This is the 2nd edition of one of the most comprehensive accounts of debris flow, describing both theoretical and applied aspects. In the first part, the fundamental mechanical characteristics are discussed, including flow characteristics, type classification, mechanics, occurrence and development, fully developed flow, and deposition processes. Th

Tamotsu Takahashi (Kyoto, 1939) graduated as a Master in Civil Engineering at Kyoto University in 1965. From 1965 to 1967, he then worked as a research assistant at the Disaster Prevention Research Institute (DPRI) of the same university and, after a year in the Civil Engineering Department as a lecturer, he returned in 1968 to the DPRI as an associate professor. With his research on flood flow dynamics in river channels, he obtained the doctoral degree in 1972. After this, he worked as a post-doctoral fellow at Lincoln College, New Zealand, where he investigated miscellaneous problems that were associated with braided rivers. Upon returning to DPRI in Japan, he put importance on the study of sediment runoff problems that were involved with debris flow and bed load on very steep slope channels. Consequently, in 1982, he was awarded a full professorship for a newly founded research section on the investigation of anti-flood hazards systems. He then added slightly more themes to his portfolio and extended his research to the water flooding and sediment problems in urban areas. From 1992 he moved to the research section on the investigation of sedimentation problems.

After his retirement in 2003, he continued working on debris flow and sediment runoff problems as a professor emeritus at Kyoto University. From 1995 to 1997 he served as the director of DPRI and during this appointment, he has reorganized the entire DPRI and has thoroughly promoted the scientific investigation of the Great Hanshin Earthquake which took place in Kobe in 1995 as the director of DPRI and the head of the Japanese Group for the Study of Natural Disaster Science. He is now working for the foundation 'Association for Disaster Prevention Research' as the chief director.

Professor Takahashi has authored numerous papers and held many invited keynote lectures. He also received several awards for his outstanding work from the Japan Society of Civil Engineers and from the Japan Society of Erosion Control Engineering. His successful book 'Debris Flow', published in 1991 by A.A. Balkema Publishers in the IAHR monograph series was the first systematic approach to the subject and is still frequently referred to. The original Japanese language version of this current new and extended edition was received very well and the author was awarded the Publishing Culture Prize from the Japan Society of Civil Engineers in 2004 for it. He was also awarded the Akagi Prize in 2008 for his outstanding contributions to the prevention and mitigation of debris flow disasters.

Preface
Preface to the first English edition
Preface to the second English edition
About the author

1 What is debris flow?
1.1 Various sediment moving phenomena
1.2 Definition of debris flow
1.3 Classification and characteristics of debris flows
1.3.1 Stony-type debris flow
1.3.2 Turbulent-muddy-type debris flow
1.3.3 Viscous debris flow
1.4 The significance of the mechanical classification of debris flows
1.5 Classifications based on other view points

2 Models for mechanics of flow
2.1 Models for solids and fluid mixture as the multi-phase flow
2.2 Single-phase continuum models
2.2.1 Visco-plastic fluid model
2.2.2 Dilatant fluid model
2.3 Two-phase continuum models (mixture theory)
2.3.1 Stress equilibrium equations
2.3.2 Coulomb mixture theory (Quasi-static debris flow)
2.4 Theory for subaerial rapid granular flows
2.4.1 Particle collision stress
2.4.2 Kinetic stress
2.4.3 Skeletal stresses
2.4.4 Constitutive relations
2.4.5 Application of the theory to dry granular flow
2.4.6 Comparison with other constitutive relations for inertial range
2.5 Mechanical classification of debris flows revisited based on the theory for granular flows
2.6 The mechanism of inertial debris flows
2.6.1 The supplementary explanation of mature stony debris flow
2.6.2 Immature debris flow
2.6.3 Turbulent-muddy debris flow
2.7 Generalized theory for inertial debris flows
2.7.1 Theoretical considerations
2.7.2 Verification by experimental data
2.7.3 Approximate solutions for solids concentration and resistance to flow
2.8 Newtonian fluid model for viscous debris flow
2.8.1 Theoretical considerations
2.8.2 Verification by experiments
2.9 Equilibrium sediment discharge in inertial debris flows

3 Initiation, development and declination of debris flow
3.1 Initiation and development of debris flow due to gully bed erosion
3.1.1 The formation of incipient debris flow by the effects of surface water runoff
3.1.2 The development and decline of stony debris flow on sediment bed
3.1.3 Verification of the theory by experiments
3.2 Landslide-induced debris flow
3.2.1 Mechanism of shallow landslides induced by severe rainfall
3.2.2 Debris avalanche
3.2.3 Model for the transformation into debris flow
3.2.4 Mathematical model for the one-dimensional motion of a deformable earth block with the liquefied layer
3.2.5 Numerical simulation of earth block and debris flow motions across a three-dimensional terrain
3.3 Debris flow and flood flow induced by the collapse of a natural dam
3.3.1 Formative conditions and shapes of a natural dam
3.3.2 Life span of a natural dam
3.3.3 Failure in entire channel width and the resulting debris flow
3.3.4 Prediction of debris flow/flood flow induced by the overflow in partial width

4 Characteristics of fully-developed debris flow
4.1 Translation of debris flow surge and the shape of the snout
4.1.1 The case of stony-type debris flow
4.1.2 The case of viscous-type debris flow
4.2 Boulder accumulation at the forefront of stony debris flow
4.2.1 Various concepts for the mechanism
4.2.2 The theory of Takahashi (1980)
4.3 Ability to transport large boulders
4.4 The causes of intermittency
4.5 Debris flow around a bend
4.6 Routing of debris flow in the transferring reach
4.6.1 Kinematic wave method
4.6.2 Dynamic wave method

5 Processes and geomorphology of deposition
5.1 One-dimensional stoppage/depositing processes of stony debris flow
5.1.1 The arrival distance at the sudden change in channel slope
5.1.2 Topography of deposit formed at a sudden slope change
5.1.3 Numerical simulation of depositing process
5.2 One-dimensional depositing process of turbulent muddy debris flow
5.3 Formation of a debris flow fan
5.3.1 Description of the experimental results for stony debris flow and empirical presentations of the feature of a debris flow fan
5.3.2 Numerical simulation of fan formation process and its verification
5.3.3 Numerical simulation of fan formation by turbulent debris flow
5.4 Particle size distribution in the fan formed by stony debris flow
5.4.1 General situations found in the field and experimental data
5.4.2 Mathematical model for the particle size distributions
5.5 Erosion and deformation of a debris flow fan
5.5.1 Experiments for the process of erosion
5.5.2 Model and its verification for the fan comprised of uniform material
5.5.3 Model and its verification for the fan comprised of heterogeneous material

6 Sediment runoff models that include debris flow processes
6.1 The viewpoints for the process-based modeling of sedi…