# LAB2 - Highway Capacity Manual 2000 EXAMPLE PROBLEM 1(PART...

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Highway Capacity Manual 2000 Chapter 21 - Multilane Highways 21-16 Example Problems EXAMPLE PROBLEM 1 (PART I) The Highway A 3.25-mi undivided four-lane highway on level terrain. A 3,200-ft segment with 2.5 percent grade also is included in the study. The Question What are the peak-hour LOS, speed, and density for the level terrain portion of the highway? The Facts Level terrain, 46.0-mi/h field-measured FFS, 11-ft lane width, 1,900-veh/h peak-hour volume, 13 percent trucks and buses, 2 percent RVs, and 0.90 PHF. Outline of Solution All input parameters are known. Demand will be computed in terms of pc/h/ln, and the LOS determined from the speed-flow diagram. An estimate of passenger-car speed is determined from the graph, and a value of density is calculated using speed and flow rate. Steps 1. Find f HV ( use Exhibit 21-8 and Equation 21-4 ). f HV = 1 1 + P T (E T – 1) + P R (E R – 1) f HV = 1 1 + 0.13(1.5 – 1) + 0.02(1.2 – 1) f HV = 0.935 2. Find v p ( use Equation 21-3 ). v p = V PHF * N * f HV * f p v p = 1,900 0.90 * 2 * 0.935 *1.00 v p = 1,129 pc/h/ln 3. Determine LOS ( use Exhibit 21-3 ). LOS C The Results LOS C, Speed = 46.0 mi/h, and Density = 24.5 pc/mi/ln.

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Highway Capacity Manual 2000 21-17 Chapter 21 - Multilane Highways Example Problems Example Problem 1 (Part I) 1 1 + P T (E T – 1) + P R (E R – 1) V or DDHV PHF * N * f HV * f p V or DDHV PHF * N * f HV * f p V or DDHV PHF * N * f HV * f p Analyst ___________________ Highway/Direction of Travel ________________ Agency or Company ___________________ From/To ________________ Date Performed ___________________ Jurisdiction ________________ Analysis Time Period ___________________ Analysis Year ________________ qq q q Operational (LOS) Design (N) Design (v p ) Planning (LOS) Planning (N) Planning (v p ) Volume, V ___________________veh/h Peak-hour factor, PHF _______________ Annual avg. daily traffic, AADT ___________________veh/day % Trucks and buses, P T _______________ Peak-hour proportion of AADT, K ___________________ % RVs, P R _______________ Peak-hour direction proportion, D ___________________ General terrain DDHV = AADT * K * D ___________________veh/h q Level q Rolling q Mountainous Driver type Grade: Length _______mi Up/Down ________% q Commuter/Weekday q Recreational/Weekend Number of lanes _______________ General Information Site Information Speed Inputs Calculate Speed Adjustments and FFS Operational, Planning (LOS); Design, Planning (v p ) Design, Planning (N) Glossary Factor Location Lane width, LW ___________________ft Total lateral clearance, TLC ___________________ft Access points, A ___________________A/mi Median type, M q Undivided q Divided FFS (measured) ___________________mi/h Base free-flow speed, BFFS ___________________mi/h f LW ____________mi/h f LC ____________mi/h f A ____________mi/h f M ____________mi/h FFS = BFFS – f LW – f LC – f A – f M ____________mi/h Application Input Output Operational (LOS) FFS, N, v p LOS, S, D Design (N) FFS, LOS, v p N, S, D Design (v p ) FFS, LOS, N v p , S, D Planning (LOS) FFS, N, AADT LOS, S, D Planning (N) FFS, LOS, AADT N, S, D Planning (v p ) FFS, LOS, N v p , S, D Operational (LOS) or Planning (LOS) Design (N) or Planning (N) 1st Iteration v p = ___________________pc/h/ln N _______________assumed S ___________________mi/h v p = _______________pc/h/ln D = v p /S ___________________pc/mi/ln LOS _______________ LOS ___________________ Design (v p ) or Planning (v p ) Design (N) or Planning (N) 2nd Iteration LOS ___________________ N _______________assumed v p ___________________pc/h/ln v p = _______________pc/h/ln V = v p * PHF * N * f HV * f p ___________________veh/h LOS _______________ S ___________________mi/h S _______________mi/h D = v p /S ___________________pc/mi/ln D = v p /S _______________pc/mi/ln f p ___________________ E R ____________________ E T ___________________ f HV = _______________ MULTILANE HIGHWAYS WORKSHEET E T - Exhibit 21-8, 21-9, 21-11 E R - Exhibit 21-8, 21-10 f p - Page 21-11 LOS, S, FFS, v p - Exhibit 21-2, 21-3 N - Number of lanes V - Hourly volume v p - Flow rate LOS - Level of service DDHV - Directional design-hour volume
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LAB2 - Highway Capacity Manual 2000 EXAMPLE PROBLEM 1(PART...

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