56 



Figure 43 



Photographs of the TMB 4l-Inch Planing Float 

 after Submergence Tests 



The reinforcing-rod welds have failed in the top surface of the float, and the rods have been pushed 

 / through. The flat surfaces have failed completely, while the curved surfaces at the bow 

 do not show excessive deflections. 



the rods be reinforced with small bushings to provide greater welding area. 

 However, the additional cost did not warrant this step for the surface floats. 



Based on these tests and the design used herein, and assuming that 

 failure will occur in the welds, as it did on this float, a safe maximum depth 

 of submergence can be assumed to be 75 feet of sea water, provided that an 

 internal prestresslng pressure of 8 pounds per square inch is used. A search- 

 ing analysis of the strain data for purposes of providing design criteria is 

 not warranted, however, because of tne lack of essential measurements. 



