33. Studies of elastic modulus of irradiated graphite by means of an ultrasonic pulse method

Carbon ◽  
1964 ◽  
Vol 1 (3) ◽  
pp. 362 ◽  
Author(s):  
Sennosuke Sato ◽  
S Miyazono
Keyword(s):  
Elastic Modulus ◽  
Pulse Method ◽  
Ultrasonic Pulse ◽  
Irradiated Graphite

In Situ Determination of the Elastic Modulus of Concrete by Means of Ultrasonic Pulse Method

2018 ◽  
Vol 272 ◽  
pp. 70-75
Author(s):  
Petr Cikrle ◽  
Dalibor Kocáb ◽  
Barbara Kucharczyková ◽  
Ondřej Anton
Keyword(s):  
Elastic Modulus ◽  
Pulse Method ◽  
Ultrasonic Pulse ◽  
In Situ Measurements ◽  
Test Method ◽  
Destructive Test ◽  
Non Destructive ◽  
Thick Layers

The paper deals with the in-situ determination of the modulus of elasticity on the bridge elements using ultrasonic pulse method. This non-destructive test method was chosen for the measurement because of its undisputed advantages that allow the measurement of relatively thick layers of material. For the purpose of the elastic modulus verification the direct measurement was used, in which a pair of transducers (transmitter and receiver) were placed directly opposite to each other. The results of performed in-situ measurements as well as the results of verification tests performed in the laboratory are presented in the paper. The article also discusses the issue of evaluation and interpretation of the results obtained by in-situ measurements using non-destructive test method.

scholarly journals Improvement of Accuracy of Control of Physical‑Mechanical Characteristics of Materials By Ultrasonic Pulse Method Due to Reduction of Measurement Error of Propagation Time of Elastic Waves

2018 ◽  
pp. 31-35
Author(s):  
Ya. Serikov
Keyword(s):  
Mechanical Characteristics ◽  
Pulse Method ◽  
Structural Heterogeneity ◽  
Ultrasonic Pulse ◽  
Ultrasonic Signal ◽  
Ultrasonic Transducers ◽  
Propagation Time ◽  
Information Signal ◽  
Pass Through ◽  
Definition Of

Ensuring the reliability of buildings, structures, analysis of their structural elements during reconstruction or major repair includes the task of determining the physical and mechanical characteristics of materials — strength, homogeneity, evaluation of structural heterogeneity, the presence of microcracks, etc. In solving this problem, an ultrasonic pulse method of non-destructive quality control is used. The basis of the method is the dependence of the parameters of ultrasonic oscillations, on these characteristics when they pass through the material. As the main parameter of the information ultrasonic signal, the time of its passage from the radiating to the receiving ultrasonic transducers is used. The amplitude of the information ultrasonic signal to a large extent depends on the structure of the investigated material, its acoustic resistance. At significant violations of the structure of the material there is a significant decrease in the amplitude of the information signal, which causes an increase in the error of measuring the time of its passage, and hence the definition of characteristics, quality of the investigated material. The article describes the developed method of increasing the accuracy of measuring the time of passage of the ultrasonic signal from the radiating to the receiving ultrasonic transducers. The essence of the technique is to use the mathematical modeling of the shape of the ultrasound signal, in particular the form of its so-called «first introduction».

To the Problems of Determination of Dynamic Elasticity Modules of Calcium Silicate Bricks by Means of Resonance Method

2014 ◽  
Vol 897 ◽  
pp. 139-143 ◽  
Author(s):  
Jiří Brožovský ◽  
Ámos Dufka
Keyword(s):  
Modulus Of Elasticity ◽  
Calcium Silicate ◽  
Building Materials ◽  
Resonance Method ◽  
Pulse Method ◽  
Ultrasonic Pulse ◽  
Test Methods ◽  
Test Method ◽  
Resonance Test ◽  
Accuracy Of Measurement

Modulus of elasticity of building materials can be determined in a static way (loading in a press) or by means of non-destructive test methods (ultrasonic pulse method and resonance method); the parameter is most frequently determined for concrete and both methods of determining elasticity modulus are codified in Standards. Elasticity characteristics of calcium silicate bricks were determined by means of resonance test method. Because the shape of calcium silicate bricks (a block with oblong foot) is different from the shape of test specimens for concrete (usually blocks with square foot), expected frequencies for verification of accuracy of measurement by resonance method were determined. Moisture content of calcium silicate bricks (water absorbing capacity is up to 12-14%) has influence on the value of resonance frequency. Difference between dynamic Young's modulus of elasticity from fundamental longitudinal and transverse resonant frequency is on average 2.8%.

Recommendations for testing concrete by the ultrasonic pulse method

1969 ◽  
Vol 2 (4) ◽  
pp. 275-284 ◽  
Author(s):  
R. Jones ◽  
I. Fącąoaru
Keyword(s):  
Pulse Method ◽  
Ultrasonic Pulse

Ultrasonic Pulse Method - Influence of Internal Compressive Stress on Results of Testing Calcium Silicate Bricks

2016 ◽  
Vol 722 ◽  
pp. 260-266
Author(s):  
Jiří Brožovský
Keyword(s):  
Compressive Strength ◽  
Calcium Silicate ◽  
Pulse Method ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Ultimate Compressive Strength ◽  
Technical Literature ◽  
Theoretical Assumptions ◽  
Inner Tension

Measuring with ultrasonic pulse method is influenced by various factors, like loading in particular inner tension when material built in a construction is tested. The paper researches influence of inner tension (load) on testing of calcium silicate bricks with ultrasonic pulse method. Calcium silicate bricks were loaded with force corresponding to 0 % (unloaded test specimens), 10 %, 20 %, 50 %, 60 % of ultimate compressive strength with various content of humidity (dried samples, w=2 %, w=8 % and samples saturated with water). It was found that ultrasonic pulse velocity is not considerably influenced at load of 10% and 20% of ultimate strength of bricks. However, ultrasonic pulse velocity considerably decreases after loading at 50% and 60% of ultimate compressive strength. Most of theoretical assumptions concerning mentioned concrete stated in technical literature were confirmed, however, particular values were different because of differences between concrete and calcium silicate bricks.

Mechanical Properties of Cubic (U,Zr)O2

2018 ◽  
Vol 4 (3) ◽  
Author(s):  
Toru Kitagaki ◽  
Takanori Hoshino ◽  
Kimihiko Yano ◽  
Nobuo Okamura ◽  
Hiroshi Ohara ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Elastic Modulus ◽  
Nuclear Power ◽  
Ultrasonic Pulse ◽  
Zro2 Content ◽  
Debris Removal ◽  
Working Principle ◽  
Water Reactors ◽  
Pulse Echo

Evaluation of fuel debris properties in the Fukushima Daiichi nuclear power plant (1F) is required to develop fuel debris removal tools. In the removal of debris resulting from the Three Mile Island unit 2 (TMI-2) accident, a core-boring system played an important role. Considering the working principle of core boring, hardness, elastic modulus, and fracture toughness were found to be important fuel debris properties that profoundly influenced the performance of the boring machine. It is speculated that uranium and zirconium oxide solid solution (U,Zr)O2 is one of the major materials in the fuel debris from 1F. In addition, the Zr content of the fuel debris from 1F is expected to be higher than that of the debris from TMI-2 because the 1F reactors were boiling-water reactors. In this research, the mechanical properties of cubic (U,Zr)O2 samples containing 10%–65% ZrO2 are evaluated. The hardness, elastic modulus, and fracture toughness are measured by the Vickers test, ultrasonic pulse echo method, and indentation fracture method, respectively. In the case of (U,Zr)O2 samples containing less than 50% ZrO2, Vickers hardness and fracture toughness increased, and the elastic modulus decreased slightly with increasing ZrO2 content. Moreover, all of those values of the (U,Zr)O2 samples containing 65% ZrO2 increased slightly compared to (U,Zr)O2 samples containing 55% ZrO2. ZrO2 content affects fracture toughness significantly in the case of samples containing less than 10% ZrO2. Higher Zr content (exceeding 50%) has little effect on the mechanical properties.

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