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HomeMy WebLinkAbout02 - Design Report - Baxter Meadows - Roadway BAXTER MEADOWS ROADWAY DESIGN REPORT Prepared By Gary M. Swanson, P.E. Ryan E. Mitchell,E.I.,L.S.I. Prepared For Baxter Meadows Development 3-21-02 s .4u r > �V /8 NSON 1P. r'(71779f17, a .Ij Roadway Design Summary. The roadways designed for Phase 1 - Baxter Meadows Subdivision meet the typical sections as described in the Greater Bozeman Area Transportation Plan, Year 2001 Update except for Equestrian Lane (west of Latigo Avenue), Riata Road, Belgian Court, Clydesdale Court and Fjord Court. The roads that do not meet the design requirements or typical sections will be private streets, and the Home Owners' Association will be responsible for all maintenance, and liability. All public streets are designed to meet current design standards per Chapter 16.16, Bozeman Area Subdivision Regulations with all appropriate conditions per the Findings of Fact. The asphalt pavement thickness design and the roundabout were both designed by professional engineers. See additional information for more detail. Pavement Design Robert Peccia & Associates contracted with SK Geotechnical to perform the Pavement Design for this project. Please see Attachment# 1 for additional information. Roundabout Design and Peer Review Robert Peccia &Associates designed the roundabout at Baxter Lane and Ferguson Avenue to meet the design standards of FHWA - Roundabouts: An Informational Guide and Roundabout Design Guidelines, Modern Roundabout Interchanges, Ourston &Doctors, 1995. After the roundabout was designed, Robert Peccia & Associates contracted with Alternate Street Design, Orange Park, Florida to peer review the roundabout. See Attachment#2 for additional information. Dedicated Left/Thru Lanes at Baxter Lane and Gallatin Green Per the Traffic Impact Study, a dedicated left/thru lane needs to be provided at Baxter Lane and Gallatin Green. The dedicated left/thru lane was designed per AASHTO , A Policy on Geometric Design of Highways and Street, 2001, Chapter 9, Intersections to provide for 100 foot taper on Baxter Lane for the Left Turn Lane. Signing_and Striping All signing and striping is per the MUTCD and City of Bozeman Design Standards. Intersection and Street Lighting All lighting design will be performed by others. 2 Attachment # 1 Ge )technical December 12, 2001 Project 005256C Mr. Gary Swanson,PE(3) Robert Peccia &Associates P. O. Box 5653 Helena,Montana 59620-5653 Dear Mr. Swanson: Re: Addendum 1,Pavement Design and Recommendations, Baxter Meadows Subdivision, Bozeman,Montana The pavement design and recommendations for the Baxter Meadows Subdivision have been completed. This information will to assist Robert Peccia &Associates and the various contractors in designing and constructing the new arterial, collector, commercial and residential streets within the subdivision. Background Our firm performed the utility geotechnical evaluation for the project, and the results and recommendations were presented in a report dated October 29, 2001. In summary,a total of 37 borings were completed within three one-quarter sections of the Baxter Meadows Subdivision. The general soil ' profile was 1 to 4 feet of organic clay topsoil over lean clays underlain by alluvial gravels. Groundwater was encountered in most of the borings at depths ranging from 2 to 6 feet. The utility geotechnical report contains the boring logs and several tables more accurately describing the soil and groundwater conditions encountered on the site. Laboratory Test Results The results of the laboratory tests performed on four subgrade samples are summarized in Table 1 below: Table 1. Summary of Laboratory Tests Atterberg Limits Proctor Maximum Optimum Sample ASTM Dry Moisture Boring Depth LL PL P200 Symbol Density Content CBR ST-10 1'to 4' 36 16 81.9 CL 111.0 15.5 5.8 ST-20 P to 4' 52 28 80.6 OL 85.5 28.5 9.7 ST-28A 1'to 4' 38 17 60.9 CL 112.5 15.5 6.1 ST-34A 1'to 4' 42 19 86.1 CL 101.0 20.5 8.7 2611 Gabel Road,P.O.Box 80190,Billings,Montana 59108-0190 Phone:(406)652-3930; Fax:(406)652-3944 603 Nikles Drive,P.O.Box 5005, Bozeman,Montana 59715-5005 Phone:(406)585-341 l; Fax:(406)585-5855 1911 Meadowlark Lane,P.O.Box 3026, Butte,Montana 59702-3026 Phone:(406)494-1675; Fax:(406)494-1678 Robert Peccia&Associates December 12,2001 Project 005256C Page 2 I As can be seen above, four samples were selected for laboratory classification(Atterberg limits and sieve analysis), Proctor and California bearing ratio(CBR)tests. The classification tests indicated the three samples classified as medium plasticity lean clay and lean clay with sand. The American Society for Testing and Materials (ASTM)symbol for these soils is CL. The maximum dry densities of these samples ranged from 101.0 to 112.5 pounds per cubic foot(pcf), and the optimum moisture contents ranged from 15.5 to 20.5 percent. The CBR values for these samples ranged from 5.8 to 9.7. The organic clay(OL) from Boring ST-20 was also tested. The maximum dry density was 85.5 pcf and optimum moisture content was 28.5 percent. The CBR value for the sample was 9.7. Proposed Roadway Construction The roads in the subdivision will be developed/constructed over a period of six to eight years and during six different phases of the project. Robert Peccia &Associates has prepared numerous figures showing the locations,classifications and different phases of the development. Figure 5 summarizes the "Full Build-out" ADT traffic volumes on the various streets,which is anticipated to be completed in six to eight years. Full build-out traffic volumes do not include growth, and the characteristics of the development could change in the future. We therefore estimated the 2004 ADT on the various roads. These values were then used for the initial ADT design values,and appropriate growth factors were then applied. Our traffic analysis and assumptions are described in more detail later in this addendum. 1 Method The American Association of State Highway and Transportation Officials (AASHTO)method was used for our pavement design. We used the simplified approach for the traffic analysis. The AASHTO method was contained in "Flexible Paved Road Design" software prepared by AMOCO. This software also provides geotextile subgrade stabilization alternatives for pavement sections. A 20-year design period was selected. The annual growth rate and percent trucks changed for the various roadway classifications, and are summarized later in this report. We also assumed an initial serviceability level of 4.2, terminal serviceability level of 2.0, fair water removal, 1 to 5 percent moisture exposure and a drainage coefficient of 1.10 for the base and subbase courses. Subgrade The borings indicate most of the alignment will encounter stable subgrades where the base course can be placed directly on the compacted subgrade and eventually paved with asphalt concrete. In some areas, however, soft/wet alluvial clays will be encountered, which will not support construction equipment and these areas should be considered unstable subgrades. The extent of stable and unstable subgrades will need to be determined during construction,as described below. I Robert Peccia&Associates December 12,2001 • Project 005256C Page 3 I • Stable subgrade is an area showing less than 1 inch of deflection when proof rolled with rubber- tired equipment. • Unstable subgrade is an area showing 1 inch or more of deflection when proof rolled with rubber-tired equipment. We recommend using a loaded dump truck or blade scraper to perform the proof rolling. Table 2 below summarizes the anticipated pavement subgrade conditions at the boring. As can be seen, unstable subgrades requiring stabilization were encountered in 12 of the 37 borings. High groundwater was encountered in 10 of the 37 borings. The borings were performed in September 2001,and groundwater levels in Bozeman fluctuate. Depending on the time of construction,subgrade conditions change due to the fluctuating groundwater levels. Table 2. Anticipated Subgrade Stabilization for Pavement Subgrade High Groundwater Boring Anticipated Subgrade Below Topsoil Treat ment/Stabilization Problems ST-1 Dense Gravels No No ST-2 Medium Clays No Yes ' ST-3 Medium Clays No No ST4 Medium Clays No No ST-5 Rather Stiff Clay Fill No No ST-6 Soft Clays Yes Yes ST-7 Medium Clays No No ST-8 Rather Stiff Clays No No ST-9 Rather Soft Clays No No ST-10 Stiff Clay Fill No No ST-11 Rather Stiff Clays No No ST-12 Soft Clays Yes Yes ST-13A Soft Clays Yes Yes ST-14 Rather Stiff Clays No No ST-15 Soft Clays Yes Yes ST-16A Soft Clays Yes No ST-17 Medium Clays No No ST-18 Medium Clays No No ST-19 Soft Clays Yes Yes ST-20 Soft Clays Yes Yes ST-21 Rather Soft Clays No No ST-22A Soft Clays Yes No ST-23 Rather Soft Clays No No ST-24 Stiff Clays No No ST-25 Stiff Clays No No ST-26A Rather Stiff Clays No No ' ST-27A Soft Clays Yes Yes ST-28A Medium Clays No Yes Robert Peccia & Associates December 12,2001 Proiect 005256C Page 4 Subgrade High Groundwater Borin Anticipated Sub grade Below Topsoil Treat ment/Stabilization Problems ST-29 T Dense Gravel No Yes ST-30 Dense Gravel No No ST-31 Soft Clays Yes No ST-32 Dense Sands No No ST-33 Medium,Wet Clays Yes No ST-34A Medium,Wet Clays Yes No ST-35 Rather Stiff Clays No No ST-36A Stiff Clays No No ST-37 Stiff Clays No No Design CBR Using the CBR tests conducted on lean clay soils,the average CBR was 6.9 and the standard deviation was 1.6. Selecting a design CBR one standard deviation below the mean results in a design value of 5. Pavement Thicknesses—Stable Subgrades ' Stable subgrades will exhibit less than 1 inch of deflection when proof rolled and will likely consist of medium to stiff lean clays and medium dense to dense alluvial gravels after the organic clay topsoil has been stripped. The resulting stable subgrades should be scarified to a depth of 6 inches and recompacted to a minimum of 95 percent of its standard Proctor maximum dry density(AASHTO T99). Table 3 below summarizes our recommended pavement thicknesses for the various roadway types in the Baxter Meadows Subdivision for stable subgrades. We have also included traffic information used for the pavement design and the resulting total 18-kip equivalent single axle loads (ESALs)expected on the street. Table 3. Traffic Summary and Recommended Pavement Thicknesses(Stable Subgrades) Item ArteriaI7 Collector Commercial Residential Estimated 2004 ADT 8,000 4,000 2,000 1,000 Trucks,percent 4.0 4.0 10.0 4.0 Annual Growth Rate,percent 8.0 6.0 6.0 6.0 ESALs,total 3,078,718 1,237,408 1,546,761 309,352 Base Course Section Asphalt Surface 4" 3" 3" 3" 3/4"or 1"Base Course 16" 14" 15" 10" Subbase Section Asphalt Surface 4" 3" 3" 3" 3/4" or 1"Leveling Course 4" 4" 4" 4" 3" Subbase 16" 14" 15" 9" Robert Peccia& Associates December 12,2001 Project 005256C Page 5 Pavement Thickness - Unstable Subgrades Unstable subgrades can be identified during construction by proof rolling where 1 inch or more of deflection is occurring. In these areas, we either recommend providing subgrade treatment or stabilization as summarized below. Subgrade Treatment. Subgrade treatment basically consists of letting the existing wet clays dry out. This can likely be best accomplished by discing the top 6 to 8 inches of the subgrade, then waiting for the clays to dry out. Once dried,the subgrade should be recompacted to 95 percent of its standard Proctor maximum dry density. The advantage to this method is that it is relatively inexpensive. The disadvantage, however, is that it is time consuming. Frequent evening showers in the Bozeman area can also rewet the clays, causing them to become even more saturated. Significant additional time is then needed for them to dry. Scarifying and allowing the clay subgrades to dry can cause delays during construction. Subgrade Stabilization. Another alternative for unstable subgrades is to provide stabilization with geotextile fabric. In these areas, it is our opinion the soft/wet subgrade should not be recompacted. Instead,the pavement sections should be designed based on the subgrade strength. It is our opinion the soft/wet subgrades will have a shear strength of approximately 250 to 500 pounds per square foot(psf), resulting in a CBR value of 1.4. This is a very low value and basically represents the "worst-case" condition for the proposed streets. ' The "Flexible Paved Road Design" was used to provide pavement sections with geotextile fabric. Based on the above assumptions, we recommend providing the following pavement sections where unstable subgrades are encountered. Item Thickness Geotextile Section Asphalt Surface* 3" /4" 3/4" or 1" Leveling Course 611 3" Minus Sandy Gravel Subbase 20" Woven Geotextile Fabric Total Thickness 29" *Use 4" of asphalt surface on arterial roads. In areas where just soft subgrades are encountered, we recommend using a woven geotextile fabric equivalent to or better than AMOCO 2004. In areas where soft subgrades and groundwater within 6 inches of subgrade level are present,we recommend using woven geotextile fabric equivalent to or better than AMOCO 2016. Contech fabrics are also available in the Bozeman area. Gravel Surfacing It is our understanding some of the roads will not be paved for several months or more after the base/subbase has been placed. For these roads, we recommend substituting 3/4"-or 1%minus leveling gobert Peccia&Associates December 12,2001 Project 005256C Page 6 course for the required asphalt thickness. When ready to pave, the roads will have to be regraded to provide the recommended section. Haul Roads and Staging Areas It is our understanding that several haul roads and staging areas will be provided within the subdivision during construction. These areas will receive significant truck and construction traffic,and will likely be gravel surfaced for several years. We recommend providing the geotextile section in designated haul roads and staging areas. The geotextile will help provide subgrade stabilization in wet areas and separation of the subgrade/subbase. The geotextile fabric more evenly distributes axle loads,reducing the amount of gravel surfacing rutting. The amount of maintenance and regrading required on the gravel roads is then reduced. Subgrade Disturbance/Excavation The borings indicate the subgrade over most of the alignment will be lean clays. These clays are considered highly moisture-sensitive and are easily disturbed by heavy rubber-tired equipment such as bucket scrapers,dump trucks, concrete trucks and haul trucks. Heavy equipment traffic can make stable subgrades become unstable, which will result in additional costs and construction delays. In some areas, soft/wet lean clays were encountered which will not support heavy equipment. In these areas, light-tracked equipment such as backhoes and small bulldozers will be necessary to excavate to subgrade levels. _ Where stiffer clays are present, earthwork can likely be performed with the heavier equipment. The sensitive clays, however,may begin to lose strength under repeated heavy traffic. Eventually,the clays will become unstable and subgrade treatment/stabilization will be necessary. We therefore recommend extreme care be taken in areas where heavy construction equipment is used for earthwork. If the subgrade becomes unstable,the heavy equipment needs to be removed from the subgrade and the earthwork completed with light equipment. Good drainage of surface water is also recommended during construction. Ponding water will result in clay saturation,creating soft spots. Excessive disturbance of the soft spots occurs when driven across by construction equipment. These areas then become unstable and require treatment/stabilization. Specifications We recommend all earthwork and construction be performed in accordance with Montana Public Works Standard Specifications (MPWSS) and City of Bozeman Modifications. We recommend the subbase meet the requirement in the City of Bozeman Subdivision Standards. The subbase gravel is identified in Table 3 on Page 56,however, it refers to this material as being "pit-run." The "pit-run" description should not be used, and should be replaced with sandy gravel. For the gravel base,we recommend using Grade I or Grade 2 base course meeting the requirements of Table 4—Crushed Top Surfacing Type A. It is our opinion the base and subbase can be compacted to 95 percent of its maximum dry density determined in accordance with AASHTO Method of Test T99 (standard Proctor). The Bozeman )Robert Peccia&Ass_ociates December 12,2001 Project 005256C Page 7 Standards indicate the base and subbase should be compacted to AASHTO T180(modified Proctor). We have recommended the standard Proctor for numerous projects in the Bozeman area,and it has performed quite well. The modified Proctor requires a higher degree of compaction, which will be more difficult to achieve. For these reasons,it is our opinion the standard Proctor is suitable for support of paved roads within the subdivision. General We have appreciated the opportunity to provide these services on the project. Please refer to our original geotechnical report dated October 29,2001, for more detailed results,boring logs,analysis and recommendations. If you have any questions,please contact me at your convenience. Sincerely, Professional Certification I hereby certify that this report was prepared by me and that I am a duly Licensed Professional Engineer ruder the laws of the State of Montana. i ry T. S eno, PE ' nncipal, G chnical Engineer License 10798PE Cory G.Rice,PE Reviewing Engineer gts/cgr:khr Attachments: Figure 5 c: SK Geotechnical Corporation(Butte) • r I IDeadman's Gulch Phase IV m t O • d . n c •.g SSL:� 0 0 lG -� N o O O O u) o E • I:. k�, ase I Ph o f ;;,,ass '•,'`�;�� T;:� - .,� o it hasetrVl•��" 600 , 1,000 ..r:�•.�'�`�''- 1�{.�� Baxter Lane 6,000 10,000 g , 100 1,000 '' 00 on 0 200 cc 0 100 400 re o p o Proposed 1MAcre cc N N O Regional Park rn m .. U- Phase V 500 5,000 0 0 0 o c � o 1,300 Oak Street 13,000 200 2,000 ORecommend Left,Through/Right Turn Lanes Figure 5 200 = PM Peak Traffic Volume 12,000 =ADT Volume Traffic Volume Map Full 6uildout Attachment # 2 ■� � Alternate Street Design, P.A. 1516 Plainfield Avenue, Orange Park, Florida 32073-3925 904-269-1851, Fax 904-278-4996, Email: wallwork@mediaone.net January 31, 2002 Mr. Ryan Mitchell, E.I. Robert Peccia & Associates P.O. Box 5653 Helena, MT 59604 Re: Roundabout Design Review Dear Mr. Mitchell: I have reviewed the roundabout proposal you sent me and I recommend a few changes as follows: 1. The bike ramps have been redesigned to be more compact and to lower the speed of any bicyclist that may use the sidewalk system. By providing 45-degree ramps, rather than square and parallel ramps, bicyclists are forced to slow as the exit the bike lane and enter the sidewalk or to keep their speed lower as they accelerate to go from the sidewalk to the bike lane. 2. When applying AutoTurn to the design WB-50 trucks would travel over the curb line. Therefore the entry and exit lanes were modified to accommodate these large trucks on all movements. 3. Even though the above changes have increased the design speed slightly it is approximately 20 mph, which is within the acceptable range for this environment. 4. The crosswalks are too far back. Unfortunately the FHWA Guide recommends that the crosswalks be located 25 feet from the entry point. The 25 feet is equal to the 25 feet used in queuing analysis where the length of a vehicle is measured from the from the front of one car to the front of the next car is 25 feet. Internationally crosswalks are placed one car length back from the yield line that is typically 20 feet. The intent of the crosswalk placement at 20 feet is to allow a pedestrian to cross behind a car when it stops at the yield line, a safe time to cross. If two cars stop then there is space between them that coincides with the crosswalk so pedestrians can cross through the two cars at the safest time in which to cross. With a setback of 25 feet the second car would block the crosswalk so a pedestrian could not take advantage of the stopped vehicles to cross safely. 5. No comments could be made on signing or the markings nor the construction details of the central and splitter islands as the information was not provided. Ideally these issues should be reviewed as they can have an impact on the operation of the roundabout. 6. A SIDRA analysis showed a LOS of B including geometric and stopped delay. Sincerely, Pr Michael J. Wallwork, P.E. President Akcelik & Associates Pty Ltd - aaSIDRA 1.0.7 --------------------------------------------------- Alternate Street Design, P.A. Michael Wallwork Registered User No. a0172 Licence Type: Promotional, Multi Computer Time and Date of Analysis 10:01 AM, Jan 31,2002 Filename: C: \aaSIDRA\Data\Boise\Predicted.OUT BAXTER/FERGUSON INTERSECTION * PREDICTE PREDICTED TRAFFIC VOLUMES Intersection ID: SIDRA US Highway Capacity Manual (1997) Version RUN INFORMATION --------------- Basic Parameters: Intersection Type: Roundabout Driving on the right-hand side of the road aaSIDRA US Highway Capacity Manual (1997) Version Input data specified in US units Default Values File No. 11 Peak flow period (for performance) : 15 minutes Unit time (for volumes) : 60 minutes (Total Flow Period) Delay definition: Control delay Geometric delay included HCM Delay and Queue Models option selected Level of Service based on: Delay (HCM) Queue definition: Back of queue, 95th_Percentile BAXTER/FERGUSON INTERSECTION * PREDICTE PREDICTED TRAFFIC VOLUMES Intersection ID: Roundabout Table S.0 - TRAFFIC FLOW DATA (Flows in veh/hour as used by the program) ------------------------------------------------------------------------- Mov Left Through Right Flow Peak No. --------- --------- --------- Scale Flow LV HV LV HV LV HV Factor ------------------------------------------------------------------------ West: West Approach 12 11 1 65 1 0 0 1.00 0.90 ------------------------------------------------------------------------- East: East Approach 22 0 0 163 3 272 6 1.00 0.90 North: North Approach 42 218 4 0 0 22 1 1.00 0.90 Based on unit time = 60 minutes. Flow Scale and Peak Hour Factor effects included in flow values . BAXTER/FERGUSON INTERSECTION * PREDICTE PREDICTED TRAFFIC VOLUMES Intersection ID: Roundabout Table R.0 - ROUNDABOUT BASIC PARAMETERS Circulating/Exiting Stream Cent Circ Insc No.of No.of Av.Ent ----------------------------------- Island Width Diam. Circ. Entry Lane Flow %HV Adjust. %Exit Cap. Diam Lanes Lanes Width (veh/ Flow Incl. Constr. (ft) (ft) (ft) (ft) h) (pcu/h) Effect ---—------------------------------------------------------------------- ----- West: West Approach 64 20 104 1 1 13 .00 222 2.0 222 0 N East: East Approach 64 20 104 1 1 13.00 11 2 .0 11 0 N North: North Approach 64 20 104 1 1 13.00 167 2.0 167 0 N ------------------------------------------------------------------------ BAXTER/FERGUSON INTERSECTION * PREDICTE PREDICTED TRAFFIC VOLUMES Intersection ID: Roundabout Table R.1 - ROUNDABOUT GAP ACCEPTANCE PARAMETERS --------------------------------------------------------------------- Turn Lane Lane Circ/ Intra- Prop. Critical Follow No. Type Exit Bunch Bunched Gap Up Flow Headway Vehicles (s) Headway (pcu/h) (s) (s) ----------------------------------------------------------------------- West: West Approach Left 1 Dominant 222 2 .00 0.266 5 .03 2 .62 Thru 1 Dominant 222 2.00 0.266 5.03 2.62 ----------------------------------------------------------------------- East: East Approach Thru 1 Dominant 11 2.00 0.015 3 .60 1.81 Right 1 Dominant 11 2 .00 0.015 3 .60 1.81 ---------------------------------------------------------------------- North: North Approach Left 1 Dominant 167 2.00 0.207 4.52 2.33 Right 1 Dominant 167 2 .00 0.207 4.52 2 .33 BAXTER/FERGUSON INTERSECTION * PREDICTE PREDICTED TRAFFIC VOLUMES Intersection ID: Roundabout Table S.6 - INTERSECTION PERFORMANCE ------------------------------------------------------- Total Total Aver. Prop. Eff. Perf. Aver. Flow Delay Delay Queued Stop Index Speed (veh/h) (veh-h/h) (sec) Rate (mph) ------------------------------------------------------ West: West Approach 78 0.25 11.6 0.371 0.64 2 .15 29.7 ----------------------------------------------------- East: East Approach 444 1.11 9.0 0.060 0.60 11.43 30.8 ---------------------------------------------------------- North: North Approach 245 0.87 12.7 0.324 0.65 6.87 29.3 INTERSECTION: 767 2 .23 10.5 0.176 0.62 20 .44 30.2 -------------------------------------------------------- BAXTER/FERGUSON INTERSECTION * PREDICTE PREDICTED TRAFFIC VOLUMES Intersection ID: Roundabout Table S.12A - FUEL CONSUMPTION, EMISSIONS AND COST - TOTAL ---------------------------------------------------------------------- Mov Fuel Cost HC CO NOX CO2 Lead No. Total Total Total Total Total Total Total ga/h US$/h kg/h kg/h kg/h kg/h kg/h West: West Approach 12 LT 2 .4 20.33 0.027 1 .00 0.039 22.5 0.00000 2.4 20.33 0.027 1.00 0.039 22.5 0.00000 East: East Approach 22 TR 13 .2 112.64 0.151 5.40 0.213 125.1 0.00000 ------------------------------------------------------- 13 .2 112.64 0.151 5.40 0.213 125.1 0.00000 ------------------------------------------------------------------------- North: North Approach 42 LR 7 .6 65.41 0.088 3 .15 0.122 71.8 0.00000 7 .6 65.41 0.088 3 .15 0.122 71.8 0.00000 ----------------------------------------------------------------------- INTERSECTION: 23 .2 198.38 0.267 9.55 0.374 219.4 0.00000 Due to recent changes to lead content related to the phasing out of leaded fuel, lead values reported above may not be reliable. PARAMETERS USED IN COST CALCULATIONS ------------------------------------ Pump price of fuel (US$/ga) = 1.600 Fuel resource cost factor = 0.70 Ratio of running cost to fuel cost = 3 .0 Average income (US$/h) = 15.00 Time value factor = 0 .40 Average occupancy (persons/veh) = 1.2 Light vehicle mass (lb) = 3000 Heavy vehicle mass (lb) = 20000 BAXTER/FERGUSON INTERSECTION * PREDICTE PREDICTED TRAFFIC VOLUMES Intersection ID: Roundabout Table 5.14 - SUMMARY OF INPUT AND OUTPUT DATA -------------------------------------------------------------------- Lane Arrival Flow (veh/h) Adj . Eff Grn Deg Aver. 95% Shrt No. -------------------- %HV Basic (secs) Sat Delay Queue Lane L T R Tot Satf. 1st 2nd x (sec) (ft) (ft) --------------------------------------------------------------------- West: West Approach 1 LT 12 66 78 3 0.073 11.6 11 ------------------------- -- 12 66 0 78 3 0.073 11.6 11 --------------------------------------------------------------- East: East Approach 1 TR 166 278 444 2 0.232 9.0 38 ---------------------------------------------------------------- 0 166 278 444 2 0.232 9.0 38 -------------------------------------------------------------------------- North: North Approach 1 LR 222 23 245 2 0.186 12 .7 32 ------------------------------ 222 0 23 245 2 0.186 12 .7 32 ------------------------------------- ALL VEHICLES Tot % Max Aver. Max Ate, HV X Delay Queue 767 2 0.232 10.5 38 Total flow period = 60 minutes. Peak flow period = 15 minutes. Note: Basic Saturation Flows are not adjusted at roundabouts or sign- controlled intersections and apply only to continuous lanes. Values printed in this table are back of queue (vehicles) . BAXTER/FERGUSON INTERSECTION * PREDICTE PREDICTED TRAFFIC VOLUMES Intersection ID: Roundabout Table 5.15 - CAPACITY AND LEVEL OF SERVICE (HCM STYLE) -------------------------------------------------- Mov Mov Total Total Deg. Aver. LOS No. Typ Flow Cap. of Delay (veh (veh Satn /h) /h) (v/c) (sec) -------------------------------------------------- West: West Approach 12 LT 78 1068 0.073 11.6 B ------------------------------------ 78 1068 0.073 11.6 B -------------------------------------------------- East: East Approach 22 TR 444 1914 0.232* 9.0 A ------------------------------------ 444 1914 0.232 9.0 A -------------------------------------------------- North: North Approach 42 LR 245 1320 0.186 12.7 B -------------------------------------- 245 1320 0.186 12.7 B -------------------------------------------------- ALL VEHICLES: 767 4303 0.232 10.5 B -------------------------------------------------- INTERSECTION: 767 4303 0.232 10.5 B -------------------------------------------------- Level of Service calculations are based on average control delay including geometric delay (HCM criteria) , independent of the current delay definition used. For the criteria, refer to the "Level of Service" topic in the aaSIDRA Output Guide or the Output section of the on-line help. * Maximum v/c ratio, or critical green periods BAXTER/FERGUSON INTERSECTION * PREDICTE PREDICTED TRAFFIC VOLUMES Intersection ID: Roundabout Table D.3 - LANE QUEUES --------------------------------------------------------------------------- Deg. Ovrfl. Average (veh) Percentile (veh) Queue Lane Satn Queue ----------------- ----------------------------- Stor. No. x No Nbl Nb2 Nb 70% 85% 90% 95% 98% Ratio ----------------------------------------------------------------------------- West: West Approach 1 LT 0.073 0.0 0.1 0.0 0.1 0.3 0.3 0.4 0.4 0.5 0.00 --------------------------------------------------------------------------- East: East Approach 1 TR 0.232 0.0 0.5 0.0 0.5 0.9 1.1 1.2 1.5 1.7 0.01 ----------------------------------------------------------------------------- North: North Approach 1 LR 0.186 0.0 0.4 0.0 0.4 0.7 0.9 1.0 1.3 1.5 0.01 ----------------------------------------------------------------------------- Values printed in this table are back of queue (vehicles) . --- End of aaSIDRA Output --- 1