bluuebunny/crossref_metadata_2025_split huggingface dataset:
Establishing Uplift Design Values for Metal Connectors in Light-Frame Construction
Authors: Rosowsky DV , Reed TD , Tyner KG 
Published: May 2009

Abstract
Wind loads cause uplift pressures to be applied to a roof resulting in a net uplift force on the structure. One of the most critical locations in the vertical load path is the connection between the roof and the wall, specifically between the roof rafter (or truss) and the top-plate of the wall. This connection is typically made using mechanical fasteners such as metal straps and nails. The manufacturers of these straps provide allowable capacities for their products based on ASTM test procedures for tension straps, joist hangers, or other similar products. Manufacturers' published design capacities for hurricane straps are based on the lowest value of three test criteria. The first criterion is the ultimate uplift load divided by three, the second is the load 1/8 in. (3.2 mm) deflection, and the third is the allowable design values for nails or other fasteners used to attach the connector to wood members. Recent test results suggest these values may be overly conservative in some cases and that some test criteria or procedures may not be representative of actual design conditions. This paper first reports on a testing program to evaluate uplift capacities of lightframe connections made using commonly available hardware. Based on an evaluation of the results and observations made during the tests, shortcomings of current test procedures and testing program details are described. Deficiencies, and specific needs to overcome them, are identified in the context of structural performance as well as safety.
Measuring the Triaxial Load-Deformation Response of Orthotropic Materials Subjected to Large and Small Strain Regimes
Authors: Saliklis EP , Cramer SM , Hermanson JC 
Published: May 2009

Abstract
A new method for obtaining triaxial stress versus strain data is presented. The method tests cubic specimens and can provide constitutive data along three mutually perpendicular axes. Issues of removing the effects of boundary conditions in the proposed device are discussed. Two devices were constructed and used to obtain triaxial stress versus strain data on paperboard and on redwood samples. Representative data are shown.
Durability of Geosynthetics Based on Accelerated Thermo-Oxidation Testing
Authors: Salman A , Goulias D , Elias V 
Published: May 2009

Abstract
With the increasing use of geosynthetics in civil engineering applications, the geosynthetic industry has developed new and more sophisticated materials. As improved geosynthetics are being introduced, it is necessary to assess their durability with respect to the environmental conditions that they will be exposed to. This requires the development of accelerated tests permitting the degradation prediction of geosynthetics in actual use. To address this need, a basic autooxidation scheme (BAS) has been adapted so as to develop a kinetic model for evaluating their mechanical degradation. Based on the experimental data, the model provides estimates of strength loss with time caused by thermo-oxidation.
A Potential Optical Standard for Resistance Strain Gages
Authors: Sharpe WN 
Published: May 2009

Abstract
The laser-based interferometric strain/displacement gage (ISDG) is an optical technique that measures the change in relative distance between two reflective markers on a specimen surface. When the markers are illuminated with a low-power He-Ne laser, interference patterns are formed in space that can be monitored and related to the relative displacement between them. The ISDG has been used in experiments ranging in duration from 10 μs to 1000 h—a dynamic range of eleven orders of magnitude. This noncontacting technique offers some intriguing possibilities for resistance strain gage calibration. It does not have to be compensated for temperature since there is no thermal expansion of the gage. There are no transverse effects since it measures only the strain along the line between the two markers. It can measure biaxial strains if three markers are placed in an orthogonal pattern. With high-speed detectors, the ISDG can have a very high-frequency response. The fringe motions can be tracked by following the maximums or minimums of the patterns so there is no drift in the electronic instrumentation, which makes the ISDG suitable for calibration of gages used to measure creep strain.
This paper presents a brief overview of the ISDG and discusses application areas where it may be useful in evaluating the performance of resistance strain gages. The two applications where it is most likely to be useful are when elastoplastic strains are measured in regions of high gradients or when the strain is dynamic and elastoplastic.
Additional Comments About a Modified Theodolite Instrument: Conceptual Work
Authors: Obaidat MT , Al-Smadi ZA 
Published: May 2009

Abstract
We previously described a modified surveying theodolite in which the head can be set in a second more elevated position by means of a sliding calibrated extension rod, thus allowing through triangulation the measurement of otherwise inaccessible distances or heights of objects. The recommended sequence of operations required the tilting of the extended rod of the instrument away from the plumb line in order to determine such a distance or height. Unfortunately, this tilting adversely affects the mechanical stability of the instrument. However, it is possible to make triangulation measurements without tilting the rod away from the normal. A new sequence of operations is presented in which the height of a distant object, horizontal distances, and slope distances can be calculated as functions of two measured angles of elevation and the length of the extended rod (along the normal, or plumb line) only. This operational modification has the advantages over the earlier-described procedure of simplicity, lower cost, convenience, greater mechanical stability, and increased precision of measurement.
Measurement and Interpretation of Fatigue Crack Growth in 7075 Aluminum Alloy Using Acoustic Emission Monitoring
Authors: Gong Z , DuQuesnay DL , McBride SL 
Published: May 2009

Abstract
A method for monitoring crack growth during highcycle fatigue tests was demonstrated using acoustic emission (AE) monitoring. Windowing techniques were employed during the recording and interpreting of the AE data. The results provided linear relationships between AE events and amplitudes and crack lengths. The fatigue crack growth results from the AE data were in very good agreement with data measured using an optical microscope.
Fractographic observations of the crack and specimen surfaces showed that secondary cracks formed and linked to the main crack during intermediate stages of crack growth. The crack growth rate calculated from AE data reflected the formation of secondary cracks in this period.
Creep Test of Cured-In-Place Pipe Material Under Tension, Compression, and Bending
Authors: Straughan WT , Tantirungrojchai N , Guice LK , Lin H 
Published: May 2009

Abstract
Inexpensive and easily fabricated long-term creep test devices have been designed and built in order to identify the long-term creep behavior of cured-in-place pipe (CIPP) material under tension, compression, and bending. A special device for testing curved specimens has been designed, built, and evaluated. Loads were applied for 3000 h, and the deformations of CIPP specimens were recorded. Findley's equation, which has been successfully used to predict the creep behavior of plastics for more than 25 years, was used as a baseline for data analysis. The results from Findley's approach were compared with the results from the analyses by theoretical and log-fit methods. The comparison of the three approaches shows that the best estimation of 3000-h creep moduli can be obtained by using the log-fit method.
Effect of Loading Parameters on Post-Overload Fatigue Crack Closure
Authors: Verma BB , Pandey RK , Chinnadurai R 
Published: May 2009

Abstract
The tensile overload cycle has a significant effect on fatigue behavior, resulting in an enhanced crack closure level and reduced fatigue crack growth rate. The present investigation studies the effect of opening mode tensile overload on crack closure in 2024-T3 aluminum alloy and 4130 Cr-Mo steel sheets. It is found that the overload-induced closure parameter KopOLincreases with basic stress intensity range ΔK and overload level. The result further indicates that the significant closure effect can be obtained only beyond a limiting level of overloading ratio (OLR)=1.30 in both the alloys, where OLR is the ratio of the maximum stress-intensity factor in the overloading cycle to the maximum stress-intensity factor in the constant-amplitude loading cycle.
Dynamic Fracture Toughness Measurements on Small Charpy Specimens—A Preliminary Study
Authors: Sharpe WN , Böhme W 
Published: May 2009

Abstract
A technique for measuring dynamic fracture toughness on small specimens is described and preliminary data are presented. Dynamic crack tip opening displacements (CTODs) are measured with laser interferometry over times as short as 10 μs. The measured displacement is converted to stress intensity values via the equations of linear elastic fracture mechanics and the peak value obtained is taken as the dynamic fracture toughness.
Two materials were tested at two different loading rates; a brittle plastic at 103 and 104 MPa-m1/2/s and a ceramic 5 × 104 and 106 MPa-m1/2/s. The results from this new technique were compared with simultaneous results from an instrumented Charpy hammer and, in some cases, from foil gages on the specimens. At the slower rates, the agreement among the results is acceptable. At the higher rates, the instrumented hammer technique is no longer valid. The technique is potentially useful on small, brittle specimens at room and high temperatures.
Controlling, Data Acquisition, and Data Processing for Axial and Shear Creep Tests Using a Computer
Authors: Schmitt FC , Matthews JM 
Published: May 2009

Abstract
The objective of this paper is to provide an inexpensive way of conducting uniaxial creep and shear creep tests, data acquisition, and data processing using a computer. A microcomputer, a math coprocessor, and a graphics laser jet printer were used. A multi-function analog-digital-input-output expansion board increased the computer capacity enabling better precision, data acquisition, and signal analysis. A load cell was used to measure the loads while two linear variable differential transducers (LVDT) were used to monitor the deformations. A signal conditioning unit was used to excite the load cell and LVDTs and to transform the voltage output of the two digital analog channels into electric currents.
Software developed at the University of California, Berkeley was used to conduct the tests. Hard copies of the computer output were obtained showing the relationship between the creep compliance and the time of loading. An example of the application of the creep test results for predicting the permanent deformation of the asphaltic layer of a heavy duty highway is included.
Practical Aspects of Dynamic Verification of Extensometers: Part II—Actual Examples
Authors: Albright FJ , Annala J 
Published: May 2009

Abstract
Verification and calibration of an extensometer requires operation at multiple points within the desired operating range. Whereas static calibrations observe changes in sensitivity at different levels within the transducer operating range, dynamic calibrations require duplicating that range of test levels for a range of operating frequencies. Additionally, although the static accuracy of an extensometer is relatively independent of the test machine, dynamic accuracy was believed to be quite dependent.
Test results for dynamic verification of several extensometers are presented. The focus of the tests was to gain an understanding of the advantages and disadvantages of different methods of verification. Testing was generally in accordance with ASTM E 467, Practice for Verification of Constant Amplitude Dynamic Loads in An Axial Load Fatigue Testing Machine. Two excitation methods were used: discrete frequency and pseudo-random. Evaluation of a proposed revision to ASTM E 467 is included. Use of a computer to provide an efficient, high-accuracy method of verifying the calibration of an extensometer was explored. Further testing is recommended to determine if extensometer dynamic verification must be done on the actual test setup, and to what extent it is repeatable.
Measurement Uncertainty Analysis of a Transfer Standard Force Calibration System
Authors: Tovey FM 
Published: May 2009

Abstract
Force transducer calibration may be performed by means of dead weights or by comparison with a transfer standard. Directly applied dead weights with traceability to the National Institute of Standards and Technology (NIST) are primary force standards. Low-capacity force transducers are generally calibrated by primary standards, but for force transducer calibrations above 1000 lb (453.6 kg), many force transducers are calibrated by means of secondary force standards used as transfer standards. The purpose of this paper is to provide a measurement uncertainty analysis of transfer standard force calibration at one test facility. Significant error sources are identified and quantified. The methodology presented is generally applicable; however, the error evaluations are specific to the measurement process and test equipment used.
A New Restraint for High-Load-Transfer Fastener Fatigue Test
Authors: Yigang Z , Xueren W , Yongan Y 
Published: May 2009

Abstract
A test somewhat different from the MIL-STD-1312 test 21 (Shear Joint Fatigue-Constant Amplitude) was explored by using a new type of restraint. Rivet fasteners of two kinds of materials were tested under constant amplitude fatigue loading. The new restraint facilitated the test program and reduced the bending load more efficiently than the current method. Fatigue behavior of aluminum alloy and high-strength steel with single-lap rivet fastener specimens was investigated under different load levels.
Thermal and Mechanical Properties of Cellular Polystyrene and Polyurethane Insulation Materials Aged on a Flat Roof in Hot-Dry Climate
Authors: Ozkan E 
Published: May 2009

Abstract
Cellular polymers, which have been increasingly used for thermal insulation of external walls and roofs since the 1970s, degrade in some cases. The heat transmission of a cellular polymer insulator, the k value, is predominantly dependent on the heat conduction of the air or gas remaining in the cells. An insulator may be aged and start transmitting more energy due to replacement of cell content with different gases or moisture or both, changes in size, softening and creeping under pressure and heat, or penetration of water or mineral particles into cells, or a combination thereof. The solid face also degrades due to ultraviolet light, heat and atmospheric oxygen.
A research project was carried out from January 1988 to December 1991 to investigate the performance of flat roofs, waterproofing, and thermal insulation materials in the hot-dry climatic region of Saudi Arabia. In this context a field station was built and operated for weathering of roofing and insulation materials and for monitoring the surface and the inner temperatures of the applied roof systems.
Basically, two types of cellular polymers, expanded polystyrene and foamed polyurethane, were installed on the roof of the station for insulation. Specimens taken from the fresh, stored, and weathered polystyrene and polyurethane foams were tested to evaluate them according to the selected properties of thermal conductivity, compressive strength at relative deformation, and dimensional stability at elevated temperature. The test results were compared with the requirements presented in the literature and the standard specifications.
Data Analysis Techniques for Impact Tests of Composite Materials
Authors: Svenson AL , Hargrave MW , Bank LC , Ye BS 
Published: May 2009

Abstract
This paper discusses data analysis techniques for instrumented impact tests conducted on glass fiber composite materials. For this study, a drop weight tower has been instrumented with an accelerometer and computer data acquisition system. From the acceleration data obtained, load, energy, velocity, and displacement are calculated in a spreadsheet environment. The resulting data from multiple tests for each material type considered are then averaged producing average plots. The standard deviation is also calculated and plotted for the load data. These curves are then used to characterize the impact behavior of the material. Also introduced is a procedure by which results are normalized by all geometric parameters present in the impact test. This method provides for comparison of test data from three-point bend impact tests having differing geometric parameters.
A Differential Air Deflation Quality Assurance Test for Surgical Gloves
Authors: Carey RF 
Published: May 2009

Abstract
A new quality assurance (QA) test for surgeon's gloves is described which uses a sensitive differential pressure gage to detect glove holes as small as 0.020 mm. The test can be performed quickly and without damage to the glove. Standard holes in nickel masks, ranging in diameter from 0.015 mm to 0.10 mm, were used to calibrate test sensitivity. Air pressure losses in test gloves were compared directly to air pressure in an intact glove. Holes in glove fingers and in glove palms were made with an excimer laser and also with an acupuncture needle. These gloves were then tested with this differential air deflation test and with the standard 1000 mL water fill test. The new test offers similar test sensitivity to the 1000 mL test and, in addition, offers the possibility of quantitative leak testing.
Effects of Sample and Test Variables on Electrical Wire Insulation Flammability
Authors: Rodak EM , Taylor RJ , Hirsch DB , Linley LJ 
Published: May 2009

Abstract
A new test method has been adopted to evaluate the flammability of electrical wire insulation materials. In this test, wire insulation is exposed to an external ignition source while the electrical conductor is internally heated by an electric current. The repeatability of the test and the effects of wire gage and insulation thickness, internal wire temperature, and sample orientation on the wire insulation flammability were evaluated. Experimental results showed that the new test is a practical and repeatable method for evaluating flammability of wire insulation materials.
Effect of Overload Cycles on Thin Steel Roof Claddings during Cyclonic Winds
Authors: Mahendran M 
Published: May 2009

Abstract
During an investigation on thin steel roof claddings under simulated cyclonic wind loading, it was found that trapezoidal roof claddings behaved quite differently to corrugated (arc and tangent type) roof claddings due to the presence of overload cycles. The overload cycles caused a reduction in fatigue life for corrugated roofing whereas the reverse occurred for trapezoidal roofing. This contrasting behavior of the two crest-fixed roof claddings was investigated using small scale roofing models instead of the commonly used large scale two-span roof claddings. It was found that overload cycles formed a weaker locally dimpled mechanism around the fastener holes of corrugated roofing and thus accelerated the fatigue-caused pull-through failure. In contrast, a stronger deformed shape was formed in trapezoidal roofing which delayed the pull-through failure. Both laboratory testing and finite element analysis of small scale models were used to study the contrasting behavior of roof claddings.
Effect of Composition of El-lajjun Oil Shale on Its Calorific Value
Authors: Anabtawi MZ , Nazzal JM 
Published: May 2009

Abstract
A geochemical analysis of El-lajjun oil shale in Jordan was carried out. It was found that El-lajjun oil shale consists of the following groups: organic matter, biogenic calcite and apatite, detrital clay minerals, and quartz. The calorific values of 100 samples of shale were determined. The effect of bore depth, calcium carbonate, organic carbon, and sulfur content on the calorific values were studied. Results were well correlated by the following equation Calorificvalue=352,44(CaCO3)-0.066(S)0.257(Corg)1.141 with correlation coefficient of 0.983 and with an average standard error of 2.63%.
Intramyocellular triglyceride content in man, influence of sex, obesity and glycaemic control
Authors: Haugaard Steen B , Mu Huiling , Vaag Allan , Madsbad Sten 
Published: May 2009

ObjectiveIt remains unknown whether sex impacts on intramyocellular triglyceride (IMTG) in obesity, as has been shown in non-obese subjects, and, if so, whether this may have implications on the association between IMTG and insulin sensitivity.Subject and methodsA muscle biopsy from vastus lateralis was obtained in 27 obese women (body mass index (BMI)=35.5±0.8 kg/m2; mean±s.e.m., percentage of body fat (PBF)=44±1, n=7  impaired fasting glucose, n=7 type 2 diabetes), 20 obese men (BMI=35.8±0.8 kg/m2; PBF=33±1, n=4 impaired-fasting-glucose; n=6 type 2 diabetes) and 12 lean sedentary healthy individuals (controls; n=7 women, BMI=21.8±0.7 kg/m2, PBF=20±2; n=5 men, BMI=23.6±0.5 kg/m2, PBF=13±2). IMTG was determined by chromatography.ResultsIMTG was increased twofold in obese women compared to obese men, lean men and lean women respectively (21.9±2.4 mg/g wet weight, 10.9±1.5, 9.8±2.1 and 10.9±2.4 mg/g, P<0.001). Among obese subjects of either gender IMTG did not increase along with reduced glycaemic control in terms of impaired fasting glucose and diabetes. Plasma insulin levels, which were similar among obese women with different glycaemic control levels, but much lower in lean women, paralleled the changes in IMTG among women. PBF was associated with IMTG in all subjects (P<0.001). In a linear model, sex (P<0.05) and PBF (P<0.05) independently explained variation in IMTG. Plasma free fatty acids (FFA) correlated with IMTG in all subjects (P<0.005).ConclusionObese women display twice as much IMTG as obese men matched for BMI. Increased IMTG could be a pathophysiological element or a mere physiological phenomenon in feminine obesity ensuing prior to impaired glycaemic control, but associated with increased body fat, circulating FFA and insulin.
The StrongWomen–Healthy Hearts Program: Reducing Cardiovascular Disease Risk Factors in Rural Sedentary, Overweight, and Obese Midlife and Older Women
Authors: Folta Sara C. , Lichtenstein Alice H. , Seguin Rebecca A. , Goldberg Jeanne P. , Kuder Julia F. , Nelson Miriam E. 
Published: May 2009

Objectives. We tested a community-based intervention designed to reduce cardiovascular disease risk in sedentary midlife and older women who were overweight or obese. Methods. In a randomized controlled trial conducted in 8 counties in Arkansas and Kansas, counties were assigned to the intervention (a 12-week twice-weekly heart health program) group or to the delayed-intervention control group. Ten to fifteen women were selected from each site, and participants' weight, waist circumference, diet, physical activity, and self-efficacy were measured before and after the intervention. Data were analyzed with multiple regressions. Results. Compared with the control group, participants in the intervention group had a significant decrease in body weight (−2.1 kg; 95% confidence interval [CI] = −3.2, −1.0), waist circumference (–2.3 in; 95% CI = −4.2, −0.5), and energy intake (–390 kcal/day; 95% CI = −598, −183); an increase in activity (+1637 steps/day; 95% CI = 712, 2562); and an increase in self-efficacy for dietary and physical activity behaviors. Conclusions. Our results suggest that a community-based program can improve self-efficacy, increase physical activity, and decrease energy intake, resulting in decreased waist circumference and body weight among at-risk women.