The Use of Acoustic Methods for Non-Destructive Testing of High-Temperature-Degraded Cement-Based Composite

2013 ◽  
Vol 446-447 ◽  
pp. 1395-1399 ◽  
Author(s):  
Zdeněk Chobola ◽  
Daniela Štefková ◽  
Kristýna Šamárková
Keyword(s):  
High Temperature ◽  
Acoustic Method ◽  
Temperature Treatment ◽  
High Temperature Treatment ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Impact Echo ◽  
Flexural Tensile Strength ◽  
Acoustic Methods ◽  
Non Destructive

The present paper deals with the applicability of Impact-echo acoustic method to testing of cement-based composites prepared from a mix of cement mortar and quartz sand, which were intentionally degraded by high-temperature treatment (in the temperatures range from 200°C to 1200°C). Changes in the the bulk density and the flexural tensile strength were monitored during the degradation for comparison.

High-Temperature Degradation of Mortar Containing Rubber Aggregates and EVA Binder Evaluated by Impact-Echo Method

2014 ◽  
Vol 627 ◽  
pp. 272-275 ◽  
Author(s):  
Daniela Štefková ◽  
Michael Tupý ◽  
Konstantinos Sotiriadis ◽  
Kristýna Šamárková ◽  
Zdeněk Chobola
Keyword(s):  
High Temperature ◽  
Acoustic Method ◽  
Temperature Treatment ◽  
Polymer Binder ◽  
High Temperature Treatment ◽  
Destructive Testing ◽  
Impact Echo ◽  
Acoustic Methods ◽  
Reference Specimens ◽  
Rubber Aggregates

The application of Impact-echo acoustic method to evaluate the degradation and the composition of mortar composites modified with rubber aggregates and EVA polymer binder degraded at high temperatures was studied. Specimens were prepared by using a type CEM I Portland cement and siliceous sand, as well as by substituting 25% of sand with shredded automobile tires and by adding of EVA polymer binder (10% w/w to cement mass). The samples were subjected to high-temperature treatment in the temperature range of 200-400 °C. The results of non-destructive testing of such samples by acoustic methods confirmed the differences in the structure of mortar specimens. Addition of rubber aggregates in samples caused absorption of lower frequency as compared to reference specimens. A significant decrease of the absorbed frequencies was observed depending on the temperature. The largest decrease happened after exposure of samples at 200-300 °C. It indicates that the effect of heat treatment was reduced when the EVA binder was added.

Impact-Echo Method for Non-Destructive Testing of High-Temperature-Degraded Cement-Based Composite

2015 ◽  
Vol 1124 ◽  
pp. 301-306
Author(s):  
Daniela Štefková ◽  
Kristýna Timcakova ◽  
Zdeněk Chobola
Keyword(s):  
High Temperature ◽  
Acoustic Analysis ◽  
Heat Exposure ◽  
Acoustic Method ◽  
High Temperature Treatment ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Impact Echo ◽  
Non Destructive ◽  
Impact Echo Method

Non-destructive acoustic analysis method Impact-echo method as a traditional method for civil engineering was used for this experiment. The paper deals with the applicability of Impactecho acoustic method to testing of cement-based composites prepared from a mix of cement mortar and quartz sand, which were intentionally degraded by high-temperature treatment (in the temperatures range from 200°C to 1200°C). The aim of this paper is introduce the effect of high-temperature degradation. An understanding of microstructure performance relationships is the key to true understanding of material behaviors. The results of non-destructive testing confirmed the different structure of mortar specimens. The subjected to high-temperatures led to absorption of lower frequencies as compared to the reference specimens. A significant decrease of the absorbed frequencies was observed, depending on temperature. The largest decrease occurred after the specimens exposure at 400-600 °C. The effect of heat exposure to the decrease of frequencies was mitigated to the temperature degradation 1200 °C.

Use of Impact-Echo Method to Test High-Temperature Degraded Cementitious Composite Materials Containing Rubber Aggregates and Acrylic Polymer Binder

2014 ◽  
Vol 897 ◽  
pp. 238-241 ◽  
Author(s):  
Daniela Štefková ◽  
Michael Tupý ◽  
Kristýna Šamárková ◽  
Zdeněk Chobola ◽  
Konstantinos Sotiriadis ◽  
...  
Keyword(s):  
High Temperature ◽  
Acoustic Method ◽  
Temperature Treatment ◽  
Polymer Binder ◽  
High Temperature Treatment ◽  
Cementitious Composite ◽  
Acrylic Polymer ◽  
Impact Echo ◽  
Rubber Aggregates ◽  
Impact Echo Method

The present paper deals with the use of Impact-echo acoustic method to test cement-based mortar composites degraded at high temperatures. The specimens were prepared by using a type CEM I Portland cement and siliceous sand, as well as by substituting 25% of sand with shredded automobile tires and by adding acrylic polymer binder (20% w/w to cement mass). The samples were were subjected to high-temperature treatment in the temperature range of 200-400 °C. The acoustic results confirmed the differences in the structure of mortar specimens. The addition of rubber aggregates in H2 and H3 specimens resulted in lower frequencies compared to H1 specimen. It was also observed the dropping down of the frequencies for the temperatures between 200-300°C, indicating that the effect of heat treatment was mitigated when the acrylic binder was added.

Estimation of Thickness of Concrete Slab Members Using Impact Echo Method

2014 ◽  
Vol 605 ◽  
pp. 139-142
Author(s):  
Seong Uk Hong ◽  
Yong Taeg Lee ◽  
Seung Hun Kim ◽  
J.H. Na
Keyword(s):  
Concrete Slab ◽  
Hardness Test ◽  
Pulse Velocity ◽  
Non Destructive Testing ◽  
Testing Methods ◽  
Destructive Testing ◽  
Impact Echo ◽  
Maintenance And Repair ◽  
Non Destructive ◽  
Impact Echo Method

Recently, the interest in maintenance and repair of existing concrete structures have increased, and it is typical to use non-destructive testing methods such as rebound hardness test or ultrasonic pulse velocity method to execute maintenance and repair of structures efficiently. Many non-destructive testing methods are being used in practice such as at construction sites, but verification for site applications are quite inadequate. Thus, this study intends to evaluate the applicability of Impact Echo Method which is one of the non-destructive testing methods using stress wave. Total of four specimens were planned and produced. The thickness of concrete slab members was estimated using I.E(OLSENs Freedom Data PC with Win.TFS Software Version 2.5.2). The estimated materials of concrete members by IE was found to be IE-1 specimen 178mm, IE-2 specimen 197mm, IE-3 specimen 191mm, and IE-4 specimen 263mm, and the error rate was found to be 4.22%~18.67% (average 9.6%), showing that they are relatively well in agreement. In this study, the experiments were executed with the objective of estimating the thickness of concrete slab members using Impact Echo Method. Through this study, the applicability of thickness estimation in concrete slab members using impact echo method could be confirmed.

scholarly journals Increasing the laser-acoustic method efficiency for testing metal products by using 3D visualization

2019 ◽  
Vol 124 ◽  
pp. 03010
Author(s):  
I. R. Ismagilov ◽  
R. I. Kalimullin ◽  
A. N. Borisov
Keyword(s):  
Surface Defects ◽  
3D Visualization ◽  
Acoustic Method ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Testing Metal ◽  
Metal Products ◽  
Non Destructive

The article proposes a solution to the problem of increasing the efficiency of the laser-acoustic method of non-destructive testing. An approach to increasing the probability of detecting surface defects of microscopic dimensions in metals is considered. Due to the increased accuracy of determining defect parameters, the detail of 3D visualization of testing results was improved.

Influence of Water Content on Fundamental Frequency of Mortar Sample

2015 ◽  
Vol 1124 ◽  
pp. 273-279 ◽  
Author(s):  
Ladislav Carbol ◽  
Jan Martinek ◽  
Ivo Kusák
Keyword(s):  
Water Content ◽  
Fundamental Frequency ◽  
Non Destructive Testing ◽  
In Situ Testing ◽  
Mortar Sample ◽  
Destructive Testing ◽  
Impact Echo ◽  
Influence Of Water ◽  
Non Destructive

Ultrasonic non-destructive testing methods such as Impact-echo are often conducted under different conditions. Such results might be distorted by ambient temperature or by water content of the tested sample. Tested mortar sample displayed shift of the fundamental frequency by 3.7 %. This article confirms necessity of standardized conditions during ultrasonic testing for both laboratory and in-situ testing.

Estimation of Steel Rebar Position and Thickness in Concrete Members Using Impact Echo Method

2014 ◽  
Vol 605 ◽  
pp. 420-423
Author(s):  
Seong Uk Hong ◽  
Seung Hun Kim ◽  
Yong Taeg Lee
Keyword(s):  
Heterogeneous Material ◽  
Non Destructive Testing ◽  
Testing Methods ◽  
Destructive Testing ◽  
Impact Echo ◽  
Thickness Estimation ◽  
Steel Rebar ◽  
Concrete Members ◽  
Non Destructive ◽  
Impact Echo Method

Non-destructive testing methods, unlike typical destructive testing methods that deconstruct or cut the building in case of issues such as pores, heterogeneous material, cracks or any such equivalent issues inside/outside the building. And refer to the testing methods for pores, heterogeneous material, or defectiveness occurring in the specimen without changes or destruction of internal structure using ultrasound, radiation, electromagnetism, fluid, heat, or light. In this study, among such non-destructive testing methods, the impact echo method was used for an experiment to estimate the steel rebar location and thickness in the concrete mock member. The mix was made with design standard strength of 30MPa, and for the steel rebar, diameter 22mm was used on the specimen of 300×370×200 to install spacer on the ground surface, and after separating by 40mm, it was arranged with 130mm and 150mm from the top of the specimen to the top of the rebar in 1 column and 3 rows. The specimen for thickness estimation was manufactured with total length of 1800×300 and 6 varying thicknesses of 150mm, 180mm, 210mm, 240mm, 270mm, and 300mm. As the result of rebar location estimation, the maximum resonant frequency was found to be 11269Hz, 9453Hz,and the rebar location estimates were 127.8mm and 151.8mm, which was relatively accurate with error rate of 1.72% and 1.19% from the actual value. In case of thickness estimation specimen, the error rates comparing actually measured thickness and the average value were 2.2%, 2.2%, 4.6%, 0.9%, 3.8%, and 4.7%, which were relatively accurate with average of 3.1%. Through this study, the applicability of steel rebar location and thickness estimation in concrete members using impact echo method could be confirmed.

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