Required length for column anchors

1. When  piers (concrete columns) are used, concrete breakout capacity alone cannot transfer the significant level of tensile forces from the steel column to the concrete base (due to the small dimensions of the pier cross-section).
2. In these instances, steel reinforcement in the concrete is used to carry the force from the anchor rods. 
3. The reinforcement must be sized and developed for the required tensile strength of the anchor rods.
4. The anchor rod embedment lengths are determined from the  required  development  length  of  the  spliced  reinforcement. 
5. Hooks or bends can be added to the reinforcing steel to minimize development length in the breakout cone. 
6. Anchor rod embedment length equals the top cover to reinforcing (i.e. the distance from reinforcement to top of concrete), plus Ld  (or Ldh  if hooked) plus 0.75 times g (where g is the distance from the anchor to the reinforcement, both axially). 
7. The minimum length of the anchor is 17 times the rod diameter.

Crane bumpers

Runway bumpers act similarly to their automobile counterparts:

• They absorb kinetic energy of the crane's impact.

Bridge bumpers should be designed to resist the force resulting from the crane hitting the stop at 40% of the rated speed.

For top-running bridge cranes, a heavy bracket bolted to the top of the runway girder is used as a stop. The bracket either:

• has an attached bumper, or
• is designed to come in contact with a bumper installed on the crane's end truck.

Eventually, the force on the stop is transferred to the building structure and bracing.

Fin plate rotation capacity

Fin plate connections derive their rotation capacity from:

• bolt deformation (in shear)
• hole distortions (bearing)
• out of plane bending of the fin plate

In order to achieve adequate rotational capacity, it is necessary to proportion fin plate connections so that the following failure modes are prevented:

• bolt shear
• weld rupture
• tensile tearing of the fin plate

Floor vibrations (ULS)

The issue of vibrations is considered to be a serviceability criteria.
However:
On some occations, the phenomenon can be an ultimate limit state consideration.
This is the case for high dynamic forces, such as:

• gymnasiums
• dance halls
• areas of aerobic activity.

Stub girders

Architectural demands for square column grids with spacings up to 12 m (almost 40ft) led to the development of stub girder construction.

The stub girder comprises of:

• a bottom chord which acts in tension
• a series of short beams (the stubs) which connect the bottom beam to ...
• ... the top chord which is the concrete slab and acts in compression.
• secondary beams which span across the bottom chord, designed as continuous beams
• the voids created are used for services.

The major disadvantage of the system is that it requires temporary propping until the concrete has gained adequate strength for composite action.

Castellated beams

Castellated beams can be used effectively for:

• lightly serviced buildings
• aesthetic reasons, where the structure is exposed

Composite action in castellated beams does not significantly increase the strength of the beams, but does increase their stiffness significantly.

Note finally that castellated beams have limited shear capacity and are thus best used as secondary beams.

LTB and cross-section

Cross-sections with:

• greater bending stiffness about the minor z-axis and
• greater torsional stiffness: 

have a greater lateral torsional buckling resistance.