*3.3. Analysis of the Spatial Distribution and Reuse Status of Industrial Heritage by Resource Type* 3.3.1. Reuse and Conservation Status Statistics

As of June 2020, the Tianjin Industrial Heritage Census GIS Database contains 111 items of industrial heritage. Of these, 16 are protected and 95 are not on the Chinese government's cultural heritage protection list at all levels. Among the 16 protected heritages, there are 4 national-priority cultural relic protection sites, 10 municipal-level cultural relic protection sites and 2 historical buildings of Tianjin (Figure 6a). It can be seen that the current state of conservation of industrial heritage in Tianjin is poor. The number of protected industrial heritage sites is very small, accounting for only 14.4% of the total; moreover, among the 16 protected industrial heritage sites, most of them are mainly industrial ancillary heritage sites such as office buildings. There is less protection for industrial heritage plants. The reuse of industrial heritage is dominated by cultural and creative parks and commercial buildings, accounting for 72.4% of the total, which shows that the reuse mode of heritage is relatively homogeneous and needs to be developed (Figure 6b).

**Figure 6.** Current status of conservation and reuse of Tianjin's industrial heritage: (**a**) statistical map of the levels of protection of industrial heritage in Tianjin; (**b**) statistical map of the types of industrial heritage reuse in Tianjin.

In summary, the rational reuse of heritage that is not covered by the conservation system has become an important issue in Tianjin's industrial heritage.

#### 3.3.2. Analysis of Industrial Heritage Resource Types and Their Reuse

With regard to the types of industrial heritage, previous studies have classified the types of industrial heritage in terms of the production industries and scale hierarchies and summarized the reuse patterns of different types of industrial heritage [47,48]. Based on relevant studies, the author combined the specific resource types of industrial heritage sites in Tianjin and divided them into three major categories, namely, plant type, building type and structure type, according to the differences in their material composition types (Figure 7), and typical examples of each resource type of industrial heritage are shown in Figure 8. The resource types of industrial heritage and their spatial distribution are important factors influencing the reuse of heritage [49]. Statistics on the number and reuse status of the three types of industrial heritage are shown in Figure 9. The current state of industrial heritage reuse varies greatly between the different types. The plant type and building type are relatively good, but the structure type, not yet.

**Figure 7.** Resource types of industrial heritage in Tianjin and their characteristics.

**Figure 8.** Typical examples of industrial heritage in Tianjin by resource type: (**a**) plant type: Baochengyu Big Yarn Factory before and after renovation; (**b**) building type: the former Jardine Matheson building; (**c**) structure type: Wanguo Bridge.

**Figure 9.** (**a**) Statistical map of the resource types of industrial heritage in Tianjin; (**b**) statistical map of the current status of reuse of industrial heritage resource types in Tianjin.

#### Plant Type

The plant type refers to the existence of industrial heritage in the form of an industrial factory, which generally includes the industrial heritage environment, the heritage of industrial buildings and structures and the heritage of industrial equipment. This type of industrial heritage covers a larger area, usually several hectares to several dozen hectares, or even hundreds of hectares, and contains a richer heritage. It has higher heritage value and higher reuse value and possibilities.

The results of the analysis of the distribution of the plant-type industrial heritage using GIS kernel density estimation are shown in Figure 10a. The plant-type industrial heritage in Tianjin is mainly distributed in the six districts of the downtown and the Binhai District; there are particular concentrations in the Hebei District and Binhai District at the Haihe River estuary, and there is a smaller amount in other areas. This result is closely related to the modern urban development of Tianjin. Statistics on the number of plant-type industrial heritage sites and the number of adaptive reuse sites in all districts and counties of Tianjin are shown in Figure 10b. The reused plants in Tianjin are mainly concentrated in the six districts of the downtown area, and the number of reused plants in some districts is close to half of the total plant-type industrial heritage in those districts, and the form of use is mainly cultural and creative industrial parks. Other districts and counties have very few reused factory sites, and Binhai District has the largest amount of existing plant-type industrial heritage, but only one example of a reused plant.

**Figure 10.** (**a**) Analysis of the kernel density of plant-type industrial heritage in Tianjin; (**b**) statistics on the total amount of plant-type industrial heritage sites and the amount of their reuse in Tianjin by district.

A comprehensive analysis of the distribution and reuse status of the plant-type industrial heritage shows that the areas with the greatest reuse potential are concentrated in Binhai District, followed by Hedong District, Hebei District and Nankai District; Heping District, Hexi District and Hongqiao District have less potential for reuse due to the small amount of land reserves in the factory area.
