在过去的十年中，随着人口的巨大增长和学生入学率的增长，北弗吉尼亚州的阿灵顿公立学校面临着新的挑战：在茂密的城市环境中新利18备用创建学校。这个挑战的一个主要例子是威尔逊中学耗资1亿美元，现在正在建设中。设计和建筑团队计划于2019年秋季完成，旨在在罗斯林（Rosslyn）的高层建筑走廊上提供181,803平方英尺的建筑，就在华盛顿特区的波托马克河对面。

该建筑在年级高出五个故事中，但建筑师Big开发了一个创造性的概念，可以在每个楼层提供教室，从而为学生带来一层楼的学校的体验。

不寻常的城市概念取决于一系列的课堂级别，这些课程从一个枢轴点扇出。视觉效果类似于打开手持风扇。通过扇形布局，每个上层都可以进入以下水平顶部的绿色屋顶。从顶层开始，扇形的概念创建了一系列绿色屋顶，这些绿色屋顶沿着建筑物层叠，以下面的田径场结束。

“Every classroom has a garden outside of it,” says Jeffrey Chambers, director of Design & Construction for Arlington Public Schools (APS). “It’s amazing how much green space there will be. Standing on top and looking down, you will think it’s a hillside meadow, not a series of roofs.”

Tony-Saba Shiber, senior architect at BIG, says the collection of green roofs also will serve as an “extension of learning spaces within the school.” In addition to plants and trees, the rooftops will feature seating areas, where students can gather for outdoor classroom sessions.

为扇形地板创建一个中央枢轴点带来了重大的结构挑战。结构工程公司西尔曼（Silman）在混凝土电梯芯的中心周围建立了枢轴。该概念允许将完整的桁架完全组装成并安装在序列上。开发了一个“折叠式桁架”，一端弯曲90度。

The fold allowed the truss above to be set with two bearing points on the truss below: a panel point near midsection and a bearing point at the end of the folded truss. Instead of extending truss diagonals farther along the sides of each floor, Silman used a “floating buttress” concept by resolving out-of-plane forces through the diaphragms. Horizontal floor beams were arranged and designed to carry the diaphragm forces back to the rigid structural core.

Jason Myers, associate at Silman, says early iterations called for a helical column concept, but that would have created diagonal columns in interior spaces. “The architect wanted those columns pushed out for programmatic reasons, which led to the folded truss concept,” he says. “It’s a solution that is very unique [compared with other projects] in the local area.”

The rotation of the floors also created large voids below the classroom levels, which the design team filled with wide-span spaces such as a gymnasium, theater, library and atrium. The space over the theater was designed structurally with steel trusses using wide-flange sections to support theater loads and transfer columns from three stories above.

Silman developed a simplified set of connection details in collaboration with steel fabricator Banker Steel that allowed trusses to be set on top of supporting columns using a simple bearing connection. Intermediate trusses connect to the web of the supporting girder with simple bolted end plates.

Early in the project’s development, Gilbane, the construction manager at-risk, brought in Banker Steel and concrete contractor Baker DC to provide design-assist work for the unusual structural system. “We got a ton of value in bringing them in,” says Tyler Swartzwelder, Gilbane project executive. “There were wide-flange members that we couldn’t source domestically, so they came up with plate girders that could be fabricated in their own yard. The value in terms of erection, sequencing and constructibility feedback was huge.”

In total, Banker is providing 2,300 tons of steel on the project; the heaviest member weighs roughly 21 tons. “We had a lot of jumbo-shaped members on the job, which saves a lot of labor in the shop and helps us stay on schedule,” says Cody Mann, Banker’s project manager.

Adding to the logistical challenge—due to an unrelated project nearby—Arlington County had to temporarily relocate a firehouse to the part of the school’s project site where its future athletics field will be located. That greatly limited laydown space on the project and led to its tower crane’s being located in the building. Because of limited lift capabilities and a tight space to work within, several of the longest and heaviest steel members had to be spliced, then field-welded before erection.

Some trades, including steel and concrete, had to share use of that lone crane. As a result, Baker decided to build the entire concrete core before steel erection. Concrete work had to be extremely precise because multiple steel embeds needed to connect to the core at specific locations. Some of the embeds weighed nearly 800 lb and were up to 4 ft in length.

该项目是阿灵顿学区首次使用CM处于高风险交付方法。Swartzwelder表示，它使Gilbane在原理图设计期间加入了项目团队，事实证明，这对于早期解决挑战至关重要。吉尔班（Gilbane）不仅将设计辅助者用于钢铁和混凝土工作，而且还使用了MEP，窗帘墙以及床单和支撑。他说：“该策略的一部分是获得首选潜水艇的早期锁定。”“就采购策略而言，这对我们很重要。此外，当我们通过定价工作时，我们可以确保我们在这座复杂的建筑物上保持预算。事实证明，它非常有价值。”

For curtain wall work, the team worked with Glass Project Resources to design a unitized system that could be fabricated off site and quickly installed. “When the structure was done, [workers] came in and set 12 to 14 units per day,” Swartzwelder says. “The long face of one [floor] takes five days. That was a decision that was critical to the construction schedule success that we’ve had to date.”

The front lobby will feature a triple-span VS1 curtain wall system, which uses only vertical mullions and one tension rod located roughly two-thirds of the way up. “The glass stands off the mullions so it looks like it is floating,” he adds.

当新学校在2019年秋季向学生开放时，它将容纳该县现有的H-B Woodlawn中学，该中学专注于表演和视觉艺术，而Stratford计划则专注于学习和身体残疾的学生。在这些计划的学生中，有些人正在学习英语，而另一些则患有阿斯伯格综合症。在创建共同空间的同时，适应这些计划在平衡不同学生人群的需求方面给设计师带来了挑战。

确保周围建筑设计two specific, complex programs was critical, Shiber says. “A lot of [the design] was done working with APS to develop specifications for program sizes, what they wanted incorporated in this building and the specific program adjacencies that make all elements accessible to everyone.”

The main shared spaces, such as the theater, gym and cafeteria, are centrally located near the building’s main floor. Adjoining those shared areas are program-specific spaces, such as rehearsal and small performance areas that stack above and around the theater.

The building’s design is dramatic, but the interiors focus on function more than finishes, APS’s Chambers says. At Stratford’s existing location, interior space has been personalized by allowing students to paint and write on the walls. At the new school, too, he says, “We’re providing a blank canvas for them to make it their own.”