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

Standart bir elek setinden elenen ince agregaların bir örneğini düşünün. Her elek üzerinde tutulan agregaların ağırlığına dikkat edin.
Her bir elek üzerinde tutulan agregaların kümülatif ağırlığını hesaplayın ve bunu toplam numune ağırlığının yüzdesi olarak ifade edin.
Örneğin, tüm parçacıklar belirli bir elek üzerinde veya üzerinde tutuluyorsa ve içinden hiçbir şey geçmiyorsa, o elek ve altında istiflenenler için tutulan kümülatif yüzde 100 olarak girilir.
İncelik modülü, her bir elek üzerinde tutulan kümülatif yüzdenin toplanması ve toplamın 100'e bölünmesiyle hesaplanır.
İncelik modülü, agregaların derecelendirilmesini temsil eden sayısal bir indekstir.
Aynı kaynaktan alınan agregalar kullanıldığında, ince agregaların derecelendirilmesindeki küçük değişiklikler, kaba agregalara göre görsel olarak daha az belirgindir.
Bu farklılıklar, ince agregalar için kaba agregalardan daha anlayışlı olacak olan incelik modülü değerine yansıtılacaktır.
Tipik olarak, ince agregalar için incelik modülünün değeri 2.3 ila 3.1 arasında değişir; değer ne kadar yüksekse, agregalar o kadar kaba olur.

İncelik modülü

Agrega incelik modülü (FM), parçacıkların iriliğini veya inceliğini ölçen sayısal bir endekstir. Belirli bir elek dizisinin her birinde tutulan agregaların kümülatif yüzdelerinin toplanıp 100'e bölünmesiyle hesaplanır.

ASTM eleklerinden oluşan bir set ile kuma elek analizi yapmayı düşünün. Her elekte ve eleğin altına yerleştirilmiş tavada tutulan agrega ağırlığı, Tablo 1'in B Sütununda verildiği gibi kaydedilir.

Kumun incelik modülünü belirlemek için, her elekte tutulan agreganın kümülatif ağırlığını hesaplayın (Tablo 1'in C Sütunu) ve bunu toplam ağırlığın yüzdesi olarak ifade edin (Tablo 1'in D Sütunu). Son olarak, her elekte tutulan agreganın kümülatif yüzdelerinin toplamı belirleyin ve kumun incelik modülünü elde etmek için 100 ile çarpın.

Tablo 1: Kum üzerinde elek analizi

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Sütun A</td>
			<td>Sütun B</td>
			<td>Sütun C</td>
			<td>Sütun D</td>
		</tr>
		<tr>
			<td>ASTM Eleği</td>
			<td>Her elekte tutulan ağırlık (g)</td>
			<td>Her elekte tutulan kümülatif ağırlık (g)</td>
			<td>Her elekte tutulan kümülatif yüzde (%)</td>
		</tr>
		<tr>
			<td>
			⅜ cm
			</td>
			<td>0</td>
			<td>0</td>
			<td>0</td>
		</tr>
		<tr>
			<td>Hayır. 4</td>
			<td>5</td>
			<td>0+5 = 5</td>
			<td>5/500 = 1</td>
		</tr>
		<tr>
			<td>Hayır. 8</td>
			<td>55</td>
			<td>5+55 = 60</td>
			<td>60/500 = 12</td>
		</tr>
		<tr>
			<td>Hayır. 16</td>
			<td>65</td>
			<td>60+65 = 125</td>
			<td>125/500 = 25</td>
		</tr>
		<tr>
			<td>Hayır. 30</td>
			<td>90</td>
			<td>125+90 = 215</td>
			<td>215/500 = 43</td>
		</tr>
		<tr>
			<td>Hayır. 50</td>
			<td>160</td>
			<td>215+160 = 375</td>
			<td>375/500 = 75</td>
		</tr>
		<tr>
			<td>Hayır. 100</td>
			<td>90</td>
			<td>375+90 = 465</td>
			<td>465/500 = 93</td>
		</tr>
		<tr>
			<td>Alt tava</td>
			<td>35</td>
			<td>Toplam ağırlık = 465+35 = 500</td>
			<td></td>
		</tr>
	</tbody>
</table>
<img alt="Eq1" src="/files/ftp_upload/16872/16872%20_Equation_PT_001v2.svg" style="height: 14px;">
<img alt="Eq2" src="/files/ftp_upload/16872/16872%20_Equation_PT_002v2.svg" style="height: 36px;">
Genel olarak kumun incelik modülü 2,3 ila 3,1 arasındadır. Daha düşük değerler daha ince kumu gösterirken, daha yüksek değerler kumun daha iri taneli olduğu anlamına gelir.

İncelik Modülü

Standart bir elek setinden elenen ince agregaların bir örneğini düşünün. Her elek üzerinde tutulan agregaların ağırlığına dikkat edin.
Hesaplayın ...

Education

JoVE Core

Civil Engineering

İnşaat Mühendisliği

Unit 1

Ünite 1

Aggregates and Water

Agregalar ve Su

KEY TERMS AND CONCEPTS

TEMEL TERİMLER VE KAVRAMLAR

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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key terms and concepts

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.

civil engineering

Fineness Modulus from Sieve Analysis

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