36 COLLAPSE OF TEXAS TOWER NO. 4 
computed wind velocities and wave heights during the 20 years im- 
mediately preceding the tower’s erection, although not necessarily in 
combination. 
Committee conclusion.—The design criteria was clearly inadequate. 
Those charged with the responsibility for its determination, the 
Navy’s Bureau of Yards and Docks and the structural design engi- 
neers—the firm of Moran, Proctor, Mueser & Rutledge—underesti- 
mated the environmental wind and wave forces to which the tower 
would be exposed during its anticipated 20-year life in the Atlantic 
Ocean. The forces of wind and wave which exceeded this criteria 
should have reasonably been foreseen on the basis of the findings from 
the feasibility study conducted by the structural design engineers 
and approved by the Navy. The structural design engineers miscal- 
culated in believing that the design criteria was reasonable and safe. 
soe8 
Finding.—The patented Kuss tip-up method, by which the template, 
consisting of the legs and their bracings, was fabricated in port, floated 
to the site in a horizontal position, and upended to a vertical position 
was utilized in the erection of Texas tower No. 4. This was the first 
time the method had been used in erecting an offshore structure and 
it has been used only once since that time. The inventor, Mr. Kuss, 
became an employee of the structural design engineering firm shortly 
after the design contract was awarded to that firm. 
Committee conclusion—The subcommittee seriously questions the 
wisdom of using for the first time, on a structure such as tower No. 4, 
an untried, untested process which had not even been considered as 
a method of erection by the Navy’s Bureau of Yards and Docks until 
after the inventor thereof was employed by the structural design 
engineering firm. 
IV 
Finding.—Several changes which deviated from the design specifi- 
cations were recommended by the contractor, J. Rich Steers, Inc.- 
Morrison-Knudsen Co., and approved by the structural design engi- 
neers. QOne consisted of an increase in the tolerances between the pins 
and the connections into which they were inserted for connecting the 
braces. Another change permitted the substitution of the permanent 
platform for the originally intended temporary one. This change 
had two major consequences in that it meant that the heavier perma- 
nent platform would be raised on legs which had neither been em- 
bedded nor stiffened or reinforced with concrete and that the upper 
panels of diagonal bracing had to be folded down and secured to 
the horizontal braces of the next lower panels. The structural design 
engineers first approved and later disapproved the method proposed 
by the contractor in lashing down the diagonal struts. Prior to tip-up, 
two of these diagonal braces were damaged and lost. 
Committee conclusion.— 
1. The damage and loss of these braces resulted either from a de- 
ficiency in the designed method of erection as changed, from an in- 
adequate or insecure lashing down of the braces, or from exceptional 
stresses in upending the template in position. The structural design 
engineers miscalculated the effect of the seas during the tow and tip-up 
