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

표준 체 세트를 통해 체질되는 미세한 응집체의 샘플을 고려하십시오. 각 체에 유지되는 골재의 무게를 기록하십시오.
각 체에 유지되는 응집체의 누적 중량을 계산하고 이를 총 시료 중량의 백분율로 표시합니다.
예를 들어, 모든 입자가 특정 체 위 또는 그 위에 유지되고 아무 것도 통과하지 못하는 경우, 해당 체와 그 아래에 쌓인 체에 대해 유지되는 누적 백분율은 100으로 입력됩니다.
섬도 계수는 각 체에 유지된 누적 백분율을 합산하고 총계를 100으로 나누어 계산합니다.
fineness modulus는 골재의 등급을 나타내는 숫자 지수입니다.
동일한 공급원의 응집체를 사용하는 경우, 미세 응집체의 그라데이션에서 약간의 변화는 굵은 응집체보다 시각적으로 덜 분명합니다.
이러한 차이는 fineness modulus 값에 반영되며, 이는 거친 응집체보다 미세한 골재에 더 통찰력이 있습니다.
일반적으로 미세 골재에 대한 섬도 계수 값의 범위는 2.3에서 3.1 사이이며, 값이 높을수록 골재가 더 거칠어집니다.

조립률

골재의 조립률(FM)은 입자의 거칠기 또는 미세함을 측정하는 수치 지수입니다. 지정된 일련의 체에 남아 있는 골재의 누적 백분율을 더하고 그 합계를 100으로 나누어 계산합니다.
ASTM 체 세트를 통하여 모래의 체 분석을 수행한다고 생각해 봅시다. 바닥에 놓인 각 체와 팬에 남아 있는 골재의 무게는 표 1의 열 B에 나와 있는 대로 기록됩니다.
모래의 조립률을 구하려면 각 체에 남아 있는 골재의 누적 무게(표1의 C열)를 계산하고 총 무게의 백분율로 표현합니다(표1의 D열). 마지막으로 각 체의 누적 잔류무게의 백분율의 합을 구한 후, 그 값에 100을 곱하여 모래의 조립률을 계산합니다.

표 1: 모래에 대한 체 분석

<table style="margin: 0 auto;">
	<tbody style="border: 1px solid black;">
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">A열</td>
			<td style="color: black; border: 1px solid black; text-align: center;">B열</td>
			<td style="color: black; border: 1px solid black; text-align: center;">C열</td>
			<td style="color: black; border: 1px solid black; text-align: center;">D열</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">ASTM 체</td>
			<td style="color: black; border: 1px solid black; text-align: center;">각 체의 잔류무게(g)</td>
			<td style="color: black; border: 1px solid black; text-align: center;">각 체의 누적 잔류무게(g)</td>
			<td style="color: black; border: 1px solid black; text-align: center;">각 체의 누적 잔류무게 백분율(%)</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">⅜cm</td>
			<td style="color: black; border: 1px solid black; text-align: center;">0</td>
			<td style="color: black; border: 1px solid black; text-align: center;">0</td>
			<td style="color: black; border: 1px solid black; text-align: center;">0</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">4호</td>
			<td style="color: black; border: 1px solid black; text-align: center;">5</td>
			<td style="color: black; border: 1px solid black; text-align: center;">0+5 = 5</td>
			<td style="color: black; border: 1px solid black; text-align: center;">5/500 = 1</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">8호</td>
			<td style="color: black; border: 1px solid black; text-align: center;">55</td>
			<td style="color: black; border: 1px solid black; text-align: center;">5+55 = 60</td>
			<td style="color: black; border: 1px solid black; text-align: center;">60/500 = 12</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">16호</td>
			<td style="color: black; border: 1px solid black; text-align: center;">65</td>
			<td style="color: black; border: 1px solid black; text-align: center;">60+65 = 125</td>
			<td style="color: black; border: 1px solid black; text-align: center;">125/500 = 25</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">30호</td>
			<td style="color: black; border: 1px solid black; text-align: center;">90</td>
			<td style="color: black; border: 1px solid black; text-align: center;">125+90 = 215</td>
			<td style="color: black; border: 1px solid black; text-align: center;">215/500 = 43</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">50호</td>
			<td style="color: black; border: 1px solid black; text-align: center;">160</td>
			<td style="color: black; border: 1px solid black; text-align: center;">215+160 = 375</td>
			<td style="color: black; border: 1px solid black; text-align: center;">375/500 = 75</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">100호</td>
			<td style="color: black; border: 1px solid black; text-align: center;">90</td>
			<td style="color: black; border: 1px solid black; text-align: center;">375+90 = 465</td>
			<td style="color: black; border: 1px solid black; text-align: center;">465/500 = 93</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">바닥 팬</td>
			<td style="color: black; border: 1px solid black; text-align: center;">35</td>
			<td style="color: black; border: 1px solid black; text-align: center;">총 무게 = 465+35 = 500</td>
			<td style="color: black; border: 1px solid black; 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;">

일반적으로 모래의 조립률은 약 2.3~3.1입니다. 값이 낮을수록 모래가 미세하고, 값이 높을수록 거칠다는 것을 의미합니다.

표준 체 세트를 통해 체질되는 미세한 응집체의 샘플을 고려하십시오. 각 체에 유지되는 골재의 무게를 기록하십시오.
계산 ...

Education

교육

JoVE Core

Civil Engineering

토목공학

Unit 1

제1단원

Aggregates and Water

골재 및 용수

KEY TERMS AND CONCEPTS

주요 용어 및 개념

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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How Aggregate Size Affects Concrete Mix

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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 offers a foundational exploration of essential construction materials such as bricks, stones, steel, wood, and concrete, along with fluid mechanics topics like flow over immersed bodies, open channel flow, and dimensional modeling. It also covers key surveying concepts, including leveling, traverse adjustments, curve design, topographic mapping, and geospatial technologies (GPS & GIS). Science-in-action videos showcase laboratory research on materials, fluids, and surveying practices in real-world engineering systems.

civil engineering

Fineness Modulus from Sieve Analysis

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