Steel Connection Design Spreadsheet

Steel Connection Design Spreadsheet

Steel Connection is divided into two common methods: bolting and welding.
Bolting is the preferred method of Steel connecting members on the site. Staggered bolt layout allows easier access for tightening with a pneumatic wrench when a connection is all bolted.  High strength bolts may be snug-tightened or slip-critical. Snug-tightened connections are referred to as bearing connections Bolts in a slip-critical connection act like clamps holding the plies of the material together.Bearing type connections may have threads included ( Type N ) or excluded ( Type X ) from the shear plane(s).  Including the threads in the shear plane reduces the strength of the connection by approximately 25%.  Loading along the length of the bolt puts the bolt in axial tension. If tension failure occurs, it usually takes place in the threaded section.Three types of high strength bolts A325, A490 (Hexagonal Head Bolts), and F1852 (Button Head Bolt). A325 may be galvanized A490 bolts must not be galvanized F1852 bolts are mechanically galvanized. High strength bolts are most commonly available in 5/8” – 1 ½” diameters. Bolting requires punching or drilling of holes. Holes may be standard size holes, oversize holes, short slotted holes, long slotted holes

 Due to high costs of labor, extensive field -welding is the most expensive component in a steel frame. Welding should be performed on bare metal. Shop welding is preferred over field welding. The weld material should have a higher strength than the pieces being connected.Single-pass welds are more economical than multi-pass welds. The most economical size weld that may be horizontally deposited in one pass has 5/16”. Fillet welds and groove welds make up the majority of all structural welds. The strength of a fillet weld is directly proportional to the weld’s throat dimension. The capacity of a weld depends on the weld’s throat dimension and its length.

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Staircase Analysis and Design Spreadsheet

Staircase Analysis and Design Spreadsheet

Staircases provide means of movement from one floor to another in a structure. Staircases
consist of a number of steps with landings at suitable intervals to provide comfort and safety
for the users.

Types of Stairs
For purpose of design, stairs are classified into two types; transversely, and longitudinally
supported.
a- Transversely supported (transverse to the direction of movement):
Transversely supported stairs include:
§ Simply supported steps supported by two walls or beams or a combination of both.
§ Steps cantilevering from a wall or a beam.
§ Stairs cantilevering from a central spine beam.
b- Longitudinally supported (in the direction of movement):
These stairs span between supports at the top and bottom of a flight and unsupported at the
sides. Longitudinally supported stairs may be supported in any of the following manners:
a. Beams or walls at the outside edges of the landings.
b. Internal beams at the ends of the flight in addition to beams or walls at the outside edges of
the landings.
c. Landings which are supported by beams or walls running in the longitudinal direction.
d. A combination of (a) or (b), and (c).

e. Stairs with quarter landings associated with open-well stairs.

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Beam Analysis Spreadsheet

Beam Analysis Spreadsheet

The "BeamAnal" calculates Shear Force, Bending Moment and Deflection at 31 positions along the member length. Member Lengths can be a single span simply supported or a 2, 3 or 4 span continuous over middle supports. The analysis results are produced in a tabular form and are also plotted in 3 graphs for rapid comprehension.
The program uses usual equations for Shear Force, Bending Moment and Deflection equations along the member span. When middle supports are specified, simultaneous equations are set up and solved to calculate the middle support reactions.

The program internally works in consistent Force and Length Units. To help comprehend results, use of mixed units is allowed. Inertia and elastic modulus of the member section can therefore be defined in any units. Similarly, any desired units can be set deflection values. To specify units, go to the Units sheet and describe your own units of Force, Distance, Inertia, Modulus and Deflection. You need to calculate and specify conversion factors from consistent units to your chosen mixed units. Sample values are given for your guidance in this sheet. The units cannot however be mixed in one project file. Chosen units apply to all beams in the file. This means that if units are changed in the middle of building up a data file, beam properties for all beams need to be re-defined to match the chosen units.

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Design of Bridge Slab Spreadsheet

Design of Bridge Slab Spreadsheet

Reinforced Slab Bridges used For short spans, a solid reinforced concrete slab, generally cast in-situ rather than precast, is the simplest design to about 25m span, such voided slabs are more economical than prestressed slabs. Slab bridges are defined as structures where the deck slab also serves as the main load-carrying component. The span-to-width ratios are such that these bridges may be designed for simple 1-way bending as opposed to 2-way plate bending. This design guide provides a basic procedural outline for the design of slab bridges using the LRFD Code and also includes a worked example.
The LRFD design process for slab bridges is similar to the LFD design process. Both codes require the main reinforcement to be designed for Strength, Fatigue, Control of Cracking, and Limits of Reinforcement. All reinforcement shall be fully developed at the point of necessity. The minimum slab depth guidelines specified in Table 2.5.2.6.3-1 need not be followed if the reinforcement meets these requirements.
For design, the Approximate Elastic or “Strip” Method for slab bridges found in Article 4.6.2.3 shall be used.
According to Article 9.7.1.4, edges of slabs shall either be strengthened or be supported by an edge beam which is integral with the slab. As depicted in Figure 3.2.11-1 of the Bridge Manual, the #5 d1 bars which extend from the 34 in. F-Shape barrier into the slab qualify as shear reinforcement (strengthening) for the outside edges of slabs. When a 34 in. or 42 in. F-Shape barrier (with similar d1 bars) is used on a slab bridge, its structural adequacy as an edge beam should typically only need to be verified. The barrier should not be considered structural. Edge beam design is required for bridges with open joints and possibly at stage construction lines. If the out-to-out width of a slab bridge exceeds 45 ft., an open longitudinal joint is required.

Design of Bridge Slab Spreadsheet

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