Rebound Hammer Tests of High-Strength Concrete: Effects of Internal Stress and the Shape of the Impact Area of the Test Specimens on the Measurement Results

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26110%2F19%3APU131145" target="_blank" >RIV/00216305:26110/19:PU131145 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/61989100:27120/19:10242867

Výsledek na webu

<a href="http://dx.doi.org/10.3311/PPci.11966" target="_blank" >http://dx.doi.org/10.3311/PPci.11966</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3311/PPci.11966" target="_blank" >10.3311/PPci.11966</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Rebound Hammer Tests of High-Strength Concrete: Effects of Internal Stress and the Shape of the Impact Area of the Test Specimens on the Measurement Results

Popis výsledku v původním jazyce

This study examines the factors affecting the results of non-destructive testing of high-strength concrete performed on cubes and on cylinders and examines the processing of calibration relations. Tests were performed with both a type N and a type L Schmidt impact hammer (with a standard impact energy of 2.205 Nm and 0.735 Nm respectively). The assessed factors were internal stress in a specimen and the shape of the impact area. Test specimens were loaded by a force corresponding to the stress in specimen 0%, 10%, 20%, 30%, and 50% from the expected compressive strength. Rebound numbers of the unloaded test specimens were significantly lower than those of the loaded specimens. Therefore, calibration relations and/or correction coefficients processed by measurements of unloaded specimens can be assessed as unsuitable. To process calibration relations, we recommend exerting internal stress in amounts of 15% to 20% of the expected compressive strength of the tested HSC samples. During the determination of the effect of the shape of the test area on the cylindrical test specimen, it was assumed that the rebound numbers on the plane and the round test area would be the same. However, the test results revealed that the rebound numbers in the differently shaped test areas were different. For Schmidt impact hammer type N, the rebound numbers in the round test area were lower by 0.7 units on average, and for Schmidt impact hammer type L, the rebound numbers in the round test area were lower by 1.7 units on average compared to the plane test area rebound numbers.

Název v anglickém jazyce

Rebound Hammer Tests of High-Strength Concrete: Effects of Internal Stress and the Shape of the Impact Area of the Test Specimens on the Measurement Results

Popis výsledku anglicky

This study examines the factors affecting the results of non-destructive testing of high-strength concrete performed on cubes and on cylinders and examines the processing of calibration relations. Tests were performed with both a type N and a type L Schmidt impact hammer (with a standard impact energy of 2.205 Nm and 0.735 Nm respectively). The assessed factors were internal stress in a specimen and the shape of the impact area. Test specimens were loaded by a force corresponding to the stress in specimen 0%, 10%, 20%, 30%, and 50% from the expected compressive strength. Rebound numbers of the unloaded test specimens were significantly lower than those of the loaded specimens. Therefore, calibration relations and/or correction coefficients processed by measurements of unloaded specimens can be assessed as unsuitable. To process calibration relations, we recommend exerting internal stress in amounts of 15% to 20% of the expected compressive strength of the tested HSC samples. During the determination of the effect of the shape of the test area on the cylindrical test specimen, it was assumed that the rebound numbers on the plane and the round test area would be the same. However, the test results revealed that the rebound numbers in the differently shaped test areas were different. For Schmidt impact hammer type N, the rebound numbers in the round test area were lower by 0.7 units on average, and for Schmidt impact hammer type L, the rebound numbers in the round test area were lower by 1.7 units on average compared to the plane test area rebound numbers.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20501 - Materials engineering

Projekt

<a href="/cs/project/GA15-23219S" target="_blank" >GA15-23219S: Studium metod dispergace nanočástic, stanovení podmínek zamezení jejich opětovného shlukování pro aplikaci v cementových kompozitech</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Periodica Polytechnica - Civil Engineering

ISSN

0553-6626

e-ISSN

—

Svazek periodika

63

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

HU - Maďarsko

Počet stran výsledku

7

Strana od-do

215-221

Kód UT WoS článku

000459904100022

EID výsledku v databázi Scopus

2-s2.0-85065097956