experiment (1) total moisture content...
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Materials Laboratory
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Experiment (1)
Total Moisture Content
Objective:
Determine the total moisture content of aggregate ( fine or coarse).
ايجاد الوحتوى الوائي للركام )الاعن أو الخشي(.
Definition:
Total Moisture Content:
- Is the water present in the aggregate either inside the pores or at the surface.
- The total weight of water present, expressed as a percentage of the oven-dry
weight.
Aggregate Moisture:
Absorbed water : water present in the pores of porous aggregate particles.
Surface water : water present on the surface of aggregate particles (also called
free water).
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Moisture States of Aggregates:
Oven-dry (OD): All moisture is removed from the aggregate by heating in
an oven at 105°c to constant weight "all pores are empty".
رطوبة علي السطح وال داخل الفراغات. ال يوجذ
Air-Dry(AD): All the moisture is removed from the surface, but internal
pores are partially full.
رطوبة علي السطح، هع اهكاية وجود هاء داخل الفراغات. ال يوجذ
Saturated–Surface–dry (SSD): All pores are filled with water, but there is
no film of water on the surface.
في حالة هشبعة. رطوبة علي السطح، هع وجود هاء داخل الفراغات يوجذ ال
Wet: All pores are completely filled with water with a film of water on the
surface.
الفراغات الذاخلية هشبعة هع اهكاية وجود هاء "رطوبة" علي السطح.
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Apparatus:
• A balance
• Drying Oven
• Sample Container
Procedures:
Max. Aggregate Size عهى تى اختيار حجى انعية باءي 1-
Mass of aggregate sampleو max. aggregate size نجدول انتاني يوضح انعالقة بي ا
Max. Aggregate Size (mm) Minimum Mass of aggregate
sample (Kg)
4.75 0.5
9.5 1.5
12.5 2
19 3
25 4
37.5 6
50 8
63 10
(.WWقوو بوز انعية "انوز انرطب") -2
ضع انعية في انفر "جفف انعية". -3
(.Wdخرج انعية ي انفر وس انعية "انوز انجاف") -4
Calculations
Moisture Content :
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Experiment (2)
Specific Gravity and Absorption of Aggregates
)اناعى وانخش(وااليتصاص نهركاو ةانوعي نكثافةا
Definition:
1- Specific Gravity: Is the ratio of the weight of a unit volume of aggregate to
the weight of an equal volume of water.
السبة بيي وزى حجن هعيي هي الحصي الي وزى فس الحجن هي الواء.
NOTE:
Specific gravity depends on the volume you assume for the aggregate particles.
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Bulk Specific Gravity (dry): Is the ratio of the dry weight of a unit volume of
aggregate to the weight of an equal volume of water.
السبة بيي وزى حجن هعيي هي الركام "الوزى الجاف" الي وزى فس الحجن هي الواء.
Bulk Specific Gravity (SSD): Is the ratio of the weight of a unit volume of
aggregate (SSD) "includes the weight of water in pores" to the weight of an equal
volume of water.
السبة بيي وزى حجن هعيي هي الركام "الحالة الوشبعة" الي وزى فس الحجن هي الواء.
Apparent Specific Gravity:
Bulk Specific Gravity (dry):
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Bulk Specific Gravity (SSD):
2- Absorption: Is the weight of water present only inside the pores of
aggregate, expressed as a percentage of the dry weight.
NOTE: Absorption represents the maximum amount of water the aggregate can
absorb. Absorption can calculated from the difference in weight between the SSD
and OD states, expressed as a percentage of the OD weight.
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A. Coarse Aggregate
Procedures:
Calculations:
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B. Fine Aggregate
Procedures:
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Calculations:
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Experiment (3)
Sieve Analysis of Fine & Coarse Aggregates
خهي نهركاو اناعى وانخشاختبار انتحهيم ان
Definitions:
Sieve Analysis: is a procedure to separate fine material from course material by
means of a series of woven or perforated surfaces. The proportion of different size
particles is recorded. This record is the conclusion of the analysis.
Figure 1: Sieves
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Coarse aggregate sieves:
Fine aggregate sieves:
Bold = Full sieves
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Fineness modulus : an index of the coarseness or fineness of an aggregate; it is
computed as the sum of the fraction retained on each full series sieve starting
from the No. 100 sieve.
In general a small value indicated a fine material while a large value indicates a
coarse material. The value for fine aggregates commonly ranges from 2.3 to 3.1
and for coarse aggregate from 6.50 to 8.00.
Type of gradation:
Poorly-graded (A) Well-graded (B) Gap graded (C)
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Objective:
Determine the particle size distribution of fine and coarse aggregates by sieving.
Apparatus:
A balance.
Drying Oven.
Mechanical shaker.
Set of sieves.
Procedures:
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Calculations
Calculate %Cumulative retained weight & %passing as follow:
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Draw the relationship between sieve size (opening) & percentage of passing, and then get the required information from the curves.
Calculate the Fineness Modulus of fine aggregate .