Effect Mechanism Research Of Highway Roadside Landscape Patterns On Driving Behavior

Previous studies have demonstrated that the appropriately landscaped highway scenes may not only help improve road safety and comfort, but also help protect ecological environment. Yet there is very little research data on landscaping design in a dynamical, objective and novel idea. Mainly because the implicit relationship between the road users and highway landscape design was seldom explored in most recent studies. The issue that the highway surrounding is not only tedious but long can pose hazards to road safety. Against this backdrop, the paper sheds new light on the effect mechanism between the highway landscaping spatial design and the driving ergonomics from the perspective of the psychological and physiological characteristics of road users. Interdisciplinary theories employed in this paper include those on traffic engineering psychology, and highway landscaping, etc. And devices utilized here are the driving simulator, and electrocardiograph. These studies are designed in the combination of the driving-simulator studies with the field operational tests for verification.The thesis falls into four key progressive parts.Firstly, classification research on the landscaping patterns. Classify the landscaping patterns based on the objective D/H index. And verify the classification’s accuracy by the subjective evaluation on one’s vision-open degree. The results show that the proposed landscaping patterns include three typical enclosure types, namely, open, semi-open and vertical ones.Secondly, driving ergonomic research under different highway landscaping patterns. Select thirty participants to participate in the simulated driving assignments featured with different landscaping patterns. The participants’ ECG data and the vehicles’ operating data are collected. And differences of implicit driving ergonomics are examined under different landscaping patterns. The results testify that significant differences exist in the open and vertical patterns. The featured indices LD and LF/HF are extracted as well.Thirdly, threshold research on highway length under different landscaping patterns. Based on the simulated driving experiment held in the long and straight highway, explore the rule behind the variation trend of the participants’ ECG index LF/HF along with the highway length. The highway-length’s models featured in cubic polynomial are established based on the rule. The critical threshold under each landscaping pattern is determined by the function’s derivative. Compared with the expected length thresholds evaluated by the subjective questionnaires, it’s indicated that the theoretical highway length thresholds in the models have precision rates higher than 90%. Thus the model results have high reliabilities.Finally, verification research on the simulated driving tests. The field operational tests are organized. The ECG evaluation indices HR and LF/HF in high precision are selected and collected. Compare the correlation and trend consistence of each index in and out of the simulator. The results demonstrate that each index collected in the simulator has strong correlation and high trend consistence with that collected in the field test. The results verify the relative effectiveness of those data collected in the simulated tests. Morover, the critical threshold under each field landscaping pattern is determined by the function of LF/HF. Compared with the theoretical length thresholds gotten from the simulator tests, it’s indicated that the highway length thresholds in the fields have high precision rates between 82%~99%. Thus the field thresholds have high reliabilities.The aforementioned findings in this thesis can essentially contribute to grasp the flexible and human-oriented concept of highway design practice, by proposing beneficial environmental countermeasures for road safety.