@phdthesis{oai:sucra.repo.nii.ac.jp:00019060,
 author = {RAHMAN, MURSHEDA},
 month = {},
 note = {117 p., The primary and main function of a residential street is to provide spaces where the inhabitants’ can perform a variety of social activities and to provide a direct access to the adjacent buildings or facilities for pedestrian and bicyclists. Therefore, residential streets should be well designed so that the local residents can live and work there now as well as in future also. However, residential streets are now becoming unsafe for the community people because of excessive vehicle speeds. In general, pedestrians and cyclists often have to share the roadways of residential areas with motorized vehicles, putting them at high risk for accidents due to excessive speed. To cope up with the speeding issues in residential streets, along with enforcement measures (30km/h speed limit), engineering measures such as speed hump have also been used to deal with excessive speeds nowadays.
However, some uncertainties were observed regarding the speed reduction caused by the installed hump. This present dissertation was therefore designed to explore the speeding mechanism on residential streets having 30 km/h speed limit with the presence of a single speed hump along the road by considering the combined effect of street environment or street features and hump. Specifically this research focuses on several purposes like (i) to identify the external factors (based on road geometry) affecting the effectiveness of speed hump; (ii) to investigate the external geometric and non-geometric factors associated with the speed reduction in the upstream of humps; (iii) to identify the suitable position of a single hump to maintain a lower speed along the entire length of the road; and (iv) to predict individual vehicle speed profile of a residential neighborhood where a hump will be installed.
The present dissertation established a relationship between road features and vehicle speed on residential street where a single speed hump is present and the roads having 30 km/h speed limit by developing numerous operating speed models at different locations along the road. Continuous profile-speed data were collected for individual vehicles by using STALKER ATS radar gun from different residential streets in Japan. To investigate the instability of speed reduction caused by the hump as mentioned earlier; this study firstly developed a speed model using multiple linear regression analysis by taking into account the speed at hump location i.e. hump speed as dependent variable. The result shows that, study street length, presence of intersection and crossing etc. are positively associated with hump speed whereas shape of hump is associated negatively. However, the maximum length of the roads selected for this part of the current research was around 200m which is very small. The speeding behavior might be changed in case of longer road section.
In practical, urban planner should require to understand comprehensively the speed reduction mechanism of a single speed hump in case of a longer road section. Therefore to understand the speed reduction characteristics in a longer road section i.e. 200m to 300m; the present study further developed several speed models at every 10m distance interval in the upstream of humps to investigate the external geometric and non-geometric factors, associated with speed reduction. A total of 500 speed data were collected from 7 different residential streets in Japan. Using multiple linear regression analysis, various road geometric features were found as significant predictors for speed reduction i.e., street marking, road width, two-way traffic, presence of sidewalk etc. A non-geometric factor named “street with many pedestrian” also found significant influence over car speed.
According to the previous studies a single speed hump is effective in reducing vehicle speed at hump location. However, for a safer and livable residential neighborhood, it is important to ensure safe speed throughout the road section not only at hump location. Therefore, the present study is finally established a statistical relationship between the vehicle speed at different distance in upstream as well as downstream of hump and the street features using multiple linear regression analysis. The regression results showed that road width, two-way traffic, one lane, placement of hump etc. had a significant influence on vehicle speed reduction. Furthermore, the developed models were validated with independent data sets. The desired speed trajectory of an individual vehicle of a traffic calmed street can be predicted by using the developed models which help practitioners to find out the optimum placement of a single hump.
On the basis of the above mentioned findings, it can be concluded that the relationship between vehicle speed and the roadway and roadside characteristics developed in this study provide helpful information to the practitioners to understand the speed reduction mechanism of a single hump in case of longer road section (i.e. 200m to 300m) and also help to find out the suitable position of a single hump. The outcome of this study is meaningful and the authors hope that it can be used to implement and enhance the guidelines and standards of installing hump in such kind of residential streets., Acknowledgements ........................................................................................................... v
Abstract .............................................................................................................................. vii
Table of Contents .............................................................................................................. x
List of Figures .................................................................................................................. xiii
List of Tables .................................................................................................................... xv
Chapter 1: Introduction .................................................................................................. 16
1.1 Background .................................................................................................................... 16
1.2 Research Objectives ...................................................................................................... 19
1.3 Research Contributions ................................................................................................. 19
1.4 Structure of Dissertation ................................................................................................ 20
Chapter 2: Speeding Problems on Residential Streets ............................................. 22
2.1 Introduction ................................................................................................................... 22
2.2 Speeding Problems in Residential Street ....................................................................... 23
2.3 Traffic Calming Measures ............................................................................................. 25
2.4 Speed Hump .................................................................................................................. 27
2.5 Effectiveness of Speed Hump........................................................................................ 28
2.6 Research Hypothesis ..................................................................................................... 29
Chapter 3: Hump Speed and Street Characteristics .................................................. 35
3.1 Introduction ................................................................................................................... 35
3.2 Study Objective ............................................................................................................. 37
3.3 Methodology .................................................................................................................. 37
3.4 Data Collection .............................................................................................................. 38
3.4.1 Site selection ........................................................................................................... 39
3.4.2 Street features ......................................................................................................... 39
3.4.3 Speed data measurement ........................................................................................ 41
3.4.4 Recording of video data .......................................................................................... 42
3.4.5 Data filtering ........................................................................................................... 43
3.5 Data Analysis ................................................................................................................. 45
3.5.1 Comparison of mean speed profile of three types of hump .................................... 45
3.5.2 Model development ................................................................................................ 45
3.5.3 Dependent variable ................................................................................................. 46
3.5.4 Operating speed models.......................................................................................... 47
3.6 Results and Discussions ................................................................................................ 51
3.6.1 Regression model based on basic factors ............................................................... 51
3.6.2 Regression model based on sub factors .................................................................. 53
3.7 Conclusions ................................................................................................................... 55
Chapter 4: Speed Reduction Characteristics in the Upstream of Speed Hump .. 57
4.1 Introduction ................................................................................................................... 57
4.2 Study Objective ............................................................................................................. 58
4.3 Methodology .................................................................................................................. 59
4.4 Data Collection .............................................................................................................. 59
4.4.1 Selected site characteristics .................................................................................... 60
4.4.2 Speed data collection .............................................................................................. 61
4.5 Data Analysis ................................................................................................................. 62
4.5.1 Calculation of zone of influence for the study locations ........................................ 62
4.5.2 Variation of vehicle speed with respect to the variation from hump distance ....... 63
4.5.3 Analysis of variance of vehicle speed based on study location .............................. 64
4.6 Model Development ...................................................................................................... 66
4.6.1 Dependent variable ................................................................................................. 66
4.6.2 Operating speed models.......................................................................................... 67
4.7 Results and Discussions ................................................................................................ 69
4.7.1 Regression Model at Different Distance from Hump in the Upstream .................. 69
4.8 Conclusions ................................................................................................................... 72
Chapter 5: Prediction Model and Optimum Placement of a Single Speed Hump ............................................................................................................................................. 74
5.1 Introduction ................................................................................................................... 74
5.2 Study Objective ............................................................................................................. 75
5.3 Methodology .................................................................................................................. 76
5.4 Data Collection .............................................................................................................. 76
5.4.1 Selected street section characteristics ..................................................................... 77
5.4.2 Speed data collection .............................................................................................. 78
5.5 Data Analysis ................................................................................................................. 78
5.5.1 Model Development ............................................................................................... 78
5.5.2 Dependent variable ................................................................................................. 78
5.5.3 Speed model estimation .......................................................................................... 79
5.5.4 Analysis of variance for speed model .................................................................... 84
5.6 Model Validation ........................................................................................................... 84
5.6.1 Dependent variable ................................................................................................. 85
5.6.2 Prediction model ..................................................................................................... 86
5.6.3 Validation analysis ................................................................................................. 86
5.7 Model Interpretations and Discussions.......................................................................... 88
5.7.1 Regression Models ................................................................................................. 88
5.7.2 Prediction Models ................................................................................................... 90
5.7.3 Validated Models .................................................................................................... 92
5.8 Conclusions ................................................................................................................... 93
Chapter 6: Conclusion and Recommendation............................................................ 95
6.1 Conclusions ................................................................................................................... 95
6.2 Speeding Problems in Residential Streets ..................................................................... 96
6.3 Street Features and Driving Speeds on a Traffic Calmed Street ................................... 96
6.4 Recommendations ....................................................................................................... 101
References ....................................................................................................................... 102
APPENDIX A .................................................................................................................. 107
Locations of Selected Street Sections for Profile-Speed Survey .......................... 107, 主指導教員 : 久保田尚, text, application/pdf},
 school = {埼玉大学},
 title = {Speed Mechanism in the urban residential areas with the presence of speed hump},
 year = {2019},
 yomi = {ラハマン, ムルシュダ}
}