scholarly journals Unstable behaviour of rocks

2009 ◽  
Vol 31 (3-4) ◽  
Author(s):  
Luong Minh Phong

This paper aims to introduce a new non-destructive testing technique in use for detecting the occurrence of material instability and a specific data reduction procedure to access damage accumulation. An input-output non-parametric procedure based on ultrasonic pulse propagation, and a non-linear analyser were chosen to portray the unstable behaviour of brittle rock material under static compressive loading. It can be used to monitor non-destructively and continuously the overall alteration or damage process so that damage mechanisms could be quantitatively estimated by a dimensionless parameter the so-called non-linearity ratio.

2011 ◽  
Vol 243-249 ◽  
pp. 165-169 ◽  
Author(s):  
Iqbal Khan Mohammad

Nondestructive testing (NDT) is a technique to determine the integrity of a material, component or structure. The commonly NDT methods used for the concrete are dynamic modulus of elasticity and ultrasonic pulse velocity. The dynamic modulus of elasticity of concrete is related to the structural stiffness and deformation process of concrete structures, and is highly sensitive to the cracking. The velocity of ultrasonic pulses travelling in a solid material depends on the density and elastic properties of that material. Non-destructive testing namely, dynamic modulus of elasticity and ultrasonic pulse velocity was measured for high strength concrete incorporating cementitious composites. Results of dynamic modulus of elasticity and ultrasonic pulse velocity are reported and their relationships with compressive strength are presented. It has been found that NDT is reasonably good and reliable tool to measure the property of concrete which also gives the fair indication of the compressive strength development.


2019 ◽  
Vol 970 ◽  
pp. 63-74
Author(s):  
Yuliya Shulgina ◽  
Maria A. Kostina ◽  
P.V. Sorokin ◽  
Marina Polonskaya ◽  
O.A. Kozhemyak ◽  
...  

Many industries apply pressure tanks for the storage of various types of liquids [1]. It can be toxic, chemically active liquids or food products. Storage conditions of these liquids can have a wide range of pressures and temperatures; therefore it is preferable to control the liquids levels from the outside of the tank. The most optimal solution in this case is the ultrasonic pulse time method [2-6], which is also widely used in robotics [7], fishing, shipping [8-9], archeology [10-11], non-destructive testing [12-17] and manometric method [18].


2018 ◽  
Vol 207 ◽  
pp. 01001
Author(s):  
Tu Quynh Loan Ngo ◽  
Yu-Ren Wang

In the construction industry, to evaluate the compressive strength of concrete, destructive and non-destructive testing methods are used. Non-destructive testing methods are preferable due to the fact that those methods do not destroy concrete samples. However, they usually give larger percentage of error than using destructive tests. Among the non-destructive testing methods, the ultrasonic pulse velocity test is the popular one because it is economic and very simple in operation. Using the ultrasonic pulse velocity test gives 20% MAPE more than using destructive tests. This paper aims to improve the ultrasonic pulse velocity test results in estimating the compressive strength of concrete using the help of artificial intelligent. To establish a better prediction model for the ultrasonic pulse velocity test, data collected from 312 cylinder of concrete samples are used to develop and validate the model. The research results provide valuable information when using the ultrasonic pulse velocity tests to the inputs data in addition with support vector machine by learning algorithms, and the actual compressive strengths are set as the target output data to train the model. The results show that both MAPEs for the linear and nonlinear regression models are 11.17% and 17.66% respectively. The MAPE for the support vector machine models is 11.02%. These research results can provide valuable information when using the ultrasonic pulse velocity test to estimate the compressive strength of concrete.


2018 ◽  
Vol 792 ◽  
pp. 166-169
Author(s):  
Yu Ren Wang ◽  
Loan T.Q. Ngo ◽  
Yi Fan Shih ◽  
Yen Ling Lu ◽  
Yi Ming Chen

SONREB method is a non-destructive testing (NDT) method for estimating the concrete compressive strength. It is conducted by combining two popular NDT methods: ultrasonic pulse velocity (UPV) test and rebound hammer (RH) test. Several researches have been attempted to find the correlation of the different testing method data with actual compressive strength. This research proposes a new Artificial Intelligence based approach, Artificial Neural Networks (ANNs), to estimate the concrete compressive strength using the UPV and RH test data. Data from a total of 315 cylinder concrete samples are collected to develop and validate the ANFIS prediction model. The model prediction results are compared with actual compressive strength using mean absolute percentage error (MAPE). With the adaption of ANFIS, the estimation error of SONREB test can be reduced to 5.98% (measured by MAPE).


2021 ◽  
Vol 1197 (1) ◽  
pp. 012054
Author(s):  
Ragini Kondalkar ◽  
Nikhil H. Pitale ◽  
K.R. Dabhekar ◽  
D.P. Mase

Abstract In India there are infinite old structures that are at the verge of damages. There are many buildings which have reduced their strength due to time passes, due to deterioration of concrete from structural element, due to development of cracks. The structure is a combination of load carrying members, damages in members cause failure of structure and it is harmful for living beings. To prevent old structure from failure the technique is adopted know as Non-Destructive Testing (NDT). With the help of non-destructive testing auditing of an old structure is get easier. NDT examine the total health of an infrastructure in order to check strength and stability of building. NDT is a bunch of various testing consist of Ultrasonic pulse velocity test (UPV), Rebound hammer test (RHT), Half-cell test, etc. Conducting NDT on building and analyzing testing result decide to repair building as per IS code, technique like grouting, Retrofitting, etc. to increase strength and stability of building. In this project structural has to be done on old structure which is situated at Nagpur. Audit done by NDT consist of Ultra-sonic pulse velocity test, Rebound hammer test, Half-cell test. After analyzing all test result including visual inspection it is found that structure need to repair and retrofitted to make it safe and stable for all static loadings. Column jacketing also provide to structure.


2016 ◽  
Vol 827 ◽  
pp. 324-327
Author(s):  
Pavel Reiterman ◽  
Ondřej Holčapek

Present paper is focused on the experimental assessment of three sandstones from different quarries. Mechanical testing was carried out besides water absorption test and determination of frost resistance what is the crucial material parameter for all types of porous rocks. Gradual deterioration due to action of frost was monitored using non-destructive testing – ultrasonic pulse method. Obtained results well describe failure mechanism of studied sandstones of different basic physical properties. It was conducted that main part of deterioration was performed at the beginning of the freeze-thaw cycling.


2021 ◽  
Vol 45 (5) ◽  
pp. 361-368
Author(s):  
Messaouda Belouadah ◽  
Zine Elabidine Rahmouni ◽  
Nadia Tebbal ◽  
Mokrani El Hassen Hicham

The present study aims primarily to investigate the possibility of assessing the physico-mechanical behavior of concrete incorporating marble waste or marble powder as a partial replacement for cement using destructive and non-destructive testing methods. Indeed, in this work, cement was partially replaced with marble powder at six different substitution levels, i.e. 5, 10, 15, 20, 25 and 30% by weight, with 1.5% adjuvant (super plasticizer) for each mixture. The samples prepared were then analyzed. In addition, the physico-mechanical properties, in the fresh and hardened states, water-to-cement ratio, absorption and compressive strengths of the concrete samples were examined as well. Moreover, the compressive strength of concrete was assessed through non-destructive testing methods such as the ultrasonic pulse velocity and rebound hammer. Likewise, the relationship between the ultrasound velocity and compressive strength of concrete were also estimated after 3, 7, 28 and 90 days of curing. The findings of the study indicated that, at early age of curing, the values of the compressive strength and ultrasonic pulse velocity were quite small for all replacement levels, of cement with marble powder, between 15 and 30%. Nevertheless, when the curing period was increased, the compressive strength and ultrasonic pulse velocity of all the samples went up as well. In the end, a linear relationship was observed between the ultrasonic pulse velocity and compressive strength for all substitution levels of cement with marble powder.


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