这项耗资16亿美元的Wekiva Parkway项目，是佛罗里达州中部高速公路管理局（CFX）和佛罗里达州运输部（FDOT）的联合努力（FDOT），在全国和本地受到称赞，这是基础设施建设者与环境兴趣之间的合作计划的一个杰出典范。小组。（新利luckENR 8/15p。52）但是，一个25英里长的项目位于奥兰多以北佛罗里达州中部的大多数农村地区（佛罗里达州不寻常的滚动地形），这也是公路建造者设计和设计和设计的同样难得的机会在绿地环境中构建真正的“大路”。
With both agencies mandated by Florida law to construct the nascent toll road as a “parkway”—though state legislators offered few other guidelines—officials with CFX and its engineering consultants began the business of determining what constituted such a designation.
Wekiva Parkway走廊顾问CH2M计划经理Scott Bear说，该州提供了“相当广泛的定义”。区域运输管理局及其顾问及其顾问在确定公园大道指南的领导下，是因为其部分是第一个建造的部分。
“Our task was to make sure there was consistency” for the entirety of the 25-mile-long tollway,” Bear says. “A lot of discussion” ensued, he adds, with topics including the use of hardscape features, landscaping, the incorporation of natural buffers and even avoiding the creation of “BURPS”—short for big, ugly, rectangular ponds—when constructing the necessary water retention areas.
CFX工程总监Glenn Pressimone肯定是一件事：建造公园大道的任务“不会只是将混凝土和沥青扔在那里。”
Seeking inspiration from existing parkways such as the Blue Ridge and others in New York and elsewhere, “We tried to keep as much of a rolling terrain” as possible, Bear says.
Bifurcation, or separation, of opposing travel lanes by utilizing wider medians, a fairly common approach, is another basic step being used to achieve a parkway feel. But Wekiva designers went a step further, by also using bifurcation on the vertical axis—a feature made possible by the area’s hilly terrain.
“So your northbound lanes could be anywhere from 7 to 10 feet below the southbound lanes,” Pressimone explains.
By having one set of travel lanes higher than the other, “You feel like you’re on a high-speed corridor,” Bear says.
总体而言，工程师还设计了一个部分，这两套旅行车道都位于现有地形以下。
“We’re in a relatively rare part of the state where the water table is deep, so we can actually bring the roadway template down,” says Don Budnovich, CFX resident engineer. For instance, in one 1.5-mile-long stretch currently under construction, the mainline gradually dives nearly 25 ft below its natural elevation. This particular section almost went in the opposite direction, though, with early designs elevating the roadway by as much as 25 ft, Pressimone says.
“When we saw early cross sections, we saw that was a lot of dirt,” he says of the amount of fill that would’ve been required. However, project team members quickly began second-guessing that approach and started wondering about the water table and the possibility of doing a cut section—a relatively uncommon tactic for Florida, given its usually shallow water table.
But “lo and behold,” Pressimone says, “the water table was in our favor in those sections.”
Another standard approach to enhanced aesthetics that the project owners and engineers flipped in a non-standard way involved the detailing of the MSE (mechanically stabilized earth) walls supporting elevated sections.
Pressimone说：“我们想要一些有很多揭示的东西。”他补充说，目的是尽可能模仿天然石头。该项目团队最终定居在MSE墙壁上的弧形石材衬里，但事实证明，选择过程艰苦。
Design of these units was “easily a six-month or more process,” Bear says. “There was a lot of time spent on the finish of those retaining walls.”
For instance, instead of just painting the wall units, the project team devised a multi-step coating system comprising three differently colored stains that are sprayed on and, in some cases, sponged on.
Since the items would be used throughout the length of the 25-mile roadway—which is being built via separate contracts, contractors and even owners—the project team went through an exhaustive effort of producing multiple mock-ups in order to formally specify the production process and end result in the bidding documents.
Also, after deciding on a particular aesthetic, the project team kept those early mock-ups on hand, which suppliers must prove they can match perfectly before beginning work. To date, though, only one firm, Finishing Systems of Florida, has won the job for all awarded sections, according to CFX. Even so, it took “seven or eight” attempts to match the early mock-ups, Pressimone says.
Haunches for Arches
Pressimone简单地说明了实现大路感觉的另一个早期想法：“让我们扔一些拱门。”但是，实现这一现实将变得更加复杂。
To incorporate the arch look, the project team is using haunched beams for as many of the bridge structures as possible. (While most are concrete beams, some steel beams were required.)
One critical portion of the project is Section 2B, a 1.5-mile-long segment otherwise known as the Systems Interchange, which is being constructed by Southland Construction Co. under a $79.6-million contract. The contractor has a hard-and-fast deadline of January 2018, due to the segment’s function linking the new tollway with the existing S.R. 429.
Albertos Ribas说，这里的2,550英尺长的坡道K超过429（依次飞过了当地的道路）是承包商的关键道路。坡道K构造由五个单元组成，共同包括17个跨度，每个跨度为150英尺，总共有58个U-Girder Beams，其中44个均匀。单位1和2每个尺寸为600英尺，包括四个跨度，而单位3、4和5尺寸为450英尺，包括三个跨度。
里巴斯说：“坡道k将是首先要开始的事情，这将是最后要结束的事情（构造）。”“它主导了该项目的整个时间表。”
Including the haunches in the beams, which adds weight, affected span lengths in some instances and otherwise challenged designers.
According to Kenneth Zagers, senior project manager with Atkins, and engineer of record for the Ramp K bridge, the structure uses PCI Zone 6 (Southeast region) U-girders, modified to include a haunch that varies between 72 in. and 115 in. in depth, depending on location.
Zagers通过电子邮件指出，Zagers指出，“ haunches是一种审美要求，增加了建模形状的复杂性。”新利luck例如，他说：“我们必须使用二级多项式来定义heaunch的曲线，以便准确确定结构中的应力。”
有三种基本段类型：末端段，其中包括一端的he键；中间部分，中间倾斜；和跨度片段，缺乏haunch并保持恒定的72英寸深度。
Fabricating the haunched beams—some of which measure nearly 10 ft in height, versus the standard 6 ft—also proved more complex than usual, and added costs, says the precaster.
除了要求购买的新形式haunched sections, “It also required our workers to be much higher in the air while tying the steel and placing the concrete for the members,” says Tim Morley, general manager for Dura-Stress. Additionally, the height of the beams and the additional steel reinforcement required to form the haunch sections resulted in more man-hours and a longer production cycle, he says. (Project officials admit that designing and constructing to parkway specifications adds a significant amount to the overall cost.)
Beam production is scheduled to commence in September, with delivery of the first beams set for October. So far so good for this critical segment, says Ribas: “(Southland’s) work on the substructure work is going extremely well. We are definitely on schedule.”
