Study On Floor Area Ratio’s "Interval Form" In Residential Group Under The Influence Of Residential Quarter’s Public Welfare Facilities

District level public facilities is very important to improve the residential livingenvironment and living quality. The controlled detailed planning (hereinafter referredto as the "planning") plays an important role in cell level public welfare facilities,however, configuration and volume of public facilities for public welfare index indexmismatch problems in many residential areas. The volume of the core as the regulatorydevelopment intensity index, which should be an interval value. The volume of "value"to explore the volume in order to safeguard the public interests as the core target rate"elastic range or interval". In this paper, the volume of "range" control method is basedon the research results, by constructing the mathematical model, to explore the idealstate (assuming the distribution of different groups living an ideal living area ishomogeneous, equal, and the residents demand for public facilities are composed ofsmall internal resolve itself, cross to city or district level, cross region admission inreality not considered reasonable rate) volume matching criteria and district levelpublic facilities built, to scientifically determine the group living volume rate on theindex, the lower limit.The focus of this paper is to investigate the group living volume rate range controlmethod. This paper selected the kindergarten, primary school, health stations threefactors as the group living in the volume of the main factors affecting the cell level,and therefore constructs a theory model of volume rate range of single factor under theinfluence:"kindergarten--the volume of" model, the lower limit model is theminimum class independent land in matching number the function and childcare services within a radius of the smallest population, an upper bound model is with thelargest population in children when the minimum average land area of the relatedfunction, range interval (0.6,5.4);"primary school--the volume of" model, the lowerlimit model is the smallest class and service radius of minimum living populationshould be primary school the number of matched primary school related function, anupper bound model is the smallest average and maximum population when pupils inPrimary School of the land area of the related function, range interval (1.0,5.8);"Health Station--the volume of" model, the lower limit model is a function associatedwith a minimum total building sanitary station area, an upper bound model is afunction associated with the maximum total building sanitary station area, rangeinterval (0.2,5.9). Therefore, the volume of residential group comprehensive rangeinterval (1.0,5.4). Through the comparative analysis of typical residential high-techzones in Xi’an city as the prerequisite, range control volume rate is to strengthen theresidential planning of public facilities in the reasonable service radius layout; at thesame time, the lower level programming, volume rate variance index and publicinterest factors should also play a role; in addition, the residential developmentsuggestions of the future with appropriate size (large or middle scale is appropriate) forthe overall planning, do the facility layout of justice and equality.