路桥外文翻译-毕业设计.doc

附录 外文资料原文及翻译 Porous Elastic Road Surface as An Ultimate Highway Noise Measure S. MEIARASHI Advanced Material Team, Material & Geotechnical Research Group, Public Works Research Institute, Japan meipwri.go.jp Abstract:Highway traffic noise in urban areas of Japan is a serious problem, not only for residents along highways, but also for highway administrators. Only 13 percent of urban highways have met the environment standard for noise. Noise barriers cannot be used as a noise countermeasure on the majority of highways on which access is not controlled. Noise levels of areas along some urban highways exceed the standard by 15 dB(A) or more. This problem is impeding new highway construction in urban areas. Porous asphalt pavement has recently been introduced on urban highways in Japan. Its noise reduction effect of 3 dB(A) is insufficient, because it only improves the noise environment satisfaction rate by a few percent. Furthermore, the durability of its noise reduction effect usually seems to be only three years, which is shorter than its life-cycle as pavement.The Public Works Research Institute (PWRI) has, since 1993, been developing a new low-noise pavement named “Porous Elastic Road Surface” (PERS). This new pavement has a porous structure composed of granulate rubber made from old used tires as its aggregate and urethane resin as its binder. Its porosity is approximately 40 percent. The pavement was first proposed in Sweden in the 1970s, however, Swedish researchers have failed to improve it as a practical pavement. Noise reduction levels are 15 dB(A) for cars and 8 dB(A) for trucks. The author estimates that the potential noise reduction levels in Leq exceed 10 dB(A). More than 90 percent of highways in urban areas would meet the standard if this noise reduction level were achieved. The PWRI has already solved several of the problems with PERS, for example, insufficient adhesion between the pavement and the base course, low skid resistance, and its poor fireproof performance. Its technical level has already reached the stage of test construction on urban highways.This paper examines the general performance of PERS obtained through past development at the PWRI. It also summarizes the results of recent research done to further improve the noise reduction levels of PERS and the first test construction using PERS in Japan. The final noise reduction target for any type of vehicle is between 15-20 dB(A). The author expects that PERS will reduce highway traffic noise problems in urban areas of Japan to a minor, negligible level in the near future. Key words: pavement, noise reduction, highway traffic noise, skid resistance, durability, adhesion 1IntrodutionThe Public Works Research Institute (PWRI) has, since 1993, been developing a new low-noise pavement named “Porous Elastic Road Surface” (PERS). This new pavement has a porous structure composed of granulate rubber made from old used tires as its aggregate and urethane resin as its binder. Its porosity is approximately 40 percent. The pavement was first proposed in Sweden in the 1970s, however, Swedish researchers have failed to improve it as a practical pavement. Noise reduction levels are 15 dB(A) for cars and 8 dB(A) for trucks. The author estimates that the potential noise reduction levels in Leq exceed 10 dB(A). More than 90 percent of highways in urban areas would meet the standard if this noise reduction level were achieved. The PWRI has already solved several of the problems with PERS, for example, insufficient adhesion between the pavement and the base course, low skid resistance, and its poor fireproof performance. Its technical level has already reached the stage of test construction on urban highwaysThis paper examines the general performance of PERS obtained through past development at the PWRI. It also summarizes the results of noise reduction levels of PERS at the first test construction site in Japan. The first part deals mainly with improvement of noise reduction effect with changing its porosity and thickness, adhesion to the base course, durability, wear resistance, wet friction, and fire resistance, whereas the second part focuses on the laboratory performance testing in advance to identify a new construction method of PERS before trial construction on highways and the noise reduction effect observed at the construction site 2.Latest technology 2.1 Noise reductionThe author has conducted four noise measurements in total at the PWRI testing course to improve the noise reduction effect of PERS, including the first one described above. The second noise measurement in 1995 was focused on the influence of porosity on noise reduction. Figure 2 shows that noise reduction of PERS is almost saturated at the porosity of 35% and over. In the third noise measurement of 1996, a major issue was the effect of PERS thickness on noise reduction. The optimal PERS noise reduction levels for passenger cars, light trucks, and heavy trucks are 14-16 dB(A), 4-5 dB(A), and 3-5 dB(A), respectively. Figure 3 reveals that the noise reduction of PERS becomes a maximum at the thickness of 3 cm. Considering the relatively small difference of noise reduction between 3 cm thickness of PERS and 2 cm thickness of PERS, and material cost reduction, the optimal thickness of PERS seems to exist between 2 cm and 3 cm. The optimal PERS noise reduction levels for passenger cars, light trucks, and heavy trucks are 13-19 dB(A), 8-9 dB(A), and 6-10 dB(A), respectively.trucks are 8-10 dB (A). As a result, the author had to improve wet friction while sacrificing noise reduction for passenger carsperformance than DAP, with far better deformation performance than conventional pavement such as DENAPFigure 4 - Accelerated pavement test2.5 Fire resistance Fire resistance was thought to be a potential problem, since rubber may burn fiercely. The fire hazard problem has been studied by PWRI. Squares of PERS 55 m were placed outside a laboratory, 36 liters of diesel oil or gasoline were sprinkled on the surface as well as on an adjacent (conventional) asphalt pavement. The fluid was then ignited with a torch, and factors such as pavement materials, height of flames and generation of smoke were observed and the tests were also filmed.In the experiments, three surfaces were compared: dense asphalt concrete, porous asphalt concrete and the 55 m panels of PERS. The results, as given in Table 1, show that regarding spreading speed and flame height, the PERS was safer than the dense asphalt concrete. Figure 8 illustrates these tests. Table 1 - Fire resistance test conditionSurface type Burning of fuel and pavement materials Flame height Smoke generation DenapFuel oil spreading over the pavement surface strongly burned with reddish flames but the pavement did not burn.2.5-3.0 m Fuel oil burned incompletely, producing a column of black smoke. DapFuel oil evaporating through the voids of the pavement ignited, causing blue flames. However, pavement materials did not burn.Approximately 0.3 m Only a little smoke was observed. PersFuel oil evaporating through pavement voids ignited; rubber panels burned up, causing reddish flames. Fire spread over the pavement very slowly. 1.0-1.5 m A column of black smoke was observed from the burning rubber panels. 3. First test construction PERS construction in highways requires the structure to be developed as a total pavement system and a construction method that is very different from the previous ones in PWRI test courses. There are two reasons for improving the structure and construction method.The first one is a time constraint. One potential application of PERS is for heavy-traffic arterial highways in urban areas, where the working time is limited to 10 hours at night (such as from 8 PM to 6 AM) to avoid causing traffic congestion. The standard area of pavement resurfacing of an urban highway is 2,000-3,000 square meters per day. The construction work involves removing the existing wearing course & base course, constructing new semi-flexible pavement as the base course, putting adhesive on the base course, and paving PERS as shown in Figure 9(a). Considering the working time before paving PERS, it is impossible to complete all the works within the limit.The second reason is for quality control of adhesive performance. In the early stage of development of PERS, there were various troubles concerning the adhesive as mentioned in the previous section. The polymer type of adhesive is very sensitive to the ambient conditions of curing such as temperature and humidity. It seems very difficult to maintain stable performance of the adhesive during outdoor work.In response to these problems, pre-fabricated types of PERS would appear to be the only solution. The main pre-fabricated types of pavement products are Inter-Locking Block (ILB), Pre-stressed Concrete Panel (PCP), and Reinforced Concrete Panel (RCP). The ILB has been widely used for pedestrian ways especially in prestige areas and shopping malls, where architects and planners are interested in the visual impact of paving. Some ILBs are also to be found in industrial areas, such as storage yards and dock-side paving, where the main concerns are structural performance, cost and maintenance. The PCP is pre-tensioned in the transverse direction during fabrication, and post-tensioned together in the longitudinal direction after placement. The PCP and RCP are mainly used for sections where extremely high durability is required, such as the pavement in tunnels.In view of the time constraints, it is impossible to use PCP and RCP as the base course of PERS because of the slow speed of construction of less than 100 square meters per ten hours. The present mechanical method of laying ILB improves the construction efficiency and overcomes the constraint. With this background, the author has proposed using ILB for the first test construction of PERS. However, ILB has been used in very few cases for highways and its durability for the surface course is unknown. The author has clarified the initial durability of the ILB-PERS composite surface by accelerated pavement tests in the laboratory shown in Figure 9(b). No fatal damage to the surface was found after 12,000 passes of the test truck.PERS was first constructed at Tazawa of National Highway Route 46 on 18 October, 2002. The total number of lanes is two and the width of each is 3.75 meters. The total length is 20 meters. The traffic volume, heavy traffic ratio, and speed limit are 10,120 vehicles per day, 20%, and 60k m/h, respectively. Figure 10 shows the general view of the section and the initial condition of the PERS surface. The author measured the noise of individual vehicles by using a special method proposed by Meiarashi (1996). The vehicles were limited to smaller ones such as passenger cars and light trucks, because of the short section length. Figure 11 illustrates the arrangement of equipment, including a sound level meter as a microphone and two sets of photo-detectors as a speed meter. Figure 12 shows the A-weighted peak levels of vehicles measured at PERS and DENAP. When noise reduction levels are defined as the difference in levels between PERS and DENAP, they are approximately given by the formula:PWL = 0.1V4. ConclusionThe Public Works Research Institute (PWRI) has, since 1993, been developing a new low-noise pavement named “Porous Elastic Road Surface” (PERS). The author estimates that the potential noise reduction levels in Leq exceed 10 dB(A). The PWRI has already solved several of the problems with PERS such as insufficient adhesion between the pavement and the base course, low skid resistance, and poor fireproof performance. Based on the above research results, PERS was first constructed at the National Highway Route 46. Noise reduction levels measured in the field were less than expected, because the size of the construction area was very small. The author will continue these investigations in the field and will attempt another test construction using a more efficient construction method than ILB. References:1Alan Lilley (1988): “Precast Concrete Paving History, Design, Applications and Problems”, The Journal of the Institute of Highways and Transportation, pp. 18-252 David Merritt, B. Frank McCullough, and Ned H. Burns (2001): “Feasibility of Using Precast Concrete Panels to Expedite Construction of Portland Cement Concrete Pavements”, Transportation Research Record 1761, Paper No. 01-29043Meiarashi S, et al. (1996): “Noise Reduction Characteristics of Porous Elastic Road Surface”, Applied Acoustics, Vol. 47, No. 3, pp. 239-2504Ulf Sandberg and Jerzy A. Ejsmont (2002): “Tire/Road Noise Reference Book”, INFORMEX Ejsmont & Sandberg Handelsbolag 多孔弹性路面将作为最终的高速公路隔音措施Porous Elastic Road Surface as An Ultimate Highway Noise Measure S. MEIARASHI先进的材料队，材料及岩土工程研究组，公共工程研究所，日本meipwri.go.jp摘要：在日本的市区公路交通噪音是一个严重的问题，不仅对公路沿线的居民，也对公路管理员。只有13 的城市公路已达到环境噪声标准。隔音板不能作为大多数出入不受控制的高速公路的隔音措施。一些城市的公路沿线地区的噪音水平超过15分贝（A）或以上的标准。这个问题是阻碍新的公路在城市地区的建设。多孔沥青路面最近已在日本的城市公路上采用。其噪音减少3分贝（A）的效果是不够的，因为它仅仅提高了噪声环境满意率几个百分点。此外，其降噪效果的耐久性通常差不多只有三年，这比其作为路面生命周期较短。公共工程研究所（PWRI ） ，自1993年以来，一直在开发一个新的名为“多孔弹性路面”（PERS）的低噪音路面。这种新的路面具有多孔结构，由旧轮胎制成的剂橡胶颗粒作为其骨料与聚氨酯树脂作为其粘结组成，其孔隙率约为40 。这种路面设计在20世纪70年代在瑞典首次提出的，但是，瑞典的研究人员想改善它作为一种实用的路面的想法已经失败。降低汽车噪音水平15分贝（A）和卡车8分贝（A）。笔者估计， Leq值减少潜在的噪音水平超过10分贝（A） 。如果达到这个降噪水平那么超过90 的市区公路将符合标准。公共工程研究所通过多孔弹性路面已解决了几个问题，例如，路面和基层之间的附着力不足，防滑性低，防火性能差。其技术水平已达到城市公路建设的试验阶段。本文通过过去研究所的发展中检查到多孔弹性路面的一般表现。它还概述了最近进行的研究结果，以进一步提高多孔弹性路面的降噪水平，用于多孔弹性路面的测试建筑在日本第一次建成。任何类型的车辆的最终噪声减排目标是15-20分贝（A ）之间。笔者预计，多孔弹性路面可将日本的市区公路交通噪音问题减少到很小，甚至在不久的将来可以忽略不计的水平。关键词：路面，降噪，公路交通噪声，防滑性，耐久性，粘附1引言公共工程研究所（PWRI ） ，自1993年以来，一直在开发一个新的名为“多孔弹性路面”（PERS）的低噪音路面。这种新的路面具有多孔结构，由旧轮胎制成的剂橡胶颗粒作为其骨料与聚氨酯树脂作为其粘结组成，其孔隙率约为40 。这种路面设计在20世纪70年代在瑞典首次提出的，但是，瑞典的研究人员想改善它作为一种实用的路面的想法已经失败。降低汽车噪音水平15分贝（A）和卡车8分贝（A）。笔者估计， Leq值减少潜在的噪音水平超过10分贝（A） 。如果达到这个降噪水平那么超过90 的市区公路将符合标准。公共工程研究所通过多孔弹性路面已解决了几个问题，例如，路面和基层之间的附着力不足，防滑性低，防火性能差。其技术水平已达到城市公路建设的试验阶段。本文通过过去研究所的发展中检查到多孔弹性路面的一般表现。它还概述了最近进行的研究结果，以进一步提高多孔弹性路面的降噪水平。第一部分主要涉及降噪效果的改善，改变它的孔隙率和厚度，路面和基层之间的附着力，耐久性，耐磨性，湿摩擦和耐火，而第二部分重点是通过实验室的性能测试提前确定一个关于PRES的新的施工方法，并在施工现场观察到降噪效果。2最新技术2.1 降噪笔者在研究所的测试过程中共进行了4个噪声测量，以改善多孔弹性路面的降噪效果，包括上文所述的第一个。在1995年第二次噪音测量集中于多孔性的影响对噪声降低。图2 ，显示了多孔弹性路面减少噪音在孔隙率为35及以上时几乎饱和。在1996年第三次噪声测量中，主要问题是多孔弹性路面厚度对降噪效果的影响。多孔弹性路面对客车，轻型卡车和重型卡车最佳降噪声水平分别是14-16分贝（A） ， 4-5分贝（A ） ，和3-5分贝（A）。图3表明，多孔弹性路面降噪成效最大为路面厚度是3厘米。考虑到在PERS的3 cm厚度和PERS的2 cm厚度的之间对噪声降低相对小差异和物质成本降低而论， PERS的优选的厚度似乎在2 cm和3 cm之间。客车，轻型卡车和重型卡车的最佳降噪声水平分别是13-19分贝（A） ， 8-9分贝（A） ，和6-10分贝（A）。卡车是8-10分贝（A） 。因此，笔者不得不牺牲客车降噪的同时，提高湿摩擦。性能优于DAP的,远比传统的路面变形性能更好的DENAP等 。图4 - 加速路面试验2.5耐火耐火被认为是一个潜在的问题，因为橡胶可能会猛烈燃烧。火灾隐患问题已经由PWRI研究所研究。把一个5 5米的正方形，放在实验室外， 36升柴油或汽油被洒在表面上，以及相邻（常规）的沥青路面上。然后用火炬点燃，观察因素，如路面材料