The Rationality Evaluation On The Design Of Emergency Escape Ramp Of Mountain Expressway

Emergency escape ramp have been setted on many mountain highways to improve thetraffic safety condition of continuous long downslope section. But because our research on theemergency escape ramp has just started, there has little related standard and design guide, inaddition, existing emergency escape ramps have many improper operation, which wouldaffect emergency escape ramp’s application effect seriously.Through ensuring the relation on the brake drum’s failing temperature and the distancebetween the emergency escape ramp and the top of long downslope section, according to“temperature synthesis”, terrain conditions and the road alignment conditions, the essay studyon the emergency escape ramp’s position, number and the spacing, and their evaluationstandard; according to the heavy-duty trucks’ force analysis, the essay proposed someReasonable proposal value of efflux angle; according to analysing the approach road’svertical acceleration, vertical curve visual range and the vehicle’s shortest stroke, the essayproposed vertical curve’s minimum length and minimum radius; combine with the brakelane’s slope, resistance coefficient and it’s length, the essay proposed the maximum slope toguarantee the truck not to side overturned or sideslip, and then make the correspondingevaluation standard; the essay also proposed the evaluation standard of appropriate trafficsigns, lubber, guardrail, drainage facilities and maintenance.According to emergency escape ramp’s Setting principle and Influence factor, the essaystudy on related parameters of the emergency escape ramp, such as position, number, spacing,efflux angle, arrester’s length, alignment, material, drainage, traffic safety facilities andservice facilities, and put forward the feasible evaluation method and evaluation standard. Theresearch result is the support for future design and evaluation, and it also have some referencevalue to formulate emergency escape ramp’s standard.