Procedure for a Temperature-Traffic Model onRubberized Asphalt Layers for Roads and Railways

• 作者: Fernando Martinez Soto Gaetano Di Mino
• 来源期刊: 交通与运输工程：英文版
• 学科: 交通运输
• 关键词: Superpave rubber-modified asphalt bituminous mixtures temperature compaction sub-ballast railway indirect tensilestrength trackbed design.
• 年，卷（期）: 2017,（4）
• 页码范围: 171-202
• 页数: 32页
• 分类号: U

摘要

The impact of temperature on the mechanical properties and thermal susceptibility of the railway bituminous sub-ballastlayer, has served as motivation to develop the advanced measurement of thermal cycles in this layer and, an evaluation of the averageseasonal temperatures interpolated by sinusoidal functions, of which characteristic parameters are determined. According to weathersituation, Barber＇s temperature model was used to prove the effectiveness for the railway superstructure. It is included the assessmentof improved modified asphalt mixes performed with coarse rubber from scrap tires, having 1.5 to 3 percent of crumb rubber （particlesize 0.2-4 mm） by weight of the total mix, as sub-ballast layer in railway and base layers on roads, recurring to the Superpave mixdesign compaction enhanced after computer simulations to evaluate real stresses derived from the rail traffic and climatic conditions.This article following the assessment of the average seasonal temperatures, involves the characterization of rubberized materials withattention to crumb rubber properties, designed with dry technology, to enhance the bitumen-rubber and binder-voids ratios. Indirecttensile strength and water sensitivity tests were applied for the evaluation of its mechanical properties including dynamic complexmodulus at elevated temperature to measure the amount of bitumen absorbed by the rubber. The rubberized mix-results obtained andthe comparison with a conventional HMA （hot mix asphalt） show that these dry rubber bituminous mixtures are particularly effective indamping vibrations. The purpose of using rubber modifiers in hot mix asphalt to obtain a stiffer-elastic sustainable material has beenachieved for the assessment of its behavior in sub-ballast/base layers.