Abstract:
Urban climate is strongly related to topographies. The urban heat island is happening in the urban fabric when cold air zones appear in the open and green landscape. Due to climate change and urbanization, the urban heat island would hit more people harder. Therefore any potential urban cooling resources should be utilized. Thermal-driven winds between floodplains and built-up areas is highly valuable. In order to invite the cool breeze into Dutch cities, the dike that is currently playing the role of a barrier needs to be altered. A seasonal flexible flood defence alternative is believed to be possible because flood defence (winter to spring) and urban cooling (summer) are never needed at the same time.
To study the cool air exchange between the floodplain and the urban area and the hampering effect of the dike, the microclimate simulations were made through ENVI-met for the testbed. The simulations indicated that the cool breeze is happening between different topographies where the temperature difference occurs, and has the significant cooling effect in the neighbourhood. According to the findings, eight concept models were designed based on the idea of opening for ventilation and closing for flood protection. Along with the research through design process, these alternatives were improved, detailed and selected. Eventually, the inflatable dike partition, the modular & moveable floodwall and the gabion dike were considered to have the most efficient ventilation and the most stable structures for flood defence. After that, they were applied in the site-specific landscape design in order to explore social multifunctions the new structures could provide.
At the end of the research, three prototypes of the adjustable flood defence structure were generated to replace the traditional Dutch dike, where heat problems is adjacent to the floodplain. In addition, both the neighbourhood-oriented and tourist attractive multifunctions were identified for each alternative.
