NDT Monitoring of Alkali-Activated Material Carbonation

2020 ◽  
Vol 868 ◽  
pp. 45-50
Author(s):  
Iveta Plšková ◽  
Michal Matysík ◽  
Libor Topolář ◽  
Petr Hrubý
Keyword(s):  
Portland Cement ◽  
Raw Materials ◽  
Ultrasound Velocity ◽  
Degradation Process ◽  
Dominant Frequency ◽  
Impact Echo ◽  
The Impact ◽  
Non Destructive ◽  
Impact Echo Method ◽  
Alkali Activated

Production of Portland cement is relatively environmentally demanding (high CO2 emissions, extraction of raw materials for its production). Alkali-activated materials are an alternative to conventional Portland cement in the production of concrete. For alkali-activated binder concretes, their ability to withstand corrosive environments and their ability to protect steel reinforcement must be assessed. It is also necessary to know the suitability of non-destructive methods for monitoring the degradation process of these concretes. The paper deals with the carbonation monitoring of concrete with alkali-activated binder (slag) by the impact-echo method. Slag activated by sodium hydroxide (NaOH) was used as a binder. The specimens were tested by the non-destructive method (Impact-echo, ultrasound velocity). We focused on the shift of the dominant frequency obtained by the Impact-echo method.

Estimation of Depth of Concrete Column Members Using Impact Echo Method

2014 ◽  
Vol 605 ◽  
pp. 194-197
Author(s):  
Seung Hun Kim ◽  
Seong Uk Hong ◽  
Yong Taeg Lee ◽  
Seung Ho Lee
Keyword(s):  
Test Methods ◽  
Test Method ◽  
Concrete Column ◽  
Ground Field ◽  
Design Strength ◽  
Impact Echo ◽  
Destructive Test ◽  
The Impact ◽  
Non Destructive ◽  
Impact Echo Method

In order to maintain the existing concrete structures in a safe and usable state, an overall maintenance management is necessary regarding structure aging from quality management of new construction. Thus, non-destructive testing is needed to estimate the structure damage, defect, or proper construction without damaging the structure. In U.S., there is a standard for non-destructive test (ACI 228.2R-98), and also in Japan, the non-destructive test method and compressive strength estimation manual was prepared by the Architectural Institute of Japan in 1983, and there are active researches in the ground field, but it lacks verification in architecture field. Thus, in this study, a technique that can estimate the depth of concrete column member using the Impact Echo method which is one of the non-destructive test methods shall be reviewed and evaluated for applicability to the architecture field. The specimen was mixed with design strength of 30MPa. The equipment used in testing is Freedom Date Pc Platform Win.TFS 2.5.2 by company Olson of U.S., and the experiment involved leveling the top surface of the concrete member, installing the equipment and applying impact 9 times, and taking the average of the reverberation values obtained. The estimated average depth of concrete column member using Impact Echo method was 304mm for IEC-300, 398mm for IEC-400, and 484mm for IEC-500, and the relative error rate compared to the actual size was 1%~3%. Through this study, the applicability of estimation of depth in concrete column members using impact echo method could be confirmed.

Characterization of Carbonatation Rate of Alkali-Activated Blast Furnace Slag in Various Environments

2021 ◽  
Vol 325 ◽  
pp. 40-46
Author(s):  
Richard Dvořák ◽  
Petr Hrubý ◽  
Libor Topolář
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Destructive Testing ◽  
Time Intervals ◽  
Impact Echo ◽  
The Impact ◽  
Non Destructive ◽  
Furnace Slag ◽  
Alkali Activated

Carbonatation represents one of the potential degradation processes whose can negatively affect the service life of constructions based on the inorganic binders. The carbonatation depth of the constructions when exposed to various environments is significantly dependent on the existing conditions. The most crucial parameters are the partial pressure of carbon dioxide and humidity. There were selected four environments for the deposition of samples made of the alkali-activated blast furnace slag mortars (exterior, interior, water and CO2 chamber) in this study. These types of environments guarantee the variation of desired parameters influencing the carbonatation rate. The progress of carbonatation was evaluated with a selected technique in time intervals of 28; 56 and 84 days of the sample's exposition to the selected environments. The characterization was done using the destructive techniques (compressive and flexural strength, phenolphthalein method) as well as the non-destructive one like the Impact-Echo or the Ultrasound time passage measurement. The combination of these techniques allows to determine and evaluate the progress of carbonation without the destructive testing of the samples which is necessary for the real applications of these materials.

Application of Impact-Echo Method in Grouting Inspection in Ducts inside Prefabricated Box Girder

2014 ◽  
Vol 505-506 ◽  
pp. 24-27 ◽  
Author(s):  
Cun Zhi Kong ◽  
Xiang Feng Xu ◽  
Jia Long Sun ◽  
Guang Zhi Qi ◽  
Yuan Cao
Keyword(s):  
Basic Principle ◽  
Bridge Engineering ◽  
Quality Inspection ◽  
Box Girder ◽  
Impact Echo ◽  
Post Tensioning ◽  
The Impact ◽  
Non Destructive ◽  
Impact Echo Method

Based on basic principle of detection using impact-echo method, in combination with urgent demand of grouting quality inspection in ducts inside post tensioning type prefabricated box girder in bridge engineering, impact-echo method has been used for non-destructive detection of grouting compactness in pre-stressed ducts inside prefabricated box girder. Verification by beating away measuring points shows that the impact-echo method can accurately locate metal corrugated pipes and qualitatively judge grouting compactness inside prefabricated box girder ducts, to allow effective inspection of grouting quality in strands of pre-stressed ducts.

The Influence of Curing and Process of Hydration to Damping Coefficient of Alkali Activated Slag Mortars

2015 ◽  
Vol 1100 ◽  
pp. 21-24
Author(s):  
Kristýna Timcakova ◽  
Libor Topolář ◽  
Peter Rypák
Keyword(s):  
Acoustic Analysis ◽  
Drying Shrinkage ◽  
Analysis Method ◽  
Impact Echo ◽  
Alkali Activated Slag ◽  
Activated Slag ◽  
High Level ◽  
Non Destructive ◽  
Impact Echo Method ◽  
Alkali Activated

Non-destructive acoustic analysis method Impact-echo method as a traditional for civil engineering was used for experiment. This paper reports the experiment during hardening and drying of specimens of alkali activated slag mortars. Alkali activated slag is a material having a great potential to be used in practice. The main drawback of this material is a high level of autogenous and especially drying shrinkage, which causes a deterioration of the mechanical properties. The aim of this paper is introduce the effect of method curing of mortars and time curing on the microstructure of alkali activated slag mortars. An understanding of microstructure performance relationships is the key to true understanding of material behaviours.

Numerical Simulation of Impact-Echo Method Identify the Depth of Honeycomb Damage in Unballasted Track

2014 ◽  
Vol 584-586 ◽  
pp. 2060-2067 ◽  
Author(s):  
Chang Sheng Zhou ◽  
Ping Wang ◽  
Zhi Peng Hu ◽  
Hao Zhu
Keyword(s):  
High Speed ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Impact Echo ◽  
Finite Element Software ◽  
Ballastless Track ◽  
The Impact ◽  
Non Destructive ◽  
Impact Echo Method ◽  
Peak Value

Through the honeycomb damage that is appear in unballasted track will affect the safe operation of high-speed train, accurate detection of honeycomb damage is very important. Impact-echo method is a non-destructive testing method. Based on the principle of impact echo, author using the finite element software ANSYS LS-DYNA3D to simulate the impact-echo, testing and verifying the feasibility and accuracy of impact-echo method in discerning unballasted track damage. By analyzing the calculated result of honeycomb damage in slab track and double-block ballastless track, it is shows that: according to back calculate the depth of damage base on the peak value in acceleration spectrum graph, the honeycomb damage in different depth can be accurate located.

A Study on the Diagnosis Method of Concrete Structures of School Buildings Using Non-Destructive Tests Based on Stress Waves

2006 ◽  
Vol 321-323 ◽  
pp. 400-403
Author(s):  
Young S. Cho ◽  
Han Seung Lee
Keyword(s):  
Structural Information ◽  
Flaw Detection ◽  
Concrete Structures ◽  
School Facilities ◽  
School Buildings ◽  
Existing Building ◽  
Impact Echo ◽  
The Impact ◽  
Non Destructive ◽  
Impact Echo Method

As most of the elementary, junior high, and high school buildings nationwide have been deteriorated since the quantitative increase of the buildings from 1985, many experts present the issues on the possibility of the structural instability of the building as well as the increase of the cost for maintenance of the building. So, it is necessary to examine the necessary structural information of the school buildings during the course of maintaining education facilities, and it is also necessary to establish some credible accessing procedures on the deteriorating school facilities so that the building structural engineers can propose the necessary standards for the proper maintenance and repairing works. To achieve the necessity, researches have been conducted to find out the ways of diagnosing the compressive strength and the durability of the concrete structures by measuring the compression wave velocity of concrete structures and the flaw detection inside the concrete specimens using the impact echo method, a non-destructive test to simulate the structures of school buildings. In this research, it was found that the impact echo method has great potentials in the application of the building structure maintenance and the repairing activities based on the accurate understanding of the existing school facilities that are being deteriorated. More over, school facilities has sometimes no structural design drawings available which NDT methods can contribute to detect the internal structural damages of existing building structures.

Detecting the Defects in Concrete Components with Impact-Echo Method

2014 ◽  
Vol 577 ◽  
pp. 1114-1118 ◽  
Author(s):  
Jing Liu ◽  
Jun Xie ◽  
Xiao Yu He ◽  
Yu Shan He ◽  
Jia Hui Zhong
Keyword(s):  
Prestressed Concrete ◽  
Large Scale ◽  
Concrete Block ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Impact Echo ◽  
The Impact ◽  
Non Destructive ◽  
Impact Echo Method

With the large-scale application of the prestressed concrete structure, the quality of the concrete component defects and pipeline grouting has increasingly become the focus of attention. The impact-echo scanner uses the nature of wave, which pass though different media at different velocities, to distinguish internal defects of concrete, pipe filling density and so on. In this paper, using the impact-echo method to detect the concrete block with prefabricated defects of shape, location, and size explores the effect of defect properties, parameter settings and detection environment to impact-echo preliminarily and also explores the relationship of pipeline filling status and impact-echo image. Based on this study, the article raised the problem met during this non-destructive testing methods applied to engineering, and accumulated a certain amount of available engineering data. The experiment results show that using the impact-echo method to identify the defects of concrete components and to test the quality of pipeline grouting is a more convenient and effective non-destructive testing method. Especially, with the radar method in the pipeline grouting quality inspection which complement each other to make up for the shortcomings the lightning wave in case of the metal medium total reflection phenomenon, cannot detect metal pipe grouting plumpness.

Estimation of Impact-Echo Method for the Assessment of Long-Term Frost Resistance of Ceramic Tiles

2014 ◽  
Vol 1000 ◽  
pp. 285-288 ◽  
Author(s):  
Michal Matysík ◽  
Iveta Plšková ◽  
Zdeněk Chobola
Keyword(s):  
Frost Resistance ◽  
Surface Condition ◽  
Acoustic Method ◽  
Ceramic Tiles ◽  
Impact Echo ◽  
Thaw Cycle ◽  
Freeze Thaw Cycle ◽  
Confocal Scanning ◽  
The Impact ◽  
Impact Echo Method

The aim of this paper is to evaluate the possibility of using the Impact-echo method for assessment of extremely long period of frost resistance of ceramic tiles. Sets of ceramic tiles of the Ia class to EN 14 411 B standard made by manufacture RACOs have been analyzed. The ceramic tiles under investigation have been subjected to 500 freeze-thaw-cycle based degradation in compliance with the relevant EN ISO 10545-12 standard. To verify the correctness of the Impact-echo method results, additional physical properties of the ceramic tiles under test have been measured. To analyze the specimen surface condition, we also used Olympus LEXT 3100 confocal scanning microscope. It has been proved that the acoustic method Impact-echo is a sensitive indicator of the structure condition and can be applied to the ceramic cladding element frost resistance and service life prediction assessment.

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.

Sign in / Sign up

Export Citation Format

Share Document