由弗吉尼亚理工大学师生设计的获奖观景塔,将最先进的木材研究与创新的非现场组装方法相结合。这个最近在弗吉尼亚州农村完成的项目通过使用该大学自己的跨学科研究,展示了一种独特的低碳设计和施工方法。

The award-winning observation tower, by Virginia Tech students and faculty, pairs cutting-edge timber research with innovative off-site assembly methods. The recently-completed project in rural Virginia demonstrates a unique approach to low-carbon design and construction through the use of the university’s own interdisciplinary research.

项目介绍。2018年,弗吉尼亚州拉德福德的河滨城市找到了弗吉尼亚理工大学–一所附近的公立研究型大学–协助该镇对新的火车观景塔进行设想,该观景塔将为公众提供俯瞰邻近新河和具有历史意义的铁路桥的机会。该市的一个主要项目目标是使用清洁技术、低碳建筑产品,作为展示该市从过去的工业化转型的一种方式。在接下来的两年项目期间,一个跨学科的教师和学生团队合作研究、设计并建造了这座75英尺长、30英尺高的公共建筑。

Project introduction. In 2018, the riverfront city of Radford, Virginia approached Virginia Tech – a nearby public research university – to assist the town with the visioning for a new train observation tower that would provide public access to views over the adjacent New River and a historically significant railroad bridge. A primary project objective for the city was the use of clean-tech, low-carbon building products as a way to showcase the city’s transition away from its industrial past. Over the following two-year project period, an interdisciplinary faculty and student team partnered to research, design, and build the 75-foot long by 30-foot high public building.

在设计过程的早期,学生们选择关注新兴的建筑技术–交叉层压木材(CLT)–因为它的强度、可持续性和独特的空间属性。随着设计进程的推进,项目组发现将工业化生产的交叉层压木板运到项目现场的碳成本太高,因此,项目组被迫 “从本地考虑 “以降低碳成本,这就需要创造性地应用本地原材料。

Early in the design process, the students chose to focus on emerging building technology – cross-laminated timber (CLT) – due to its strength, sustainability, and unique spatial properties. As the design process progressed, the project team discovered that the carbon cost to ship industrially produced cross-laminated timber panels to the project site was too high and, as such, the project team was forced to “think local” in order to cut carbon costs, thus entailing the creative application of locally-sourced raw materials.

低碳产品的开发。经过大学多个院系多年的研究,最终定制开发的硬木交叉层积材(HCLT)产品采用了从供应过剩、硬木为主的森林中获取的低等级黄杨木。定制的HCLT产品不仅性能优于美国市场上所有其他商业化的CLT–主要由软木制成–而且该产品的原材料也是在项目现场方圆两百英里范围内采购和回收的。

Low-carbon product development. Following the culmination of years of research across multiple university departments, the resulting custom-developed, hardwood cross-laminated timber (HCLT) product utilizes low-grade Yellow Poplar lumber regionally sourced from oversupplied, hardwood-dominant forests. The custom HCLT product not only outperformed all other commercially available CLT in the U.S. market – notably made from softwoods – but the product’s raw materials were also sourced and up-cycled within a two-hundred-mile radius of the project site.

随着研究从实验室样品的规模开始,并最终形成了5英尺×10英尺的高强度板材,学生和教师团队能够将独特的建筑特征融入到项目中,以符合HCLT的强大性能指标,即3英寸厚的结构悬臂和外部暴露的结构件。

With research beginning at the scale of a lab sample, and resulting in the 5-foot by 10-foot high-strength panels, the student and faculty team was able to incorporate unique architectural features into the project that aligned with the HCLT’s robust performance metrics, namely 3-inch thick structural cantilevers, and the exterior exposed structural members.

随着研究从实验室样品的规模开始,并产生了5英尺乘10英尺的高强度面板,学生和教师团队能够将独特的建筑特征纳入该项目,以符合HCLT的强大性能指标,即3英寸厚的结构悬臂和外部暴露的结构件。

With research beginning at the scale of a lab sample, and resulting in the 5-foot by 10-foot high-strength panels, the student and faculty team was able to incorporate unique architectural features into the project that aligned with the HCLT’s robust performance metrics, namely 3-inch thick structural cantilevers, and the exterior exposed structural members.

模块化施工。该项目位于新河之上的一个陡峭的棕色场地上,具有挑战性的场地条件要求项目团队在一个受控的环境中进行建筑部件的场外预制。该项目的建筑设计包括两个模块化的HCLT立方体,被一条公共走道分隔开。人行道从地面开始,随着场地向河边的陡然下降,最终形成一个20英尺高的悬挑。

Modular construction. Perched above the New River on a steeply sloping brownfield site, the challenging site conditions required the project team to prefabricate building components in a controlled environment offsite. The project’s architectural design involves two modular HCLT cubes that are bisected by a public walkway. The walkway begins at grade and culminates in a 20-foot-high cantilever as the site drops steeply towards the river.

由于复杂的现场物流,包括在施工过程中在项目地基下发现的内战时期的建筑废墟,项目团队完全预制了一个10英尺×15英尺的HCLT模块,然后用起重机在现场吊装到位,与周围的树木保持6英寸的距离。新河列车观景塔是全球第一个在永久性建筑中使用模块式HCLT施工方法的项目,因此需要进行独特和仔细的细节设计,以保持悬臂式、面板式系统的水保护,并在施工过程中避免架子的安全。

Due to complicated site logistics, including the ruins of a Civil-war era building discovered under the project’s foundations during construction, the project team entirely prefabricated one 10-foot by 15-foot HCLT module that was then subsequently craned into place on-site, with a six-inch tolerance from surrounding trees. The New River Train Observation Tower is the first project globally to utilize modular HCLT construction methods in a permanent building, thus entailing unique and careful detailing to keep the cantilevering, panelized system water protected and safe from racking during construction.

该项目也是全球独一无二的由层压硬木制成的外部暴露的结构元素的例子。每一个螺丝孔都用液体蜡浸渍,然后整个外部围护结构被涂上亚麻籽油和天然松油混合物,以保护其免受紫外线、热量和湿气的损害。

The project is also globally unique as an example of exterior-exposed structural elements made from laminated hardwood. Each screw hole was impregnated with liquid wax, and then the entire exterior envelope was coated in a linseed oil and natural pine tar mix to protect it from UV, heat, and moisture damage.

该项目是美国允许的第一个永久性的、HCLT建筑。而且,通过研究和开发过程,对低价值的本地材料进行定制的升级回收试点,它为低碳、基于研究的可持续建筑树立了一个基准。

The project is the first permanent, HCLT building permitted in the United States. And, through a research and development process that piloted the custom up-cycling of low-value locally sourced materials, it sets a benchmark for low-carbon, research-based, sustainable construction.

Architects: Virginia Tech
Year : 2021
Photographs :Kay Edge and Edward Becker
General Engineering : Truesdell Engineering
Project Architects : Edward Becker, Kay Edge
Design Team : Kirt Hilker, Robert Riggs, and Virginia Tech students
Collaborators : Dr. Daniel Hindman, Dr. Tom Hammett, Dr. Henry Quesada, Dr. Joseph Loferski, Dr. Brian Bond
Suppliers : Henard Metal Fabricators, Walder Foundation Products, Helix Steel, Chandler Concrete
City : Radford
Country : United States