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13.4交织区域的分析 Weaving areas have been the subject of a great deal ofresearch since the late 1960s, yet many features of current procedures rely heavily on judgment. This is primarily due to the great difficulty in and cost of collecting comprehensive data on weaving operations. Weaving areas cover significant lengths and generally require videotaping from elevated vantage points or time-linked separate observation of entry and exit terminals and visual matching of vehicles. Further, there are a large number of variables affecting weaving operations, and,therefore, a large number of sites reflecting these variables would need to be observed.自20世纪60年代后期就对交织区域问题进行了大量的研究,然而，许多现行规程的特点主要还是依赖于判断。这主要是由于在交织运作方面的全面的数据收集存在极大的困难和成本 。交织区域主要涉及重要的交织路段长度和一般需要从较高的有利位置进行录像或进出口路端的时间分离观察及车辆匹配的视界。此外,存在大量的影响交织运作的潜在变量,并且，因此,许多的位置体现出这些变量需要能被观察到。The first research study leading up to the thirdedition 1985 HCM focused on weaving areas 3. This unfortunate, as basic section models would be revised later, causing judgmental modification in weaving models for consistency. It relied on 48 sets of data collected by the then Bureau of Public Roads in the late 1960s and an additional 12 sets collected specifically for the study. The methodology that resulted was complex and iterative. It was later modified as part of a study of all freeway-related methodologies 4 in the late 1970s. In 1980, a set of interim analysis procedures was published by TRB 5, which included the modified weaving analysis procedure. It also contained an independently developed methodology that produced often substantially different results. The latter methodology was documented in a subsequent study 6. To resolve the differences between these two methodologies, another study was conducted in the early 1980s, using a new data base consisting of 10 sites 7. This study produced yet a third methodology, substantially different from the first two. As the publication date of the 1985 HCM approached, the three methodologies were judgmentally merged, using the ten 1980s sites for general validation purposes 8. A number of studies throughout the 1980s and 1990s continued to examine the various weaving approaches, with no common consensus emerging 9-12.第一个主要集中于交织区域的研究是在1985年HCM的第三版之前3。这是不幸的,因为随后基本部分规程就被修改了，为了导致在交织规程审判的一致性。它项研究主要依靠20世纪60年代末当时的公路局的48台数据采集仪和专门为这项研究附加的十二台采集仪。这种方法导致的结果是复杂和重复的。后来的修改是作为20世纪70年代后期高速公路有关的方法的研究的一部分。在1980年,一套临时的验定规程被TRB出版了5,它包含了最新修改的交织分析规程。它也包含了一个独立开发的方法，这个方法经常产生完全不同的结果。后者的方法在后续的研究被证明6。为了解决这两种方法之间的差异,20世纪80年代初期另一项研究被实施,利用由十个站点组成的新的数据库。本研究产生了另外第三个方法,它与前两个方法完全不同。当1985年HCM的出版日期接近时,这三种方法被融合了,使用十个20世纪80年代的站点作为基本确定的目标站点8。在20世纪80年代和90年代大量的研究继续检验各种交织分析方法,一直没有共识出现(9 - 12。It was, therefore, no surprise that a new study, relying on some new data but primarily on simulation, was commissioned as part of the research for the HCM 2000 13. Unfortunately, the simulation approach was not particularly successful, and it yielded a number of trends that were judged (by the Highway Capacity and Quality of Service Committee of the Transportation Research Board) to be counterintuitive. The method of the HCM 2000, presented here, resulted from a further judgmental modification of earlier procedures 14.所以，不要对一项主要依赖于一些新数据进行计算机仿真模拟，并被委任作为HCM2000研究的一部分的新的研究而感到奇怪13。不幸的是,仿真方法不是相当成功,并产生了许多被判定为(被公路通行能力和服务委员会的服务质量和交通调查研究会)是违反直觉的趋势。这种HCM2000的研究方法，一出现，导致较早的规程进一步地被审判修改14。13.4.1 Flows in a Weaving Area13.4.1交织区的流动In a typical weaving area, there are four component flows that may exist. By definition, the two that cross each others path are called weaving flows, while those that do not are called non-weaving flows. Figure 13.3 illustrates在一个典型的交织区，有四个流动组成部分可能存在。根据定义，两个相互交叉的路径被称为交织流，而另外那些被称为非交织流。如图13.3所示。Vehicles entering on leg A and exiting on leg D cross the path of vehicles entering on leg B and exiting on leg C. These are the weaving flows. Movements A-C and B-D do not have to cross the path of any other movement, even thought they may share lanes, and are referred to as non-weaving or outer flows.从匝道A进入且从匝道D出来的车辆与从匝道B进入且从匝道C出来的车辆相互交叉.这些都是交织流。从A移动到C和从B移动到D不用以其他任何形式的移动来穿越道路，甚至认为他们可以分享车道，被称为非交织、外部流。By convention, weaving flows use the subscript w, while outer or non-weaving flows use the subscript 0. The larger of the two outer or weaving flows is given the second subscript 1, while the smaller uses the subscript 2. Thus:Vol = larger outer flow, pc/h, equivalent base conditionsvoz = smaller outer flow, pc/h, equivalent base conditionsvwl = larger weaving flow, pc/h, equivalent base conditionsvwz = smaller weaving flow, pc/h, equivalent base conditions按照惯例,交织流使用下标“w”,而外部或非交织流使用下标 0 。较大的两外部流或交织流给第二下标“1”,而较小的用下标“2”。因此: v（01）=大外部流，辆/小时，等效基本条件v（02）=小外部流, 辆/小时，等效基本条件 v（w1）=大交织流，辆/小时，等效基本条件v（w2）=小交织流，辆/小时，等效基本条件图中单词：Weaving Segment Flows 交织分割流Weaving Diagram 交织图解Figure 13.3: Flows in a Weaving Area and the Weaving Diagram 图13.3：交织区域的车辆流动和交织图解The schematic line drawing of Figure 13.3 is called the weaving diagram. In block form, it shows the weaving and non-weaving flows and their relative positions on the roadway. By convention, it is always drawn with traffic moving from left to right. It is a convenient form to illustrate the component flows in a consistentway for analysis.图13.3所示的线条示意图被称作交织图解。在整块图表中,它展示了交织及非交织流和它们在道路的相对位置。按照惯例,它总按交通流从左向右绘制。它是一种很方便的表格形式去说明合成流用一致的方法分析。Other critical variables, used in analysis algorithms, may be computed from these:Vw = total weaving flow, pc/h = Vwl + VwzVnw = total non-weaving or outer flow, pc/h = Vol + VozV = total demand flow, pc/h = Vw + VnwV R = volume ratio = Vw/vR = weaving ratio = Vwz/vw过去常常用于计算分析的其他关键变量可以用这些公式计算：w=总交织流,pc/h = wl + wznw=总非交织、外部流,pc/h =第01+02=总需求流,pc/h =w+ nwV R =体积比=w/ R =交织比= w2 /w13.4.2 Critical Geometric Variables13.4.2关键几何变量Three geometric variables have a significant effect on the quality of weaving operations: Lane configuration Length of the weaving area, ft Width (number of lanes) in the weaving areaEach of these has an impact on the amount of lanechanging that must or may occur, and the intensity of that lane-changing.三个几何因素已经显著影响到交织操作的质量:1.车道配置2.交织区域的长度,3.在交织区域的宽度（车道的数量）每一种因素都会影响到必须或是可能发生的变道的数量和变道的强度。Lane Configuration车道配置Lane configuration refers to the manner in which entry and exit legs connect. Seven different configurations have been identified, but many of these are rare, and little is known concerning their characteristics. The seven have been grouped into three major categories of configuration, each with unique features that significantly affect operations. These configurations are illustrated in Figure 13.4.车道配置涉及的方式是指进出口的连接。7种不同的配置已被证实,但这些中很多是很少见的,而且很少有关于它们特点的说明。这七种配置被分成三种主要类型的配置，各有特色,它们可显著影响操作。这些配置被说明如图13.4。Type A Configurations The most common Type A weaving configuration is often referred to as a rampweave (Figure 13.4 la). It is formed by a one-lane on-ramp followed by a one-lane off-ramp connected by a continuous auxiliary lane.The unique feature of a Type A weaving configuration is that each and every weaving vehicle must make at least one lane-change. Further, allof these required lane-changes are across a single lane line which is referred to as a crown line. The crown line is a lane line that joins the nose of the merge junction directly to the nose of the diverge junction. While one lane-change is required of all weaving vehicles, they may make additional lane-changes on a discretionary basis. The importance of the required lane-changes is that they must take place within the limits of the weaving section.A型配置。最常见的A型配置常被称为匝道交织（图13.41a）。它是由一条入口匝道、一条出口匝道通过通过一条连续的辅道连接而成。A型交织配置的特点就是每一个交织车量必需做车道变换一次。此外，所有的这些需要变道的都要穿过单行车道基准线，这车道基准线就 被称为路拱线。路拱线它是一条水平线，它连接合流和分流鼻端。然而一次变道是所有交车辆必须的，它们也许会按照基本规则随意地做额外的变道。变道最重要的要求就是他们须在交织区域限定的范围之内。The second form of Type A weaving configuration (Figure 13.4 lb) has similar characteristics, in that a crown line exists and all weaving vehicles must make one lane-change across it. It is formed, however, by a major merge junction and a major diverge junction (i.e., both legs have multiple lanes). While the lane-changing patterns are similar to those of ramp-weaves, there is a difference in operating characteristics. As weaving vehicles in a ramp-weave either originate from or are destined for a ramp roadway with restrictive geometry, they are generally accelerating or decelerating through the weaving area. When formed by a major merge and diverge junction, vehicles are more likely to be entering and leaving the section at freeway speeds. The analysis methodology of HCM 2000 was calibrated primarily for第二种形式的A型交织配置(图13.41b),有相似的特点，有路拱线存在而且当穿越它时所有车辆必须做一次变道。然而,它被一个主要合流点,一个主要的分流点(例如,两个匝道有多个车道)形成。而换道模式与匝道交织相似，只是在操作特性方面有所不同。在匝道交织处的车辆要么就是起源于严格几何形的缓坡道要么就注定是缓坡道的，他们通常是加速或者减速通过交织区域。一旦形成较大的合流点和分流点时，车辆就很难以高速通过这个区域。HCM2000的分析方法主要是对匝道交织区域标准化而且更加接近于A型配置。这种类型的A型配置如图13.41b所示，然而，它也是很少见的。图中单词：Ramp-Weave 匝道交织MajorWeave 主道交织Major Weave with Lane Balance at Exit Gore 出口三角形处的带有平行分流车道的主道交织Major Weave with Merge at Entry Gore 进口三角形处合流的主道交织Major Weave with Merge at Entry Gore and Lane Balance at Exit Gore 入口三角形处合流且出口三角形处有平行分流车道的主道交流Major Weave Without Lane Balance or Merging没有任何分流和合流的主道交织Two-Sided Weave 两边交织Figure 13.4: Weaving Area Configurations Illustrated (Used with permission of Transportation Research Board, National Research Council, Highway Capacity Manual, 2000, Exhibits 13-8, 13-9, and 13-10, pgs. 13-15, 13-16, and 13-17.)图13.4：交织区域配置说明（运输研究委员会，国家许可使用研究理事会，公路通行能力手册，2000年，在13-8，13-9，和13-10，编注。 13-15，13-16和13-17。）
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