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This is a guidance document of how to request an exemption from Standard Compliance (SC) under the US DOE's Energy Policy Act (EPAct).
This is an example of how to file for alternative compliance waiver application under the US DOE's Energy Policy Act (EPAct).
Structurally orthotropic shells analyzed by compliance method
Structural compliance induced cross axis coupling effect on gimballing system stability of rocket engine two-axis attitude TVC system
Structural compliance induced cross axis coupling effect on gimballing system stability of rocket engine two-axis attitude TVC system
Compliance analysis of structurally orthotropic shells
Extensometer for determining mechanical compliance of crack toughness test specimens
Hyperoxia and pulmonary surfactant washout in pulmonary compliance measurements of rats subjected to 100 percent diatomic oxygen before asphyxic death
Air and saline P-V curves of rat lungs after hyperoxia, comparing hyperoxia effects to surfactant washout on pulmonary compliance
Hyperoxia compared to surfactant washout on pulmonary compliance in rats
Single edge notch tension Al alloy specimens mechanical compliance measurement, solving stress functions for various gage length-sample width combinations
The adequacy is considered of currently practiced monitoring and data reduction techniques for assessing compliance with 24-hour Air Quality Standards (AQS) not to be exceeded more than once per year. The present situation for suspended particulates is discussed. The following conclusions are reached: (1) For typical less than daily sampling (i.e., 60 to 120 24-hour samples per year) the deviation from independence of the data set should not be substantial. (2) The interchange of exponentiation and expectation operations in the EPA data reduction model, underestimates the second highest level by about 4 to 8 percent for typical sigma values. (3) Estimates of the second highest pollution level have associated with them a large statistical variability arising from the finite size of the sample. The 0.95 confidence interval ranges from + or - 40 percent for 120 samples per year to + or - 84 percent for 30 samples per year. (4) The design value suggested by EPA for abatement and/or control planning purposes typically gives a margin of safety of 60 to 120 percent.
Compared are closure data produced on the same specimen by the crack tip compliance gage and electric potential techniques. Experiments on 7075-T651 aluminum center cracked panels produced equivalent results on closure using the two techniques. The results also indicated that closure is a function of stress ratio, specimen thickness and maximum applied stress intensity. Maximum stress intensity had a strong effect on closure in the range of applied stresses used. This dependence of closure on specimen thickness and maximum stress intensity accounts for many of the discrepencies in closure behavior reported in the literature.
The objective of this study was to compare closure data obtained on the same specimen with crack tip compliance gage and electric potential techniques. Equivalent results on closure using the two techniques were obtained on 7075-T651 aluminum center cracked panels. The results also indicated that closure was a function of stress ratio, specimen thickness and maximum applied stress intensity. Maximum stress intensity had a particularly strong effect on closure in the range of applied stresses used. This observed dependence of closure on specimen thickness and maximum stress intensity should account for many of the discrepancies in closure behavior found in the literature. Observations on potential system behavior during closure measurements are also reported.
Standard round specimen fracture test results compared satisfactorily with results from standard rectangular compact specimens machined from the same material. The location of the loading pin holes was found to provide adequate strength in the load bearing region for plane strain fracture toughness testing. Excellent agreement was found between the stress intensity coefficient values obtained from compliance measurements and the analytic solution proposed for inclusion in the standard test method. Load displacement measurements were made using long armed displacement gages and hollow loading cylinders. Gage points registered on the loading hole surfaces through small holes in the walls of the loading cylinders.
For the determination of fracture toughness especially with brittle materials, a short bar specimen with rectangular cross section and chevron notch can be used. As the crack propagates from the tip of the triangular notch, the load increases to a maximum then decreases. To obtain the relation between the fracture toughness and maximum load, calculations of Srawley and Gross for specimens with a straight-through crack were applied to the specimens with chevron notches. For the specimens with a straight-through crack, an analytical expression was obtained. This expression was used for the calculation of the fracture toughness versus maximum load relation under the assumption that the change of the compliance with crack length for the specimen with a chevron notch is the same as for a specimen with a straight-through crack.
Compliances and stress intensity coefficients were determined over crack length to width ratios from 0.1 to 0.8. Displacements were measured at the load points, load line, and crack mouth. Special fixturing was devised to permit accurate measurement of load point displacement. The results are in agreement with the currently used results of boundary collocation analyses. The errors which occur in stress intensity coefficients or specimen energy input determinations made from load line displacement measurements rather than from load point measurements are emphasized.
The short rod chevron-notch specimen has the advantages of (1) crack development at the chevron tip during the early stage of test loading, and (2) convenient calculation of plane-strain fracture toughness from the maximum test load and from a calibration factor which depends only on the specimen geometry and manner of loading. For generalized application, calibration of the specimen over a range of specimen proportions and chevron-notch configurations is necessary. Such was the objective of this investigation, wherein calibration of the short rod specimen was made by means of experimental compliance measurements converted into dimensionless stress intensity factor coefficients.