trip generation survey and origin / destination study

Origin Destination Surveys OD调查…and Trip Generation Surveys…交通出行率调查

TDA

Project Description

项目概况

Project Setting

项目区域现状

Travel Demand Analysis

交通需求分析

Transportation Impact Analysis

交通影响分析

Transportation Mitigation Measures 交通改善措施

Appendix A, Appendix B, etc. etc. 附录 A, 附录 B, 等等

TIA contents

But first…但首先，Traffic Counts, REVISITED…高峰时段交叉口交通流量调查,回访

TDA

Scoping Site in Advance for Intersection Traffic Counts计算前的准备工作 Visit the project site

take pictures of traffic controls and lanes 拍摄交通控制和路面情况

observe intersection conditions Minimize Complications in taking traffic counts

Engineer should make determination of staff needs, in advance.

Timing of intervals, Recording Complications means LOST DATA and a bad

count on the day of survey. Incorrect Counts Missing Information. Wrong North Arrow, etc

Traffic Count Sheet: Hard to Interpret 交通流量调查问卷 : 用中文很难解释

Problem:Intersection mis-labeled because road closure was at LongShouLu

Traffic Count Sheet: Incorrect Method 交通流量调查问卷 : 错误的方法

Counted first...5:30-5:45 pm

Counted second...5:45-6:00 pm

Counted third...6:00-6:15 pm

Traffic Count Sheet: Hard to Interpret 交通流量调查问卷 : 用中文很难解释

Traffic Count Sheet: Only 15 Minute Count 交通流量调查问卷 : 只有 15 分钟的流量调查

15 Minute Count is Not Enough 15 分钟流量调查不够

Left Out

Right Out

Left In

Right In

3:30 12 8 16 12

3:45 20 16 24 28

4:00 20 4 8 24

4:15 32 28 12 24

4:30 32 8 20 48

4:45 16 16 24 52

5:00 28 12 32 64

5:15 32 20 32 88

5:30 40 24 28 92

5:45 16 12 72 104

6:00 40 12 60 116

6:15 32 8 20 60

What you get when you multiply a 15 minute count by 4:

DIFFERENT RESULTS! 不同的结果

32 17 48 10032 17 48 10032 17 48 10032 17 48 10032 17 48 10032 17 48 10032 17 48 10032 17 48 10032 17 48 10032 17 48 10032 17 48 100

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15 Minute Count is Not Enough 15 分钟流量调查不够

Long Hu Xi Juan 3 hr. Count. 龙湖西苑 3 小时流量调查 A real count.

What happens when you multiply a 15 minute count by 4 to “short-cut” the count process. 4 当你计算 15 分钟的流量，会发生什么？ You get vastly different hourly totals! 你会得到不同的结果 Likely Incorrect. 很有可能是不正确的

3:30 3:45 4:00 4:15 4:30 4:45 5:00 5:15 5:30 5:45 6:00 6:15 Actual0

20

40

60

80

100

120

140

Left Out

Right Out

Left In

Right In

Actual Peak Hour Total 实际高峰时段总

Actual Peak Hour Total 实际高峰时段总Actual Peak Hour Total 实际高峰时段总

Peak

Hour

Volu

me

左出口

右出口

左入口

右入口

We need to Count for:

TWO HOURS minimum

We find the peak HOUR from these two hours of data.

It cannot be guessed… …it is incorrect to multiply a 15 minute count by four(4) to get an hourly total. 15min x 4 peak

hour

15 Minute Count is Not Enough This example shows that you get four very different answers

The first 15 minutes x 4 is 15% of actual. The second 15 minutes x 4 is 25% of actual. The third 15 minutes x 4 is 50% of actual, etc. etc. The fourth set was close, but that was LUCKY

3:30 3:45 4:00 4:15 4:30 4:45 5:00 5:15 5:30 5:45 6:00 6:15 Actual0

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Left OutRight OutLeft InRight In

Actual Peak Hour Total



Peak

Hour

Volu

me

Photo Documentation is very Important and Helpful

龙寿路 / 人兴路LongShou /

RenXing

Photo Location 1: 1龙寿路 / 人兴路

LongShou / RenXing

1


LongShou / RenXing

1


LongShou / RenXing

2


LongShou / RenXing

3


LongShou / RenXing

4

ORIGIN DESTINATION SURVEYS

An Overview of

TDA: Origin Destination Surveys

O&D and Mode Split Surveys OD& 交通方式调查 Different Methodologies.

License Plate Study (video, audio, or handwritten) Check-Point / Intercept Interviews.

Ask questions. 在街上采访 This can be at say, toll booth, or just on the street too.

Video and Analysis. Observe. 视频和分析。守 “Big Data” and Blue Tooth “ 大数据”和蓝牙 Phone Calls. Ask direct questions. 拨打电话。提问

Interpretation and Summary of Data Currently, Big Data has highest level of assumptions built into it,

because of: Limited data set comprised of cell phone users, or those that use blue

tooth. Latency of up to a minute.

License Plate Survey, VIDEOcan “zoom in” later for clarity, engineer just shoots video… easy

?

?

??

???

Can’t see all plates… this is a problem.

20 video Cameras Survey …filmed during PEAK HOUR. Got ALL plates.

License Plate Survey, AUDIORequires visual clarity, can be difficult for engineer to see…

?

??

???

Again, Can’t see many plates… Problem.

??

One Solution: Expensive.

When you want to get ALL cars, you need to put a video camera on ALL lanes, and get EVERY car.

You must use high speed camera shutter. You need an overhead bridge, or some other

way to get a clear shot You need a camera operator for EACH lane. Even with only two locations, you need 6-8

camera operators and 8 cameras total. One such study for one day cost $45k in USA,

and had only 6 locations (25 camera operators).

Another Solution: Sample.

A sample is different than a strict license plate survey. A sample gives you percentages of what direction people

are going, but it is with a RANDOM selection. Random selection can be done with watching video in

office and choosing a car. Random selection can NOT be done by picking a license

plate, because it biases depending on the lane visible to the engineer. Far lanes are difficult to see, and eliminating those from the sample creates a bias that is unknown.

Also, because the license plate method requires matching of plate data at each end, if there are too many missing plates in the sampling, this makes it less reliable. Hard to quantify if there are many entrance and exit points being surveyed.

Origin Destination let’s watch the Green Truck

人兴路 RENXING RD

VIDEO Origin & Destination SURVEYA REAL WORLD EXAMPLE:

Traffic Impact Analysis 交通影响分析

Project Description: Study Area

金开

大道

人和

大道

人兴路

黄山大道机场高速

NEW ROAD? What Will Happen?

WB Traffic from JinKai

Traffic Will SHIFT with New Road

We had to define this Traffic with an O&D Survey.1. The traffic on the bridge was counted: 16302. Percentage of bridge to Freeway counted: 55%

Video Survey Corridors

Video Camera Tripod Locations

Selected Study Intersections

TOOK NEW TRAFFIC COUNTS

Used iPhone Traffic Count Tool

Used Manual Traffic Count Sheet Method

Summary of Origin/Destination

Traffic Count Data was used with O&D Data

Sample Size (100 vehicles or more) of randomly selected vehicles that turned left to go south at Interchange/Intersection 8.

In this Survey: 55% of samples went south past 机场高速 45% turned right onto 黄山大道

Total Left Turn Vol = 1630 vph Result: 900 vehicles (55%) go south 730 vehicles go west on 黄山大道

Video Inspection Methodology In the video clips that follow, the

methodology used to sample traffic is set forth.

Video clips are “scrubbed” to watch a vehicle very quickly, to see where it came from, and to see where it went.

Origin Destination Samples“Video Scrubbing Method”

Worksheet: Random Sampling of Vehicles

WB Traffic from JinKai

PM Peak Hour is 2273 vehicles WB/SB on 金开大道 . 1630 turns to go south on 人和大道 . 643 goes west on 金开大道 .

55% of 1630 goes south on 人和大道 based on the O&D Video Survey results.

This is the control volume: 900

45% of 1630 goes west on 黄山大道

Reassign Traffic from JinKai

NB RenHe to EB JinKai SHIFT?

Existing NB RenHe Traffic

Same Method Usedfor NB Traffic: sampling

Using Sampling methodology lets the engineer multiple percentage (%) values by the TRAFFIC COUNT data to get the amount of traffic that would SHIFT.

You need a statistically valid sample size. At least 100 random samples.

Even the NB LEFT TURN traffic is expected to SHIFT

Other Emerging Technologies that can be used for O&D… BLUETOOTH

How it works Advantages:

It is time, date and location data, but needs interpretation (bus passengers, bikes, peds, etc., mixed with car’s data)

Can helps in determining paths and times Can be useful in timing studies, speed studies, O&D

Disadvantages: It is just small sampling, not a traffic count Traffic counts still need to be performed. It is ONLY counting the cell phones that have blue tooth

turned ON Demographics of local Bluetooth users is not known Interpretation of data to determine car status, ped status,

bike, or even bus status…

Bluetooth Sampling Devices can detect BTA phones, BTA computers, some cars

Bluetooth Sampling Technology grabs a unique BT ID Address, and matches them

Bluetooth Sampling Technologymatches IDs at different measuring stations, and computes travel times & speeds.

Bluetooth O&D Result Matches Can also detect the path traveled (assumed), depending on # of stations used. It’s still JUST sampling… because not everyone uses bluetooth.This kind of information is extremely helpful in setting up

a travel demand model, and calibrating it to real world conditions.

It is the trip distribution variable(s).

TRIP GENERATION SURVEYSAn Overview of

Trip Generation in USA

two thick manuals, 1500 pages,users guidebook too.

Trip Generation in USA ITE Manual has 162 landuses China Manual has 36 landuses

China manual can use more categories and data.

Trip Generation Data in China is 5 times less

than what USA is using. More data is needed. ITE Manual China Manual162 landuses 36 landuses

ITE ITE ITE CHINA

ITE ITE

ITE says:

ITE Updates Trip Gen Manual Banking Industry, for example…

ITE examined trip data for banks before and after technology opened up ATMs and now Internet Banking.

Vehicle and Ped trips to the bank have gone down significantly. Because of technology advances

Older Trip data for Banks (pre 2000) have been removed to prevent skewing of data.

Older data is discarded as our world changes. China is changing fast in many ways with vehicle

ownership UP, and large expansion of METRO lines.

ITE FORM only itemizes for TRUCKS. No PEDS. Mindset. Demographic

In China we also need to Count PEDESTRIANS and other MODES

Why would we need a Trip Generation Survey? Lacking Data

The China TG Manual does not have rates for many land use categories (such as VILLA, which is not in there)

We, TYLIN, conducted a VILLA count because LongHu Project had Villas as a part of project.

Villas have much higher vehicle trip counts than apts.

Data Not Local. From another area of China Is it applicable? You will not know until you conduct a TG

Survey to find out if there are similarities. Are Demographics different?

The Client has a New Land Use Type, or a Hybrid Maybe the China TG Manual does NOT have a hybrid but

an existing hybrid land use exists, and can be surveyed… If so, DO IT !

How to Scope a Trip Generation Survey

Define the Area to be surveyed The area should be a single land use type, such as

residential, or commercial, or institutional, etc. Identify all exit and entrance points.

Trip Purpose: Find out the MODE SPLIT (car, ped, bike, etc) Find out the Trip Purpose (traffic model purposes)

Training of Staff. Diagrams to help define specific duty. Photos to familiarize staff with area Execution coordinated by clock, overseen by

supervisor

Example Project:

礼嘉 A 区龙湖地块 (A61-68) 交通研究 We had BeiJing Trip Rates already… but What should we use for Trip Generation?

Since there is a residential apartment complex in the City of ChongQing that was also developed by Long Hu company ( 龙湖西苑 Long Hu Xi Juan), this is ideal and similar. There are also VILLAS nearby across the street Find out pedestrian traffic Find out auto traffic This can be used for Traffic Study Project

Also the 美地 MeiDi Villas development was surveyed to get a sample of northern CQ Villa trip generation.

PM Peak Person Trips / 100户数 ( 小户型 )

Source:

ITE does not have PED data

PM Peak Person Trips / 100户数 ( 中户型 )

Source:


PM Peak Person Trips / 100户数 ( 大户型 )

Source:


PM Peak AUTO Trips / 100 户数 ( 小户型 )

Source:

PM Peak AUTO Trips / 100 户数 ( 中户型 )

Source:

PM Peak AUTO Trips / 100 户数 ( 大户型 )

Source:

Example: RESIDENTIAL Landuse Area in red is a

“closed” land use area, gated, and filled with 1683 residential apartment units.

There are several locations to count outside the fence Car entry/exit Pedestrian entry/exit

1683

DU

Example: RESIDENTIAL Landuse

1

3

5

4

42

LongHuXiJuan Car Entry/Exit Ped Entry/Exit

Also conduct an O&D interview

These areas all need to be counted.

6 locations. 6 people.

Variables We Need to Know:

1

3

5 2

how many cars total (count at night, garage, and street at say, 2 am)

population parking spaces shopping internal? other amenities

internal? Knowing these

variables lets us refine our TG information, and even determine parking needs, etc.

1683

DU

Count Location Photos

1

3

54

42

COUNT PEDESTRIANS AND CARS THAT GO IN AND OUT OF THESE AUTO AND PED GATES, FOR 3 HOURS


3

254

4

1

COUNT PEDESTRIANS THAT GO UP AND DOWN THESE STAIRS INTO LONGHUXIJUAN, FOR 3 HOURS


3

1

54

42

COUNT PEDESTRIANS AND CARS THAT GO IN AND OUT OF THESE AUTO AND PED GATES, FOR 3 HOURS


3

54

42

1

COUNT PEDESTRIANS THAT GO TO AND FROM THIS SIDEWALK, FROM LONGHUXIJUAN


3

1

54

42

COUNT PEDESTRIANS THAT GO IN AND OUT OF THESE GATES FOR 3 HOURS (and how many just go “through”)

Taking the Count: Location 1

3

1

54

42

COUNT PEDESTRIANS AND CARS FOR ALL 6 MOVEMENTS ON DIAGRAM, FOR 3 HRS.Peak

hour: 5:15 pm-6:15 pm

What We Get From Count: We get the total PEDESTRIAN Traffic

that travels outside of the control area, and “impacts” the street network and sidewalks

It is unknown how much of this traffic visits the local shops and restaurants, but likely is a high source.

We get the total AUTO Traffic that travels outside of the control area, and “impacts” the street network.

What we don’t know is how many LongHuXiJuan residents who own cars, also park their cars on the local street instead of the internal garage. The streets are filled with parked cars at night. It is likely that our “true” AUTO trip generation rate is LOW in light of this.

Peds & Cars

COUNT RESULTS: Location 2

Peak hour

is 5:15-6:15 pm


Peak hour is 5:00-6:00 pm


Peak hour is 5:15-6:15 pm

Comparing New with the Old

PED

AUTO

MeiDi was higher, so we used it

MeiDi was lower, so we did not use it

LongHuXiJuan was similar, so we used it

LongHuXiJuan was similar, so we used it

Pedestrian Trip Generation Rates

Automobile Trip Generation Rates

trip generation survey and origin / destination study

Engineering