SPECIAL FEATURE STORY ON “Challenges in Going Underground in Big Cities”

Abstract

The hearts of many large cities are already congested. City planners are looking for ways to accommodate more people and to supply their needs including means of transportation. High rise buildings, descriptively called “sky scrapers”, are common and going higher does not necessarily solve the problem. Increasing the number of people in a congested area severely overtaxes the infrastructure with no space to expand it. Enclosure by sub-urban development inhibits lateral development. The next place to look is underground. Already many buildings have basements, already there are many subways for pedestrians, for metros and for roads and in several cities these are inter-connected. However, if one digs a hole in the road one will encounter lots of utilities and as more metro lines are developed they cross each other and construction to shallow depths in developed urban areas becomes deeper encountering more obstructions and can be very expensive. This paper reviews some of the challenges that face planners and geotechnical engineers when considering how to strategically plan urban development in major cities by going deeper underground.