PRP - Tool

	Clay 1 [CL & CL-ML]		Clay of Medium to Low Plasticity, LL < 50, < 25% Coarse Particles

	Silt 1 [ML & ML-CL]		Silt of Medium to Low Plasticity, LL < 50, < 25% Coarse Particles

	Clay 2 [CL]		Clay of Medium to Low Plasticity w/Sand or Gravel, LL < 50, 25-50% Coarse Particles

	Silt 2 [ML]		Silt of Medium to Low Plasticity w/Sand or Gravel, LL < 50, 25-50% Coarse Particles

	Coh-Gran [GC & SC]		Cohesive Granular Soils, > 50% Coarse Particles

	Sand Silt [GM & SM]		Sand or Gravel w/Silt, > 50% Coarse Particles

	Good Sand or Gravel [SW, SP, & GW]		Clean Sand or Gravel, > 95% Coarse Particles

1.5 : 1 is recommended as an explicit factor of safety for calculating restrained lengths in most installations. This factor, combined with the conservative values used in these calculations, generate very conservative restrained lengths. Severe conditions and critical installations may require higher factors.

	1 : 1
	1.5 : 1
	2 : 1
	2.5 : 1
	3 : 1

Type 2	Type 3	Type 4	Type 5

Flat-bottom trench. Backfill lightly consolidated to centerline of pipe.	Pipe bedded in 4-inch minimum loose soil. Backfill lightly consolidated to top of pipe.	Pipe bedded in sand, gravel, or crushed stone to depth of 1/8 pipe diameter, 4-inch minimum. Backfill compacted to top of pipe.(Approximately 80% Standard Proctor, AASHTO T-99.)	Pipe bedded to its centerline in compacted granular material, 4-inch minimum under pipe. Compacted granular or select material to top of pipe.(Approximately 90% Standard Proctor, AASHTO T-99.)

Restrained length calculations are based on the highest pressure that the pipeline will be subject to. Since test pressures are typically higher than the operating pressure, they are used in the calculations. Please enter a test pressure between 50 psi. and 350 psi.

This program supports the nominal sizes of 2" through 48", standardized mechanical joint fittings.

	Horizontal Bend
	Vertical Offset
	Tee
	Reducer
	Dead End

The restrained length calculations performed by this program are applicable to fittings whose restrained lengths do not interfere with the restrained lengths of other fittings. When restrained lengths do overlap, the designer must evaluate the combination as a whole. In some instances, combinations of fittings act to cancel some thrust forces, thus simplifying the necessary calculations.

	90°
	45°
	22°
	11°

	90°
	45°
	22°
	11°

Like the depth of bury entered in the Data Input Screen, the low side depth of a vertical offset is measured in feet to the top of the lower pipe. This program is able to calculate restrained lengths for pipelines buried up to 48 ft.

In a restrained joint system, the force at the tee is balanced by the soil in two areas. The first is the area of the pipe that is behind the tee. This is the area in which a thrust block would normally be poured. The restrained length of pipe Lr, along the run of the tee and on each side of the tee, encounters passive bearing resistance from the soil that acts perpendicularly to the tee. The restrained length along the branch of the tee connection, Lb, provides frictional resistance that involves the entire circumference of the branch piping.

The minimum attached length of pipe (Lr) to extend in each direction along the run of the tee is a user specified quantity and this program is used to calculate the restrained length along the branch (Lb). The length of pipe (Lr) must be of solid pipe without joints, fittings, etc. Consideration in specifying this length must be given not only to the job layout, but also to the practicalities of installation.

	Ductile Iron		Ductile Iron Pipe
	PVC		Polyvinyl Chloride (PVC) Pressure Pipe
	Polywrap Ductile Iron		Ductile Iron Pipe in Polyethylene Encasement


1. Name the project file:	.txt

2.