Three-dimensional morphological research on the alley space of Lilong Housing — A comparative study of Japanese and French Concession in Tianjin, China

Lilong housing as a kind of dwelling housing was born during the modernization process of Chinese housing from 1840s. Large amounts of Lilong Housing were constructed in Tianjin from 1860s to 1940s, which formed the basic city fabric till now. Many researches focus on alley space which is very typical in Lilong housing, and some achieves are of classification by typological methods. However, most of them are based on planar analysis, though the space of alleys is three-dimensional, and the difference between different Concessions are rarely mentioned. This paper focused on the alleys' three-dimensional morphological characteristics, especially on the aspect ratio and the interface changing in different alleys in the sequence from the city to the house. Meanwhile this study is based on the previous classification of alley's structure: line-type, fishbone-type and loop-type. Firstly, the typology depth of planar structure is studied base on the previous classification. Secondly, the redefined Alley Aspect Ratio is calculated, clear differences between Japanese Concession and French Concession are shown. Finally, typology depth was connected to the section according to the planar structure to reveal the prototype of alley space in different Concessions. According the research, it is found that 3D characteristics have remarkable differences in the same planar type. Further, the spatial characteristic of alleys has different tendency between two Concessions. Therefore, this paper suggests that in the colonial period, the planning concepts of different colonial countries guided the construction of Concessions, and ultimately acted on the alley spaces of the residence. This paper provides new perspective to explain the forming reasons of the complex urban fabric of Tianjin in modern times