Geotechnics is the application of scientific methods and engineering principles to the acquisition, interpretation, and use of knowledge of materials of the Earth's crust and earth materials for the solution of engineering problems and the design of engineering works. It is the applied science of predicting the behavior of the Earth, its various materials and processes towards making the Earth more suitable for human activities and development.
LS-DYNA is an advanced general-purpose multiphysics simulation software package developed by the Livermore Software Technology Corporation (LSTC). While the package continues to contain more and more possibilities for the calculation of many complex, real world problems, its origins and core-competency lie in highly nonlinear transient dynamic finite element analysis (FEA) using explicit time integration. LS-DYNA is used by the automobile, aerospace, construction and civil engineering, military, manufacturing, and bioengineering industries.
Slope stability refers to the condition of inclined soil or rock slopes to withstand or undergo movement. The stability condition of slopes is a subject of study and research in soil mechanics, geotechnical engineering and engineering geology. Slope stability analyses include static and dynamic, analytical or empirical methods to evaluate the stability of earth and rock-fill dams, embankments, excavated slopes, and natural slopes in soil and rock. The analyses are generally aimed at understanding the causes of an occurred slope failure, or the factors that can potentially trigger a slope movement, resulting in a landslide, as well as at preventing the initiation of such movement, slowing it down or arresting it through mitigation countermeasures.
Discontinuous deformation analysis (DDA) is a type of discrete element method (DEM) originally proposed by Shi in 1988. DDA is somewhat similar to the finite element method for solving stress-displacement problems, but accounts for the interaction of independent particles (blocks) along discontinuities in fractured and jointed rock masses. DDA is typically formulated as a work-energy method, and can be derived using the principle of minimum potential energy or by using Hamilton's principle. Once the equations of motion are discretized, a step-wise linear time marching scheme in the Newmark family is used for the solution of the equations of motion. The relation between adjacent blocks is governed by equations of contact interpenetration and accounts for friction. DDA adopts a stepwise approach to solve for the large displacements that accompany discontinuous movements between blocks. The blocks are said to be "simply deformable". Since the method accounts for the inertial forces of the blocks' mass, it can be used to solve the full dynamic problem of block motion.
UTEXAS is a slope stability analysis program written by Stephen G. Wright of the University of Texas at Austin. The program is used in the field of civil engineering to analyze levees, earth dams, natural slopes, and anywhere there is concern for mass wasting. UTEXAS finds the factor of safety for the slope and the critical failure surface. Recently the software was used to help determine the reasons behind the failure of I-walls during Hurricane Katrina.
SEEP2D is a 2D seepage analysis program written by Dr. Fred Tracy of the United States Army Corps of Engineers. The program is used to analyze water seepage, typically through dams and levees or under sheet piles. "The model is internationally known in the engineering community as a model for complicated seepage analysis of dams and levees." It has been shown to have acceptable accuracy compared with experimental results.
Finite element model updating is the process of ensuring that finite element analysis results in models that better reflect the measured data than the initial models. It is part of verification and validation of numerical models.
NEi Software, founded as Noran Engineering, Inc. in 1991, is an engineering software company that develops, publishes and promotes FEA software programs including its flagship product NEi Nastran. The FEA algorithms allow engineers to analyze how a structure will behave under a variety of conditions. The types of analysis include linear and nonlinear stress, dynamic, and heat transfer analysis. MCT, PPFA, dynamic design analysis method, optimization, fatigue, CFD and event simulation are just some of the specialized types of analysis supported by the company.
Z88 is a software package for the finite element method (FEM) and topology optimization. A team led by Frank Rieg at the University of Bayreuth started development in 1985 and now the software is used by several universities, as well as small and medium-sized enterprises. Z88 is capable of calculating two and three dimensional element types with a linear approach. The software package contains several solvers and two post-processors and is available for Microsoft Windows, Mac OS X and Unix/Linux computers in 32-bit and 64-bit versions. Benchmark tests conducted in 2007 showed a performance on par with commercial software.
The Bridge Software Institute is headquartered at the University of Florida (UF) in Gainesville, Florida. It was established in January 2000 to oversee the development of bridge related software products at UF. Today, Bridge Software Institute has a leadership position in the bridge software industry and Bridge Software Institute products are used by engineers nationwide, both in state Departments of Transportation and leading private consulting firms. Bridge Software Institute software is also used for the analysis of bridges in various countries by engineers around the world.
Slope stability analysis is performed to assess the safe design of a human-made or natural slopes and the equilibrium conditions. Slope stability is the resistance of inclined surface to failure by sliding or collapsing. The main objectives of slope stability analysis are finding endangered areas, investigation of potential failure mechanisms, determination of the slope sensitivity to different triggering mechanisms, designing of optimal slopes with regard to safety, reliability and economics, designing possible remedial measures, e.g. barriers and stabilization.
SVFLUX is a finite element seepage analysis program developed by SoilVision Systems Ltd.. The software is designed to analyze both saturated and unsaturated flow through the ground through the solving of Richard's equation. The program is used in the fields of civil engineering and hydrology in order to analyze seepage and groundwater regional flow. The software is used for the calculation of flow rates, pore-water pressures, and pumping rates associated with regional groundwater flow. The software can be coupled with CHEMFLUX in order to calculate diffusion, advection, and decay rates or with SVHEAT in order to calculate thermal gradients and freeze/thaw fronts.
FEBio(Finite Elements for Biomechanics) is a software package for finite element analysis and was specifically designed for applications in biomechanics and bioengineering. It was developed in collaboration with research groups from the University of Utah and Columbia University (MBL).
A finite element limit analysis (FELA) uses optimisation techniques to directly compute the upper or lower bound plastic collapse load for a mechanical system rather than time stepping to a collapse load, as might be undertaken with conventional non-linear finite element techniques. The problem may be formulated in either a kinematic or equilibrium form.
Sarada Kanta Sarma is a geotechnical engineer, emeritus reader of engineering seismology and senior research investigator at Imperial College London. He has developed a method of seismic slope stability analysis which is named after him, the Sarma method.
VisualFEA is a finite element analysis program running on MS Windows and Mac OS X platforms. The program is being developed and distributed by Intuition Software, Inc. in South Korea, and is used chiefly for structural and geotechnical analysis. The strongest point of the program is its intuitive and user-friendly usage based on graphical pre- and postprocessing capabilities. VisualFEA has educational functions for teaching and learning structural mechanics and finite element analysis through graphical simulation. Thus, this program is widely used in college courses related to structural mechanics and finite element method.
The Newmark's sliding block analysis method is an engineering that calculates permanent displacements of soil slopes during seismic loading. Newmark analysis does not calculate actual displacement, but rather is an index value that can be used to provide an indication of the structures likelihood of failure during a seismic event. It is also simply called Newmark's analysis or Sliding block method of slope stability analysis.
The Sarma method is a method used primarily to assess the stability of soil slopes under seismic conditions. Using appropriate assumptions the method can also be employed for static slope stability analysis. It was proposed by Sarada K. Sarma in the early 1970s as an improvement over the other conventional methods of analysis which had adopted numerous simplifying assumptions.
David Malcolm Potts is a professor of Analytical Soil Mechanics at Imperial College London and the head of the Geotechnics Section at Imperial College. He has been a member of the academic staff at Imperial College since 1979, responsible for teaching the use of analytical methods in geomechanics and the design of slopes and earth retaining structures, both at undergraduate and postgraduate levels.
