In the field of construction and particularly in civil engineering, organic materials are essentially perceived as bonding additives. Whether we are talking about bitumens for road surfacing, polymers for formulating products for repair and structural gluing or admixtures for a more compact concrete, all these products are intended for realizations where we want to ensure the cohesion of granular groups.

This is in fact the primary role assigned to this class of materials, but we must not forget that there are other fields where plastic materials have been developed successfully, particularly sealing, environmental protection and engineering geology in general. Here, we enter into the field of manufactured products where the term organic material takes on its fullest meaning. We may also note in passing that industrial wood, the discovery of which is of course not recent, but whose industrial development is changing rapidly, falls under this second category.

The presentation of organic materials used in civil engineering therefore compels us to study these two aspects in depth. As such, we will deal with these in the first few chapters, but we will not place our main focus on them, as our study is based on a physico-chemical approach, as suggested by the subtitle of this book. This point calls for a few explanations.

In a construction project, the designer expects from the materials that he intends to use a set of properties, in particular:

• mechanical properties, such as a certain compressive strength for the realization of a...