The Functional Evaluation Of Huanhuaxi Disaster-prevention Parks

Chengdu suffered extreme weather and earthquakes in these years,which will cause negative influences on safe environment on urban areas.Since the “5.12” earthquake,the government of Chengdu focused on the construction of the disaster-prevention system that consists mainly of city parks in central areas.The sitting of park and the functional design are two key factors which will influence these parks' disaster-prevention effects,so it is important to strengthen these two factors when we research on parks' disaster-prevention function.The central city parks of Chengdu have remoulded its' disaster-prevention planing,but these central parks still cannot satisfy dewellers' needs in terms of saking for refuge after human-made or nature disaster.In order to strengthen these parks' disaster-prevention function,the authority has published relevant official documents called <Chengdu green space planning 2006-2020> which proposed to build a park system around huanhuaxi.However,this plan has not yet carrying out.Because of this,this resaech choose three parks(Huanhuaxi park,Wenhua parks and Baihuatan park)mentioned in the official document as a research example,the main research content,calculation results and conclusion as follows:(1)The sitting of disaster-prevention huanhuaxi parks evaluationFirstly,in this part,we elected 12 factors relevant to disaster-prevention parks as evaculation indexes according <city anti-seismic planning regulation> and the site investigation.Secondly,the combination Entropy Value Method and Analytic Hierarchy Process as a new method named hierarchy-entropy combination assigning method which can combine the objective and subjective evaluation to comfirm weights.Finnaly,we use TOPSIS method to evaluate three candidate parks.The evaluation results are 0.69148(P1)?0.36163(P3)?0.33821(P2)respectly,which proves that Huanhuaxi parks are the best,and then Baihutan park and wenhua park.(2)The evaluation of Huanhuxai parks design in terms of the disaster-preventionIn this part,the author focuses on the evaluation of parks' disaster-prevention design,the research is based on the site investigation and <disaster-prevention places design in urban and rural area > to create evaluation system.The evaluation of park's disaster-prevention design is the aim in this part,so this factor is a key and put it as first level.The space palnning,landscape factors and parks services are at the second level in this system,and there are 15 revelant factors at third level.We input these factors in the yaahp10.3,where we build evaluation system,calculation result and etc.The calculation results is 0.5573(P1),0.1760(P2)and 0.2667(P3),which proves that Huanhuaxi parks are best programme in this part,then Baihutan park and wenhua park.(3)The upgrade design in disaster-preventionBased on the site investigation and evaluation results,the problems in terms of sitting planning and functional design of huanhuaxi disaster-prevention parks are concluded.This part is upgrade design aimed at these problems.The content of the upgrade designs include the increase of green spaces between three parks and integration parks and green spaces into a new green park system to ease negative envriomental influences,switching space resources from the normal to the special when meeting human-made or nature disasters,and the use of landscape designs to strengthen the disaster-prevention function in three parks.The design results are that huanhuaxi parks is planned as the mixed-fucntion shelter park,Baihuatan park and Wenhua park are planned as single-shelter park.