| At the beginning of the 21st century,China entered into a phase of rapid urbanization and the urban population increased exponentially,resulting in saturated urban population density,traffic congestion and a severe shortage of urban space resources.Underground space development can effectively alleviate the shortage of urban space resources,but because underground space is a new type of national resource,it is irreversible and cannot be recycled once developed.Therefore,the suitability evaluation of underground space development is an important part of rational and orderly development,and is also a necessary precondition for scientific planning of national land space.This paper is based on the sub-topic of "2017 Provincial Geological Survey Project of Shanxi Provincial Department of Land and Resources"(SXZDF20170820): "Urban Geological Survey Project of Xiahe Modern Industrial Zone in Shanxi Transformation and Comprehensive Reform Demonstration Zone".Based on the field survey,the evaluation index system of shallow(0-10m),middle(10-30m)and deep(30-50m)layers is constructed according to the topography,engineering geological conditions,hydrogeological conditions,environmental geology,seismic geology and surface development status at different depths in the study area.In order to avoid the shortcomings of the traditional evaluation model with insufficient objectivity,this paper proposes the combination of triangular fuzzy hierarchical analysis and genetic algorithm(TFN-AHP-GA)to calculate and assign the weights of each influence factor except the current situation of surface development,and obtain the preliminary judgment results of the suitability of the study area by using the spatial calculation function of the software,and then consider the influence of the current situation of surface development on the suitability of each stratum in the study area,and use the Then,considering the influence of the current situation of surface development on the suitability of each layer in the study area,the initial judgment results were modified using the judgment matrix,and the final evaluation results of the suitability zoning of underground space development in the study area were obtained for three layers,and the following conclusions were obtained.The results of the suitability evaluation of shallow underground space development in the study area: the area of poor suitability is 61.7km2,accounting for 15.97%;the area of poor suitability is 196.87km2,accounting for 50.97%;the area of good suitability is 6.82km2,accounting for 1.77%;the area of good suitability is 120.84km2,accounting for 31.29%.The development of shallow underground space is dominated by poor suitability(50.97%)and good suitability(31.29%),and the overall development is difficult and saturated,so the development should be carried out with reasonable and orderly planning to avoid wasting space resources.The main factors limiting the development of shallow underground space are the current status of surface development,groundwater corrosion and sandy soil liquefaction.The results of the suitability evaluation of the middle underground space development in the study area are as follows: the area of poor suitability is 1.79km2,accounting for 0.46%;the area of poor suitability is 168.79km2,accounting for 43.70%;the area of good suitability is 191.58km2,accounting for 49.60%;the area of good suitability is 24.01km2,accounting for 6.22%.The development of middle underground space is dominated by poor suitability(43.70%)and good suitability(49.60%),and the evaluation of suitability of this level of underground space development in the study area is good.The main factors limiting the development of middle underground space are the corrosiveness of groundwater,sand liquefaction and the current situation of surface development(if the surface is a railroad and a high-rise building,the development and use of the underground 0-50 m is prohibited),therefore,when developing the middle and shallow underground space,it is necessary to use measures such as vibrating and punching,compacting and compacting piles to improve the density of the foundation soil,and also take water control measures to reduce the corrosiveness of SO42-,H+ and other media in groundwater.Corrosion.The evaluation results of the suitability of deep underground space development in the study area are as follows: the area of poor suitability is 22.13km2,accounting for 5.73%;the area of poor suitability is 172.16km2,accounting for 44.57%;the area of good suitability is190.96km2,accounting for 49.44%;the area of good suitability is 0.98km2,accounting for0.25%.Deep underground space development is dominated by poor suitability(44.57%)and good suitability(49.44%),and the suitability evaluation results of this level of underground space development in the study area are good.The main factors that restrict the development of deep underground space are the corrosiveness of groundwater and the current situation of surface development(if the surface is a railroad and a high-rise building,the development and use of its underground 0-50 m is prohibited),so when developing the deep layer,water control measures and foundation reinforcement measures should be taken.At present,the degree of underground space development in Shanxi Xiaohe Modern Industrial Park is still at a relatively low level.This study explores the construction method of the evaluation index system,proposes to use the TFN-AHP-GA model to calculate the evaluation index weights,and obtains the evaluation results of the adaptability of underground space development in three levels of the study area through the spatial analysis function of GIS software and the calculation of judgment matrix,which provides information reference and planning for the underground space development in the study area.It also provides a reference for the development and construction of underground space in plain areas with similar geological conditions as the study area. |
PDF Full Text Request