Cortesia de E. Baharlou

自然与技术：可以种植植物的墙体
Nature and Technology: Walls That Can Grow Plants

由专筑网Zia，小R编译

建筑和自然之间的关系是复杂的。如果说，一方面我们喜欢在家里把自然作为艺术的表现；另一方面，我们不惜一切代价避免在墙壁和结构中出现阻碍性的“真实”的自然环境，因为结构会被这些树根和枝叶损坏。同时，我们使用绿色屋顶、垂直花园和花箱，使城市更接近自然，以改善人们的体验；但我们也用完全脱离动植物的材料建造建筑。尽管生物材料和新技术的进步正在逐步改变这种状况，但我们还是应该问自己，我们所居住的结构和建筑是否需要与它们周围的自然完全分开。这就促使了弗吉尼亚大学（UVA）的研究人员开发几何形状复杂的3D打印土壤结构，使植物可以在上面自由生长。

该团队开发了一种用生物材料进行3D打印的方法，将循环性纳入了这个过程。使用的原材料不是传统的混凝土或塑料材料，而是土壤本身和当地植物与水的混合物，形成墙壁和结构。通过将速度、成本效益和低能源需求与当地采购的生物基料相结合，制造的过程可以发展并创造出完全可生物降解的3D打印结构，在其使用寿命结束后返回地球土壤。

The relationship between architecture and nature is complex. If, on the one hand, we enjoy framing nature as art in our homes; on the other hand, we try at all costs to avoid the presence of obstructive "real" nature in our walls and structures, which can be damaged by roots and leaves. At the same time, we use green roofs, vertical gardens and flower boxes to bring cities closer to nature and improve people's wellbeing; but we also construct buildings with materials that are completely dissociated from fauna and flora. Although the advancement of biomaterials and new technologies is gradually changing this, we should nevertheless ask ourselves whether the structures and buildings we occupy need to be separated from the nature that surrounds them. This was the question that led researchers at the University of Virginia (UVA) to develop geometrically complex 3D-printed soil structures on which plants could grow freely.
The team developed a method for 3D printing with bio-based materials, incorporating circularity into the process. Instead of traditional concrete or plastic materials, the raw material used is the soil itself and local plants mixed with water and inserted into the printer to form walls and structures. By combining the speed, cost efficiency, and low energy demands with locally-sourced bio-based materials, the process of additive manufacturing can evolve and create 3D-printed structures that are completely biodegradable, returning to the earth at the end of its useful lives.


© Tom Daly

该团队由弗吉尼亚大学工程与应用科学学院科学与材料工程助理教授Ji Ma、弗吉尼亚大学环境科学系研究教授David Carr、弗吉尼亚大学建筑学院助理教授Ehsan Baharlou以及该大学的学生Spencer Barnes组成。Barnes通过两种方法对最有利于打印的混合物进行了实验：将土壤和种子按顺序分层打印，或在打印前将种子与土壤混合。这两种方法效果都很好。

正如Ji Ma在该大学发表的这篇文章中指出的那样，“3D打印的土壤往往会更快地失去水分，并对其拥有的水分保持更强的控制力，因为3D打印使植物周围的环境更加干燥，所以我们必须将喜欢干燥气候的植物纳入其中。我们认为出现这种情况的原因是土壤被压实了。当土壤被挤压通过喷嘴时，气泡被挤出。而当土壤失去气泡时，它就会更加锁水。”

The team consisted of Ji Ma, Assistant Professor of Science and Material Engineering at the School of Engineering and Applied Science at UVA; David Carr, Research Professor at the Department of Environmental Sciences at UVA; and Ehsan Baharlou, Assistant Professor at the UVA School of Architecture, as well as Spencer Barnes, a student at the University. Barnes conducted experiments on the most conducive mixtures for printing, through two approaches: printing soil and seeds in sequential layers or mixing seeds with the soil before printing. Both approaches worked well.
As Ji Ma points out in this article published by the University, “3D-printed soil tends to lose water more quickly and keeps a stronger grip on the water it has,” Ma said. “Because 3D printing makes the environment around the plant drier, we have to incorporate plants that like drier climates. The reason we think this is the case is because the soil gets compacted. When the soil is squeezed through the nozzle, air bubbles are pushed out. When the soil loses air bubbles, it holds onto water more tightly.”


Cortesia de E. Baharlou

而David Carr则负责寻找理想的打印土壤成分和最有利的植物种类。这些发现将确保植物可以在结构内生长繁殖，土壤可以积累有机物并收集必要的营养。他提议种植那些自然生长在似乎处于生命外部极限的地区的植物——那些几乎生长在裸露岩石上的本地植物。选择的物种是Sedum（石竹），通常被用于种植屋顶。这个物种的生理结构与仙人掌相似，它可以在很少的水分环境中生存，甚至可以在一定程度上经历干涸的环境，而后恢复。

David Carr, in turn, was responsible for finding the ideal composition of the soil for printing and the most conducive plant species. These findings would ensure that the plants could prosper within the structure and the soil could accumulate organic matter and collect necessary nutrients. He proposed plants that grow naturally in areas that seem to be on the outer limits of life - native plants that grow practically on naked rocks. The chosen species was Sedum (Stonecrop), commonly used in green roofs. The physiology of this species is similar to the cactus and it can survive with very little water, and can even dry up to some extent in order to recover.


Cortesia de E. Baharlou

该团队今年早些时候发表了《3D打印生态活性土壤结构》的论文，宣布了他们的第一个成果。围绕该技术的研究一直在继续，接下来的步骤包括为至少有一层楼的大型结构提供土壤 配方，寻求预测解决在较大的张力下土壤开裂等问题。此外，研究人员还试验了墙板内的各种面层，以便隔离内墙和外墙的湿度。虽然这只是一个开始，但它可以成为使自然环境更接近人类制造的一个步骤。

The team published their first results earlier this year in the paper entitled 3D Printing of Ecologically Active Soil Structures. Research around the technology has continued and the next steps include soil "ink" formulations for larger structures with at least one floor, seeking to anticipate problems such as soil breakage in larger tensions. In addition, researchers have also experimented with various layers within a wall panel in order to isolate the inner wall and maintain the moisture of the outer wall. Although it is just a start, it can be a step towards keeping nature closer to human manufacturing.


© Tom Daly


Cortesia de E. Baharlou