现在世界人口已过50亿,2000年将达到60亿,2020年将达到80亿,趋向饱和。随着工业化的进程,人口大量向城市集中,一八八○年为世界人口的2.5%,经过20年膨胀为42.2%,预测2000年为51.3%。我国现在城市人口为全国人口的20.6%,预计2000年将达到4亿多,占32%。由于人口不断增加,给城市建设和发展带来许多困难和矛盾,如用地紧张,能源短缺,环境污染日趋严重等等。因此,开发利用地下空间,在世界各国越来越受重视,向地下要地皮,要环境,要能源已形成了一股“地下热”。 Now that the world’s population has passed 5 billion, it will reach 6 billion in 2000, and it will reach 8 billion by 2020, and it will become saturated. With the process of industrialization, a large number of people are concentrated in cities. In 1880, it was 2.5% of the world’s population. After 20 years, it expanded to 42.2%, and in 2000, it was predicted to be 51.3%. China’s urban population is now 20.6% of the country’s population. It is expected that it will reach 400 million, or 32%, in 2000. As the population continues to increase, it brings many difficulties and contradictions to the construction and development of the cities, such as the shortage of land, energy shortages, and increasingly serious environmental pollution. Therefore, the development and utilization of underground space has attracted increasing attention in all countries of the world, and it has created a “subterranean heat” for the environment and energy resources.