COLLAPSE OF TEXAS TOWER NO. 4 37 



Mr. Anderson. Well, I think that it is apparent to all that there 

 were certain inadequacies. But I have no opinion. In other words, 

 I did not participate in formulating the design criteria. 



Mr. Kendall. Well, for example, Mr. Anderson, would you have 

 used pin connections if you had been designing this tower ? 



Mr. Anderson. Again, that is very difficult to say. I would ques- 

 tion very much that we would. 



Senator Stennis. What was that, please ? 



Mr. Anderson. I said I would question that we would be using pin 

 connections. 



Mr. Kendall. Why wouldn't you have used them ? 



Mr. Anderson. Tliis would be a matter of structural design, and 1 

 do not believe that we would approach it quite that way. This system 

 of bracing, as I know it, was a patented design, and I do not know 

 whether pin connections were part of that or not. 



Mr. Kendall. I did not get that last statement. 



Mr. Anderson. I say, as I know it, this bracing system in which 

 these pin connections were used was a patented design, as I have been 

 told. And whether the pin connections are part of that patented de- 

 sign, I am not in a position to say. 



Mr. Kedall. Well, can you explain briefly what we are talking 

 about when we are talking about pin connections, as distinguished 

 from welded connections ? 



Mr. Anderson. I do not think it shows on the m-^odel. 



Mr. MiNNiCH. It is not shown on the model. 



Senator Stennis. Were you sworn a while ago ? 



Are there any others to testify here on these points ? 



swearing in of additional witnesses 



Mr. Anderson. Mr. Holland may. 

 Senator Stennis. All right. 

 Hold up your right hand. 



Do you solemnly swear that your testimony in this hearing will be 

 the truth, the whole truth, and nothmg but the truth, so help you God ? 

 Mr. MiNNiCH. I do. 



Mr. ROLLAND. I do. 



Mr. MiNNicH. John Minnich, chief structural engineer. 



Mr. RoLLAND. Martin G. Rolland, chief mechanical engineer. 



Mr. Minnich. Do you want me to answer that ? 



Mr. Kendall. Yes, sir ; if you will, Mr. Minnich. 



Mr. Minnich. A pin connection is simply a structural connection 

 in which a steel pin is placed in previously drilled holes to make a 

 connection, in contrast to other types, such as welding, where the 

 members are joined directly by means of welding. 



Is that clear enough ? 



Mr. Kendall. Since the subject is going to be discussed, I thought 

 we ought to have something in the record on this point. 



Is one apt to be more rigid than the other ? I am still discussing a 

 weld as against a pin connection ? 



Mr. Minnich. Generally speaking, a welded connection is character- 

 ied by a greater rigidity than a pin connection. Sometimes it is 

 advantageous not to have too much rigidity, and in that case, a pin is 



