Coarse Aggregate Specific Gravity and Absorption Set

What is the Specific Gravity of Coarse Aggregate? Absorption Set

Coarse Aggregate Specific Gravity & Absorption Set

Need to weigh coarse aggregate samples while in water? This is the product for you. The Coarse Aggregate Specific Gravity & Absorption Set includes a Wire Basket with handle and 24qt polyethylene Water Container for accuracy and precision. Specific gravity is an important property of coarse aggregate.

The basket is No.8 stainless steel mesh and 8in dia. x 8in H (203x203mm) in size. There’s plenty of room to weigh different aggregate samples. Stainless steel construction means the basket can take a beating and the mesh will keep aggregate particles from escaping during washing or weighing. The handle on the basket is ergonomic for easy lifting so you can carry it between areas.

The Water Container is polyethylene and 24qt in size. This is the perfect size to hold water and suspend the aggregate samples during testing, making it an ideal choice for environmental sampling. It’s durable and lightweight so it’s easy to handle and move.

This product meets AASHTO T85 and ASTM C 127 test methods so it’s reliable and accurate. To calculate specific gravity, the aggregate sample is weighed in air and then weighed again while suspended in water. Whether in the lab or in the field the Coarse Aggregate Specific Gravity & Absorption Set is the tool for you if you need to test coarse aggregate samples for specific gravity and absorption. Understanding specific gravity helps in determining the material’s density.

In summary this product is well designed, durable and easy to use. From the stainless steel mesh basket to the polyethylene water container every part of the set is high quality and designed for accuracy and precision during testing. Whether you’re a pro or a DIYer, the Gilson SG-6 Coarse Aggregate Specific Gravity & Absorption Set is a must have for your testing needs. For those requiring precise particle size analysis, consider the Gilson 3in Wet Wash Sieves, All Stainless, 4in Deep, #140 for enhanced testing applications.

Coarse Aggregate

Coarse aggregate is a fundamental component in the construction industry, it plays a crucial role in determining the quality and durability of various structures. One of the essential properties of coarse aggregate is its specific gravity, which is defined as the ratio of the weight of a given volume of material to the weight of an equal volume of water at a specified temperature. This specific gravity of coarse aggregate is a critical parameter in mix design, as it affects the weight-to-volume relationships and the overall strength and durability of the concrete. Understanding the specific gravity helps in determining the material’s density and ensuring the right proportions in concrete mixtures, ultimately leading to more robust and long-lasting construction.

What is Specific Gravity of Coarse Aggregates

Specific gravity is a fundamental property of coarse aggregates that is critical in determining their quality and suitability for various construction applications. It is defined as the ratio of the weight of a given volume of material to the weight of an equal volume of water at a specified temperature. This property is important because it helps to understand the density and apparent relative density of the aggregate particles which directly affects the mix design and the overall strength and durability of the concrete. The concept of bulk SSD specific gravity is crucial in testing as it involves measuring the mass of aggregates under various conditions, including SSD (saturated surface-dry), to understand weight-to-volume relationships and assess aggregate durability.

To measure specific gravity of coarse aggregates, standard test methods such as ASTM C127 or AASHTO T 85 are used. These methods involve a step by step test procedure where the weight of a given volume of aggregate is compared to the weight of an equal volume of water. By dividing the weight of the aggregate by the weight of the water, the specific gravity is determined through standardized tests. This is important for engineers and construction professionals because it affects the material’s performance in various applications.

Higher specific gravity values for coarse aggregate means denser and stronger aggregate particles, means better quality.

Relative density is another term used to describe the relationship between the density values of various aggregates under different moisture conditions and specific gravity. This relationship is important for calculating the density values accurately.

The test method used for measuring specific gravity, such as ASTM C127 or AASHTO T 85, is critical for ensuring accurate and reliable results in construction and materials science.

Relationship with Other Properties

The specific gravity of coarse aggregate is related to other properties such as absorption, density and porosity. Absorption is the amount of water that can be absorbed by the aggregate, which is critical in determining the amount of asphalt binder required in asphalt mixtures. The density of coarse aggregate, which is the mass per unit volume of the material, is directly affected by its specific gravity. Porosity is the amount of voids or pores within the aggregate. These voids can affect both the specific gravity and absorption values, as highly porous aggregates tend to have lower specific gravities and higher absorption rates. Understanding these interrelated properties is important for optimizing mix designs and ensuring the durability and performance of construction materials.

Test Procedure to Determine Specific Gravity of Coarse Aggregates

The test procedure to determine specific gravity of coarse aggregates involves the following steps:

1. Sample Preparation: Get a representative sample of coarse aggregate. This coarse aggregate sample is then dried to a constant mass in an oven set at 100°C to 110°C. This step removes all moisture so you have a baseline to measure from. It is important to use oven-dried samples to ensure accurate specific gravity and absorption values.

2. Measurement of Sample Mass: Once dried, measure the mass of the sample using a balance or scale. This is critical because it’s the basis for the calculation of specific gravity. The mass is measured under three different conditions to obtain the three weights necessary for accurate calculations.

3. Measurement of Water Mass: Next, measure the mass of an equal amount of water. This step is for comparison purposes because specific gravity is the aggregate’s weight to the water’s weight. Remove any entrapped air from the aggregates by shaking the sample underwater or using mechanical agitation to ensure accurate measurements.

4. Calculation of Specific Gravity: Calculate the specific gravity by dividing the weight of the aggregate by the weight of the water. This gives you the bulk specific gravity which is important for aggregate density. Adequate soaking time is important to allow water to penetrate the pores of the aggregate particles, to ensure accurate specific gravity values.

5. Calculation of Apparent Specific Gravity: Bring the aggregate to a saturated surface dry (SSD) condition. Measure the weight of the SSD aggregate then compare it to the weight of an equal amount of water. This value accounts for the volume of aggregate particles minus the volume of aggregate pores filled with water. The test measures the weight of coarse aggregate under three different sample conditions to calculate various specific gravities and absorption.

By following these steps you can determine the specific gravity and apparent specific gravity of coarse aggregates and meet the requirements for construction projects.

Calculations and Formulas

The specific gravity of coarse aggregate can be calculated using the following formula: Specific Gravity = (Weight of material) / (Weight of equal volume of water). This formula is based on the principle that the weight of a given volume of material is equal to the weight of an equal volume of water. Additionally, the specific gravity of coarse aggregate can be calculated using the equation: Specific Gravity = (Mass of oven-dry sample + Mass of SSD sample - Mass of immersed sample) / (Mass of oven-dry sample). This equation takes into account different sample conditions, including oven-dry, saturated surface dry (SSD), and immersed. By understanding and applying these formulas, professionals can accurately determine the specific gravity of coarse aggregates, ensuring the right mix proportions and enhancing the quality of construction projects.

Best Practices for Coarse Aggregate Testing

To get accurate and reliable results in coarse aggregate testing follow best practices. Here are some tips:

1. Get a Representative Sample: Always get and prepare a representative sample of coarse aggregate for testing. This will ensure the test results are reflective of the entire material. Aggregate durability is assessed by measuring absorption, which indicates the likelihood of the aggregate to absorb asphalt binder and its overall durability.

2. Follow Standard Test Methods: Follow standard test methods such as ASTM C127 or AASHTO T 85. These methods will give you consistent and reliable results so the specific gravity values are accurate.

3. Calibrated Equipment: Make sure all equipment including balances and scales are calibrated. Accurate measurements are critical for specific gravity and absorption of coarse aggregates. Highly absorptive aggregates are undesirable in Hot Mix Asphalt (HMA) because they absorb significant amounts of asphalt binder, leading to higher material costs.

4. Temperature Control: Test at a controlled temperature to avoid variations in results. Temperature variations will affect the measurements and give you inaccurate specific gravity values. Aggregate plays a big role in testing procedures especially in weight-to-volume relationships and absorption rates.

5. No Air Traps: During testing avoid air traps in the aggregate samples. Air traps will give you wrong measurements and affect the test results. Voids filled by asphalt (VFA) is critical in assessing aggregate performance and its capacity to absorb asphalt binder.

By following these best practices engineers and construction professionals can ensure the coarse aggregate meets the requirements and has the properties needed for a specific project. Accurate testing is key to getting the desired performance and durability in concrete structures.