ASTM Grout Cylinders: Tapered Cylinder Mold for Grout Volume Change
Introduction to Grout Cylinders and ASTM Standards
Grout cylinders are a crucial component in the construction industry, used to test the compressive strength of concrete and ensure its quality and durability. The American Society for Testing and Materials (ASTM) provides standards for testing and evaluating the properties of grout cylinders. ASTM C39 is the standard test method for compressive strength of cylindrical concrete specimens, while ASTM C31 specifies the requirements for making and curing concrete test specimens. Understanding these standards is essential for ensuring that grout cylinders are prepared, cured, and tested correctly. By adhering to these standards, construction professionals can ensure that their concrete meets the necessary performance criteria, leading to safer and more durable structures.
Cylinders, Tapered, for Grout Volume Change
Meets: ASTM C1090
What is Grout Volume Change Testing
Grout volume change testing is an important test to evaluate the performance of hydraulic-cement grout in various construction projects. The test method as per ASTM C1090 measures the change in height of cylindrical specimens from hydraulic-cement grout under controlled conditions. It is crucial that the cylinder diameter is proportional to the nominal maximum size of the coarse aggregate to achieve accurate testing and compliance for concrete strength evaluation. This test is necessary to check if the grout can maintain its volume and not shrink or expand which can affect the surrounding concrete. By following this standard construction professionals can ensure the grout used in their projects meets the performance criteria and hence the durability and safety of the structure. Drilled cores can also be used as cylindrical concrete specimens for testing compressive strength, following ASTM C42 guidelines.
Preparing Concrete Test Specimens
Preparing concrete test specimens is a critical step in ensuring the accuracy and reliability of test results. According to ASTM C31, concrete specimens must be molded and cured according to specific requirements. Cylinder molds can be made of metal or plastic, but must be non-absorbent, non-reactive to concrete, and maintain their shape and dimensions under all conditions of use. The molds must also be free from defects and have a smooth surface finish. Concrete specimens can be created by casting, molding, and curing fresh concrete in the field or by drilling cores from in-place concrete of an existing structure. Proper preparation of these specimens is essential to obtain valid and consistent test results, which are crucial for assessing the quality and performance of the concrete.
Curing Concrete Test Specimens
Curing concrete test specimens is a critical step in ensuring that they develop the desired strength and durability. According to ASTM C31, concrete specimens must be cured in a controlled environment with a consistent temperature and humidity level. The initial curing period typically lasts for 24 hours, during which the specimens must be stored in a temperature range of 60-80°F (15-27°C). The specimens must also be shielded from direct sunlight and radiating heating devices. After the initial curing period, the specimens can be stored in a moist room or water storage tank. Proper curing is essential to ensure that the concrete reaches its maximum load-bearing capacity and achieves the desired compressive strength.
Tapered Cylinder Molds Design
Tapered cylinder molds are designed for grout volume change testing as per ASTM C1090. These molds are made of metal or plastic and are tapered to facilitate easy removal of the cured grout specimen. Molds are non-absorbent and non-reactive to the grout to get accurate test results. The tapered shape allows for precise measurement of change in height which is critical for grout volume change characteristics. This design ensures the molds give reliable and consistent results making it a must have tool for any project involving hydraulic-cement grout.
How to do Grout Volume Change Test
Grout volume change test requires attention to detail and following ASTM C1090. The test involves preparing cylindrical specimens from hydraulic-cement grout and exposing them to controlled environment. The specimens are then measured for change in height over a period of 28 days. The test method involves the following steps:
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Preparation of grout specimens: Grout is mixed and poured into tapered cylinder molds and then vibrated to remove air bubbles.
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Initial curing: The specimens are cured in controlled environment for a specified period at a temperature of 23 ± 2.0°C (73 ± 3°F).
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Measurement: The specimens are measured for change in height at regular intervals of 1, 7, 14 and 28 days. During the compressive strength test, a compressive axial load is applied to the specimens until failure occurs, and the maximum load is recorded.
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Data analysis: The measured change in height is used to calculate the grout volume change.
By following these steps construction professionals can get accurate results and ensure the grout meets the standards for their projects.
Measuring Changes in Height of Cylindrical Concrete Specimens
Measuring changes in height of cylindrical concrete specimens is an important aspect of testing their compressive strength. According to ASTM C1090, the standard test method for measuring changes in height of hydraulic-cement grout, the test method covers measurement of changes in height of hydraulic-cement grout when cylinders are protected from evaporation, drying, moisture uptake, carbonation, and extreme temperatures. The test method involves measuring the initial height of the specimen and then measuring the change in height after a specified period of time. These measurements are crucial for determining the volume stability of the grout and ensuring that it meets the required performance standards.
What to do with the Test Results
Interpretation of test results from grout volume change test requires careful analysis of the data and its implications to the grout performance. The test results will give information on how the grout can maintain its volume and prevent shrinkage or expansion. The compressive strength is calculated by dividing the maximum load at failure by the cross-sectional area of the specimen. The data can be used to:
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Check if the grout is suitable for specific application: By knowing how the grout behaves under controlled condition professionals can determine if it’s good for their project.
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Compare different grout mixes or products: Test results will highlight the strengths and weaknesses of various grout formulations and help in selecting the best product for the job.
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Check if there’s an issue with the grout formulation or application: Any significant volume change means there’s an issue that needs to be addressed to ensure long term durability and structural integrity of the construction.
By following ASTM C1090 and interpreting the test results correctly engineers and construction professionals can ensure the grout used in their project meets the required standards and gives long term durability and structural integrity.
Supports initial curing concrete test specimens: ASTM C1090
Used to measure volume change of grout, the mold is made of steel tubing 0.25” wall x 3” dia. x 6”H (6 x 76 x 152mm). The mold supports ASTM standards for grout volume change test. The mold is split longitudinally with two quick-acting clamps welded to the mold. Top edge of mold is machine tapered to a narrow rim. Concrete specimens are critical in this application as they ensure accurate testing and compliance. Includes detachable base plate.
A Micrometer Bridge Set is useful tool for measuring grout volume change in various applications. It consists of micrometer, bridge supports and reference bar. During grouting the initial volume of grout is measured and the micrometer bridge set allows to measure at different time intervals. By measuring the change in grout volume you can monitor the grouting process and identify any potential issue such as shrinkage or expansion. This information is critical to ensure structural integrity and prevent damage. The Micrometer Bridge Set is a reliable and accurate way to measure grout volume change over time.
Accessories:
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Flow Cone Stand for flow cone positioning
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Grout Flow Cone for flowable grouts; requires HMA-146 or HMA-147 Orifice, sold separately
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Flow Cone w/ 0.75in Orifice for less flowable grouts
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2qt Stainless Steel Beaker for one test
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6qt Stainless Steel Beaker for up to three tests
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Large Display Stopwatch for flowability time
Best Practices for Handling and Storing Concrete Specimens
Handling and storing concrete specimens requires careful attention to detail to ensure that they are not damaged or contaminated. According to ASTM C31, concrete specimens must be handled and stored in a way that prevents damage from jarring or vibration. The specimens must also be protected from moisture loss by wrapping them in wet burlap or plastic. When transporting concrete specimens, they must be cushioned to prevent damage and kept in a controlled environment to prevent moisture loss. It is also important to label and identify each specimen clearly to ensure that they are properly tracked and recorded. Following these best practices helps maintain the integrity of the specimens and ensures accurate and reliable test results.