Pipe Properties
- Becca Alford (Unlicensed)
Analytics
Pipe Shape
Circular: For circular shapes the only required inputs are the inner diameter and the wall thickness.
Elliptical: For elliptical shapes, in addition to the wall thickness you must also input four parameters to define the shape shown in the figure below. Note that elliptical pipe geometry must meet the geometry check as shown in the figure.
Inside Radius, Springline: This value is the distance shown as R1 in the figure above.
Inside Radius, Crown/Invert: This value is the distance shown as R2 in the figure above.
Horizontal Offset: This value is the horizontal distance u from the center of gravity of the pipe to the origin of radius R1.
Vertical Offset: This value is the vertical distance v from the center of gravity of the pipe to the origin of radius R2.
Materials Properties
Steel Reinforcing Yield Strength: Specified stress at yield of the steel reinforcing.
Reinforcing Type: Input a 1 (smooth wire), 2 (smooth welded wire fabric), or 3 (deformed welded wire fabric, deformed bars or any reinforcing with stirrups).
Number of Layers: This is currently not available for the user to change, and has been hard coded to 1.
Design Concrete Strength: Compressive strength of the concrete at the time of delivery.
Concrete Density: Density of the concrete.
Soil Pressure Distribution:
The user has four options to select from: Heger, Radial, Uniform/Automatic, and Uniform/Manual.
Heger: For the Heger method, the loads are applied using one of four Heger soil pressure distributions for the appropriate standard installation type (see Figure 3-1).
Radial: For the Radial load system, the loads are applied to the pipe as sinusoidal distributed normal pressures. This system is commonly referred to as the Olander pressure distribution.
Uniform/Automatic: For the Uniform/Automatic load system, the Loads are applied as vertical and horizontal uniform pressures on the top, bottom and sides of the pipe. This is commonly referred to as the Paris pressure distribution.
Uniform/Manual: The Uniform/Manual load system is an extension of the Uniform/Automatic load system, allowing the user more control over the applied soil pressures. Pipe will be analyzed and designed for the uniform pressures specified on screen combined with pipe dead weight, fluid load and live load if specified by the user. Surcharge loads maybe considered using this option.