Balloon Density Apparatus, 1/20 cu. ft.

Balloon Density Apparatus, 1/20 cu. ft.

The Balloon Density Apparatus is an essential tool for geotechnical engineers and technicians, providing a straightforward method for determining the in-place density of compacted soils in earth fills and embankments. This device offers a practical and accurate field alternative to other density testing methods.

How it Works

The operating principle is simple yet effective. The apparatus consists of a calibrated, water-filled cylinder equipped with a hand pump. A thin, durable rubber membrane (balloon) at the base is designed to expand under pressure and perfectly conform to the shape of a test hole.

The testing process involves these key steps:

1. Prepare the Test Hole: A flat base plate is placed on the prepared soil surface to serve as a stable template. A hole is carefully excavated within the template's opening. All soil removed from the hole is meticulously collected and weighed.
2. Measure the Volume: The balloon density tester is positioned over the empty hole. The operator uses the hand pump to pressurize the cylinder, forcing the water to displace the balloon and completely fill the void.
3. Read the Displacement: The volume of the test hole is directly read from the double-graduated scale on the high-strength, transparent plastic cylinder. The graduations are marked in increments of .00025 cubic feet or 7 cubic centimeters, allowing for precise measurement.
4. Calculate Density: The in-place density of the soil is calculated by dividing the weight of the excavated soil by the measured volume of the hole. A sample of the excavated soil is also retained to determine its moisture content, allowing for calculation of the dry density.

This method is ideal for most compacted soils but is not recommended for very soft soils that may deform during the test or for soils where the hole cannot maintain a stable volume.

Choosing the Right Model

Selecting the correct model depends on the maximum particle size of the soil being tested:

• 1/20 cu. ft. Model (This Model): Suitable for soils with a maximum particle size of 1/2in (13mm).
• 1/13 cu. ft. Model: Designed for soils with a larger particle size, up to 1in (25mm).

Each unit is a complete field kit, arriving with all the necessary components for immediate use.

Features:

• Accurate & Direct Measurement: Provides a reliable method for determining in-place density.
• Durable Construction: Features a high-strength, transparent plastic cylinder for clear visibility of the double-graduated scale.
• Complete Kit: Comes with all accessories needed to perform density tests right out of the box.
• Pressure Control: An integral pressure gauge ensures consistent and repeatable results by allowing precise control during calibration and testing.

Included Items:

• 1/20 cu. ft. Balloon Density Tester
• Double-Graduated Cylinder
• Aluminum Base Plate
• Pressure/Vacuum Pump Assembly with Quick-Coupler
• Integral Pressure Gauge
• Ten (10) Balloons

Accessories:

• Extra Balloons are available in packs of ten to ensure you are always prepared for testing.

Meets Test Methods:

• ASTM D2167