RubCon Creep

In a situation that combines long-term compressive load and an aggressive environment, the mechanical properties of a material deteriorate because the complex influence of these factors is accompanied by a synergetic effect. Research on RubCon creep in these conditions was carried out on samples measuring 40 x 40 x 160 mm in the special chamber at a temperature of 20°C 2°C. Three series of samples were tested in different corrosion environments in water, in a 30% solution of a sulfuric... 

Resistance of fiber-reinforced RubCon to long-term loading is the principal criterion of its application as a structural material. We investigated creep of plain RubCon at compression earlier. Experiments were continued for the purpose of studying fibrous RubCon creep. 

The allowed us to obtain RubCon creep coefficients creep = ocreep/o c. The relationship of creep coefficients to time for the reinforced and plain RubCon samples is shown in Figure 2.56. 

Asymptotes of the curves give an indication of the fibrous RubCon creep limit. It is interesting to note that the creep coefficient of the plain RubCon creep = 0.77-0.78, whereas for fiber reinforced RubCon it is slightly below creep = 0.74-0.75. In this case the creep limit of fiber-reinforced RubCon at compression ccreep = 74.9-78.4 MPa exceeds the creep limit of plain material ccreep = 66-66.8 MPa. This phenomenon is... 

Creep Deformation of Plain RubCon at Long-Term Compressive Load... 

RubCon application in load-bearing structures is directly connected to the stress-strain state of a material under long-term loading action (creep). Creep of RubCon at compression was determined on samples measuring 40 x 40 x 160 mm. 

Two series of RubCon samples of type A and type B were tested. The creep curves are shown in Figures 2.39 and 2.40. 

FIGURE 2.45 Structural diagram of RubCon samples at compression (1) samples type A, (2) samples type B. (Reprinted from Yu. Potapov, O. Figovsky, Yu. Borisov, S. Pinaev, and D. Beilin, Creep of Polymer Concrete at Compressive Loading, J. Scientific Israel Technological Advantages 5, nos. 1-2 (2003) 1-10. With permission.)... 

Creep Deformation of Plain RubCon with a Combination of Long-Term Compressive Loading and an Aggressive Environment... 

Results of these experiments are shown in Figures 2.48-2.50. The obtained experimental data creep in RubCon samples were analyzed with the phenomenological theory of structural diagrams (Figure 2.51a-c). 

The analysis of structural diagrams shows that at creep in aggressive environments, the extent of a viscous phase in the composite structure is increased due to penetration of the environment into the material pores and its influence on the structure and rheological properties of RubCon. The increase of a viscous phase results in a decrease in strength and deformation characteristics of RubCon. 

To gain a better understanding of the influence of fiber reinforcement on creep of RubCon, we investigated the relationship between values of compressive stresses and creep deformations that are damped out with time. The analysis of the result diagrams (Figures 2.54 and 2.55) shows linear stress-strain dependence of fiber-reinforced and plain RubCon samples at short-term compressive loading. However, creep deformations of these samples do not linearly depend on compressive stress value due to highly elastic deformation of the polybutadiene binder. 

The mathematical model of creep deformations at long-term compressive loading agrees well with experimental results and can be put in a basis of design of RubCon load-bearing structures. 

Steel fibrous RubCon is a creep-resistant material the coefficient of creep at compressive load kCT 0.75. 

It is shown [18] that RubCon has high chemical resistance not only under normal operating conditions, but also at long-term compressive loading (creep) in aggressive environments. 

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