The unexpected softening of the undrained shear strength of organic and silty clays in Rhine delta: a conceptual study: Determining the Undrained Shear Strength of soft Dutch soils using conventional laboratory equipment

The current Dutch norms for the macro-stability of ood protection embankments and more specifically the determination of SHANSEP parameters has been subject of debate since its implementation in 2017. The main concerns arise from the apparent over-conservative nature of the guidelines and the apparent underestimation of shear strength of organic...

Quality assessment and quality control system for armourstones; by the use of simple testing tools

Several waterway protection structures in the Netherlands dealt with rapid degrading armourstone after construction. This suggests that the current selection procedure of armourstones is not flawless to all degradation mechanisms, especially in dynamic environments. In this work armourstone is meant to include all rock that is used in river,...

A parametric study on the bounding surface SANICALY model for cyclic behaviour of Kaolin clay

Cyclic loading tends to affect the strength and stiffness parameters of soils, degrade its structure and results in accumulation of the excess pore water pressure. Such behaviour often leads to premature failure of the soils. Over the past few decades, geotechnical research community has developed numerous constitutive models to predict the...

Preloading of a lumpy clay fill: A study into the closure of the interlump voids of a mechanically dredged stiff clay fill

Mechanical dredging of a stiff clay results in clay lumps. Those clay lumps can be reused for the construction of land reclamation projects, and hereby economic and environmental value is generated. Placement of the clay lumps<br/>in water result in a matrix of clay lumps and an interlump void space. The collapse of the interlump void space will...

Experimental analysis of passive acoustic emission, in particular the Kaiser Effect, under dynamic stress conditions: Exploring the implications for in-situ failure monitoring in underground mines

Irreversible damage induced by stress in brittle rock is accompanied by the formation of micro-cracks. The strain energy released during the fracturing process is released in the form of acoustic emission. This thesis applied the non-intrusive method of acoustic emission monitoring to assess the deformation process of brittle rock during...

The influence of mechanical contrast on industrial and natural hydraulic fracturing

The heterogeneity of layered systems leads to variation in rock or soil mechanical properties, influencing the resistance to failure. A formation breaks by fracture propagation when the effective stress surpasses the formation strength. The propagation of a fracture through a mechanical interface depends on whether the formation strength of the...

A Local Time-Stepping Method for Multiphase Flow in Porous Media

Simulation of multiphase flow in natural subsurface formations include selection of time-step size, i.e., the discrete snapshots (steps) over which the time-dependent nonlinear process is investigated. The simulation results would naturally depend on the size of the discrete time step, according to the order of accuracy of the implemented...

Evaluation of transport properties of radionuclides in clay materials

Feasibility study of Dutch concept of deep geological repository for radioactive waste is at present widely conducted in the Netherlands. In this project, transport properties of selenate ion in clay materials were investigated. Apparent diffusion coefficients of selenate ion were obtained as results. To study possible alternations of Boom Clay...