Pavement Friction V. Initial Velocity of Vehicle in Chain Accidents on Highways

The objective of this study is to determine the influence of pavement friction on the initial velocity of the first vehicle in a chain accident on highways involving three vehicles. Regression analysis on the results of these variables was conducted. Excellent correlation coefficient was found for the relationship at α = 0.05 significance level. The influence of Pavement Friction on the Initial Velocity is shown by a quadratic equation (Initial velocity = -0.075 Pavement Friction 2 -1.3359 Pavement Friction + 116.23) with R = 0.99. I. INTRODUCTION Accident reconstructing engineering is the planning, surveying, measuring, investigating, analyzing, and report making process on the intricate engineering details of how accidents occurred. The analysis and conclusions are based on the extensive application of fundamental principles of physics and engineering including Newton's Laws of Motion (1) and First Law of Thermodynamics (2). The first law of thermodynamics when applied to accidents states that the total energy before and after the accident will be the same. The input variables include roadway, vehicle, driver and environmental conditions. Accident reconstruction engineering studies can be utilized by the industry, city and state governments for modifying the structural facilities such as roads. The modifications may include obtaining improved friction factors, increased number of lanes and lane widths and better site distances. Vehicle manufacturers use the results of the studies for developing better designs of vehicles. Some of the recent vehicles may use event data recorder containing information on the speed of the vehicle before and at the time of the accident. Some manufacturers, such as GM and Ford, allow downloading the information from these boxes after an accident (3). The results of the accident reconstruction studies are also used for producing better navigations aids to assist the drivers. In this study the guidelines of Accreditation Commission for Traffic Accident Reconstruction (ACTAR) (4) are used. There are many research studies on the application of accident reconstruction engineering principles. One of the most important one is that of Hurt's (5). Hurt found that motorcyclists needed to develop their capabilities on controlling skids and proper use of helmets significantly reduced head injuries. Hurt further found that out of all the turning movements, the left turners were the most involved ones in the accidents while turning in front of the oncoming motorcycles.