File Download
  Links for fulltext
     (May Require Subscription)
Supplementary

postgraduate thesis: Numerical modeling of landslide-induced waves and their effects on downstream structures

TitleNumerical modeling of landslide-induced waves and their effects on downstream structures
Authors
Advisors
Advisor(s):Tham, LG
Issue Date2012
PublisherThe University of Hong Kong (Pokfulam, Hong Kong)
Citation
Liu, X. [刘霞]. (2012). Numerical modeling of landslide-induced waves and their effects on downstream structures. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4819941
AbstractImpulse waves in reservoirs, lakes, bays and oceans may be generated by landslides. The resulting impulse waves can propagate and cause disaster to the downstream. Some studies are carried out to investigate such phenomenon but most of them were based on either experimental observations or empirical/semiempirical relationships in simulating the waves generated by landslides. Therefore, the fundamental mechanism of such hazard is not got fully understood (complex motions of landslides with arbitrary geometry and interactions of fluid with landslides or shorelines). In addition, the effects of landslide-induced waves on downstream structures are rarely reported. Therefore, it appears necessary that the coupling numerical model is developed to simulate landslide-induced waves and to investigate generated wave characteristics. Furthermore, their effects on downstream structures should be investigated for mitigating hazard, such as the estimations of wave run-up, rundown and wave overtopping. This thesis presents the numerical modeling of landslide-induced waves and their effects on the downstream structures based on the computational fluid dynamics (CFD) package FLUENT. As there is no existing module to simulate water waves, the redevelopment of FLUENT by the user defined function (UDF) is necessary. For the problem of landslide-induced wave, two simplified numerical models are developed, including piston-type model and inlet boundary-type model. These two numerical models can rapidly assess the landslide-induced waves but be appropriate for the simple cases, such as a vertical wall moving horizontally or slump-type landslide whose particle velocities and free surface displacements at the inlet boundary are known. In order to expand the available range of numerical modeling, the block models aiming for rockslide are developed to investigate landslide-induced waves. Four categories of landslides are considered, such as horizontal landslide, vertical landslide, subaerial landslide and submarine landslide. Except of horizontal landslide, the coupled block model is employed to investigate water waves generated by vertical, subaerial and submarine landslides. The coupling is based on an iterative procedure enforcing the principle of the dynamic equilibrium of the fluid, the slide and their interfaces, and the interaction between landslide and fluid are considered. The wave characteristics generated by above-mentioned different types of landslides are investigated and discussed. For their effects of landslide-induced wave on downstream structures, the focuses of numerical modeling are the run-up and rundown of waves generated by subaerial and submarine landslides and wave overtopping on the downstream structures. The detailed numerical modeling illustrates that the present models can predict fairly well landslide-induced waves and their effects on downstream structures. The results of parametric study indicate that slide volume and impact Froude number ( v / gh ) play important roles on generated wave characteristics. The wave characteristics, propagation distance and geometric characteristics of seaward structural wall (slope and crest freeboard) are major factors in determining the characteristics of wave run-up, rundown and overtopping. Several useful prediction relationships are provided.
DegreeDoctor of Philosophy
SubjectWater waves - Mathematical models.
Landslides.
Dept/ProgramCivil Engineering

 

DC FieldValueLanguage
dc.contributor.advisorTham, LG-
dc.contributor.authorLiu, Xia-
dc.contributor.author刘霞-
dc.date.issued2012-
dc.identifier.citationLiu, X. [刘霞]. (2012). Numerical modeling of landslide-induced waves and their effects on downstream structures. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4819941-
dc.description.abstractImpulse waves in reservoirs, lakes, bays and oceans may be generated by landslides. The resulting impulse waves can propagate and cause disaster to the downstream. Some studies are carried out to investigate such phenomenon but most of them were based on either experimental observations or empirical/semiempirical relationships in simulating the waves generated by landslides. Therefore, the fundamental mechanism of such hazard is not got fully understood (complex motions of landslides with arbitrary geometry and interactions of fluid with landslides or shorelines). In addition, the effects of landslide-induced waves on downstream structures are rarely reported. Therefore, it appears necessary that the coupling numerical model is developed to simulate landslide-induced waves and to investigate generated wave characteristics. Furthermore, their effects on downstream structures should be investigated for mitigating hazard, such as the estimations of wave run-up, rundown and wave overtopping. This thesis presents the numerical modeling of landslide-induced waves and their effects on the downstream structures based on the computational fluid dynamics (CFD) package FLUENT. As there is no existing module to simulate water waves, the redevelopment of FLUENT by the user defined function (UDF) is necessary. For the problem of landslide-induced wave, two simplified numerical models are developed, including piston-type model and inlet boundary-type model. These two numerical models can rapidly assess the landslide-induced waves but be appropriate for the simple cases, such as a vertical wall moving horizontally or slump-type landslide whose particle velocities and free surface displacements at the inlet boundary are known. In order to expand the available range of numerical modeling, the block models aiming for rockslide are developed to investigate landslide-induced waves. Four categories of landslides are considered, such as horizontal landslide, vertical landslide, subaerial landslide and submarine landslide. Except of horizontal landslide, the coupled block model is employed to investigate water waves generated by vertical, subaerial and submarine landslides. The coupling is based on an iterative procedure enforcing the principle of the dynamic equilibrium of the fluid, the slide and their interfaces, and the interaction between landslide and fluid are considered. The wave characteristics generated by above-mentioned different types of landslides are investigated and discussed. For their effects of landslide-induced wave on downstream structures, the focuses of numerical modeling are the run-up and rundown of waves generated by subaerial and submarine landslides and wave overtopping on the downstream structures. The detailed numerical modeling illustrates that the present models can predict fairly well landslide-induced waves and their effects on downstream structures. The results of parametric study indicate that slide volume and impact Froude number ( v / gh ) play important roles on generated wave characteristics. The wave characteristics, propagation distance and geometric characteristics of seaward structural wall (slope and crest freeboard) are major factors in determining the characteristics of wave run-up, rundown and overtopping. Several useful prediction relationships are provided.-
dc.languageeng-
dc.publisherThe University of Hong Kong (Pokfulam, Hong Kong)-
dc.relation.ispartofHKU Theses Online (HKUTO)-
dc.rightsThe author retains all proprietary rights, (such as patent rights) and the right to use in future works.-
dc.rightsCreative Commons: Attribution 3.0 Hong Kong License-
dc.source.urihttp://hub.hku.hk/bib/B48199412-
dc.subject.lcshWater waves - Mathematical models.-
dc.subject.lcshLandslides.-
dc.titleNumerical modeling of landslide-induced waves and their effects on downstream structures-
dc.typePG_Thesis-
dc.identifier.hkulb4819941-
dc.description.thesisnameDoctor of Philosophy-
dc.description.thesislevelDoctoral-
dc.description.thesisdisciplineCivil Engineering-
dc.description.naturepublished_or_final_version-
dc.identifier.doi10.5353/th_b4819941-
dc.date.hkucongregation2012-

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats