|Statement||by Torben C. Hansen.|
|Series||Svenska Forkningsinstitutet Fo r Cement Och Betong Vid Kungl Tekniska Ho gskolan 1 Stockholm -- Handlingar Nr 31|
|Contributions||Svenska Forsningsinstitutet fo r Cement Och Betong.|
|The Physical Object|
|Number of Pages||112|
solid molecules explains the basic nonlinear effects in low-stress creep, such as the drying creep effect. Further nonlinear behavior, due mainly to gradual microcracking, appears in high-stress creep. The solution of the creep and shrinkage of a concrete body depends on the solution of the. Stress relaxation describes how polymers relieve stress under constant strain. Because they are viscoelastic, polymers behave in a nonlinear, non-Hookean fashion. This nonlinearity is described by both stress relaxation and a phenomenon known as creep, which describes how . stress-strain curve is concave up as observed in ligament. We also show that it is inconsistent to assume a Fung-type constitutive law (Fung, ) for both creep and relaxation. Using published data of Thornton, et al., () the nonlinear interrelation developed herein predicts creep behavior from relaxation data well (R ≥ ). Aging of concrete has a quite substantial effect on the degree of stress relaxation; e.g., it differs by a factor of 2–3 for concrete at an age of 3 and days. The effect of aging of concrete on the stress relaxation coefficient must be taken into account to to an age of at least days.
Preface --SP Managing Deflection, Shortening and Crack Arising from Restrained Contraction / S.J. Alexander AS Creep and Shrinkage Models for Normal and High Strength Concrete / R. I. Gilbert Sensitivity of the Models for Predicting Shrinkage of Concrete / A. Al-Manaseer and S. Ristanovic Deviations from the. Modeling of Creep for Structural Analysis Book Summary: This book develops methods to simulate and analyze the time-dependent changes of stress and strain states in engineering structures up to the critical stage of creep rupture. The objective of this book is to review some of the classical and recently proposed approaches to the modeling of creep for structural analysis applications. In the case of stress relaxation, the shear strain is constant and it corresponds to the initially ap- J. Murali Krishnan, K.R. Rajagopal / Mechanics of Materials 36 () – Creep/Relaxation, Cracking, and Material Properties Polymer viscoelasticity and the relaxation modulus 10 Hours of Relaxing Music - Sleep Music, Piano Music for Stress Relief.
A tensile test until breakage and a creep and relaxation test on a polypropylene fibre are carried out and the resulting creep and stress relaxation curves are fit by a model adopting a fraction-exponential kernel in the viscoelastic operator. The models using fraction-exponential functions are simpler than the complex ones obtained from combination of dashpots and springs and, furthermore Cited by: 3. The relaxation modulus used for stress prediction was obtained from the creep data fitted using a log-power creep function. These findings show that tensile creep and stress relaxation are important properties of Portland cement concrete. These properties however are reduced in concretes containing blended cements. For example, moderate creep in concrete is sometimes welcomed because it relieves tensile stresses that might otherwise lead to cracking. Unlike brittle fracture, creep deformation does not occur suddenly upon the application of stress. Instead, strain accumulates as a result of long-term stress. Therefore, creep is a "time-dependent" deformation. PDF | On Jan 1, , Jindrich Fornusek and others published Creep and stress relaxation of pre-stressed GFRP tendons in concrete structures | Find, read and cite all the research you need on.