Name: fineness modulus from sieve analysis
Uploaded: 2024-11-07T14:48:25.000Z
Duration: 1 min 19 s
Channel: JoVE

Considere una muestra de agregados finos que se tamizan a través de un conjunto estándar de tamices. Tenga en cuenta el peso de los agregados retenidos en cada tamiz.
Calcule el peso acumulado de los agregados retenidos en cada tamiz y expréselo como un porcentaje del peso total de la muestra.
Si, por ejemplo, todas las partículas se retienen sobre o por encima de un tamiz en particular, y nada pasa a través de él, el porcentaje acumulado retenido para ese tamiz y los apilados debajo de él se ingresa como 100.
El módulo de finura se calcula sumando el porcentaje acumulado retenido en cada tamiz y dividiendo el total por 100.
El módulo de finura es un índice numérico que representa la clasificación de los agregados.
Cuando se utilizan agregados de la misma fuente, las ligeras variaciones en la gradación de los agregados finos son menos obvias visualmente que con los agregados gruesos.
Estas diferencias se reflejarán en el valor del módulo de finura, que será más perspicaz para los agregados finos que para los agregados gruesos.
Típicamente, el valor del módulo de finura para agregados finos oscila entre 2.3 y 3.1; cuanto mayor es el valor, más gruesos son los agregados.

módulo de finura

El módulo de finura (FM) de los áridos es un índice numérico que mide la tosquedad o finura de las partículas. Se calcula sumando los porcentajes acumulados de áridos retenidos en cada una de una serie específica de tamices y dividiendo la suma por 100.

Considere realizar un análisis de tamiz en la arena a través de un conjunto de tamices ASTM. Se registra el peso del agregado retenido en cada tamiz y la bandeja colocada en el fondo, como se indica en la Columna B de la Tabla 1. Para determinar el módulo de finura de la arena, se calcula el peso acumulado de agregado retenido en cada tamiz (columna C de la Tabla 1) y se expresa como porcentaje del peso total (columna D de la Tabla 1). Finalmente, se determina la suma de los porcentajes acumulados de agregado retenido en cada tamiz y se multiplica por 100 para obtener el módulo de finura de la arena.

Tabla 1: Análisis granulométrico de la arena

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td style="text-align: center;">Columna A</td>
			<td style="text-align: center;">Columna B</td>
			<td style="text-align: center;">Columna C</td>
			<td style="text-align: center;">Columna D</td>
		</tr>
		<tr>
			<td style="text-align: center;">Tamiz ASTM</td>
			<td style="text-align: center;">Peso retenido en cada tamiz (g)</td>
			<td style="text-align: center;">Peso acumulado retenido en cada tamiz (g)</td>
			<td style="text-align: center;">Porcentaje acumulado retenido en cada tamiz (%)</td>
		</tr>
		<tr>
			<td style="text-align: center;">⅜ de centímetros</td>
			<td style="text-align: center;">0</td>
			<td style="text-align: center;">0</td>
			<td style="text-align: center;">0</td>
		</tr>
		<tr>
			<td style="text-align: center;">No. 4</td>
			<td style="text-align: center;">5</td>
			<td style="text-align: center;">0+5 = 5</td>
			<td style="text-align: center;">5/500 = 1</td>
		</tr>
		<tr>
			<td style="text-align: center;">No. 8</td>
			<td style="text-align: center;">55</td>
			<td style="text-align: center;">5+55 = 60</td>
			<td style="text-align: center;">60/500 = 12</td>
		</tr>
		<tr>
			<td style="text-align: center;">No. 16</td>
			<td style="text-align: center;">65</td>
			<td style="text-align: center;">60+65 = 125</td>
			<td style="text-align: center;">125/500 = 25</td>
		</tr>
		<tr>
			<td style="text-align: center;">No. 30</td>
			<td style="text-align: center;">90</td>
			<td style="text-align: center;">125+90 = 215</td>
			<td style="text-align: center;">215/500 = 43</td>
		</tr>
		<tr>
			<td style="text-align: center;">No. 50</td>
			<td style="text-align: center;">160</td>
			<td style="text-align: center;">215+160 = 375</td>
			<td style="text-align: center;">375/500 = 75</td>
		</tr>
		<tr>
			<td style="text-align: center;">No. 100</td>
			<td style="text-align: center;">90</td>
			<td style="text-align: center;">375+90 = 465</td>
			<td style="text-align: center;">465/500 = 93</td>
		</tr>
		<tr>
			<td style="text-align: center;">Sartén inferior</td>
			<td style="text-align: center;">35</td>
			<td style="text-align: center;">Peso total = 465+35 = 500</td>
			<td style="text-align: center;"></td>
		</tr>
	</tbody>
</table>

<img alt="Equation1" src="/files/ftp_upload/16872/16872%20_Equation_PT_001v2.svg" style="height: 14px;">

<img alt="Equation2" src="/files/ftp_upload/16872/16872%20_Equation_PT_002v2.svg" style="height: 36px;">

En general, la arena tiene un módulo de finura de alrededor de 2,3 a 3,1. Los valores más bajos indican arena más fina, mientras que los valores más altos significan que la arena es más gruesa.

Módulo de finura

Considere una muestra de agregados finos que se tamizan a través de un conjunto estándar de tamices. Tenga en cuenta el peso de los agregados retenidos en cada tamiz.
Calcule el ...

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Fineness Modulus

fineness modulus from sieve analysis

Fineness modulus is a numerical index used to describe how coarse or fine aggregate particles are. For sand, it is found from sieve analysis using a standard set of ASTM sieves. The result helps show whether the sample is finer or more coarse.

To calculate fineness modulus, first record the weight of aggregate retained on each sieve and in the pan at the bottom. Then find the cumulative weight retained on each sieve. Next, express each cumulative weight as a percentage of the total sample weight. The fineness modulus is obtained by adding those cumulative percentages and dividing the sum by 100.

A sand sample can be tested with sieves such as ⅜ inch, No. 4, No. 8, No. 16, No. 30, No. 50, and No. 100. In the example, the retained weights are 0 g, 5 g, 55 g, 65 g, 90 g, 160 g, 90 g, and 35 g in the bottom pan. The cumulative percentages retained are 0, 1, 12, 25, 43, 75, and 93, based on a total weight of 500 g.

In general, sand has a fineness modulus of about 2.3 to 3.1. Lower values mean the sand is finer. Higher values mean the sand is more coarse.

Fineness Modulus from Sieve Analysis

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fineness modulus

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Learn how fineness modulus is calculated from sieve analysis of sand, using cumulative retained percentages on ASTM sieves to judge particle size.

Fineness Modulus from Sieve Analysis | 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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Fineness Modulus from Sieve Analysis

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