Bituminous mixtures - Test methods - Part 44: Crack propagation by semi-circular bending test

This document specifies the Semi-Circular Bending (SCB) test method to determine the tensile strength or fracture toughness of an asphalt mixture for the assessment of the potential for crack propagation. The results of the test can be used to calculate:
- the maximum load that the material containing a notch (crack) can resist before failure;
- when the presence of a notch is critical.
It should be noted that the test only describes a method to determine the resistance to crack propagation of an asphalt mixture. The crack propagation phase describes the second part of failure mechanism during dynamic loading. The first phase, which is the crack initiation phase, is mainly covered by the fatigue test (EN 12697-24).

Asphalt - Prüfverfahren - Teil 44: Bestimmung der Rissausbreitung mittels Halbzylinder-Biegeversuch

Dieses Dokument legt das Verfahren zur Messung der Rissausbreitung mittels Halbzylinder-Biegeversuch (en: Semi-Circular Bending (SCB)) zur Bestimmung der Zugfestigkeit oder Bruchzähigkeit von Asphaltgemischen zur Beurteilung ihres Risswachstumspotentials fest.
Die Ergebnisse dieser Prüfung können für Folgendes verwendet werden:
—   zur Berechnung der Höchstlast, der ein mit einer Kerbe (Riss) versehenes Material, ohne zu reißen, standhalten kann;
—   für Berechnungen, in denen das Vorhandensein einer Kerbe kritisch ist.
Es sollte beachtet werden, dass diese Prüfung nur ein Verfahren zur Bestimmung des Widerstandes von Asphaltgemischen gegen Risswachstum beschreibt. Die Risswachstumsphase beschreibt den zweiten Teil des Ausfallprozesses bei dynamischer Belastung. Die erste Phase, d. h. die Rissentstehungsphase, wird in erster Linie durch die Ermüdungsprüfung abgedeckt (siehe EN 12697 24).

Mélanges bitumineux - Méthodes d'essai - Partie 44 : Propagation de fissure par essai de flexion d'un bloc semi-circulaire

Ce document décrit la méthode d’essai de flexion d’un bloc semi-circulaire (SCB) permettant de déterminer la résistance à la traction ou la ténacité à la rupture d’un mélange bitumineux pour l’évaluation du potentiel de propagation de fissure. Les résultats de l’essai peuvent servir à déterminer :
—   la charge maximale que peut supporter un matériau présentant une entaille (fissure) avant de se rompre ;
—   si la présence d’une entaille est critique ou non.
Il convient de noter que l’essai décrit seulement une méthode de détermination de la résistance à la propagation de fissure d’un mélange bitumineux. La phase de propagation de fissure correspond à la seconde partie du mécanisme de rupture sous une charge dynamique. La première phase, c’est-à-dire la phase d’initiation de la fissure, est principalement traitée par l’essai de fatigue (voir l’EN 12697 24).

Bitumenske zmesi - Preskusne metode - 44. del: Širjenje razpoke s polkrožnim upogibnim preskusom

Ta osnutek evropskega standarda določa preskusno metodo s polkrožnim upogibnim preskusom (SCB) za ugotavljanje natezne trdnosti ali odpornosti asfaltne zmesi proti lomljenju za ocenjevanje možnosti širjenja razpoke. Rezultati preskusa se lahko uporabijo za izračun:
–   največje obremenitve, ki jo še lahko prenese material z zarezo (razpoko);
–   tega, kdaj je prisotnost zareze kritična.
Opozoriti je treba, da preskus opisuje zgolj metodo za ugotavljanje odpornosti na širjenje razpoke asfaltne zmesi. Faza širjenja razpoke opisuje drugi del mehanizma okvare pri dinamični obremenitvi. Prva faza, tj. faza uvajanja razpoke, je v glavnem zajeta v preskusu utrujenosti (EN 12697-24).

General Information

Status
Published
Publication Date
05-Mar-2019
Withdrawal Date
29-Sep-2019
Technical Committee
CEN/TC 227 - Road materials
Current Stage
9060 - Closure of 2 Year Review Enquiry - Review Enquiry
Start Date
02-Sep-2024
Completion Date
02-Sep-2024

Relations

Effective Date
08-Jun-2022

Overview - EN 12697-44:2019 (SCB test for bituminous mixtures)

EN 12697-44:2019 is a CEN standard that specifies the Semi‑Circular Bending (SCB) test method for bituminous mixtures (asphalt). The method determines tensile strength or fracture toughness of an asphalt mixture to assess its susceptibility to crack propagation. Results allow calculation of the maximum load a notched specimen can resist (Fmax) and whether a notch (pre‑existing crack) is critical for failure. The test focuses on the crack propagation phase of failure; crack initiation is mainly covered by EN 12697‑24 (fatigue testing).

Key topics and technical requirements

  • Test principle: a half‑cylinder (semi‑circular) specimen with a centre notch is loaded in three‑point bending so tensile stress occurs at the base; deformation is applied at a constant rate and the maximum load (Fmax) is recorded.
  • Specimen and notches:
    • Height tolerance added: (74 ± 1) mm.
    • Notch width tolerance: (0.40 ± 0.20) mm.
  • Loading and rates:
    • Constant displacement rate of (5.0 ± 0.2) mm/min during the test.
  • Apparatus accuracy:
    • Test machine range at least 50 kN.
    • Load measurement accuracy ±0.2 kN.
    • Displacement measurement accuracy ±0.01 mm.
    • Roller support geometry: centre‑to‑centre support length (120.0 ± 0.5) mm, roller diameter (35.0 ± 0.5) mm.
  • Measured quantities and outputs:
    • Maximum force (Fmax), tensile strength, fracture toughness (KIc, unit N/mm1.5), strain and stress at failure.
  • Test scope: method for resistance to crack propagation only; not a full fatigue initiation assessment.

Applications - who uses EN 12697-44:2019

  • Pavement materials laboratories for mix characterization and quality control.
  • Road and pavement engineers for mixture design and selection of crack‑resistant asphalt.
  • Contractors and QA/QC teams for acceptance testing and verification of production mixes.
  • Research organizations and universities studying fracture mechanics, asphalt crack propagation, or comparing binder/aggregate effects.
  • Forensic investigations of pavement distress to quantify propagation resistance.

Practical benefits include objective comparison of mixes, support for specification limits, and data for modelling crack growth in pavements.

Related standards

  • EN 12697‑24 - Fatigue test (crack initiation phase)
  • EN 12697‑27 - Sampling
  • EN 12697‑31 - Specimen preparation by gyratory compactor
  • EN 12697‑33 - Specimen prepared by roller compactor
  • EN 12697‑35 - Laboratory mixing

Keywords: EN 12697-44:2019, SCB test, semi‑circular bending test, bituminous mixtures, asphalt fracture toughness, crack propagation, pavement materials, tensile strength, CEN.

Frequently Asked Questions

EN 12697-44:2019 is a standard published by the European Committee for Standardization (CEN). Its full title is "Bituminous mixtures - Test methods - Part 44: Crack propagation by semi-circular bending test". This standard covers: This document specifies the Semi-Circular Bending (SCB) test method to determine the tensile strength or fracture toughness of an asphalt mixture for the assessment of the potential for crack propagation. The results of the test can be used to calculate: - the maximum load that the material containing a notch (crack) can resist before failure; - when the presence of a notch is critical. It should be noted that the test only describes a method to determine the resistance to crack propagation of an asphalt mixture. The crack propagation phase describes the second part of failure mechanism during dynamic loading. The first phase, which is the crack initiation phase, is mainly covered by the fatigue test (EN 12697-24).

This document specifies the Semi-Circular Bending (SCB) test method to determine the tensile strength or fracture toughness of an asphalt mixture for the assessment of the potential for crack propagation. The results of the test can be used to calculate: - the maximum load that the material containing a notch (crack) can resist before failure; - when the presence of a notch is critical. It should be noted that the test only describes a method to determine the resistance to crack propagation of an asphalt mixture. The crack propagation phase describes the second part of failure mechanism during dynamic loading. The first phase, which is the crack initiation phase, is mainly covered by the fatigue test (EN 12697-24).

EN 12697-44:2019 is classified under the following ICS (International Classification for Standards) categories: 93.080.20 - Road construction materials. The ICS classification helps identify the subject area and facilitates finding related standards.

EN 12697-44:2019 has the following relationships with other standards: It is inter standard links to EN 12697-44:2010. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.

You can purchase EN 12697-44:2019 directly from iTeh Standards. The document is available in PDF format and is delivered instantly after payment. Add the standard to your cart and complete the secure checkout process. iTeh Standards is an authorized distributor of CEN standards.

Standards Content (Sample)


2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Bitumenske zmesi - Preskusne metode - 44. del: Širjenje razpoke s polkrožnim upogibnim preskusomAsphalt - Prüfverfahren - Teil 44: Bestimmung der Rissausbreitung mittels Halbzylinder-BiegeversuchMélanges bitumineux - Méthodes d'essai - Partie 44 : Propagation de fissure par essai de flexion d'un bloc semi-circulaireBituminous mixtures - Test methods - Part 44: Crack propagation by semi-circular bending test93.080.20Materiali za gradnjo cestRoad construction materialsICS:Ta slovenski standard je istoveten z:EN 12697-44:2019SIST EN 12697-44:2019en,fr,de01-maj-2019SIST EN 12697-44:2019SLOVENSKI
STANDARDSIST EN 12697-44:20101DGRPHãþD

EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 12697-44
March
t r s { ICS
{ uä r z rä t r Supersedes EN
s t x { yæ v vã t r s rEnglish Version
Bituminous mixtures æ Test methods æ Part
v vã Crack propagation by semiæcircular bending test Mélanges bitumineux æ Méthodes d 5essai æ Partie
v v ã Propagation de fissure par essai de flexion d 5un bloc semiæcirculaire
Asphalt æ Prüfverfahren æ Teil
v vã Bestimmung der Rissausbreitung mittels HalbzylinderæBiegeversuch This European Standard was approved by CEN on
s { November
t r s zä
egulations which stipulate the conditions for giving this European Standard the status of a national standard without any alterationä Upætoædate lists and bibliographical references concerning such national standards may be obtained on application to the CENæCENELEC Management Centre or to any CEN memberä
translation under the responsibility of a CEN member into its own language and notified to the CENæCENELEC Management Centre has the same status as the official versionsä
CEN members are the national standards bodies of Austriaá Belgiumá Bulgariaá Croatiaá Cyprusá Czech Republicá Denmarká Estoniaá Finlandá Former Yugoslav Republic of Macedoniaá Franceá Germanyá Greeceá Hungaryá Icelandá Irelandá Italyá Latviaá Lithuaniaá Luxembourgá Maltaá Netherlandsá Norwayá Polandá Portugalá Romaniaá Serbiaá Slovakiaá Sloveniaá Spainá Swedená Switzerlandá Turkey and United Kingdomä
EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre:
Rue de la Science 23,
B-1040 Brussels
t r s { CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Membersä Refä Noä EN
s t x { yæ v vã t r s { ESIST EN 12697-44:2019
...

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기사 제목 : EN 12697-44:2019 - 비트로믹스 - 시험 방법 - 제 44부: 반원형 굽힘 시험을 통한 균열 전파 기사 내용 : 본 문서는 균열 전파 가능성의 평가를 위해 아스팔트 혼합물의 인장 강도 또는 파괴 강도를 결정하는 반원형 굽힘(SCB) 시험 방법을 명시한다. 시험 결과는 다음과 같은 계산에 사용될 수 있다: - 노치(균열)를 가진 물질이 실패하기 전에 견디는 최대 하중 - 노치의 존재가 중요한 때 이 시험은 아스팔트 혼합물의 균열 전파 저항력을 결정하기 위한 방법을 제시하는 것에 주목해야 한다. 균열 전파 단계는 동적 하중 조건에서 실패 메커니즘의 두 번째 부분을 설명한다. 첫 번째 단계인 균열 생성 단계는 주로 피로 시험 (EN 12697-24)으로 다루어진다는 것을 알아두어야 한다.

記事のタイトル:EN 12697-44:2019 - ビチュミナスミックス - 試験方法 - 第44部: 半円形曲げ試験によるクラック伝播 記事の内容:この文書は、アスファルトミックスの応力強度または破壊靭性を評価するための半円形曲げ(SCB)試験方法を定めています。試験の結果は、以下の計算に利用できます: - クラック(ノッチ)を含む材料が破壊する前に耐えることができる最大荷重 - ノッチの存在が重要になる時期 ただし、この試験方法はアスファルトミックスのクラック伝播耐性を評価する方法についてのみ説明しており、クラック発生の最初の段階であるクラック発生フェーズについては、主に疲労試験(EN 12697-24)で評価されています。

The article discusses the EN 12697-44:2019 standard, which outlines a test method called Semi-Circular Bending (SCB) to assess the tensile strength and fracture toughness of asphalt mixtures. The SCB test can determine the maximum load that a material with a crack can withstand before failing, and it can also determine when the presence of a crack becomes critical. However, it is essential to note that the test method only focuses on evaluating the resistance to crack propagation and does not cover the crack initiation phase, which is analyzed in the fatigue test described in the EN 12697-24 standard.