Transcription of PRECAST CONCRETE PIPE
1 PRECASTCONCRETE PIPEWHY PROVIDEGUIDELINES? Past problems. Was tedious to keep track of variables. Was easy to make mistakes. Wanted a design tool to Minimum Structure Size. Maximum Angle into RectangularStructures. Minimum Angle between Pipes enteringRound Structures. Minimum pipe SIZE The PRECAST opening is typically 6 incheslarger than the pipe s outside 4-2ofStorm Drain HandbookAugust 2000 Values based on Openings for CONCRETE PipeMINIMUMSTRUCTURE SIZEM inimum DimensionsFor StructuresMaximum Angle (Skew) into aRectangular StructureMAXIMUM ANGLE (SKEW)INTO A RECTANGULAR STRUCTURE12 PRECAST Opening6 OD Pipe60 PRECAST Opening54 OD Pipe6 StructureWallStructure WallGood practice to allow 2" ofcontruction yRODPipeCos= CosODPipeR=RTolerance = PRECAST Opening R yMAXIMUM ANGLE (SKEW)INTO A RECTANGULAR STRUCTUREE xample:Given.
2 24 CONCRETE pipe at 17 degree skew Structure Wall Thickness = 8 A 24 CONCRETE pipe has a 30 outsidediameter and a 36 PRECAST = PRECAST Opening R y = 36 (30 /Cos 17o) 8 x Tan 17o= MAXIMUM ANGLE (SKEW)INTO A RECTANGULAR STRUCTURET able 4-3 of Storm Drain Handbook August 2000 Values are based on 2 inches of construction tolerance,structures with 8-inch walls and CONCRETE pipe Round Structure or Rearrange Pipesif these Angles are Exceeded. MAXIMUM ANGLE (SKEW)INTO A RECTANGULAR STRUCTUREM inimum Angle Between PipesEntering Round StructuresPlan ViewStructurePipe #1 pipe #2 MINIMUM ANGLE BETWEEN PIPESENTERING ROUND STRUCTUREMINIMUM ANGLE BETWEEN PIPESENTERING ROUND STRUCTUREPipe #1 PRECAST OpeningPipe #2 PRECAST OpeningPlan ViewPipe #1 Half anglePipe #1 Half )(RadStructOpening21 AngleHalfSin=Separation AngleYields 2 InsideHALF ANGLE DIAGRAMT able 4-6of Storm DrainHandbookPartial ViewRead Notes!
3 MINIMUM ANGLE BETWEEN PIPESENTERING ROUND STRUCTURE Minimum Cover Requirements of Index205. Strive to maintain a 6-inch precastsection above the pipe opening whileavoiding Grates, Inlet Tops and DEPTHMINIMUM DEPTHMINIMUM DEPTHMINIMUM DEPTHMINIMUM DEPTHMINIMUM DEPTHMINIMUM DEPTHMINIMUM DEPTHI nlet Types B & G were not included due toplanned design 4-4 of Storm Drain Handbook (partial view)** Read Notes **MINIMUM DEPTH Index 220: Inlet Type S; Recommended Max pipein long wall should be 30 , not 36 Index 221: Inlet Type V; Recommended Max pipein long wall should be 30 , not 36 Index 230: Inlet Type A; Recommended Max pipein long wall should be 18 , not 24 FUTURE CHANGES TO THE ROADWAY& TRAFFIC DESIGN STANDARDS Index 232: Inlet Type C; Recommended Max pipein long wall should be 18 , not 24 Index 232: Inlet Type E.
4 Recommended Max pipein long wall should be 36 , not 42 Index 234: Inlet Type J; Recommended Max pipein long wall should be 30 , not 36 FUTURE CHANGES TO THE ROADWAY& TRAFFIC DESIGN STANDARDS
