em2901.chp:Corel VENTURA - Publications, US Army Corps of ...

EM 1110-2-2702
1 Jan 00
Figure 3-6. Example of wire rope hoist system
(4) Stressed skin gates. Stressed skin gates are a type of orthotropic gate in which the skin plate
assembly is considered to be a shell or tubular structure spanning between trunnion arms. The skin plate is
stiffened with horizontal and vertical diaphragms and intermediate stiffening members (usually horizontal
tee sections parallel to the intermediate or midlevel horizontal diaphragm). As with other orthotropic
gates, this type of gate can save material and gate weight, but fabrication and maintenance costs are often
higher.
(5) Truss-type or space frame gates. Three-dimensional (3-D) truss or space frame gates were sometimes
used in early tainter gate designs in the 1930s and 1940s. These early gates were designed as a series
two-dimensional (2-D) trusses and were referred to as truss-type gates. They were typically as heavy or
heavier than girder designs and fabrication and maintenance costs were very high. For this reason they
were not adopted as a standard design. More recently, the use of computer designed 3-D space frame gates
constructed with tubular sections has been investigated and may be practical in some situations.
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