcoming framework for determining the relationship between confinement stress and various parameters of seafloor rock and anchor projectiles.

A test series was conducted at Edwards Air Force Base to determine noise and temperature environments that joint seal materials experience on an operational runway. Impingement of exhaust flow from jet engines creates an aerothermal environment for joint seal materials that contributes to, and accelerates, the deterioration and failure of joint seals. The aerothermal environment consists of noise (considered in this report as acoustically-induced as well as flow-induced fluctuations) and temperature. Current specifications for runway joint seal materials do not consider the effects of noise. The test data in this report show noise levels of 164 db at the joint seal surface. The conclusion is that the potential for energy transfer from exhaust flow noise is almost as high as the potential for energy transfer from exhaust flow temperature.

This report presents data from a full-scale, three-dimensional cable payout test and the corresponding numerical simulations using the SEADYN90 computer model. The experiment, which was conducted at the Atlantic Undersea Test and Evaluation Center (AUTEC), deployed 10 miles of 3/4-inch-diameter cable from a vessel that followed a predetermined course. Ship position, cable payout rate, and current profile were measured, along with 11 cable descent trajectories at predefined intervals along the cable. The measured data were then input into SEADYN90 with minimal simplifications to ensure that modeling errors could be distinguished from input errors. Qualitative and quantitative comparisons between the numerical and measured trajectories were considered excellent when a normal drag coefficient of 2.54 +-0.1 (typical of strumming) was used. The results demonstrate that SEADYN90 is capable of accuretly modeling realistically complex test scenarios with stochastic current profiles, ship velocities, and payout rates, and that the data set is complete and high quality.

To establish research requirements for development of modern, specialized software for computational structural dynamics in support of Navy explosive safety facilities, NCEL conducted baseline studies to assess commercial or currently available general purpose computer programs. Two widely available general purpose computer programs for three-dimensional nonlinear dynamic finite element analysis were applied to three types of reinforced concrete structures of interest to Navy explosive safety facility designers: (1) a novel cylindrical missile test cell concept, (2) flat slabs with variable shear steel, and (3) a soil-covered roof slab for a new high performance magazine concept. Results from codified single-degree-of-freedom (SDOF) methods for design of explosive safety structures were also considered and compared with finite element technology. This report provides an overview of these baseline studies.... Finite element modeling, Structural dynamics, Structural analysis, Missile test cells, Reinforced concrete modeling, Explosive safety facilities., Original contains color plates: All DTIC and NTIS reproductions will be in black and white.

Unleaded fuel has leaked from an underground storage tank and spread 100 M radially in the saturated and unsaturated zone under a clay cap of soil. The estimated amount of fuel spilled in the saturated zone is 10,000 L. Four bioreactors have been installed in the ground at the site, one dedicated to aerobic and three to separate anaerobic conditions: methanogenic, nitrate-reducing and sulfate-reducing. The bioreactors are stainless steel cylinders filled with contaminated zone soil and contain approximately 84 L. Contaminated groundwater is pumped through each bioreactor in an upward flow. Influent and effluent levels of the aromatic hydrocarbons benzene, toluene, ethylbenzene, 1,2,4- and l,3,5-trimethylbenzene, and m/o/p-xylene were examined. In addition, preliminary studies have suggested anaerobic degradation of these aromatic hydrocarbons, although the biochemical regime remains to be ascertained., Presented at the 18th Environmental Symposium and Exhibition of the American Defense Preparedness Association, February 24-27, 1992, Alexandria, VA. Prepared in cooperation with Stanford Univ. and Orange County Water District.

The subject tests provided the basis for evaluation of the potential benefits of application of stereo vision systems (SVS) to tough terrain extendable boom forklifts (EBFL) for the purpose of assisting the vehicle operator with cargo acquisition and placement. The SVS, a three-dimensional imaging system with a stereoscopic camera, includes a (stereo) video monitor located in the cab which provides the operator with an unimpeded three-dimensional view of the cargo and the vehicle's end-effector (e.g., fork tines). The tests focused on loading and unloading a 1,000-pound palletized cargo into and out of a 20-foot-long ISO container. Retrofit of an EBFL with an SVS was shown to be technically and economically feasible. Test data reduction, based on statistical analysis of the results, showed that use of the SVS can improve average productivity for a novice military operator by 17 percent. It is expected that with the eventual use of 40-foot-long ISO containers, the productivity improvement will he two or three times greater. Future efforts would evaluate the SVS application to 40-foot-long ISO containers, investigate cost and performance of miniaturized monitors, and consider provision of a wide-angle vision system. Material handling equipment, rough terrain forklifts, load/cargo acquisition.

The purpose of this effort was to assess the feasibility of developing a desiccant system to produce potable water from atmospheric sources that is compatible with military constraints. Goals were: (1) to examine desiccant technology, investigate methods of using available desiccants to collect atmospheric moisture, (2) develop a conceptual model of a desiccant water production system, and (3) develop a mathematical model to simulate the operation of the conceptual model. Results show that a desiccant system can produce large quantities of potable water using relatively small amounts of fuel for heat and fan power. The focus of this project was using a liquid desiccant (such as triethylene glycol) in an absorption-distillation cycle. This report documents the theoretical analysis of a hypothetical liquid desiccant based system for producing liquid water through collection of atmospheric moisture. Estimates are mode of cost, weight and water production rate for the hypothetical system.

A portable Hydraulic Power Source (PHPS) has been designed to enable the Naval Construction Divers to operate oil hydraulic tools in an Arctic environment. The PHPS is a three-piece assembly developed to be lightweight, mobile, and capable of powering hydraulic tools through a 250-foot hose. It can be handled manually by four personnel, transported in a small aircraft, and operated from a 22-foot inflatable boat. The PHPS can start at -40 F and supply 8 gpm of hydraulic fluid at 2,000 psi. This report describes the system, the approach used in developing the system, and the results of performance and reliability testing.

A set of three rugged divers' tools - rotary impact tool, a bandsaw, and a rotary disk tool - each powered by an interchangeable 3-horsepower seawater hydraulic motor, have been developed for the construction diver. The tools are supplied hydraulic power by a high-pressure seawater pump driven by a diesel engine. This pump provides filtered seawater at 14 gpm and 2,000 psi in an open circuit system. The objective for developing the Multi-Function Tool System (MFTS) was to provide Underwater Construction Teams (UCTs) with a tool system to meet their operational needs and operate safely without contaminating the environment. This MFTS is environmentally neutral, and the single hose requires less physical effort to control, particularly in ocean currents. The diver tools are made of materials that resist sea water corrosion, allow sea water to act as lubricants and that require little field maintenance. Test and evaluation is conducted for operability, safety, reliability, maintainability, and availability.

Computer models and Geographic Information Systems (GISs) are valuable tools for assessing nonpoint source discharges. Because of the diffused nature and variable flow associated with storm water run-off, it is difficult to design an inexpensive sampling program to assess the impact of nonpoint source pollution. Computer modeling and GISs can help process limited data and make assessments of nonpoint source discharges from both surface water and groundwater sources. Modeling approaches range from simple loading function calculations to the use of sophisticated hydrological and water quality-oriented computer software. GISs have great potential for reducing the cost of assessing nonpoint source pollution.

Results of laboratory model tests, inservice pier tests, classical plate theory, and finite element analyses provide the basis for changes in Military Handbook 1025/1 addressing flat slab pier dock design to distribute truck crane outrigger loads. The concentrated load distribution efficiency of Navy pier slabs can be doubled over current AASHTO allowables. For pier deck designs where large, truck-mounted cranes dominate load requirements, this will result in higher load capacity, longer spans, and less construction material. Further, the verified effectiveness of lateral load distribution would almost double outrigger load-carrying efficiency of current Navy pier decks.

In order to improve the productivity, safety and reliability of Marine Corps Material Handling Equipment (MHE) in a combat environment, this investigation was divided between two specific aspects of MHE operations. The predominant of these is High Speed Control (HSC). This concept involves the coupling of high flow hydraulics with an appropriately synthesized feedback control network in order to achieve system dynamic response two to three times faster than that achieved with conventional control systems, along with rapid convergence (seemingly critical damping following command signal crossover). The second aspect of MHE operations investigated is the enhancement of palletized cargo acquisition from ISO containers using the Marine Corps Extendable Boom Fork-lift (EBFL). Enhancement is by way of providing the EBFL operator with a stereoscopic three-dimensional video image, inside the cab, of the cargo- acquisition area, showing both the cargo pallet slots and the fork lift tines. Subsequently computer control can be integrated with the video image processing so as to facilitate or automate acquisition.

The objective of this project undertaken by the Naval Civil Engineering Laboratory (NCEL) is to develop a recycling technology for reducing the volume of boiler hydroblasting wastewater at Naval Shipyards by up to 90 percent. Steam boiler tubes of a Navy ship undergoing regular overhaul are cleaned twice by hydroblasting. The first washing is performed before ship overhaul and the second washing after ship overhaul. The initial feasibility study, completed in FY88, involved bench scale work at NCEL and pilot scale tests at Long Beach (LBNSY) and Norfolk Naval Shipyards (NNSY). Full scale field tests were conducted at NNSY in FY89. The wastewater recycling process consisted of five steps: collecting, settling, filtering, reconditioning, and reusing. All five steps were successfully demonstrated in the three series of field tests. These tests were assisted by and coordinated with NNSY and Naval Ship Systems Engineering Station (NAVSSES). The results show that the hydroblasting wastewater could be recycled nine times to achieve 90 percent reduction without any adverse effect.

This paper describes the conceptual design, predicted performance, and development plan for a new lost-cost design concept being developed for safety windows in both new and existing buildings. The concept protects the building interior against effects from accidental explosions outside the building, including blast overpressures, fragments, and debris. The shield transfers the applied window loads to the wall-ceiling and wall-floor joints where the building is inherently strong. This vastly reduces collateral building damage and the probability of structural collapse from an explosion. The design concept is a polycarbonate shield mounted in a steel frame suspended immediately behind the window opening from steel cables connected to the ceiling and floor. Energy absorbers and lead mass concealed inside the frame control dynamic response of the shield to an explosion. The cables restrain the shield to protect the building interior during the critical time when blast overpressures, casing fragments, glass shards, and debris act on the window.

This report presents a generalized numerical procedure for evaluating the responses of a modular construction floating platform subjected to static loads. The theory employed is applicable to watertight pontoon platforms undergoing unlimited rotations. This procedure enables users to investigate platform stability under various deck load configurations. Users are able to design a pontoon platform with prefabricated modules, check the platform for static stability, and modify the platform in a sequence resembling the actual design process. This procedure has been automated in a FORTRAN program to relieve users of the tedious iterations for the exact submerged hull geometry. Theories employed, analysis scenario, and program organization are discussed. The functions of the subroutines are also described in detail. The results predicted by the numerical procedure are in general agreement with measurements obtained from a full scale at-sea test of a modular construction platform. The conventional closed from solution based on initial water plane geometry can seriously underestimate the rotational excursion of a platform, if the deck loads are a significant part of the total displacement, or their centers of gravity are high. The present theory, which accounts for the instantaneous water plane, will be used for evaluating the static stability of such structures.

The purpose of this study was to investigate methods of repairing stilling basins of hydraulic structures underwater, thereby eliminating costly dewatering operations, and to develop a plan to evaluate products or concepts. The effort focused on methods using precast concrete or prefabricated steel panels. This report reviews underwater repairs of the Old River Low Sill Control Structure, Upper St. Anthony Falls Lock, and Kinzua Dam. An overview of the required underwater construction tasks is presented (preplanning, mobilization, surface preparation, installation of field anchors and panel supports, installation of panels, concrete placement, and inspection). Construction methods for underwater repairs are discussed, including the use of divers, wall enclosures, caissons, cofferdams, above-water platforms, and submersibles. Panel design factors considered are abrasion resistance, uplift forces, joints, and weight. Other panels considerations include shapes, joints, bond, and supports. It is feasible to relay on divers in underwater repair projects, because most stilling basins have low-water depths of 40 ft or less. Steel panels or composite steel-concrete panels are preferred to concrete panels because of the abrasion resistance of steel. Design details become important to assure that the steel panels remain serviceable under vibration and uplift forces from high- velocity water flow and impact from rocks in turbulent flow., Prepared in collaboration with Haynes and Associates, Oakland, CA.

This manual describes the operation and instructions for execution of the Conditional Ocean Wave Simulation Model (SIMBAT). SIMBAT is a high performance FORTRAN F77 based computer model that uses the Fast Fourier Transform (FFT) to produce ocean wave properties for ocean engineering applications. The model assumes the wave properties form a gaussian stochastic process. SIMBAT may be used to perform a conditional or unconditional simulation. A conditional simulation uses a measured or existing input time series and forces the simulated wave properties to adhere to the input time series but also follows the laws of multivariate normal probability. An unconditional simulation uses a measured or created ocean wave spectra to randomly simulate the ocean wave properties. Program features include: creation of directional ocean wave spectra; water particle kinematic stretching; conditioning time series using an input time series less than or equal to the simulation length; use of Legendre orthogonal polynomials for post creation of wave properties by program CKPOLY; and error checking. Examples problems are included.

Under the Underwater Construction System program, a seawater hydraulic tool system called the Multi-Function Tool System (MFTS) was developed. An objective of the MFTS development was to provide Underwater Construction Team divers with tools that meet their operational needs and were optimized for both the diver and the environment. A seawater hydraulic rock drill has not been issued because its performance is not predictable and its operation is not reliable. Extensive testing has isolated the problem to the impact mechanism and the timing of the cycle. Leakage of the supply poppet and the drive plunger as well as pressure pulsations from the rapid closing of the supply poppet have an undetermined negative affect on cycle operation. Cycle performance is not repeatable from test to test suggesting a transient or threshold condition that the drill is not always able to overcome. Additional development of the water lubricated impact mechanism is needed to investigate and correct these problems. While sea water is an attractive alternative to oil, it promotes sea water corrosion in metals, and the low viscosity of seawater offers minimal lubrication and high leakage rates compared to oils. These factors complicate the design of limiting material selection to those satisfying corrosion and lubrication criteria. In addition, close tolerance machining is necessary.

Base isolation (isolation of the columns of building using spring-damper systems) was found to offer significant potential for reduction of damage to essential Navy structures. This report review the principles of base isolation and presents site selection criteria. A design procedure for use of isolators on Navy mission essential construction was formulated. A detailed analysis of an isolated structure shows the significance of the isolator's nonlinear hysteretic behavior. Linear analysis techniques may underestimate structure displacements by 50 percent, and moments by 15 percent. Vertical acceleration effects which are usually neglected increase moments by about 15 percent. Simplified linear models of isolation, such as required by a response spectra analysis neglect the hysterisis of the isolator. A nonlinear analysis must be used to predict structure displacements. A single-degree-of-freedom (SDOF) representation of the structure on isolators was found to be highly accurate in predicting displacements, and yet simple enough to include in the design criteria. Use of only linear response techniques is not adequate.