Experimental Analysis of the Development of Compressive Strength, Modulus of Elasticity and Acoustic Emission Parameters of Alkali-Activated Composites

2018 ◽  
Vol 760 ◽  
pp. 266-271
Author(s):  
Dalibor Kocáb ◽  
Libor Topolář ◽  
Vlastimil Bílek Jr. ◽  
Barbara Kucharczyková ◽  
Michaela Hoduláková ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Acoustic Emission ◽  
Modulus Of Elasticity ◽  
Stress Test ◽  
Ultrasonic Pulse ◽  
Static Modulus ◽  
Activated Slag ◽  
Static Modulus Of Elasticity ◽  
Non Destructive ◽  
Alkali Activated

This paper describes an experiment focused on monitoring the development of the modulus of elasticity and the compressive strength of composites that are based on alkali‑activated slag (AAS) during the first 28 days of ageing. The test specimens were tested at the age of 3 and 28 days using two non-destructive methods (ultrasonic pulse and resonance methods) to determine the value of the dynamic modulus of elasticity. Subsequently, the same specimens were used to determine the static modulus of elasticity using compressive stress test, during which the behaviour of the composite was monitored by equipment for recording the acoustic emission in the material. The result of the experiment is the evaluation of the behaviour of the AAS composite in regard to the development of its modulus of elasticity and compressive strength, as well as in regard to the acoustic emission method during loading.

scholarly journals Concrete Compressive Strength by Means of Ultrasonic Pulse Velocity and Moduli of Elasticity

Materials ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 7018
Author(s):  
Bogdan Bolborea ◽  
Cornelia Baera ◽  
Sorin Dan ◽  
Aurelian Gruin ◽  
Dumitru-Doru Burduhos-Nergis ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Modulus Of Elasticity ◽  
Pulse Velocity ◽  
High Rate ◽  
Dry Density ◽  
Concrete Compressive Strength ◽  
Static Modulus ◽  
Static Modulus Of Elasticity ◽  
Non Destructive ◽  
Moduli Of Elasticity

Developing non-destructive methods (NDT) that can deliver faster and more accurate results is an objective pursued by many researchers. The purpose of this paper is to present a new approach in predicting the concrete compressive strength through means of ultrasonic testing for non-destructive determination of the dynamic and static modulus of elasticity. For this study, the dynamic Poisson’s coefficient was assigned values provided by technical literature. Using ultra-sonic pulse velocity (UPV) the apparent density and the dynamic modulus of elasticity were determined. The viability of the theoretical approach proposed by Salman, used for the air-dry density determination (predicted density), was experimentally confirmed (measured density). The calculated accuracy of the Salman method ranged between 98 and 99% for all the four groups of specimens used in the study. Furthermore, the static modulus of elasticity was deducted through a linear relationship between the two moduli of elasticity. Finally, the concrete compressive strength was mathematically determined by using the previously mentioned parameters. The accuracy of the proposed method for concrete compressive strength assessment ranged between 92 and 94%. The precision was established with respect to the destructive testing of concrete cores. For this research, the experimental part was performed on concrete cores extracted from different elements of different structures and divided into four distinct groups. The high rate of accuracy in predicting the concrete compressive strength, provided by this study, exceeds 90% with respect to the reference, and makes this method suitable for further investigations related to both the optimization of the procedure and = the domain of applicability (in terms of structural aspects and concrete mix design, environmental conditions, etc.).

scholarly journals Influence of Hybrid Fibers on Toughness Behavior of High Strength Flowing Concrete

2011 ◽  
Vol 57 (3) ◽  
pp. 249-260 ◽  
Author(s):  
Eethar Thanon Dawood ◽  
Mahyuddin Ramli
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Modulus Of Elasticity ◽  
Hybrid Composite ◽  
High Strength ◽  
Steel Fibers ◽  
Hybrid Fibers ◽  
Static Modulus ◽  
Static Modulus Of Elasticity ◽  
Strength And Toughness

Abstract This study investigates the use of steel fibers and hybrid composite with a total fibers content of 2% on the high strength flowing concrete and determines the density, compressive strength, static modulus of elasticity, flexural strength and toughness indices for the mixes. The results show that the inclusion of more than 0.5% of palm fibers in hybrid fibers mixes reduces the compressive strength. The hybrid fibers can be considered as a promising concept and the replacement of a portion of steel fibers with palm fibers can significantly reduce the density, enhance the flexural strength and toughness. The results also indicates that the use of hybrid fibers (1.5 steel fibers + 0.5% palm fibers) in specimens increases significantly the toughness indices and thus the use of hybrid fibers combinations in reinforced concrete would enhance their flexural toughness & rigidity and enhance their overall performances

Non-Destructive Testing for Concrete: Dynamic Modulus and Ultrasonic Velocity Measurements

2011 ◽  
Vol 243-249 ◽  
pp. 165-169 ◽  
Author(s):  
Iqbal Khan Mohammad
Keyword(s):  
Compressive Strength ◽  
Modulus Of Elasticity ◽  
Dynamic Modulus ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Dynamic Modulus Of Elasticity ◽  
Non Destructive

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.

scholarly journals A Study on Initial Setting and Modulus of Elasticity of AAM Mortar Mixed with CSA Expansive Additive Using Ultrasonic Pulse Velocity

Materials ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 4432
Author(s):  
Gum-Sung Ryu ◽  
Sung Choi ◽  
Kyung-Taek Koh ◽  
Gi-Hong Ahn ◽  
Hyeong-Yeol Kim ◽  
...  
Keyword(s):  
Modulus Of Elasticity ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Static Modulus ◽  
Setting Times ◽  
Initial Setting ◽  
Expansive Additive ◽  
Static Modulus Of Elasticity ◽  
Initial Reactivity

This study investigated the hardening process of alkali-activated material (AAM) mortar using calcium sulfoalumiante (CSA) expansive additive (CSA EA), which accelerates the initial reactivity of AAMs, and subsequent changes in ultrasonic pulse velocity (UPV). After the AAM mortar was mixed with three different contents of CSA EA, the setting and modulus of elasticity of the mortar at one day of age, which represent curing steps, were measured. In addition, UPV was used to analyze each curing step. The initial and final setting times of the AAM mortar could be predicted by analyzing the UPV results measured for 14 h. In addition, the dynamic modulus of elasticity calculated using the UPV results for 24 h showed a tendency similar to that of the static modulus of elasticity. The test results showed that the use of CSA EA accelerated the setting of the AAM mortar and increased the modulus of elasticity, and these results could be inferred using UPV. The proposed measurement method can be effective in evaluating the properties of a material that accelerates the initial reactivity.

Influence of a Shrinkage-Reducing Admixture on the Damage to the Internal Structure of Alkali-Activated Composites during Testing of the Modulus of Elasticity

2018 ◽  
Vol 272 ◽  
pp. 28-33
Author(s):  
Dalibor Kocáb ◽  
Vlastimil Bílek Jr. ◽  
Libor Topolář ◽  
Petr Daněk ◽  
Barbara Kucharczyková ◽  
...  
Keyword(s):  
Internal Structure ◽  
Modulus Of Elasticity ◽  
Resonance Method ◽  
Ultrasonic Pulse Velocity ◽  
Pulse Velocity ◽  
Acoustic Activity ◽  
Static Modulus ◽  
Shrinkage Reducing Admixture ◽  
Static Modulus Of Elasticity ◽  
Alkali Activated

This article deals with an experimental determination of the static modulus of elasticity in compression on fine-grained composites based on alkali-activated slag. This experiment included an alkali-activated composite without a shrinkage-reducing admixture and the same composite with a shrinkage-reducing admixture. The test specimens were subjected to testing of the dynamic modulus of elasticity using the ultrasonic pulse velocity test and the resonance method as well as of the static modulus of elasticity in compression. The static modulus of elasticity test was accompanied by the measurement of the acoustic activity of the material using the acoustic emission method, whose advantages is the possibility to detect early formation and propagation of cracks in the internal structure of the material. The output of the described experiment is a detailed evaluation of the differences in the behaviour of the tested alkali-activated composites based on the observed values of the modulus of elasticity and the recorded acoustic activity of the material during loading.

scholarly journals Analysis of Measured Parameters in Relation to the Amount of Fibre in Lightweight Red Ceramic Waste Aggregate Concrete

Mathematics ◽  
2022 ◽  
Vol 10 (2) ◽  
pp. 229
Author(s):  
Marie Horňáková ◽  
Petr Lehner
Keyword(s):  
Modulus Of Elasticity ◽  
Test Methods ◽  
Fibre Reinforcement ◽  
Ceramic Waste ◽  
Destructive Test ◽  
Correlation And Regression Analysis ◽  
Regression Curves ◽  
Static Modulus ◽  
Static Modulus Of Elasticity ◽  
Non Destructive

The present study provides a correlation and regression analysis of lightweight waste aggregate concretes with varying degrees of fibre reinforcement. The concrete mix contains pre-soaked red ceramic waste aggregate, expanded clay coarse aggregate and Portland cement. Copper-coated crimped steel fibre was used as the reinforcement. The experimental results included properties measured by destructive test methods—compressive strength, splitting tensile strength, static modulus of elasticity, the limit of proportionality, shear strength; and by non-destructive test methods—dynamic modulus of elasticity and surface electrical resistivity. These properties were analysed to study the relevancy and significance between non-destructive and destructive methods of measurement in the case of different amounts of fibre. The results show differences in the degree of fit to the linear and quadratic regression curves for pairs of destructive and non-destructive test results. As expected, the linear relationship can be applied in a few cases, but the quadratic curve must be used for a few pairs. Another observation is that it is not possible to neglect the amount of fibre in the correlation analyses of the measured properties.

Sign in / Sign up

Export Citation Format

Share Document