Evaluation of the Electrical Resistivity, Ultrasonic Pulse Velocity and Mechanical Properties in Portland Cement Pastes Type II

2020 ◽  
Vol 841 ◽  
pp. 198-202
Author(s):  
Judith Alejandra Velázquez Perez ◽  
Elia Mercedes Alonso Guzmán ◽  
Wilfrido Martínez Molina ◽  
Hugo Luis Chávez García ◽  
Ioscany Talingo Moreno ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Electrical Resistivity ◽  
Portland Cement ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Type Ii ◽  
Cement Pastes ◽  
Cementing Material ◽  
Non Destructive

This research is focused on cement pastes with w/c ratio of 0.5. The cementing material is Portland cement type II. The main aim is to estimate the mechanical properties based on non-destructive tests such as ultrasonic pulse velocity, and electrical resistivity by a correlation with the destructive tests such as compressive strength, flexural strength, and tensile strength at ages of 3,7,14,21,28 and 45 days. The results suggest that there is a good correlation between evaluated properties.

scholarly journals Factors influencing ultrasonic pulse velocity in concrete

2020 ◽  
Vol 13 (2) ◽  
pp. 222-247 ◽  
Author(s):  
J. P. GODINHO ◽  
T. F. DE SOUZA JÚNIOR ◽  
M. H. F. MEDEIROS ◽  
M. S. A SILVA
Keyword(s):  
Portland Cement ◽  
Concrete Strength ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Hydrated Calcium Silicate ◽  
Degree Of Hydration ◽  
Mix Proportion ◽  
Non Destructive ◽  
Cylindrical Test

Abstract The hydration process of Portland cement triggers reactions of stabilization of minerals from the contact of the clinker with water, which is the Hydrated Calcium Silicate (C-S-H), the Etringite (3CaO.Al2O3.3CaSO4.32H2O) and the Portlandite (Ca(OH)2). In order to understand the effects of the evolution of hydration in cement, it is possible to apply non-destructive tests. In this context, the objective of this work is to evaluate the influence of the type of cement, the curing age, of the format and humidity of the test specimens of concrete in the ultrasonic pulse velocity (UPV). In order to do that, 36 cylindrical test specimens (10 x 20 cm) and 9 cubic ones with 25 cm of edges, with mix proportion of 1:2,7:3,2 (cement/sand/gravel), water/cement ratio of 0.58 and three types of Portland cement (CP II-Z-32, CP IV-32 RS and CP V-ARI) were molded. With data obtained it was possible to correlate the increase of concrete strength along time (at ages of 7, 14, 28, 70 and 91 days) with the increase of the ultrasonic pulse velocity. Besides, it was possible to prove the direct influence of the concrete moisture and of the degree of hydration in the UPV. The shape of the test specimen generally had no influence on the results, except in the case of cement CP V ARI.

Predictability of concrete damage level by non-destructive test methods

2021 ◽  
Vol 12 (4) ◽  
pp. 138
Author(s):  
Boğaçhan Akça ◽  
Süleyman Bahadır Keskin ◽  
Aysu Göçügenci
Keyword(s):  
Electrical Resistivity ◽  
Resonance Frequency ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Test Methods ◽  
Pulse Velocity ◽  
Frequency Method ◽  
Damage Level ◽  
Non Destructive ◽  
Destructive Methods

Non-destructive methods have many advantages over traditional test methods, especially since it does not damage the specimen, it can be used multiple times on the same specimen. These advantages also provide a great benefit in terms of following the property development in concrete as the same specimens are used which eliminates the variations related to the specimens. In this study, it is aimed to determine the damaged amount of concrete produced with different binders by electrical bulk resistivity, resonance frequency, and ultrasonic pulse velocity methods. Firstly, concretes containing different binders were produced, and along with the mechanical properties, ultrasonic wave velocity, resonance frequency, and electrical resistivity values of the produced concrete were determined at the 7, 28, and 90 days. Besides, the specimens were subjected to gradually increase compressive loads and non-destructive methods were used to estimate the extent of damage on specimens. It was attempted to establish a relationship between the damage on concrete specimens and the results obtained by non-destructive methods. Consequently, the compressive strength, electrical resistivity, ultrasonic pulse velocity and resonance frequency values of all specimens increased with the advancing age. It was concluded that the resonant frequency method is more successful than other methods in estimating the amount of damage in concrete.

Natural Additive to Retard the Setting of a Mortar and Increase its Resistance

2020 ◽  
Vol 841 ◽  
pp. 119-123
Author(s):  
Noel Díaz González ◽  
Luis Alberto González Luna ◽  
Elia Mercedes Alonso Guzmán ◽  
Wilfrido Martínez Molina ◽  
Hugo Luis Chávez García ◽  
...  
Keyword(s):  
Electrical Resistivity ◽  
Setting Time ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Cement Matrix ◽  
Simple Compression ◽  
Non Destructive ◽  
Natural Additive ◽  
Density Results

The use of better materials is essential for the development of a country, that is why in this work we analyze a mixture of cement-based mortar with an addition of mucilage from a plant called Maralfalfa, said plant is used as feed for cattle and it is thought that its hydrate content can improve the water-cement reaction. Two mixtures were made, one control and another with the addition. The material used was: volcanic sand from Michoacán, cement CPC 30R RS, drinking water and the addition of mucilage. Cubic specimens (5x5x5 cm), prismatic specimens (4x4x16 cm) and briquettes were made, which were tested at 7, 14, 21, 28, 45 and 70 days of age. The tests performed were non-destructive (density, ultrasonic pulse rate and electrical resistivity) and destructive (simple compression, flexion and tension). The density results indicate that the mixture with addition densifies the cement matrix, the ultrasonic pulse velocity results are very similar between the mixtures, the results of electrical resistivity indicate that the control mixture is slightly higher. In terms of simple compression and flexion, it is indicated that the mixture with the addition was higher than the control, whereas the voltage results indicate the opposite. In addition, it was found that the addition retards the setting time of the mixture.

scholarly journals ANALISIS PENURUNAN KUALITAS MUTU KAYU PADA BANGUNAN CAGAR BUDAYA DENGAN METODE NON DESTRUCTIVE TEST (Studi Kasus Bangunan Cagar Budaya Masjid Gedhe Mataram Daerah Istimewa Yogyakarta)

2020 ◽  
Vol 16 (2) ◽  
pp. 191-199
Author(s):  
Darmono Darmono ◽  
Maris Setyo Nugroho ◽  
Slamet Widodo ◽  
Faqih Ma’arif
Keyword(s):  
Mechanical Properties ◽  
Cultural Heritage ◽  
Field Testing ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Test Results ◽  
Destructive Test ◽  
The Difference ◽  
Non Destructive

ABSTRAKPenelitian bertujuan untuk mengetahui mechanical properties material kayu Bangunan Cagar Budaya dengan non-destructive test. Penelitian ini menggunakan metode pengujian lansung dilapang menggunakan Ultrasonic Pulse Velocity (UPV). Terdapat dua variable yang digunakan yaitu kolom cacat dan kolom utuh untuk mengetahui perbedaan nilai cepat rambat gelombang. Jumlah sampel yang digunakan sebanyak enam buah dengan pengambilan data masing-masing sampel sebanyak lima kali. Hasil pengujian menunjukkan bahwa nilai kadar air dan berat jenis kayu sebesar 15,03% dan 0,62. Sedangkan hasil pengujian UPV pada kolom cacat dan utuh diperoleh cepat rambat gelombang sebesar 0,71 km/s dan 1,21 km/s. Berdasarkan hasil analisis menunjukkan bahwa nilai MOEd pada kolom utuh sebesar 9.374,37 MPa, sedangkan MOEd pada kolom cacat sebesar 3.240,62 MPa. Kata kunci: mechanical properties kayu, bangunan cagar budaya, ultrasonic pulse velocity ABSTRACTThis study aims to determine the mechanical properties of the wood material for the Cultural Heritage Building with a non-destructive test. This study used a direct field testing method using Ultrasonic Pulse Velocity (UPV). There are two variables used, namely the defective column and the solid column to determine the difference in the value of the fast propagation of the waves. The number of samples used was six with data collection for each sample five times. The test results showed that the moisture content and density of wood were 15.03% and 0.62. While the UPV test results on defective and solid columns obtained wave propagation velocity of 0.71 km / s and 1.21 km / s. Based on the analysis result, it shows that the MOEd value in the whole column is 9,374.37 MPa, while the MOEd in the defective column is 3,240.62 MPa. Keywords: mechanical properties of wood, cultural heritage buildings, ultrasonic pulse velocity

scholarly journals Behavior of blended cement pastes at elevated temperature

2006 ◽  
Vol 12 (2) ◽  
pp. 133-136
Author(s):  
G. Kakali ◽  
R. Leventi ◽  
V. Benekis ◽  
S. Tsivilis
Keyword(s):  
Portland Cement ◽  
Fire Resistance ◽  
Elevated Temperatures ◽  
Blended Cement ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Building Structures ◽  
Cement Pastes ◽  
Blended Cements

Fire can cause severe damage to building structures. This fact has increased the importance of the fire resistance of concrete. The consideration of the fire resistance of concrete requires the complete knowledge of the behaviour of each concrete component under elevated temperatures. The resistance of blended cement pastes upon heating was studied in the present paper. Natural pozzolana, fly ash, ground granulated blast-furnace slag, metakaolin and limestone were used as the main cement constituents. Blended cements were prepared by replacing a part of Portland Cement (PC) with the minerals mentioned above (10% w/w in the case of metakaolin, 20% w/w in the case of the rest materials). The specimens were water-cured for 3 months and then they were thermally treated at 200, 400, 600 800 and 1000?C for 1h. Visual inspection, mass measurements and ultrasonic pulse velocity measurements were carried out after each thermal treatment. It was concluded that the cohesion of the pastes was strongly affected by the kind of the main constituent, added to the Portland cement. The use of pozzolanic materials and especially metakaolin improved the fire resistance of the pastes, while the samples with limestone show the worst behavior.

Destructive and non-destructive testing of bronze-waste tire-concrete composites

2020 ◽  
Vol 11 (1) ◽  
pp. 11
Author(s):  
Tuba Bahtlı ◽  
Nesibe Sevde Özbay
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Test Methods ◽  
Pulse Velocity ◽  
Destructive Testing ◽  
Waste Tire ◽  
Schmidt Rebound Hammer ◽  
Non Destructive

In this study, the effects of finely-milled bronze and waste tire on the mechanical properties of concrete have been investigated. Approximately 2.5% and 5% by weight for each additive (bronze sawdust and waste tire) were added to dry concrete. The open porosity, density, compressive strength values of cured concrete have been determined. In addition, the Schmidt rebound hammer (SRH) and the ultrasonic pulse velocity (UPV) tests, which are non-destructive test methods, were applied. The microstructure and fracture surfaces of these materials were characterized by scanning electron microscopy (SEM). It was observed that the density of pure concrete was 2.35 g/cm3 while the density was 2.19 g/cm3 for a C+5%B+5%T material. Similarly, pure concrete had an almost three times better compressive strength and a two times better SRH value than those of the C+5%B+5%T material. The density and mechanical properties of concrete materials containing bronze and waste tire decreased due to micro crack formations, weak bonding and deep cracks forming especially between the concrete and additives.

scholarly journals Properties of Portland Cement Mortar with Substitutions of Natural and Expanded Perlite

2018 ◽  
Author(s):  
Mauricio Arreola Sánchez ◽  
Wilfrido Martínez Molina ◽  
Hugo Luis Chávez García ◽  
Elia Mercedes Alonso Guzmán ◽  
Andrés A. Torres Acosta ◽  
...  
Keyword(s):  
Portland Cement ◽  
Cement Mortar ◽  
Total Porosity ◽  
Ultrasonic Pulse Velocity ◽  
Ultrasonic Pulse ◽  
Pulse Velocity ◽  
Partial Replacement ◽  
Expanded Perlite ◽  
Hardened State ◽  
Non Destructive

The present research deals with the feasibility of using high-temperature pozzolans such as Natural Perlite (NP) and Expanded Perlite (EP), different dosagues of additions were made to mortars in order to perform their mechanical properties. Mortars were subjected to destructive tests in hardened state: compression, tension, flexion and adhesion strength; as well as non-destructive tests in hardened state: ultrasonic pulse velocity (UPV), electrical resistivity (ER), density (ρ) and total porosity (PT); in addition to attack by sodium sulfate at 90 days. The percentages of the substitutions were 5%, 10%, 15%, 20% and 30% by weight of Portland cement mass (PC) relative to a control mortar (cement-sand-water). With the partial replacement of the cement and according to the tests carried out, it can be observed that the problem of durability and CO2 emissions is significantly reduced and, consequently, an energy saving and a lower environmental impact are promoted.

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