Here you can download the most recent version of the reader, which is used in the lectures. See below for a short summary of all chapters.

Summary

Chapter 1. Backgrounds and specific aspects

The increasing interest in underground construction has resulted from a rise in more complex infrastructure and the increasing problems with space arrangement. The appreciation of the environment is also rising. The interest is greater than just putting large projects (infrastructure) underground. This chapter will focus on the main aspects involved in the use of the underground space. The history, technology, motives, functions and difficulties of underground constructions will be covered. The last section will shed some light on underground construction within The Netherlands.

Chapter 2. A strategic view and broad assessment of underground construction

The choice between constructing at surface level or in the underground is a difficult one. An integral approach in the decision making process is essential for finding the most suitable solution. This chapter will look at future scenarios and the role that underground space technology can play, followed by a broad assessment of underground construction. Finally some conclusions from a strategic study concerning the Dutch situation will be given.

Chapter 3. Influences of Geotechniques

The geological soil types and the history of loading influence the characteristics of soil and are therefore very important to the design and construction of subsurface constructions. Remember that geotechnical influences should always be taken into account when considering subsoil constructions. The changes that take place due to activities in the subsoil can cause great damages to surrounding buildings. In this chapter we will look at several geotechnical aspects such as homogeneity, deformations, settlements, safety factors et cetera.

Chapter 4. Risks

Before risk analysis can take place it is necessary to understand the concept of risk. This chapter starts with this explanation and continues to risk management applied on underground constructions. For underground construction projects the risks are always larger than for similar above ground projects. An important question during the early project phases is: “Who should take the responsibility and thus the risks?”

Chapter 5. General construction methods

This chapter covers the general construction methods that are used in subsurface construction. In principle there are three types of underground structures: Cellar constructions, Tunnels and Caverns/cavities. Constructing these various structures can be done by numerous building methods which will be discussed in this chapter.

Chapter 6. Cellar constructions

A cellar construction is a structure with a limited physical range. Methods that can be used to create a (deep) cellar construction are discussed in the following sections. Some techniques used to create a cellar construction were already discussed in chapter 5 “General construction methods”.

Chapter 7. Tunnels built from ground level

Tunnels are line-shaped underground civil-technical structures for roads, railways and public transport. They can be built with the techniques discussed in chapter 5, such as the open building pit method, cut-and-cover method, and the pneumatic caisson method. Special techniques in this context are the bored tunnel method and the immersed tunnel method. In this chapter only open building pits will be discussed, for example the ‘cut and cover method’.

Chapter 8. Bored tunnels

Besides the construction methods from surface level and the immersed tunnel method, there is a third important technique for building tunnels, namely the shield method. This method is suitable for building in soft soil conditions, varying from limestone and clay to sand. The technique was invented by the French engineer Marc Isambard Brunel. It was first used to tunnel under the Thames in London, in the beginning of the nineteenth century. The shield is actually a cylinder of steel, which bores through the ground. In the front the ground is excavated, then the ground is transported to the back along the already built tunnel part. The actual tunnel is built inside the shield. This usually consists of prefabricated reinforced concrete segments, joined together with bolts. When the tunnel part inside the shield is completed, the shield is pressed forward by screw pumps attached to the previously completed tunnel section.

Chapter 9. Immersed tunnels

Immersing a tunnel is a method by which the tunnel elements are built in a construction dock and floated to their final destination, where they are immersed. It is a well developed field of study in The Netherlands. Almost all river crossing tunnels have been realised with this method (an exception in the Netherlands is the Velser tunnel). The immersed tunnel method is especially suitable for crossings of rivers and canals, but it does not have to be restricted to these, as one can read in this chapter. The hindrance is restricted to the dredging of the immersion trench, the transportation of the elements, and the immersing operation of the tunnel elements. An advantage of immersed tunnels compared to bored tunnels is that they are situated at a shallower depth. This means the sloped access roads are at shallower depth and the length of the entire tunnel can be much smaller.

Chapter 10. Open-trench constructions

When comparing direct costs, building of underground infrastructure is very expensive compared to building on ground level. Deepening is a compromise, in some cases this can be a good alternative. Over recent years new construction methods have been developed for deepening (rail) roads, mainly to reduce the building costs. A number of disciplines are, more or less, in the experimental stage, like membrane solutions, the U-polder, the V-polder and the TOMAS method.

Chapter 11. Trenchless technology

In the past every cable or main could only be placed by continuous, open-cut excavation. This method gives a lot of disturbance directly above and next to the hole. In present times the consequences for the environment around these open cuts have become unacceptable. The trenchless technologies offer an alternative for these situations in many cases. Since the 1950s, it has been relatively common to use jacking and rotary boring methods to bore horizontal holes to install pipeline and utility crossings under rights-of-way such as highways and railroads. The last decades the use of these techniques in the Netherlands expanded rapidly. The goal of this chapter is to give an introduction to the trenchless technologies. It shows when and where it can be used and it gives the principles of the different techniques. Furthermore, the advantages, disadvantages and important parameters will be discussed. Also the reparation methods, the open-front technology, closed front drillings and the horizontal directional drilling methods will be discussed.