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Analytical approaches paired with common oscillatory shear tests can describe not only solid-like and fluid-like behavior of granular hydrogels but also transient characteristics inherent in yielding and unyielding processes. Combining oscillatory shear testing with consideration of Brittility (Bt) via the Kamani-Donley-Rogers (KDR) model, we show granular hydrogels behave as brittle yield stress fluids with complex transient rheology. We quantify steady and transient rheology as a function of microgel (composition; diameter) and granular (packing; droplet heterogeneity) assembly properties for mixtures of polyethylene glycol and gelatin microgels. The KDR model with Bt captures granular hydrogel behavior for a wide range of design parameters, reducing the complex transient rheology to a determination of model parameters. We describe the impact of composition on rheological behavior and model parameters in monolithic and mixed granular hydrogels. The model robustly captures self-healing behavior and reveals granular relaxation time depends on strain amplitude. This quantitative framework is an important step toward rational design of granular hydrogels for applications ranging from injection and\n                  <jats:italic>in situ<\/jats:italic>\n                  stabilization to 3D bioprinting.\n                <\/jats:p>","DOI":"10.1101\/2025.02.22.639638","type":"posted-content","created":{"date-parts":[[2025,2,27]],"date-time":"2025-02-27T23:10:18Z","timestamp":1740697818000},"source":"Crossref","is-referenced-by-count":3,"title":["Granular hydrogels as brittle yield stress fluids"],"prefix":"10.64898","author":[{"given":"G.B.","family":"Thompson","sequence":"first","affiliation":[{"name":"Dept. Chemical and Biomolecular Engineering University of Illinois Urbana-Champaign Urbana, IL 61801"},{"name":"Carl R. 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