ogit Model 110% 90% 85 percentile 80% 60% 50 percentile 50% d 40% 20% 15 percentile 0% Gaps(sec)
Logit Model 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 110% 0 1 2 3 4 5 6 7 8 9 10 11 12 13 Gaps (sec) Cumulative Probability 50 percentile 85 percentile 15 percentile
Vehicle characteristics Design vehicle(标准车)-- as base for roadway design Kinetic feature -- acceleration performance Braking performance -- braking distance b 254(F±G) Stopping sight distance(SSD停车视距) 2 d=0.278s.t+ 254(F±G)
Vehicle Characteristics • Design vehicle （标准车）--- as base for roadway design • Kinetic feature --- acceleration performance • Braking performance --- braking distance • Stopping sight distance (SSD 停车视距) --- 254( ) 2 2 F G S S d i f b − = 254( ) 0.278 2 2 F G S S d S t i f i − = +
Climbing capability(爬坡能力)--bi difference between passenger car and truck when upgrade is steep; climbing lane(爬坡车 道) is suggested
• Climbing capability （爬坡能力）--- big difference between passenger car and truck when upgrade is steep; climbing lane （爬坡车 道） is suggested
Geometric Characteristics of Roadways Horizontal alignment--(平曲线) ertical alignment--(竖曲线) Cross section--(横断面)
Geometric Characteristics of Roadways • Horizontal alignment --- （平曲线） • Vertical alignment --- （竖曲线） • Cross section --- （横断面）
Traffic control devices Objective -(1) communicate with road users in a manner that information delivered to users has a high level of expectance and comfort(2) consistent in providing standardization of sign, markings and signal for drivers to avoid confusing
Traffic Control Devices • Objective --- (1) communicate with road users in a manner that information delivered to users has a high level of expectance and comfort (2) consistent in providing standardization of sign, markings and signal for drivers to avoid confusing