不同天然海绵体特征条件下的海绵城市建设适宜性研究

Research on the Different Natural Geological Impact and Suitability of Sponge City Construction

海绵城市建设是近年来城市规划和雨洪管理的重要方向。针对不同的地质环境条件特征,海绵城市建设的适宜性和措施建议各不相同。本文通过对郑州市白沙和高新两个典型地貌单元的海绵城市建设示范区进行研究,在查明区域地质环境条件的基础上,运用层次分析法对两个示范区的天然地质海绵体的适宜性进行评价。评价指标选取地表海绵体中的土地利用现状、地表岩性、地形坡度、土壤环境质量,地下海绵体中的岩性结构组合、厚度。评价结果显示白沙示范区适宜性整体优于高新示范区一个级别。白沙示范区浅层地下水埋深较浅,地层渗透性强,若加大开采力度,其海绵城市建设的蓄水能力会大大增强,海绵城市建设的适宜性也会随之提升;高新示范区虽水位埋藏深,但地层渗透性差,海绵城市建设潜力相对较小。针对不同的天然海绵体条件特征,应辅以相应的LID设施建议。

The construction of sponge cities has been an important issue in urban planning and stormwater management in recent years.The suitability and recommended measures for building sponge cities are different according to the different characteristics of geological environment.This study investigated two sponge city construction demonstration zones of typical geomorphic units including the Baisha and High-Tech areas in Zhengzhou.The analytic hierarchy process(AHP)was adopted to evaluate the suitability of the natural geological sponge entities in the study areas.Evaluative index system included land use,lithology,terrain slope and soil quality of surface and the composition and thickness of subsurface lithology based on identifying the geological and environmental conditions of the area.The results show that the suitability of Baisha was better than the High-Tech zone.Because of the high permeability of the geological strata and the shallow depth of the groundwater table,if the intensity of groundwater exploitation increased the better suitability of Baisha will be greatly enhanced.The suitability of the High-Tech zone is relatively poor because of poor permeability of the geological strata.The suggestions for corresponding low impact development(LID)facilities were given based on different natural sponge entity conditions.