ASTM C99/C99M – Modulus of Rupture of Dimension Stone

← Back to all standards

ASTM C99 is the test method for the modulus of rupture (flexural strength in bending) of dimension stone. To match this to your program, talk with our team.

What ASTM C99 Covers

It compares the bending performance of stone types and supports material qualification for dimension stone used in construction and cladding.

How the Test Is Run

A stone specimen is supported and loaded in bending until it breaks, and the modulus of rupture is calculated from the failure load and specimen dimensions.

Why It Matters

Flexural strength governs how dimension stone resists bending in service; a flexure fixture and accurate load measurement are essential.

Reading the Designation

Cited as ASTM C99 with its edition year. Confirm the edition and specimen or fixture requirements before finalizing setup. To configure a testing setup, request a quote.

Related Standards

EN 491 covers concrete roofing tiles, another construction product tested in bending.

Request a Quote

Setting up dimension stone flexural testing to ASTM C99? Request a quote and our team will help you build a system matched to your stone type and specimen size.


TensileMill CNC products for ASTM C99

Our specimen-preparation systems and testing equipment compatible with ASTM C99:


Build your ASTM C99 workflow with TensileMill CNC

From specimen preparation to the test itself, TensileMill CNC supports the full ASTM C99 testing chain. That typically means high-capacity frames and fixtures for compression and flexural testing. Share your material mix and throughput, and we will recommend a setup that fits ASTM C99.