Abstract: In recent years, residential care resources in Beijing have increased rapidly. The supply of residential care resources, however, is still in shortage due to the increase of demand. To reach the "9064" policy goal proposed by the Beijing municipal government, which means that 4 percent of elderly population in Beijing will live in residential care facilities in 2020, about 90 thousand beds of residential care facilities are still needed. An efficient method for measuring accessibility is of crucial importance for the spatial planning of residential care resources. Among a range of methods to measure the spatial accessibility of facilities, the two- step floating catchment area method (2SFCA) is most widely used. But the 2SFCA does not take distance decay among catchment areas into account, and catchment size is constant for facilities with different sizes, which may reduce the accuracy of the assessment. This study uses an improved two-step floating catchment area method, including the addition of a distance-decay function and variable catchment sizes depending on the size of residential care facility, to assess the spatial accessibility to residential care resources in Beijing. Two scenarios are set for comparison. The first scenario was analyzed using one hour catchment area and the second scenario was analyzed using three different catchment areas based on the sizes of residential care facilities. In both scenarios the distance-decay function was taken into account. The results show that the measurement of three catchment areas is a more effective method than the one catchment area for measuring the spatial accessibility to residential care facilities in Beijing. A map of spatial accessibility was developed to show the distribution of shortage areas of residential care resources in Beijing. This map indicates that the geographic distribution of spatial accessibility to residential care facilities in Beijing is fairly uneven. The spatial accessibility is higher in the western part, the northern part and the northeastern part as compared to the southern part of the city. The spatial accessibility in the central part is still poor in spite of a considerable number of residential care facilities located in the central city. This is due to the great size of elderly population in the central area of Beijing. Because land for constructing new residential care facilities is in great shortage in the core area of the city, such facilities should be located outside of the area or in the suburbs to provide services for elderly population in the central city. The spatial accessibility in the southern part is generally poor and very uneven, so new residential care facilities should be located across the area and more focus should be given to areas with relatively poorer spatial accessibility. These recommendations are consistent with the "Special Planning of Residential Care Facility for the Elderly in Beijing" by the Beijing municipal government.

Key words: 2SFCA, Beijing, residential care facilities, spatial accessibility