Existing Test Procedures Research Articles

Bromhead Ring Shear Test Procedure

Abstract Existing test procedures and a proposed modification for the Bromhead ring shear apparatus were found to yield drained residual strengths higher than values back-calculated from field case histories. A new test procedure is presented that yields drained residual strengths that are in excellent agreement with field case histories. The new test procedure utilizes the unmodified Bromhead ring shear apparatus and limits the settlement of the top porous stone, due to consolidation and/or soil extrusion during drained shear, to 0.75 mm. Since the specimen is confined radially by the specimen container, limiting the settlement of the top porous stone minimizes the wall friction that develops along the inner and outer circumferences of the specimen. The reduced wall friction results in the lowest measured residual strength and the best agreement with field case histories.

Cost accounting for blood bank laboratories

Abstract To meet the challenges of present-day blood banking, laboratory managers and supervisors must acquire and use skills in financial management. One such skill is cost analysis. Cost analyses vary from simple to complex and are used to determine the basic elements contributing to a test cost. Cost analysis can be used to identify costs, justify updating laboratory test prices, monitor general supply and reagent costs, help in the decision to lease or buy an instrument, modify existing test procedures to cut costs, determine staffing needs, and assure accurate reimbursement for laboratory services.

The Dimethyl Sulfoxide (DMSO) Accelerated Weathering Test for Aggregates

Abstract A standard accelerated weathering test using dimethyl sulfoxide (DMSO) was developed to simulate the chemical degradation of basaltic rock. The final development of the standard test involved a study of the interaction of DMSO with clay standards and an investigation of the test condition parameters affecting an existing DMSO test procedure. The weighted loss reported under the existing test procedure (similar to the sodium sulfate soundness test) was affected by the aggregate particle size, specimen mass, immersion time, and container geometry. In the recommended standard DMSO accelerated weathering test, aggregates in the particle size range of 2.4 to 4.8 mm are immersed in a container of DMSO for a period of five days. The mass loss determined by re-sieving the material on a 2.4-mm (No. 8) sieve after five days immersion provides a measure of durability. Immersion of basaltic aggregates in DMSO results in a greater breakdown owing to the type and concentration of ions contained in the rock matrix. Specifically, it was found that DMSO reacts with the cations held to the swelling clay minerals in the aggregate. The results from Atterberg limits tests indicate that DMSO substantially reduces the liquid limit for clays with high activities and increases the liquid limit for clays with low activities. The changes in the liquid limits were influenced by the interaction of DMSO with cations held on the surface of the clay mineral and the ability of DMSO to donate hydrogen ions.

Theory of one-dimensional consolidation of saturated clays: III. Existing testing procedures and analyses : Znidarcic, D; Croce, P; Pane, V; Ko, H Y; Olsen, H W; Schiffman, R L Geotech Test JV7, N3, Sept 1984, P123–134

Theory of one-dimensional consolidation of saturated clays: III. Existing testing procedures and analyses : Znidarcic, D; Croce, P; Pane, V; Ko, H Y; Olsen, H W; Schiffman, R L Geotech Test JV7, N3, Sept 1984, P123–134

Closure to “Discussion of ‘The Theory of One-Dimensional Consolidation of Saturated Clays: III. Existing Testing Procedures and Analyses’ by A. K. Parkin” by D. Znidarcic, P. Croce, V. Pane, H.-Y. Ko, H. W. Olsen, and R. L. Schiffman

Closure to “Discussion of ‘The Theory of One-Dimensional Consolidation of Saturated Clays: III. Existing Testing Procedures and Analyses’ by A. K. Parkin” by D. Znidarcic, P. Croce, V. Pane, H.-Y. Ko, H. W. Olsen, and R. L. Schiffman

Discussion of “The Theory of One-Dimensional Consolidation of Saturated Clays: III. Existing Testing Procedures and Analyses” by D. Znidarcic, P. Croce, V. Pane, H.-Y. Ko, H. W. Olsen, and R. L. Schiffman

Discussion of “The Theory of One-Dimensional Consolidation of Saturated Clays: III. Existing Testing Procedures and Analyses” by D. Znidarcic, P. Croce, V. Pane, H.-Y. Ko, H. W. Olsen, and R. L. Schiffman

The Theory of One-Dimensional Consolidation of Saturated Clays: III. Existing Testing Procedures and Analyses

Abstract The successful calculation of the progress of consolidation requires that both the theory used to model the field problem and the material properties used by the theory must be appropriate and suitable. Thus the testing procedure must provide reliable and consistent information on the material behavior. Further, the test procedure must be accompanied by methods of analysis that will produce values of the material properties that are appropriate to the theory. This paper presents a summary of the existing laboratory methods that are used to determine the consolidation properties of soils. Emphasis is placed on the analysis of the test data. It is shown that all the methods that are currently used contain inherent simplifying assumptions. These methods are restricted in their applicability to problems where linear or constant material properties or both are good approximations to real behavior.

Grouping Tests for Misspecification: An Application to Housing Demand

We consider several grouping tests for regression misspecification, with reference to housing-demand function estimation. We compare three existing test procedures, demonstrate modifications necessary in most applications, and propose a fourth test to distinguish between two categories of potential specification error. The test procedures are evaluated in artificial simulations of alternative errors. Finally, we apply the tests to FHA home purchase data. We reject the hypothesis that household and grouped regressions differ only by sampling error or random mismeasurement of household income or price. Our results have implications for choices among test procedures and interpretations of previous housing-demand analysis.

Evaluating Rhizobium viability in commercial inoculum

Commercial inoculum prepared with a peat base is subject to many factors that can reduce viability prior to and after retail purchase. No standards of quality are available to protect the consumer. Quality control of inoculum viability would be helpful but existing test procedures are time consuming and details have not been clearly defined for routine use. The objective of this paper is to describe a method for testing commercial inoculum quality by determining the number of viable rhizobial cells per gram of peat-base carrier. These procedures can be used by extension personnel to assure high quality inoculum sources. Also, students in college and high school crop production courses can use the procedures as a learning aid through laboratory exercises. These procedures can be used to test viability of nodulating bacteria on seed sold with preinoculated coatings. Evaluation procedures are based on a plant infection test. Seedlings of the species compatible to the inoculum are produced from sterilized seed in plastic growth pouches. Rhizobial cells in the peat-base carrier are suspended in water. Ten-fold serial dilutions are made until there is theoretically one Rhizobium cell per 100 ml. Five pouches of each of the five greatest dilutions are inoculated. Presence of nodules is scored after several weeks of growth. Numbers of rhizobial cells in the commercial inoculum are obtained from a Most-Probable-Number table. A minimum of 107 bacteria per gram of inoculum is suggested as a standard of good quality. Several packages of commercial inoculum we tested failed to meet this standard.

Tests for multivariate normality with pearson alternatives

We consider a multivariate Pearson family of distributions. Certain parametric restrictions lead to the multivariate normal distribution. Using this fact we propose a number of asymptotically efficient tests. Through Monte Carlo experiments these tests are compared with some of the existing test procedures. A table is provided from which finite-sample critical points can be obtained.

Incident Angle Modifiers for Flat-Plate Solar Collectors: Analysis of Measurement and Calculation Procedures

Existing test procedures for measuring and rating thermal performance require the determination of the angular response of collectors in order to account for non-normal incident beam irradiance. Angular response measurements for four different types of collectors, each type tested by three different laboratories, are presented and analyzed. Substantial differences, both within and between laboratories, are reported for the same type collectors. An analysis of the measurement procedure shows that experimentally determined angular response parameters are subject to relatively large uncertainties. The problem results to a large extent from measuring collector efficiencies at non-normal incident angles where measurement uncertainty is of the same order of magnitude as the efficiency reduction attributable to these off-normal angles. Other factors which can affect angular response measurements and the method of correlating results are also discussed. A theoretical analysis shows that shading of the absorber by the collector air space side- and end-walls for non-normal incident angles can be of the same order of importance as the decrease in the transmittance of the cover assembly. While this situation complicates an analytical approach, it is concluded that calculations are adequate to depict the angular response of conventional flat-plate tube-in-sheet collector designs. A simplified analytical procedure and nomographs are presented for rapid calculation of incident angle modifiers. The predicted seasonal performance of solar energy systems and clear-day ratings of typical flat-plate collectors are shown to be relatively insensitive to large uncertainties in incident angle modifiers. Typically, the values of these calculated quantities could be affected by approximately five percent as a result of uncertainty in the test-derived angular response parameter.

Early Assessment of Concrete Quality by Accelerating Compressive Strength Development with Heat (Results of ASTM's Cooperative Test Program)

Abstract Rapid concrete construction practices have led to increasing pressure to assess the quality of concrete at a very early age. Therefore, a cooperative test program was conducted among nine laboratories to evaluate several existing test procedures involving the use of either hot water, boiling water, or the heat of hydration of portland cement to provide heat necessary to accelerate the compressive strength development of concrete. Depending upon which procedure was employed, the amount of acceleration ranged from 1.1 to 2.5 times the strength developed after the same period of moist curing. Statistical analyses of the data justified adoption of a standard method that can be used to judge the quality of concrete soon after mixing. This method involves three procedures of accelerated curing which are limited to concrete made with the same materials and tested by the same laboratory. It has been designated ASTM C 684-74 (Making, Accelerated Curing, and Testing of Concrete Compression Test Specimens). Use of it, under the conditions stated therein, results in as reliable an evaluation of the quality of the concrete at one or two days of age as compared to that measured at 28 days of age according to ASTM C 31-69 (Making and Curing Concrete Test Specimens in the Field).

Concrete testing - wet and dry : Baxter, M 1F Civ Engng Nov. 1974, P43–45

The article introduces a new method of testing concrete and reviews some of the problems of existing testing procedures. The cement and concrete association (c&ca) have developed A machine costing found1250 which runs on 240 volts electric supply and reads out the cement content of an 8 kilogramme sample of concrete with a standard deviation of 21 grammes. If pulverised fuel or similar cement substitute is present the machine cannot distinguish between the two. A subsidiary test is then required to determine the proportions accurately. The operator has to put in 8 or 10 kilogrammes of fresh concrete and in about 5 minutes time a graph is obtained of the cement content, the machine cleans itself during the operation and there is no danger of dried concrete affecting the accuracies of the next test. The main advantage of this method is that the testing is done before the concrete is laid. /TRRL/

Development Of CNC Machine PerformanceStandards

This paper summarises our approach to a new EU project to investigate current and proposed ISO machine tool standards by conducting tests on a range of CNC machine tools to investigate and report on the feasibility of improvements to existing test procedures. A partnership of six EU companies has been established to review the limitations of current test procedures, and to investigate possible enhancements that may be required. This paper summarises some of the preliminary work which has led to the establishment of this new project. It is submitted as part of an ongoing discussion procedure to gather suggestions for enhancements that can be examined during the two years of the project. Some preliminary results are shown to assist these discussions. Current ISO machine tool standards position We have briefly listed the current standards that are used, and shown when they are due for revision. Revisions always take several years of consultation to be considered and issued as a proposed standard, then issued as Drafts for Public comment (DC). After comments are received from the engineering community at large they are then reconsidered and issued as Draft ISO standards (DIS), and again circulated for further comment After that stage a standard is issued as a Final Draft Standard (FDIS), for final acceptance after a final round of comments.[l] ISO 230-2 Accuracy & Repeatability Current standards are well defined for 'normal' sized machining centres (i.e. axis lengths up to 2 metres), but do not give acceptable procedures for large machines. It is now apparent that Transactions on Engineering Sciences vol 23, © 1999 WIT Press, www.witpress.com, ISSN 1743-3533

Proving the performance of circuit-breakers, with particular reference to those of large breaking capacity

For more than 20 years the technique of short-circuit testing has been advanced steadily. To-day it has reached a high state of development, and it is opportune to examine the position. In the paper the characteristics of the main types of circuit-breaker are briefly summarized, and the various aspects of test-circuit severity are considered, both in relation to actual service conditions and to their effects upon the different types of circuit-breaker. Existing test procedures and methods are reviewed, and suggestions are made for the improvement of some of them and for their being brought more into line with present service requirements. Proposals are also made for methods of approach to certain tests which it has not yet been possible to standardize. Particular attention is paid throughout to the problems associated with the testing of large circuit-breakers. Finally a brief reference is made to the part played by field tests and the requirements of a modem testing station.