ASTM C880 is a standard test method for determining the flexural strength of stone using a simple beam with quarter-point loading. The method indicates differences in flexural strength between dimension stones, and it gives one element for comparing stones of the same type.
The scope of ASTM C880 includes-
- Material type: Dimension stone, cut into rectangular beam specimens.
- Purpose: Indicating differences in flexural strength between dimension stones and comparing stones of the same type.
- Properties evaluated: Flexural strength, tested with the load perpendicular and parallel to the bedding plane and under wet conditions when required.
- Testing method: A stone beam rests on two lower supports, and a testing machine loads it through two upper bearing blocks at the quarter points until the specimen fails. The lower support span is 318 mm (12.5 in.), and the upper loading span is 159 mm (6.25 in.).
- Results: Flexural strength in megapascals (MPa) or pounds per square inch (psi), averaged for each test condition.
- Test limitations: Natural variation between specimens affects individual results, so the method calls for several specimens per condition. When a job thickness other than 32 mm (1.25 in.) applies, results describe the stone at that job thickness.
- Test conditions: Technicians test at least five specimens for each test condition, conditioned either dry (48 hours at 140 ± 4°F) or wet (48 hours in water at room temperature).
- Applications: Material selection, product comparison, and quality control of dimension stone for paving, cladding, and other spanning uses.
What are the Uses of ASTM C880 Testing?
ASTM C880 gives stone suppliers and designers a common way to measure how much bending load a dimension stone carries before it breaks. Engineers use the results to compare stones and to judge whether a stone suits a spanning or load-bearing application. This test method-
- Determines the flexural strength of dimension stone with a simple beam under quarter-point loading.
- Shows differences in flexural strength between dimension stones.
- Compares stones of the same type.
- Tests specimens with the load perpendicular and parallel to the bedding plane.
- Tests specimens under dry and wet conditions.
- Serves as the flexural test cited in the physical requirements of ASTM Committee C18 dimension stone specifications.
- Supports material selection and supplier quality checks.
Which Materials Can Be Tested Under ASTM C880?
ASTM C880 applies to dimension stone, such as granite, marble, limestone, and sandstone, cut into rectangular beams. Technicians saw and finish-grind each specimen to the required size, then condition it dry or wet according to the test condition. Suppliers and designers commonly select this stone method for paving, wall cladding, and other places where the stone spans gaps or carries uneven loads.
Why is ASTM C880 Important?
Dimension stone in paving, cladding, and foundations often spans gaps, rests on limited supports, or carries uneven loads, and these conditions bend the stone. A stone with low flexural strength can crack under that bending. ASTM C880 measures this bending resistance in a standard way, so suppliers and designers compare stones on the same basis. The results show how one stone differs from another and how stones of the same type compare.
