LECPres - Precast/Prestressed Concrete Beam Design
- Handles any combination of prestressing strand and/or mild reinforcing.
- Built-in torsion analysis follows ACI or PCI procedures.
- Straight and single or double strand depression
- Automatic or manual prestress loss calculations
- Camber prediction at release, erection and final, with and without live load
- Bi-linear deflection calculation is used when cracking stress is exceeded
- Convenient built-in section property calculator
- Transformed section is used for stress calculations
- Two stage topping thickness option
- Supports sloped top flange
- Allows cantilevers at one or both ends
- Provides top steel required for IT and L beams
- Option for rebar anchorage at ends of member
- Multiple uniform, concentrated and trapezoidal loads, even concentrated moments. Any of these can be eccentric.
- Can specify percent of live load to apply to service load stresses (useful for parking deck design)
- Easy to use Windows graphical interface with print preview Compact three page printout lists all information
Best of all, one year of telephone support and maintenance updates are included in the initial license fee.
A free trial version is available. Sign and fax or mail back the evaluation license agreement and we will send it to you. Note that the trial period expires after 30 days and that the software has to be erased if a license is not purchased. The trial version functions identically to the licensed version.View some screen captures of the program in action
Ultimate strength design and load factors are based on ACI 318-99 or 318-08.
All shear, moment, stress and deflection values are calculated at 40 equally spaced points along the member span.
Beam Analysis for Shear and moment at 40th Points: The internal forces are determined by an approximate procedure. An equilibrium check is performed at 40 points along the span.
Shear strength is calculated according to ACI 318-08 Section 11.4. Shear reinforcement requirements are based on Section 11.5 and torsion is based on Section 11.6.
Moment strength is based on strain compatibility and ACI 318-08 Section 18.7. The compression block can extend into the topping gap, the beam flange, the beam flange-to-web sloped portion and the beam web. Prestressing strand development length is based on Section 12.9.
End release stresses are calculated at the point of prestress transfer equal to 50 strand diameters from the end of the member. Allowable release and service load stresses are based on ACI 318-08 Section 18.4, with the exception of allowable service load tension stress, which is input by the user. Prestress losses are calculated using Section 4.7 of the PCI Design Handbook.
The moment-area method is used to calculate flexural displacements. When the bottom tension stress exceeds 12 * SQRT(F'c) bi-linear behavior is assumed, based on the PCI Handbook, Section 4.8.3.
Building Code Requirements for Structural Concrete (ACI 318-08), American Concrete Institute, Detroit, MI.
PCI Design Handbook, Seventh Edition, Precast/Prestressed Concrete Institute, Chicago, IL.