Prediction of elastic modulus of
concrete through using ultrasonic
pulse velocity
Journal Name:
- Dicle Üniversitesi Mühendislik Fakültesi Mühendislik Dergisi
Keywords (Original Language):
Author Name | University of Author | Faculty of Author |
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Abstract (2. Language):
Since seismicity is active in Turkey, most of the
buildings are vulnerable against earthquake
excitation. So, inspections of buildings are vital.
Concrete is one of the most important parameter
effect the performance of the building. Obtaining
mechanical properties of concrete is also one of the
most challenges in inspection of the building.
Obtaining elastic modulus of concrete is also one of
the most challenging since it requires sophisticated
measuring system. Classical technique which
require taking a piece of concrete for compression
testing causes more labor, time and costs. So a
simple method required especially in case of quick
inspection of the building.
Ultrasonic pulse velocity is one of the well known
techniques for a nun destructive evaluation of
concrete. The technique is easy, fast and requires
less labor. However it is not reliably by itself. In
order to increase the reliability, match curve must
be prepared for every different concrete type. So,
this study intended to develop a model for concrete
used especially in Diyarbakir district.
This study both includes experimental and empirical
work. In the experimental part eleven cylinder
specimens were produced from concrete work of
different stories of a building being retrofitted in
Diyarbakir. Dimension of cylinders are 150 mm in
diameter and 300 mm in height. All the specimens
were cured 28 days in water and tested after at least
28 days. Ultrasonic pulse velocity (UPV) tests were
carried out at first. For each specimen UPV tests
were carried out at five different points and UPV
values for each specimen was evaluated as average
of these five values. After UPV tests compression
tests were carried out for all specimen. For
compression tests, monotonically axial load was
increased until failure and the load and deformation
values were noted for each load increment.
After all the UPV and compression tests were
carried obtained data were used for developing a
model to predict elastic modulus of concrete from
UPV values. In model developing regression
analysis was utilized. Data analyzed to obtained
reasonable relation between UPV and elastic
modulus. As a result an equation was developed
(Equation 1). As seen in Equation 1 only UPV
values required to predict elastic modulus of
inspected concrete.
Ec=46.311×UPV-169.77 (1)
In these equations UPV and Ec values must be in
km/s and GPa units, respectively.
The last part of this study is the performances
evaluation of constructed model. To check
prediction performance of the model a bunch of data
was collected from literature. All of our data was
not used in the performance evaluation to make an
objective evaluation. Totally 19 data was used in
performance evaluation.
All the data are of normal concrete and of cylinder
specimens. To reach a comment for necessity of our
equations, a comparison was made between our
equations and few equations from literature.
Statistical parameters such as average and relative
error were used in performance check. For the best
model average of predicted and experimental
compressive strength should be nearest one and
relative error should smallest. Statistical evaluation
parameters for all models are given as follow,The above table clearly showed that relative error is
smallest and Average is closest to one for Equation
1. So, we can conclude that for the data grope was
used, equation 1 is the best in prediction of the
elastic modulus from UPV.
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Abstract (Original Language):
Betonun en önemli mekanik özelliklerinden olan elastisite modülünün hasarlı yöntemlerle tespiti oldukça
zahmetli bir iştir. Bu çalışmada betonun elastisite modülünün daha pratik bir şekilde belirlenmesi için
hasarsız yöntemlerden olan ultra ses dalgası kullanılmıştır. Bu amaçla beton silindir numuneler üretilerek
bu numuneler üzerinde hem ultra ses dalgası geçiş hızı ve basınç testleri yapılmıştır. Bu deneysel veriler
kullanılarak elastisite modülünün tahmini için ses dalgası geçiş hızına bağlı olan bir model geliştirilmiştir.
Bu çalışmada geliştirilen model literatürdeki mevcut modeller ve veriler ile karşılaştırıldığında tahmin
performansının iyi olduğu görülmüştür.
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