Quiz 1 Distribution

      95                                                                     
      95                                                                  
      95                                                                  
      94                                                                  
      94                                                                  
      94                                                                  
      94                                                                  
      94                                                                  
      94                                                                  
      94                                                                  
      94                                                                  
      94                                                                  
      93                                                                  
      93                                                                  
100   93                                                                  
100   93                                                                  
99    93   88   84                                                      
98    93   88   84                                                      
98    92   88   84                                                      
98    92   88   82                                                      
98    92   87   82                                                      
97    92   86   81                  65                              
97    91   86   81             69   65   59                        
97    91   86   80        73   69   63   56                        
96    91   85   80   77   72   68   60   55   49   31   22   14

Mean: 83.5, Median 91

Quiz 2 Distribution

                84      
                84      
                84      
100        89   83      
 99   94   89   83      
 99   94   88   82      
 97   93   88   82      
 97   93   86   81   79                              
 96   93   86   81   79                              
 96   93   86   81   78        69   64                     
 95   92   86   80   77        66   63   57                  
 95   90   85   80   77   71   66   61   57   51   47   42             17
 95   90   85   80   75   70   65   60   55   51   47   42   35   34   16

Problem 1

It would be better if the sketch of the redesign included the diagonal members, but the comment concerning additional members for stability is enough.

Problem 2

A few people assumed that the k-factor for the column was 0.7. The deflected shape shows that the column is free to rotate at both ends, but is braced against sidesway, so k = 1.0.

Problem 3

Problem 4

a)

In addition to pointing out that converging centerlines avoided moment in the structure, a complete answer also described a problem that the moment creates (e.g. bending stress, in this answer).

b)

A good answer to this question included both a verbal description and sketches.

c)

d)

Nice visual effects.