Truss optimization is a rich research field receiving renewed interest in limiting the carbon emissions of construction. However, a persistent challenge has been to construct highly optimized and often complex designs. This contribution formulates and solves new mixed-integer linear programs that enable consideration of the interplay between environmental impact and constructability. Specifically, the design engineer is enabled to design with multiple materials and/or structural components, apply separate minimum and maximum cross-sectional area bounds, and constrain the complexity of the structural connections. This is done while explicitly considering compatibility and constitutive laws. The results demonstrate that the lowest embodied carbon designs change significantly when constructability constraints are applied, highlighting the need for an integrated optimization approach. In one example, introducing a lower-carbon material option has almost no effect on the environmental performance, whereas another sees an improvement of nearly 29%. The extensibility of the formulation to design with three component types and additional constraints is demonstrated for a prestressed tensegrity example.

翻译：桁架优化是一个丰富的研究领域，在限制建筑碳排放方面重新受到关注。然而，一个长期存在的挑战是如何构造高度优化且通常复杂的设计。本研究提出并求解了新的混合整数线性规划模型，使得能够同时考虑环境影响与可建造性之间的相互作用。具体而言，设计工程师能够在设计中采用多种材料和/或结构组件，分别应用最小和最大横截面积约束，并限制结构连接的复杂性。这一切都是在明确考虑相容性和本构定律的前提下完成的。结果表明，当施加可建造性约束时，最低隐含碳排放设计会发生显著变化，这突显了采用集成优化方法的必要性。在一个示例中，引入低碳材料选项对环境性能几乎没有影响，而另一个示例则实现了近29%的改善。通过一个预应力张拉整体示例，展示了该公式可扩展至三种组件类型及附加约束的设计能力。