Impact Echo Q-Factor Measurements Towards Non-Destructive Quality Control of the Backfill in Segmental Lined Tunnels

2011 ◽  
pp. 915-919 ◽  
Author(s):  
N. Ryden ◽  
O. Aurell ◽  
P. Nilsson ◽  
J. Hartlén
Keyword(s):  
Quality Control ◽  
Q Factor ◽  
Impact Echo ◽  
Non Destructive

scholarly journals Moisture Measurement in Paper and Cardboard Packaging Waste Bales for Recycling

2021 ◽  
Vol 11 (10) ◽  
pp. 4586
Author(s):  
Ana Silveira ◽  
João Cardoso ◽  
Maria José Correia ◽  
Graça Martinho
Keyword(s):  
Quality Control ◽  
Dielectric Properties ◽  
Moisture Content ◽  
Reliable Method ◽  
Drying Method ◽  
Waste Streams ◽  
Oven Drying ◽  
Quality Issue ◽  
Commercial Device ◽  
Non Destructive

Moisture content is a quality issue raised by recycling plants in the acceptance of paper and cardboard coming from waste streams. The current way to measure this parameter is by the oven drying method, which is a slow and invasive process, costing time and resources for the recyclers to do this type of quality control. An alternative to such a measurement technique is the use of plate-form devices which indirectly measure the moisture content using the dielectric properties of water and paper. This study has tested this method and developed a representative equation for the use of devices with these properties in the Portuguese market. For that, 48 wastepaper and cardboard bales were tested with both the traditional (oven drying) method and a commercial device equipped with dielectric technology. An equation that fits the studied reality (R2 = 0.76) was achieved, and possible problems regarding the use of this device were tested. The results showed that this type of device could be used as a time- and cost-saving, non-destructive and reliable method in the quality control of wastepaper and cardboard bales.

Non-Destructive Identification of Defects in Power Support Structure Foundations by Means of Acoustic Techniques

2014 ◽  
Vol 606 ◽  
pp. 95-98
Author(s):  
Lukasz Sadowski
Keyword(s):  
Construction Industry ◽  
Support Structure ◽  
Air Voids ◽  
Impact Echo ◽  
Acoustic Techniques ◽  
Location Depth ◽  
Concrete Elements ◽  
Non Destructive ◽  
Made In

Prefabricated power support structure foundations are made in prefabrication plants where concrete is laid in layers in moulds. The quality of the prefabricated units depends mainly on proper concrete mixture compaction, which is usually effected by means of immersion vibrators. It happens that when the vibrator is withdrawn too quickly, defects, in the form of, e.g., air voids and zones of insufficiently vibrated concrete, appear. Modern non-destructive acoustic techniques, which in recent years have been increasingly commonly used in the construction industry, are highly suitable for testing concrete elements, particularly prefabricated concrete units. The non-destructive impact-echo technique is particularly useful for determining defect location depth and for locating defective areas.

Multispectral UV imaging for fast and non-destructive quality control of chemical and physical tablet attributes

2016 ◽  
Vol 90 ◽  
pp. 85-95 ◽  
Author(s):  
Marten Klukkert ◽  
Jian X. Wu ◽  
Jukka Rantanen ◽  
Jens M. Carstensen ◽  
Thomas Rades ◽  
...  
Keyword(s):  
Quality Control ◽  
Uv Imaging ◽  
Non Destructive

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.

Review on the Development of Non-Destructive Testing Based on Laser Ultrasonic Technique

2014 ◽  
Author(s):  
Yuanfeng He ◽  
Wenwu Zhang
Keyword(s):  
Quality Control ◽  
Optical Method ◽  
Vibration Signal ◽  
Quality Inspection ◽  
Ultrasonic Technique ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Laser Ultrasonic ◽  
Ultrasonic Technology ◽  
Non Destructive

Development of industry demands better performance of equipments and devices than ever. The property of material used to produce the equipments is the precondition to ensure the quality. As equipments are usually required to be integral during the quality inspection, non-destructive testing (NDT) plays an increasingly import role in modern industry quality control. Different NDT methods are introduced and analyzed. The mechanism of ultrasonic exciting is described. After the ultrasonic is excited, the vibration signal can be detected by transducer or optical method which are then illustrated. In the section of development of laser ultrasonic technology, contributions made by various researchers in theoretic development, experiment, simulation and application are introduced and the corresponding content of the researches as well. The conclusion and the outlook of laser ultrasonic technique is made at the last.

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.

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