The URL can be used to link to this page

Home My WebLink AboutDrainage Reports - 05/03/1995INC. Engineering Consultants 209 S. Meldrum Fort Collins, Colorado 80521 303/482-5922 FAX: 303/482-6368 April 26, 1995 Mr. Basil Hamdan City of Fort Collins Utility Services, Stormwater 235 Matthews Street Fort Collins, CO 80522 RE : Revision to Drainage Utility at Oakridge Business Park, Seventeenth Filing Dear Basil, This letter and the attached channel calculations are being submitted to explain a revision on the Drainage Plan for the Oakridge Business Park, Seventeenth Filing. Due to some grading conflicts, the developer of this property has elected to use a trickle pan as opposed to the previously designed subdrain for section 'E'. The reason for this is the tenants of the southwest lot want to maximize the amount of room available for a parking lot on the south side of their building. The subdrain option was determined to be too wide, so a trickle channel was proposed. This change does not alter the intent of the drainage plan in any way. Attached is a printout of the channel analysis, showing the new trickle channel, and the calculation used to arrive at an effective 'c' value. These changes have been added to the Drainage Plan and clouded to reflect the fact that they are revisions. Due to layout changes, it has become necessary to relocate.the channel along the east property line of this site. Per our conversation on April 25, 1995, included is the new mylar for the Drainage and Grading plan of the Oakridge Business Park, Seventeenth Filing. Attached is a printout showing the calculations used in sizing the two pipes on the east side of the property. Two 24 inch diameter RCP's are to Denver 303/458-5526 be laid side by side in order to pass the design flow for the ditch. The use of pipes here was chosen so that PRPA would have complete access to their power pole, and to avoid an "S" curved ditch along this side of the property. There will be approximately 0.5 feet of cover over these pipes. Another printout has been included from an evaluation done to determine if this is acceptable for an HS-20 loading. The attached printout shows that this 0.5 feet is acceptable. This design has been approved by PRPA and a copy of the legal description for this new easement has been forwarded to them. The legal description for the drainage easement this new channel has been included with this memo. Please call me if you have any questions regarding this memo. Sincerely, RBD, INC. Prepared by: Perry E. Cabot Project Engineer I Reviewed by: LQ Stan A. Myers, P.E. Project Manager c RBD INC. ENGINEERING CONSULTANTS CHANNEL RATING INFORMATION OAKRIDGE BUS PARK 17 STA 0.00 4.00 5.00 6.00 10.00 'N' VALUE 0.050 ELEVATION AREA (feet) (sq ft) ELEV MOO 19.00 18.96 19.00 20.00 SLOPE (ft/ft) ------------- 0.0050 VELOCITY DISCHARGE (fps) (cfs) FROUDE NO. Q,o 2.20 cfS (32too 4- ✓3% _ 6.93 cPS 19.06 0.2 0.4 0.06 0.24 19.16 0.5 0.6 0.26 0.27 19.26 0.8 0.7 0.60 0.28 19.36 1.3 0.9 1.D9 0.29 r 19.46 1.8 1.0 1.75 0.30 �o L O•S 19.56 2.4 1.1 2.60 O X 19.66 3.1 1.2 3.65 0.32 Q,00 Ld O .g 1 19.76 3.9 1.3 4.92 0.32_ f 19.86 4.7 1.4 6.42 0.33 19.96 5.6 1.4 8.18 0.33 13�r_S � Cb•�1i O.0(ol. � r r�r II�(21�0.o - O.Z I PROGRAM SAMM- OAKRIDGE BUSINESS PARK, SEVENTEENTH PAGE 1 SSSSSSSSS AAAAAAAAA MMM MMM MMM MMM SS AA AA MM M M MM MM M M MM SSSSSSSSS AAAAAAAAA MM M MM MM M MM SS AA AA MM MM MM MM SSSSSSSSS AA AA MM MM MM MM P R O G R A M S A M M AMERICAN CONCRETE PIPE ASSOCIATION VERSION 2.0 - 1 SEPTEMBER 1990 Program SAMM computes earth loads on concrete pipe in accordance with the methods presented in the Concrete Pipe Design Manual (March 1990) and the Concrete Pipe Handbook (January 1988), published by the American Concrete Pipe Association. The user must select input values suitable to his specific installation. The information presented in the computer output is for review, interpetation, application and approval by a qualified engineer who must assume full responsibility for verifying that said output is appropriate and correct. There are no express or implied warranties. The use of this product does not constitute endorsement by ACPA or any other agents. DATE: 04/26/95 DESIGNER: F'EC. PROGRAM SAMM- OAKRIDGE BUSINESS PARK, SEVENTEENTH PAGE 2 PROGRAM SAMM D-LOAD REQUIREMENTS FOR A 24 IN. DIAMETER CIRCULAR PIPE ******************************************************************************** P I P E D A T A -------------------------------------------------------------------------------- DIAMETER (in.) 24.00 WALL THICKNESS (in.) 3.250 I N S T A L L A T I O N C O N D I T I O N S -------------------------------------------------- MINIMUM DEPTH OF FILL (ft.) MAXIMUM DEPTH OF FILL (ft.) SOIL DENSITY (lb/Cu. ft.) BEDDING CLASS INSTALLATION TYPE TRENCH WIDTH (ft.) SOIL LATERAL PRESSURE/FRICTION TERM (KMUI) PARAMETERS TO COMPUTE TRANSITION WIDTH POSITIVE PROJECTION RATIO POSITIVE SETTLEMENT RATIO SOIL LATERAL PRESSURE/FRICTION TERM (KMU) SOIL LATERAL PRESSURE COEFICIENT A D D I T I O N A L L 0 A D S ----------------------------------------------------- LIVE LOAD NO SURCHARGE LOAD 0.50 5.00 120.0 B TRENCH 3.00 0.1924 1.00 0.50 0.1924 0.33 ------------------- AASHTO HS-20 F A C T O R S O F S A F E T Y -------------------------------------------------------------------------------- FACTOR OF SAFETY ON 0.01 INCH CRACK D-LOAD (EARTH,LIVE) 1.00; 1.00 FACTOR OF SAFETY ON ULTIMATE LOAD (EARTH,LIVE) IN ACCORDANCE WITH ASTM C 76 DL.01 LESS THAN 2000 LBS/FT/FT 1.5 DL.01 GREATER THAN 3000 LBS/FT/FT 1.25 DL.01 BETWEEN 2000 AND 3000 LBS/FT/FT INTERPOLATED R E S U -------------------------------------------------------------------------------- L T S O F A N A L Y S I S PIPE ------EARTH LOAD----- LIVE SURCH TOTAL BED D-LOAD DEPTH ARCHING >TRANS LOAD LOAD LOAD LOAD FACT (REQUIRED 0.01 in. ULT. (ft.) FACTOR (lb/ft) (lb/ft) (lb/ft) (lb/ft) (lb/ft/ft) 0.5 1.04 Y 158. 4121. 0. 4279. 1.90 1126. 1689. 1.0 1.08 Y 329. 3033. 0. 3362. 1.90 1327. 1.5 1.07 N 491. 2429. 0. 2920. 1.90 768. 1153. 2.0 1.04 N 635. 1802. 0. 2437. 1.90 641. 962. 2.5 1.01 N 770. 1285. 0. 2055. 1.90 541. 811. 3.0 0.98 N 896. 938. 0. 1835. 1.90 483. 724. 3.5 0.95 N 1015. 773. 0. 1788. 1.90 471. 706. 4.0 0.92 N 1126. 649. 0. 1775. 1.90 467. 701. 4.5 0.90 N 1231. 553. 0. 1784. 1.90 470. 704. 5.0 0.87 N 1329. 478. 0. 1807. 1.90 475. 713. o.0, IFOe CL$P,GS 2,c,p is 1350 16/�' i �.Ct �/ oi< G.t..A6S 7m ec-e VJIt� Wp�K Ce O,S' DEEP UIJPEe- kcS-2-A U o;pDl)I }JejI OPEN CHANNEL FLOW ANALYSIS: FLOW IN A PIPE Developed by Or James Guo, Civil Eng Dept, U of Colorado at Denver Metro Denver Cities/Counties and UD&FCD Pool Fund Study User= KEVIN GINGERY RBD INC. FT. COLLINS COLORADO ............................. ON DATE 04-27-1995 AT TIME 07:53:58 * PROJECT TITLE: OAKRIDGE PIPES * DESIGN INFORMATION IPE (EQUIVALENT) DIAMETER(INCHES) _ IPE ROUGHNESS MANNING N = IPELINE SLOPE (FT/FT) _ ESIGN FLOW RATE (CFS) * NORMAL FLOW CONDITIONS: 24.27 USE. 2`�„ 'PIPS 0.013 0.0080 20.90 LOW CENTRAL ANGLE (DEGREE) = 360.00 LOW DEPTH (FEET) = 2.02 LOW AREA (SO FEET) = 3.21 LOW VELOCITY (FPS) = 6.51 PECIFIC ENERGY (FT) = 2.68 PECIFIC FORCE (KLB) = 0.46 LOW FROUDE NUMBER = 0.00 NOTE: FROUDE NUMBER=O MEANS FLOWING FULL. * CRITICAL FLOW CONDITIONS : LOW CENTRAL ANGLE (DEGREE) = 256.310 LOW DEPTH (FEET) = 1.64 LOW AREA (SO FEET) = 2.78 LOW VELOCITY (FPS) = 7.51 INIMUM SPECIFIC ENERGY (FT) = 2.51 INIMUM SPECIFIC FORCE (KLB) = 0.45 LOPE (FT/FT) = 0.0082 Engineering Consultants 209 S. Meldrum Fort Collins, Colorado 80521 303/482-5922 FAX: 303/482-6368 DESCRIPTION: (Lot 2) A drainage easement being a portion of Lot 2 of Oakridge Business Park, Seventeenth Filing on file at the Larimer County Clerk and Recorder, Larimer County, Colorado being more particularly described as follows: Beginning at the Southeast corner of said Lot 2; thence along the South line of said Lot 2, South 90000/00/1 West, 25:82 feet; thence departing said South line, North 14030/38/1 East, 235.28 feet to a point on the North line of said Lot 2; thence along said North line, North 89038'33" East, 25.87 feet to the Northeast corner of said Lot 2; thence along the East line of said Lot 2, South 14030/38/1 West, 235.45 feet to the Point of Beginning. The, above described drainage easement contains 0.135 acres and is subject to all easements and rights -of -way now on record or existing. 348-003.06 April 26, 1995 Denver3031458-5526 RMINC. Engineering Consultants 209 S. Meldrum Fort Collins, Colorado 80521 303/482-5922 FAX: 303/482.6368 DESCRIPTION: (Lot 4) A drainage easement being a portion of Lot 4 of Oakridge Business Park, Seventeenth Filing on file at the Larimer County Clerk and Recorder, Larimer County, Colorado being more particularly described as -follows: Beginning at the Southeast corner of said Lot 4; thence along the South line of said Lot 4, South 89038/33/1 West, 56.90 feet; thence departing said South line, North 43042'31" East, 61.49 feet; thence, North 14030'38" East, 146.43 feet to a point on the North line of said Lot 4; thence along said North line, North 90000'00" East, 25.82 feet to the Northeast corner of said Lot 4; thence along the East line of said Lot 4, South 14030/38/1 West, 191.98 to the Point of Beginning. The above described drainage easement contains 0.126 acres and is subject to all easements and rights -of -way now on record or existing. 348-003.05 April 26, 1995 Denver3031458-5526