Study On The Construction Plan And Effect Of Xianyang City With The Concept Of Sponge City

The lack of water resources,serious over-exploitation of groundwater,and a drop in water level in Xianyang City have caused serious environmental disasters.In order to ensure the sustainable development of the city,in accordance with the planning and construction goals of the sponge city,study the construction technology facilities for sponge city suitable for Xianyang City The overall plan,and taking the demonstration area as an example,through the SWMM model simulation,analyze the effect of the sponge city construction and the feasibility of the construction plan.The specific conclusions are as follows:(1)According to the goals of the sponge city planning and construction,based on the analysis of the existing problems and needs in Xianyang City,the regional total annual runoff control target was determined to be 80%.Then,according to the topography,distribution of water system and the functional zoning of regional land planning,the drainage zone is determined,and then the control target is decomposed into 12 management units through the division model of “drainage zone-control unit-target decomposition”.(2)Through the land use planning and soil properties of Xianyang City,determine the appropriate sponge city construction facilities,and divide the four types of land types,such as buildings and sites,municipal roads,park green spaces and squares,and water bodies,and propose corresponding engineering design and construction plans to Therefore,the sponge facility construction plan is determined.In order to guarantee the landing of the sponge city,it proposes its non-engineering construction measures.(3)Take the demonstration area as an example to analyze the effect of sponge city construction.According to the "drainage zoning-control unit-target decomposition" model,the demonstration area is divided into 28 drainage zonings,and on the principle of maximizing the use of water resources,the drainage strategies of each zoning are divided into centralized lake surface surface collection,underground collection utilization and infiltration Three types of groundwater replenishment.Combined with the geological characteristics of the area,measures such as planting grass ditch,central green corridor,rainwater collection facility,rainwater garden and concentrated infiltration zone are adopted to plan and construct it.The model construction was completed through SWMM’s generalization of the demonstration area,the setting of hydrological and LID measure parameters.The simulation results show that the runoff of the demonstration area after the construction of the sponge city is 50835.5 m3,and the total runoff control rate is 85.47%,which meets the planning target.