Name: aggregate size testing with sieve grading
Uploaded: 2024-11-07T14:48:25.000Z
Duration: 1 min 19 s
Channel: JoVE

L’analyse par tamis des agrégats est effectuée à l’aide d’un ensemble de tamis empilés par ordre décroissant de leur taille d’ouverture, de haut en bas.
 La taille des tamis varie pour les granulats grossiers et les granulats fins.
Un échantillon d’agrégats séchés à l’air est pesé et tamisé à travers les tamis, soit en les secouant mécaniquement, soit manuellement pendant un temps spécifié.
Au cours du processus, chaque tamis retient les particules plus grossières que sa taille de maille tout en permettant aux particules plus fines de passer au tamis suivant.
Le poids des fractions retenues sur chaque tamis est enregistré, exprimé en pourcentage de la masse totale, et représenté dans un tableau.
En partant du tamis le plus fin et en remontant, le pourcentage cumulé passant par chaque tamis est calculé et arrondi au 1 pour cent le plus proche.
De plus, un graphique semi-logarithmique est utilisé pour représenter le pourcentage de passage sur l’axe des y et les ouvertures du tamis sur l’axe des x à l’échelle logarithmique.
Sur ce graphique, le pourcentage de passage cumulé correspondant à chaque taille de tamis est tracé pour obtenir la courbe de classement, qui indique la distribution des particules agrégées en fonction de leur taille.

analyse par tamisage et courbes de granulométrie

L'analyse par tamisage est une méthode utilisée pour déterminer la distribution granulométrique des matériaux agrégés. Ce processus comprend les étapes suivantes :

<ol style="padding-left: 35px; margin: 0;">
 <li>
 La quantité requise d’échantillon séché d’agrégat est pesée.
 </li>
 <li>
 Les agrégats pesés sont tamisés à travers un ensemble de tamis à ouvertures carrées disposés par ordre décroissant de taille d'ouverture, avec la plus grande maille en haut (colonne 1 du tableau 1).
 </li>
 <li>
 La pile de tamis est secouée ou agitée pour faciliter le tri des particules par taille.
 </li>
 <li>
 Après un tamisage pendant une période déterminée, le matériau retenu sur chaque tamis est pesé (colonne 2 du tableau 1).
 </li>
 <li>
 Le poids des particules retenues sur chaque tamis est exprimé en pourcentage de la masse totale de l’échantillon (colonne 3 du tableau 1).
 <img alt="Equation1" src="/files/ftp_upload/16871/16871%20_Equation_PT_001v2.svg" style="height: 46px;">
 </li>
 <li>
 Le pourcentage cumulé passant à travers chaque tamis est calculé au pour cent le plus proche à partir du tamis le plus fin en remontant (colonne 4 du tableau 1).
 </li>
 <li>
 La courbe de granulométrie est tracée sur un graphique (Figure 1) où les valeurs d'ordonnées représentent le pourcentage de passage (colonne 4 du tableau 1) et les valeurs d'abscisses montrent les ouvertures du tamis (colonne 1 du tableau 1), réglées sur une échelle logarithmique.
 </li>
</ol>

Tableau 1 : Données pour l'analyse par tamisage pour le sable

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
 <tr>
 <td style="text-align: center;">Colonne 1</td>
 <td style="text-align: center;">Colonne 2</td>
 <td style="text-align: center;">Colonne 3</td>
 <td style="text-align: center;">Colonne 4</td>
 </tr>
 <tr>
 <td style="text-align: center;">Tamis ASTM (Taille du tamis)</td>
 <td style="text-align: center;">Poids retenusur chaque tamis (g)</td>
 <td style="text-align: center;">Pourcentage de poidsretenu sur chaque tamis (%)</td>
 <td style="text-align: center;">Pourcentage cumulé passant chaque tamis (%)</td>
 </tr>
 <tr>
 <td style="text-align: center;">⅜ pouce (9,5 mm)</td>
 <td style="text-align: center;">0</td>
 <td style="text-align: center;">0</td>
 <td style="text-align: center;">98+2 = 100</td>
 </tr>
 <tr>
 <td style="text-align: center;">N° 4 (4,75 mm)</td>
 <td style="text-align: center;">10</td>
 <td style="text-align: center;">2</td>
 <td style="text-align: center;">88+10 = 98</td>
 </tr>
 <tr>
 <td style="text-align: center;">N° 8 (2,36 mm)</td>
 <td style="text-align: center;">50</td>
 <td style="text-align: center;">10</td>
 <td style="text-align: center;">79+9 = 88</td>
 </tr>
 <tr>
 <td style="text-align: center;">N° 16 (1,18 mm)</td>
 <td style="text-align: center;">45</td>
 <td style="text-align: center;">9</td>
 <td style="text-align: center;">61+18 = 79</td>
 </tr>
 <tr>
 <td style="text-align: center;">N°30 (600µ)</td>
 <td style="text-align: center;">90</td>
 <td style="text-align: center;">18</td>
 <td style="text-align: center;">29+32 = 61</td>
 </tr>
 <tr>
 <td style="text-align: center;">N°50 (300µ)</td>
 <td style="text-align: center;">160</td>
 <td style="text-align: center;">32</td>
 <td style="text-align: center;">10+19 = 29</td>
 </tr>
 <tr>
 <td style="text-align: center;">N° 100 (150µ)</td>
 <td style="text-align: center;">95</td>
 <td style="text-align: center;">19</td>
 <td style="text-align: center;">10</td>
 </tr>
 <tr>
 <td style="text-align: center;">Bac inférieur</td>
 <td style="text-align: center;">50</td>
 <td style="text-align: center;">10</td>
 <td style="text-align: center;"></td>
 </tr>
 <tr>
 <td colspan="2" style="text-align: center;">Poids total des granulats = 500 g</td>
 <td colspan="2" style="text-align: center;"></td>
 </tr>
</table>


 <img alt="Figure1" src="/files/ftp_upload/16871/16871_Figure_PT_001.jpg">


Les courbes de granulométrie simplifient visuellement la distribution des tailles de particules et sont essentielles pour garantir que les granulats répondent aux spécifications de granulométrie requises pour les projets de construction.

Analyse par tamisage et courbes de granulométrie

L’analyse par tamis des agrégats est effectuée à l’aide d’un ensemble de tamis empilés par ordre décroissant de leur taille d’ouverture, de haut en bas.
Les tailles ...

Education

Enseignement

JoVE Core

Civil Engineering

Génie civil

Unit 1

Unité 1

Aggregates and Water

Granulats et eau

KEY TERMS AND CONCEPTS

TERMES ET CONCEPTS CLÉS

Sieve Analysis and Grading Curves

aggregate size testing with sieve grading

Aggregate size testing with sieve grading measures the particle size distribution of aggregate materials. It starts with a dried sample of aggregate that is weighed first. The sample is then sorted through a stack of square-opening sieves arranged from largest opening on top to smallest opening below.

The sieve stack is shaken or vibrated so the particles move through the openings by size. After a set time, the material left on each sieve is weighed. That weight is then written as a percentage of the total sample mass.

Next, the cumulative percentage passing each sieve is calculated to the nearest one percent. This value is found from the finest sieve and then moved upward through the stack. The data can be recorded for sieves such as ⅜ inch, No. 4, No. 8, No. 16, No. 30, No. 50, No. 100, and the bottom pan.

The grading curve is plotted on a graph using percentage passing on the vertical axis. The sieve aperture size is shown on the horizontal axis and uses a logarithmic scale. This curve gives a clear picture of particle size distribution and helps check whether aggregates meet grading requirements for construction projects.

Aggregate Size Testing with Sieve Grading

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sieve analysis and grading curves

Aggregate size testing with sieve grading measures the particle size distribution of aggregate materials. It starts with a dried sample of aggregate that is weighed first. The sample is then sorted through a stack of square-opening sieves arranged from largest opening on top to smallest opening below. The sieve stack is shaken or vibrated so the particles move through the openings by size. After a set time, the material left on each sieve is weighed. That weight is then written as a percentage...

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Water standards for concrete mixing help control strength and durability. Potable water is usually preferred. Even so, it should not contain too much sodium or potassium, because these salts can weaken concrete integrity. Water quality is judged by impurities such as dissolved solids, chlorides, and sulfates. The pH value is ideally between 6 and 8. Slightly acidic natural water may still be acceptable if it does not contain harmful organic matter or algae. Limits for these impurities depend...

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Aggregate types are grouped by size, petrographic characteristics, weight, and source. These categories help describe how different aggregates are identified and used in concrete. Size is one of the most common ways to classify them. Based on particle size, aggregates are either coarse or fine. Coarse aggregates are particles that do not pass through ASTM sieve No. 4. Fine aggregates are the particles that do pass through that sieve. Petrographic classification looks at shared mineral features.

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key terms and concepts

Learn how sieve grading measures aggregate particle size distribution, from weighing the sample to plotting cumulative percentage passing on a grading curve.

Aggregate Size Testing with Sieve Grading | JoVE K12

JoVE Core Civil Engineering provides a foundational exploration of essential construction materials in civil engineering, focusing on bricks, stones, steel, wood, and concrete through easy-to-understand animated videos. This collection covers the properties, manufacturing processes, and practical applications of these materials. Additionally, the accompanied science-in-action videos demonstrate the research experiments performed in laboratories.

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Aggregate Size Testing with Sieve Grading

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