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At the beginning of the 16th century, the original inhabitants of Čachtice built a large complex of tunnels and cellars under the village, today called the Čachtice underground. The underground protected people from war conflicts, most recently during World War II, as anti-aircraft shelters. Over time, the underground lost its significance. The corridors were walled up, covered with rubble, and collapsed due to construction work. Later, a part of the underground was repaired, and historical events occurred in such a preserved part. Due to a lawsuit, the Čachtice underground was eventually closed to the public, and it was necessary to test the stability of the walls of the Čachtice underground. A 3D model of the underground was created, and three areas were identified in which numerical calculations were performed in Plaxis 2D software. The whole underground is located in loess soil. The Čachtice underground is stable if the conditions do not change diametrically. The calculated factors of safety support this assumption.

A hypoplastic approach to constitutive modelling was developed by Kolymbas 1996 considering a non-linear tensor function in the form of strain and stress rate. However, the implicit formulation of the hypoplastic model with indirect material parameters severely limits its applicability to real-world geotechnical problems. In many cases, the numerical analysis of geotechnical problems relies on simple elastoplastic constitutive models that cannot model a wide range of soil response aspects. One promising paradigm of constitutive modelling in geotechnics is hypoplasticity, but many of the hypoplastic models belong to advanced models. In the article, we present the simple hypoplastic model as an alternative to the widely used Mohr-Coulomb elastoplastic model.

The article focuses on the use of the meshfree numerical method in the field of slope stability computations. There are many meshfree implementations of numerical methods. The article shows the results obtained using the meshfree localized Petrov-Galerkin method (MLPG) – localized weak-form of the equilibrium equations with an often used elastoplastic material model based on Mohr-Coulomb (MC) yield criterion. The most important aspect of MLPG is that the discretization process uses a set of nodes instead of elements. Node position within the computational domain is not restricted by any prescribed relationship. The shape functions are constructed using just the set of nodes present in the simple shaped domain of influence. The benchmark slope stability numerical model was performed using the developed meshfree computer code and compared with conventional finite element (FEM) and limit equilibrium (LEM) codes. The results showed the ability of the implemented theoretical preliminaries to solve the geotechnical stability problems.

The article deals with the road pavement surface morphology objectification in term of the surface unevenness degradation during the life cycle of bus stop pavements. The article presents the results of long-term rut depth measurements performed during 25 years on selected bus stops which were intended to determine correlation dependences of pavement rut depth on a number of design axles. The article also presents different methods for rut depth measurements including the straightedge test, Profilograph GE, TRIMBLE CX, and dynamic Road Scanner.

A Lattice Boltzmann method is used to analyse incompressible fluid flow in a two-dimensional cavity and flow in the channel past cylindrical obstacle. The method solves the Boltzmann’s transport equation using simple computational grid - lattice. With the proper choice of the collision operator, the Boltzmann’s equation can be converted into incompressible Navier-Stokes equation. Lid-driven cavity benchmark case for various Reynolds numbers and flow past cylinder is presented in the article. The method produces stable solutions with results comparable to those in literature and is very easy to implement.

Article presents the use of the meshless method for numerical simulation of incompressible fluid flow. The article presents the implementation of the meshless local Petrov-Galerkin method (MLPG), with Navier-Stokes equation formulated using the local weighted residual principle. The trial function construction process is the most important part of the meshless method implementation. In this article the radial basis functions (RBF) are used for the process of the trial functions construction.

The paper presents the use of the dual reciprocity multidomain singular boundary method (SBMDR) for the solution of the laminar viscous flow problem described by Navier-Stokes equations. A homogeneous part of the solution is solved using a singular boundary method with the 2D Stokes fundamental solution - Stokeslet. The dual reciprocity approach has been chosen because it is ideal for the treatment of the nonhomogeneous and nonlinear terms of Navier-Stokes equations. The presented SBMDR approach to the solution of the 2D flow problem is demonstrated on a standard benchmark problem - lid-driven cavity.

The paper presents the use of the multi-domain dual reciprocity method of fundamental solutions (MD-MFSDR) for the analysis of the laminar viscous flow problem described by Navier-Stokes equations. A homogeneous part of the solution is solved using the method of fundamental solutions with the 2D Stokes fundamental solution Stokeslet. The dual reciprocity approach has been chosen because it is ideal for the treatment of the non-homogeneous and nonlinear terms of Navier-Stokes equations. The presented DR-MFS approach to the solution of the 2D flow problem is demonstrated on a standard benchmark problem - lid-driven cavity.

The paper deals with use of the meshless method for incompressible fluid flow analysis. There are many formulations of the meshless methods. The article presents the Meshless Local Petrov-Galerkin method (MLPG) - local weak formulation of the Navier-Stokes equations. The shape function construction is the crucial part of the meshless numerical analysis in the construction of shape functions. The article presents the radial point interpolation method (RPIM) for the shape functions construction

The paper deals with use of the meshless method for soil bearing capacity analysis. There are many formulations of the meshless methods. The article presents the Meshless Local Petrov-Galerkin method (MLPG) - local weak formulation of the equilibrium equations. The main difference between meshless methods and the conventional finite element method (FEM) is that meshless shape functions are constructed using randomly scattered set of points without any relation between points. The Heaviside step function is test function used in the meshless implementation presented in the article. Heaviside test function makes weak formulation integral very simple, because only body integral in governing equation is due a body force.

In this paper, two meshless numerical algorithms are developed for the solution of two-dimensional steady-state diffusion equation that describes the stationary groundwater flow. The proposed numerical methods, which are truly meshless, quadrature-free and boundary only, are based on the method of fundamental solutions and singular boundary method respectively. The diffusion equation is transformed into a Poisson-type equation with a known fundamental solution. Numerical examples with moving boundary are presented and compared to the solutions obtained by the finite element method.

The boundary integral methods form one group of methods for solving differential equations. The boundary element method (BEM) is the basic method of this group. However, it requires the boundary mesh of elements and the evaluation of improper singular integrals, that arise due to fundamental solution singularity. Therefore, boundary meshless methods have recently have come into focus to remove these shortcomings. One of the most promising boundary collocation numerical schemes is the singular boundary method (SBM). To tackle the singularity of the fundamental solution, this method adopts the concept of original intensity factors (OIFs). The application of the proposed SBM scheme to groundwater flow in the cofferdam structure is presented and compared to the finite element method (FEM) solution.

This article focuses on the application of the meshless local Petrov-Galerkin (MLPG) method to solve the shallow water equations (SWE). This localized approach is based on the meshless weak formulation with the use of radial-basis functions (RBF) as the trial functions. Comparing with mesh-based methods, the present method is more efficient for large-scale problems with complex geometries. In this work, the numerical model is applied to simulate a dam-break problem as one of most descriptive benchmark problems for SWE. As a result, the adopted meshless method not only shows its algorithm applicability for class of problems described by SWE, but also brings more efficiency than several conventional mesh-based methods.

A meshless local method of approximated particular solutions (LMAPS) is used to analyze problem described by the convection-diffusion equation. The method solves the steady convection-diffusion equation with reaction term. The discretized system of equations is derived via interpolation procedure using integrated multiquadrics (MQ) radial basis functions (RBF). The solution of the equation is performed over simple geometry with non-uniform velocity field and results are presented in the article. The LMAPS method is capable to produce stable solutions with results comparable to the analytical solutions.