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116 <br /> Appendix 131 : Urban Streets — Arterials and Collectors/Locals <br /> (also used for On-Ramps and Off Ramps, not normally associated in systems planning) <br /> Exhibit 2: Adjustment Factors for Urban Streets <br /> Factor Formula Definitions of Variables Defaults/Notes <br /> Lane width fw=1 +[(W—12)/30] W=lane width Assume 1.0 <br /> Exhibit 10-12 <br /> Heavy vehicles fHv=100/[100+%HV(Er-1)] %HV=%heavy vehicles for lane Er=2.0 pc/HV <br /> group volume <br /> Exhibit 10-12 <br /> Approach grade fg= 1 —[%G/200] %G=%grade on lane group 0%-flat <br /> approach 3%-moderate grades <br /> p. 10-25 <br /> Parking fp=[N-0.1-(181\10600)]/N N=#through lanes in lane group fp >_ 0.050 <br /> Nm=#parking maneuvers/hour fp =1.00 for no parking <br /> See Exhibit 10-20 for Nm <br /> Bus blockage fbb=[N—14.4NB/3600)]/N NB= #buses stopping/hour fbb >_ 0.050 <br /> See Exhibit 10-21 for Ns <br /> Area type fa=0.900 in CBD <br /> fa= 1.00 in all other areas <br /> Lane utilization fLU=vd(vg1N) vg=unadjusted demand flow rate for Assume 1.00 for exclusive <br /> the lane group,veh/h left turn <br /> vg1 =unadjusted demand flow rate on <br /> the single lane in the lane group See Exhibit 10-23 for other <br /> with the highest volume default values <br /> N=number of lanes in the lane group <br /> Left turns Protected phasing Per=proportion of left turns in lane <br /> Exclusive lane: group See Exhibit C16-1, <br /> fir=0.95 Appendix C,for nonprotected <br /> Shared lane: phasing alternatives, <br /> fir= 1/[1.0+0.05PLr] p. 16-122 <br /> Right turns Exclusive lane: PRr=proportion of right turns in lane Assume 0.985 <br /> fRr= 0.85 group (Unless exclusive right turn <br /> Shared lane: lane is provided) <br /> fRr=1.0—(0.15)PRr <br /> Single lane: <br /> fRr=1.0—(0.135)PRr <br /> Pedestrian-bicycle FLpb=1.0-PLT(1-Apbr)(1-PLTn) PLT=proportion of left turns in lane Assume 1.00 <br /> (Left turns) group <br /> Apbr=permitted phase adjustment <br /> PLTn=ratio of left turn protected green Refer to Appendix D for <br /> to total left turn green detailed procedure <br /> Pedestrian-bicycle FRpb=1.0-PRr(1-Apbr)(1-PRTn) PRr=proportion of right turns in lane Assume 1.00 <br /> (Right turns) group <br /> Apbr=permitted phase adjustment <br /> PRrn=ratio of right turns protected Refer to Appendix D for <br /> green to total right turns green detailed procedure <br /> Figure adapted from HCM 2000 Exhibit 16-7 <br /> D-2 <br />