PipeTrenchMultipleLayers

The PipeTrenchMultipleLayers subassembly has a single pipe in a trench and a layer of material encasing the pipe.

This subassembly allows volume calculation of bedding base, pipe zone, and granular backfill. The pipe is encased in a layer of material right above the bedding. The center of the pipe will have a design profile. The depth will vary in the section of granular backfill; the others will be a constant. All of the depths, widths, and diameters will change from trench to trench. The depth of the trench will vary along the alignment since it is measured from the bottom of the trench to the target surface.

Attachment

By default, the attachment point is the center of the pipe.

Input Parameters

Note: All dimensions are in meters or feet unless otherwise noted. All slopes are in run-over-rise form (for example, 4 : 1) unless indicated as a percent slope with a “%” sign.

Parameter

Description

Type

Default

Bottom Width Bottom width of the pipe trench. Numeric, positive

3 ft

1 m

Pipe Diameter Pipe diameter. Numeric, positive

0.667 ft

0.2 m

Bedding Depth Depth of the pipe bedding under the pipe invert. Numeric, positive

0.75 ft

0.2 m

Pipe Encasement Material Depth Depth of pipe bedding over the pipe invert. Numeric, positive

2 ft

0.6 m

Target Surface Slope X : 1 slope of the trench sideslopes. Numeric, positive

1 (: 1)

Target Parameters

This section lists the parameters in this subassembly that can be mapped to one or more target objects. For more information, see To Specify Corridor Targets.

Parameter

Description

Status

Daylight Surface Name of the daylighting surface. The following object types can be used as targets for specifying the surface: surfaces. Required

Runtime Logical Assignments

None.

Output Parameters

None.

Behavior

The elevation of the bottom of the trench is calculated as the profile grade line elevation minus half the pipe diameter plus the bedding depth. The horizontal trench bottom link is placed symmetrically about the attachment point offset at that elevation. The pipe encasement material depth is used to provide for the material around the pipe. The side slopes are extended upward to the existing surface. The horizontal bedding link is placed at the given depth above the trench bottom.

Layout Mode Operation

In layout mode, this subassembly draws a trench.

Point, Link, and Shape Codes

The following table lists the point, link, and shape codes for this subassembly that have codes assigned to them. Point, link, or shape codes for this subassembly that do not have codes assigned are not included in this table.

Point, Link, or Shape

Code

Description

P1 PipeBottom Bottom of pipe
P2 BeddingBottomCenter Center of bedding bottom
P3 PipeBackfillBottom_In Inside pipe backfill bottom
P4 PipeBeddingBottom_In Inside pipe bedding bottom
P6 PipeBeddingBottom, Datum Pipe bedding bottom
P7 PipeBackfillBottom_Out Outside pipe backfill bottom
P8 PipeCenter Center of pipe
P11 Pipe
P12 PipeTop Top of pipe
P13 Pipe
P15 TopBackfill_In Inside top of backfill
P16 TopBackfill_Out Outside top of backfill
P17 Hinge, Top
P18 Top
L1, L5 PipeBackfillBottom Pipe backfill bottom
L2, L4 PipeBedding Pipe bedding
L3 PipeBeddingBottom, Datum Pipe bedding bottom
L6 - L7 Pipe
L8 - L9 Backfill
L10 TopBackfill Top of backfill
L11 TrenchSlopeInner Inner trench slope
L12 TrenchSlopeOuter Outer trench slope
L13 TrenchTop, Top Top of trench
S1 PipeBedding Pipe bedding
S2 PipeBackfillMaterial Pipe backfill material
S3 TrenchMaterial Trench material

Coding Diagram