An Initial Investigation on the Potential Applicability of Non-Destructive Methods to Assessing Joint Condition in Prefabricated Structures

2016 ◽  
Vol 258 ◽  
pp. 489-492
Author(s):  
Monika Manychova ◽  
Ondřej Fuciman ◽  
Lubos Pazdera
Keyword(s):  
Physical Models ◽  
Impact Echo ◽  
Joint Condition ◽  
Load Models ◽  
Potential Applicability ◽  
Foundation Base ◽  
Application Potential ◽  
Stress States ◽  
The Impact ◽  
Non Destructive

Prefabricated structures have brought quite a new quality into the design of building construction method, which in turn required deeper theoretical knowledge, replacing empirical approaches by theory, replacing idealized and often simplified models of structure behaviour by accurate material physical models and load models. High rigidity of prefabricated concrete structures and the resulting stress states, which are mainly due to the volume change effects (temperature, humidity), effects of the foundation base shape variations etc., are among the most frequent causes of failures, particularly of joints of building elements featuring insufficient yield and bearing capacity. Investigation of all prefabricated building types shows progressing joint armature corrosion, considerable impairment of welds, which should secure the positional reliability of façade slabs.The paper presents some results of our experimental study of the application potential of the impact-echo method to the non-destructive assessment of the present joint condition in prefabricated structures.

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.

scholarly journals Grouting Performance Evaluation of the Double Injection Method for Settlement Restoration of Concrete Rail Tracks

2020 ◽  
Vol 20 (6) ◽  
pp. 31-38
Author(s):  
Hyo Seog Koh ◽  
Byong Jeong Choi
Keyword(s):  
Field Tests ◽  
Type Method ◽  
Impact Echo ◽  
Double Injection ◽  
Value Recovery ◽  
Investigation Methods ◽  
Injection Type ◽  
Restoration Method ◽  
The Impact ◽  
Non Destructive

For the construction of concrete tracks, strict settling control standards are applied. However, settlement inevitably occurs owing to the construction conditions, climate, and geographical conditions. When settlement occurs beyond the limited value, recovery work is performed by using a restoration method. During restoration processes, the concrete track must maintain its support stiffness and not develop non-uniform stress to ensure proper functioning of interface systems between the track and roadbed and geometric settlement recovery. To satisfy these conditions, the track must be tightly filled to prevent voids from occurring at the bottom. This paper proposes a double-injection-type method for cement grouting to secure filling, considering the injection material, pressure, and interval. In this study, the filling performance was evaluated through field tests using visual inspection and the impact echo technique, which are non-destructive investigation methods.

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.

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.

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.

Peculiarities of tool material wear at polymeric composite blank cutting

2018 ◽  
Vol 2018 (7) ◽  
pp. 27-31
Author(s):  
Юрий Зубарев ◽  
Yuriy Zubarev ◽  
Александр Приемышев ◽  
Alexsandr Priyomyshev
Keyword(s):  
Tool Wear ◽  
Tool Material ◽  
Polymeric Composite ◽  
Physical Models ◽  
Technological Parameters ◽  
Tool Materials ◽  
Materials Used ◽  
The Impact ◽  
Material Wear

Tool materials used for polymeric composite blank machining, kinds of tool material wear arising at machining these blanks, and also the impact of technological parameters upon tool wear are considered. The obtained results allow estimating the potentialities of physical models at polymeric composite blanks cutting.

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