高密度城市建成环境下线性交通基础设施复合化：发展、模式与特征

Linear Transportation Infrastructure Integration in High-Density Urban Built Environments: Evolution, Models, and Characteristics

关键词:  风景园林  高密度城市建成环境  线性交通基础设施  复合化  演变特征  设计模式

Key words:  landscape architecture  high-density urban built environment  linear transportation infrastructure  integration  evolutionary characteristics  design model

摘要:

高密度城市建成环境下，线性交通基础设施的建设逐步走向复合化发展。探究线性交通基础设施复合化的立体空间组织逻辑，构建复合化设计的基本模 式框架，对提高高密度城市空间效能和实现城市可持续发展具有重要意义。以城市线性交通基础设施的阶段性演变为主线，结合典型案例剖析，归纳出其由美学 导向的城市道路建设，转向功能主义主导的交通系统建设，再到当前复合化发展的演变路径。现阶段的复合化建设以地面立体化为核心，发展出3类空间复合类 型：地面空间与高架空间的复合、地面空间与浅层地下空间的复合、高架-地面-浅层地下空间的综合复合。在不同空间复合类型下，进一步提炼出4类基本复合设 计模式：上跨复合廊道、下嵌功能网络、上盖复合基面、多维系统叠合，并归纳其特征、建设方式与适用场景。结合实践经验，进一步探讨复合设计模式在中国 本土制度环境下的实践路径，指出复合化设计模式作为具有方法论意义的通用空间设计范式，亟须在实施落地的过程中探索与本土制度适配的建设路径。通过建 立灵活的用地混合与审批机制、多元主体协作机制，可为高密度城市中交通基础设施复合化建设提供可参考的路径支持。

Abstract:

In high-density urban built environments, linear transportation infrastructure has experienced a progressive shift from mono-functional engineering systems toward composite, multi-functional, and spatially integrated development. This evolution reflects the growing demand for space-efficient, ecologically sensitive, and socially responsive urban solutions under constraints of limited land, growing environmental awareness, and increasing complexity of urban systems. As cities face mounting challenges of land scarcity, fragmented spatial patterns, and functional segregation, there is a pressing need to reconceptualize infrastructure not only as a technical facility but also as a spatial and social resource. Understanding the three-dimensional spatial logic behind such composite infrastructure and establishing a systematic framework of composite design models are therefore crucial to improving spatial performance, optimizing land use, and promoting sustainable development. This study systematically traces the transformation of urban linear transportation infrastructure through three historical stages. The first stage is characterized by aesthetic-led urban road construction, emphasizing spatial order, streetscape improvement, and civic identity. The second stage, primarily driven by functionalist planning and modernist engineering, prioritized vehicular efficiency, large-scale connectivity, and mono-functional zoning, often at the expense of spatial integration and pedestrian environments. Entering the third stage, linear transportation infrastructure increasingly incorporates diverse functions, reflecting a composite logic that integrates transportation, ecological infrastructure, public life, and cultural expression within a unified spatial system. In the contemporary phase of composite development, vertical spatial integration at the ground level becomes the organizational core. Based on representative case studies, the study identifies three major types of spatial composites: 1) ground-elevated space integration, 2) ground-shallow underground space integration, and 3) fully integrated elevatedground-shallow underground systems. Each type demonstrates a distinct spatial logic of vertical stacking and functional layering, enabling the coexistence and coordination of transportation infrastructure with urban landscape, ecological systems, and public amenities in compact, high-density environments. Building upon these spatial integration types, the research further extracts four fundamental composite design models that guide linear infrastructure organization: elevated corridor integration, embedded functional networks, ground-level deck structures, and multi-dimensional system overlays. Each model is analyzed in terms of spatial characteristics, construction strategy, integration logic, and suitable application contexts. Collectively, these models constitute a landscape-oriented composite design framework for urban linear transportation infrastructure, aiming to reconcile efficiency with ecological sensitivity and public value. As a universally applicable spatial design paradigm with methodological significance, composite design models must be examined in light of local institutional conditions to be effectively implemented. Drawing on a series of representative case studies and the authors' professional design experiences, this study investigates how these models interact with China's current institutional and regulatory systems. Compared with the relatively flexible zoning, land-use, and approval mechanisms commonly found in Western contexts, China's land management framework is characterized by a rigid "land-use-function-ownership" one-to-one correspondence. Moreover, the administration of land parcels by separate government departments based on use category poses significant challenges for accommodating multi-functional and cross-boundary spatial configurations. These institutional rigidities often result in high implementation thresholds and resistance when applying composite design models in practice. In response to these constraints, the study proposes a set of feasible strategies to facilitate composite infrastructure development under China's planning and governance system. These include establishing flexible land-use mixing mechanisms, simplifying and streamlining approval processes for integrated projects, and building collaborative governance frameworks that enable effective participation by multiple stakeholders across both public and private sectors.