(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Concrete highway slabs are poured in lengths of 10.0 m. How wide should the expansion gaps between the slabs be at a temperature of 20 degrees C to ensure that there will be no contact between adjacent slabs over a temperature range of -24 C to 45 C?

2. Relevant equations

Change in length= (coefficient of linear expansion)(initial length)(change in temp)

(I represented the coeff by α)

α of concrete=12x10^-6 degrees C^-1

3. The attempt at a solution

Change in length=(12x10^-6)(10)(-25-20)=-0.0054 m (is it ok that this is negative?)

Change in length=(12x10^-6)(10)(45-20)=0.003

Now, do I add these values to get the total change in length?

(-0.0054m)+(0.003m)= -0.0024m

I understand the equation and the idea of it, but I don't know if I solved the problem correctly.

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Thermodynamics of concrete in a highway

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