Polymer composites containing natural fibers are receiving growing attention as possible alternatives for composites containing synthetic fibers. The use of biodegradable matrices obtained from renewable sources in replacement for synthetic ones is also increasing. However, only limited information is available about the creep behavior of the obtained composites. In this work, the tensile creep...

Introduction Inertial effects are ubiquitous and unavoidable in stress-controlled rheometry. Many readers of this Bulletin will have seen the kind of phenomena shown in the experimental data of Figure 1. If the fluid is sufficiently viscoelastic, inertio-elastic 'ringing' events (i.e. damped oscillations) are observed in the angular displacement measured at the start of a creep test, as a resul...

Theoretical analysis and finite element (FE) simulation have been carried out for a constant specific load rate (CSLR) indentation creep test. Analytical results indicate that both the representative stress and the indentation strain rate become constant after a transient period. Moreover, the FE simulation reveals that both the contours of equivalent stress and equivalent plastic strain rate u...

The creep and recovery of 5% carboxyl-terminated butadiene acrylonitrile (CTBN) modified epoxy shape memory polymers (SMP) was studied. The results were compared with those for the unmodified epoxy SMP. The glass transition temperatures (Tg) were determined using Advanced Rheometric Expansion System (ARES). The creep behavior of the unmodified epoxy and 5wt.% CTBN modified epoxy SMP were studie...

Creep compliance measurements were shown to be effective in characterizing the elastic, retarded elastic, and viscous properties of polysulphide, silicone, and polyether impression materials. The test is particularly valuable in that the creep compliance was independent of load, allowing the mechanical properties to be represented by a single total creep compliance curve which can be used to de...

In this paper, the dynamic behaviour of a rail vehicle with single-wheel drive and brake modules is analysed. It is shown that in the wheelslide or wheelskid case, the linearised plant obtains an unstable pole whose location is determined by the shape of the current creep force curve. By considering possible variations in the shape of the creep force curve, the corresponding variation of the po...

We simulate the glide motion of an assembly of interacting dislocations under the action of an external shear stress and show that the associated plastic creep relaxation follows Andrade's law. Our results indicate that Andrade creep in plastically deforming crystals involves the correlated motion of dislocation structures near a dynamic transition separating a flowing from a jammed phase. Simu...

A new experimental method which allows the direct separation of the components of drying creep due to micro cracking and stress-induced shrinkage is developed, demonstrated and validated. The hasic idea is to compare the curL'CIture creep of heams suhjected to the same hending moment hut rery different axial forces. The results confirm that drying creep has two different sources: microcracking ...