1.035  Mech of Structures & Soils

I have posted some lecture notes on structural design, which covers some of the material we have covered in the last few classes.

On a related matter, at the end of today' class in the example of a doubly clamped beam subjected to uniform load w, I mistankingly wrote (of the top of my head) the moment at the center  as w*L^2/8. It should have been W*L^2 / 24, which means that it is only half as large as that at the supports. The implication is that the beam will first yield (simultaneously) at the two supports, and later on at the middle. However, the ultimate configuration will be the same as I had on the board, and so will be the failure mode. Since 1/12+1/24 = 1/8  (= the reason for my confusion), it follows that 2*M_u=w_ultimate*L^2/8, so w_ultimate =16*M_ultimate/L^2, which is the largest distributed load that the beam can resist.

Have a nice Thanksgiving!

The Scheduling Office has informed us that the final exam for 1.035 will take place on Wednesday Dec. 17, from 9-12 AM in Room 32-144. Please take this date into consideration when making your holiday travel plans.