The Research On The Construction Of Desheng North Road In Yueyang Based On The Concept Of Sponge City

The road traffic network will bring about a high degree of accessibility and distribution function to the city,but at the same time,it will lead to an increase in the proportion of surface impermeable areas.The problem of urban flooding and water pollution is increasingly prominent,the traditional road drainage system can not meet the needs of urban development.Sponge city road can effectively solve the problem of road rainwater discharge and improve the urban road hydrology environment.Therefore,the research of road construction based on the concept of sponge city is very necessary.The paper firstly summarizes the research progress of sponge city at home and abroad,analyzes the relationship between sponge city road system and low impact development,and summarizes the application scope of low impact development facilities in urban roads.According to the natural geography of Yueyang City,the rainfall runoff of this area was analyzed,and the original storm intensity formula was improved based on the measured value of the storm intensity collected by the meteorological department of Yueyang City.The corresponding indicators such as the integrated rainfall runoff coefficient and the annual runoff total of 70%are calculated.The design and storage volume of the low-impact development facilities is 369.18 m3 when the annual runoff total control rate is 70%.The actual storage capacity of the green space is 403.18 m3,which meets the requirement of 70%annual total runoff control rate when the designed rainfall of Yueyang City in the construction of the sponge city is 18.5 mm.Drawing on the relevant engineering experience at home and abroad,the overall planning and design plan for the sponge city of Desheng North Road in Yueyang City was proposed.And the supporting facilities such as the gap edge curb,the energy-saving sedimentation well,the plant grass ditch and the overflow rainwater well were designed.The structural layers are improved and optimized to promote rainwater infiltration and prolong the residence time of rainwater in the grassing ditch.It is proposed that the disposal method of physical engineering road rainwater is:the rainwater after the seepage saturation of the motorway and the permeable walkway flows through the curbstone gap to the energy-dissipating sedimentation well,and the rainwater is initially intercepted and filtered by the sedimentation well,and then,the grassland is infiltrated and the second interception is filtered by the pebbles around the overflow well and finally flows to the municipal rainwater pipe network to obtain cleaner rainwater.Applying the storm water management model(SWMM)to evaluate the rainwater runoff effect of the sponge city road construction in Desheng North Road.The time of peak,peak period runoff and total runoff in the three states of undeveloped,traditional roads and sponge urban roads were compared.The results show that compared with the traditional roads,the sponge urban road has better runoff control effect and is more beneficial to protect the hydrological ecological environment of urban roads.The research results can provide reference for the application of the sponge city concept in municipal roads.