Monotonic and Cyclic Performance of Sand from Natural Alluvial Deposits

Author: Julijana Bojadjieva

Book Series : Springer Series in Geomechanics and Geoengineering

Part of: Springer Professional "Wirtschaft+Technik" , Springer Professional "Technik" , Springer Professional "Wirtschaft"

Table of Contents

About this book

This book presents a comprehensive experimental investigation, consisting of element scale—triaxial and simple shear tests and model scale—shaking table tests, to examine the monotonic and cyclic behavior of Skopje sand. Skopje sand is silica sand from natural alluvial river deposits collected from the river terraces of Vardar river in the city of Skopje, Macedonia. Numerical simulation of the element monotonic and cyclic tests is also presented using the hypoplastic material model. Particular focus is given on the liquefaction potential of the tested material.

While there were no well-documented cases of liquefaction during the 1963 Skopje earthquake with a magnitude of 6.1, significant structural damage was attributed to pronounced site amplification effects of sand materials in the Vardar valley. Given the absence of seismic geotechnical codes in the region at that time, the lack of a seismic monitoring network, and limited knowledge about the city's geotechnical properties, there is the assumption that liquefaction might have occurred but went undocumented and unassessed due to the overwhelming structural damage and other post-earthquake disaster management activities.

The generated experimental data of Skopje sand serve as a foundational dataset for students and researchers into continuous more advanced experimental research in the field, validating numerical modeling focusing on liquefaction phenomena, soil dynamics, induced settlement of buildings, and evaluating effective mitigation strategies. The conducted investigations provide a strong basis for sustainable research on element and model scale in the Laboratory for Soil Dynamics and Geotechnical Engineering at the Department of Geotechnics and Special Structures, Institute of Earthquake Engineering and Engineering Seismology-IZIIS, Skopje, Macedonia.

Frontmatter

Chapter 1. Introduction

Abstract

Earthquakes represent a major natural hazard that regularly exert impacts upon the built environment in seismic prone areas worldwide and cause social and economic losses. Recent earthquakes, for example, the 2023 earthquake in Turkey, showed that many of the damages and economic losses were related to geotechnical problems and liquefaction.

Julijana Bojadjieva

Chapter 2. Skopje Sand-Natural Alluvial Sand

Abstract

The city of Skopje has suffered an earthquake in 1963 with a magnitude 6.3. Based on the damages to the building environment, the earthquake intensity was classified as zone IX, due to the catastrophic failure observed in the building stock. Yet, almost not a single damage associated to the geotechnical conditions of the ground has been reported due to the lack of previous data on the cyclic behavior of the soil.

Julijana Bojadjieva

Chapter 3. Monotonic and Cyclic Performance of Skopje Sand Based on Element Tests

Abstract

Extensive monotonic and cyclic tests were accomplished on the triaxial and simple shear apparatus in the Laboratory for Soil Dynamics and Foundation Engineering at IZIIS.

Julijana Bojadjieva

Chapter 4. Model Tests on Shaking Table

Abstract

The ideal container is the one that gives a seismic response of the soil model identical to that obtained in the case of the prototype, i.e., the semi-infinite soil layer 1D response under vertically propagating shear waves. The boundary conditions created by the model container walls have to be considered carefully, otherwise the field conditions cannot be simulated properly. The presence of rigid and smooth end walls in the ground model introduce three serious boundary effects compared with a semi-infinite soil layer in a prototype: deformation incompatibility, stress dissimilarity and input excitation pattern dissimilarity (Carvalho et al., 2010). Bhattacharya et al. (2012) provides a review and discussion about all six different types of model container designs:

Julijana Bojadjieva

Chapter 5. Numerical Simulation of Experimental Tests

Abstract

Since, in this book, a comprehensive experimental investigation was performed on a new type of sand—the Skopje sand, the necessity for numerical analysis of the experiments arose due to the following purposes.

Julijana Bojadjieva

Chapter 6. Conclusions

Abstract

A thorough experimental program at the element scale has been devised to acquire essential data regarding the dynamic properties and liquefaction susceptibility of sand sourced from the Vardar River terraces, known as Skopje sand. Despite the absence of documented historic liquefaction events, the high susceptibility of these sands and the significant earthquake damage witnessed during the 1963 Skopje earthquake underscore the imperative for assessment and enhanced comprehension of soil behavior under cyclic loading within the scientific and engineering communities.

Julijana Bojadjieva

Backmatter

Title: Monotonic and Cyclic Performance of Sand from Natural Alluvial Deposits
Author: Julijana Bojadjieva
Publisher: Springer Nature Switzerland
Electronic ISBN: 978-3-031-76200-0
Print ISBN: 978-3-031-76199-7
DOI: https://doi.org/10.1007/978-3-031-76200-0