Answer Happy

Figure 1 shows a 4-element linear viscoelastic phenomenological model. Equation (1) describes the stress applied to this model (a creep test) and Equation (2) shows the resulting strain predicted by the model as a function of time. n1 E2 n2 [ní koments www E Figure 1. A 4-element linear viscoelastic phenemonological model. Eq (1) o(t)=0,4() Y(t) = 700) -- 0+ (1-e1/6) t + Eq (2) EE m2 Note, the Young's moduli of Spring 1 and Spring 2 in Figure 1 are 40,000 Pa and 50,000 Pa respectively, while the viscosities of Dashpot 1 and Dashpot 2 are 25,000 Pas and 100 Pas respectively. A stress of 3000 Pa is applied to the model. Determine the strain in this system when the time = 3 s. Give your answer correct to 3 decimal places (hint: you'll need to know or look-up the definition of the retardation time to answer this question).