Geotechnics Of Organic Soils And Peat

Peat and organic soils commonly occur as extremely soft, wet, unconsolidated surficial deposits that are an integral part of wetland systems. These types of soils can give rise to geotechnical problems in the area of sampling, settlement, stability, in situ testing, stabilisation and construction. There is therefore a tendency to either avoid build

Peatlands are formed in limited areas and have significant effects on our planet. As a result of their use peatlands are continually shrinking on a daily basis. This edited book, Peat, is intended to provide an overview of different perspectives of peat material in relevant disciplines. We hope that this book will contribute to the expectations and needs of all relevant disciplines that share their findings for future research.

More and more civil engineering constructions are being built on soft soils. As areas with better foundations are used up the necessity to be able to build structures on soft soils increases. The most troublesome of soft soils are organic soils due mainly to their high compressibility (much higher than in mineral soils), and also their very low shear strength. The large diversity of organic soils with respect to their origin as well as their properties make classification, testing, and engineering prediction of behaviour, very difficult. For this reason, engineers try, in general, to avoid constructing on deep layers of organic soils. If forced, by necessity, to do so, they manage with light structures e.g. embankments or low buildings. The authors of this book have been involved in a joint research project on the testing of embankments on organic soils. This was carried out in the North-Western part of Poland by the Swedish Geotechnical Institute and the Department of Geotechnics of Warsaw Agricultural University. The results of their research is presented in this new book and provides a valuable insight into this growing area in the field of engineering geology.

Reasonable estimates indicate that approximately a billion cubic meters of high water content soil-like wastes are produced annually worldwide, and a large portion of these are deposited hydraulically in diked impoundment areas, some of which are among the largest earth structures in the world. The major problems emanating from this disposal method are the difficulty in dewatering the wastes, their low strength and hydraulic conductivity, their high compressibility, their potential to contaminate the groundwater, the stability of the confining dikes, and the ultimate reclamation of the disturbed land. Following a brief explanation of how many of these wastes are generated, quantitative values for key engineering properties are summarized and compared for a wide variety of waste materials and some reference soils. Then, many concepts that have been applied with success will be presented together with the advantages each offers, the difficulties involved in using it, and the limitations in our knowledge. Discussed briefly will be state-of-practice developments in mathematical modeling, laboratory testing and associated interpretations, and material property formulations.