Identification of internal damages in reinforced concrete slabs using probability density field of acoustic emission events

To assess the structural capacity of reinforced concrete structures, identifying the internal cracks is important. Acoustic emission (AE) is promising to estimate the location of internal cracks. However, the localization is influenced by many factors like arrival time picking error, presence of crack, etc., resulting in localization error. The...

A rotating smeared crack approach in Sequentially Linear Analysis using the Elastic-brittle fraction model

Sequentially Linear Analysis (SLA), an event-by-event solution strategy in which a sequence of scaled linear analyses with decreasing secant stiffness is performed, representing local damage increments; is a robust alternative to nonlinear finite element analysis of quasi-brittle structures. Since it is based on a fixed smeared crack...

Probability density field of acoustic emission events: Damage identification in concrete structures

This paper proposes a new damage identification method, namely, the probability density field of acoustic emission (AE) events. This new method provides a different perspective to deal with the uncertainties in the source localization process. We treat the source location as a random variable, and estimate its probability density field based...

Material Characterization Approach for Modeling High-Strength Concrete after Cooling from Elevated Temperatures

Advanced numerical modeling of high-strength concrete (fc>60 MPa) structures designed to withstand severe thermal conditions requires detailed and reliable information on the mechanical properties of the material exposed to elevated temperatures. The only uniaxial compressive strength variation with temperature is not enough to satisfy the...

Experimental investigation of ASR-affected concrete – The influence of uniaxial loading on the evolution of mechanical properties, expansion and damage indices

The alkali silica reaction (ASR) in concrete causes internal localized swelling and micro cracking, which result in expansion and correlated deterioration of the concrete material. The stress state of the concrete is known to affect expansion due to ASR, with an anisotropic stress state giving rise to anisotropic expansion. Similarly, the...

Characterisation of Transverse Matrix Cracks in Composite Materials Using Fibre Bragg Grating Sensors

In this paper, we propose a novel approach to characterise barely visible transverse matrix cracks in composite structures using fibre Bragg grating (FBG) optical sensors. Matrix cracks are one of the most prevalent types of damage in composite structures, and detecting them in the internal layers of composites has remained a challenge. In...

A two-stage numerical analysis approach for the assessment of the settlement response of the pre-damaged historic Hoca Pasha Mosque

The current article presents a case study of the settlement response of the historic Hoca Pasha Mosque that involves uncertainties arising from the complex excavation activities, soil properties, building materials, and geometry and the presence of pre-existing cracks in the mosque’s walls. The objective is to demonstrate the added value of a...

Non-proportional loading for 3-D stress situations in Sequentially Linear Analysis

This article presents a new non-proportional loading strategy for Sequentially Linear Analysis (SLA), which is a robust secant stiffness based procedure for nonlinear finite element analysis of quasi-brittle materials, like concrete and masonry. The strategy is based on finding the principal planes for a total strain based fixed cracking model,...

Building response to tunnelling- and excavation-induced ground movements: using transfer functions to review the limiting tensile strain method

In this paper, limiting tensile strain method (LTSM) is reviewed, and advantages and disadvantages resulted from the simplicity of this method are examined in the light of the findings of the existing experimental and numerical studies. Using the viewpoint of the transfer functions for the LTSM, a more independent sight for the interpretation of...

Influence of the alkali-silica reaction on the mechanical degradation of concrete

The alkali-silica reaction (ASR) is an important problem that has yet to be completely understood. Owing to the complexity of this<br/>phenomenon, a number of studies have been conducted to characterize its kinetics, its impact on the material, and its structural consequences.<br/>This paper focuses on the deteriorating impact of ASR on concrete...

Ageing effects of alkali-silica reaction in concrete structures

The alkali-silica reaction (ASR) is a long-term deterioration process, which produces a hydrophilic and expansive gel causing damage. The ASR acts on concrete as an ageing phenomenon, modifying the material on the basis of its stress state. Focussing on the mechanical degradation of concrete, estimated trends for the mechanical properties in...

Damage functions for the vulnerability assessment of masonry buildings subjected to tunneling

This paper describes a new framework for the assessment of potential damage caused by tunneling-induced settlement to surface masonry buildings. Finite element models in two and three dimensions, validated through comparison with experimental results and field observations, are used to investigate the main factors governing the structural...

Multiscale material model for asr-affected concrete structures

One of the most harmful degradation process for concrete structures is the alkali-silica reaction. This process starts at aggregate level with a gel swelling and can produce damage up to macro level, by compromising the integrity and capacity of the structure. In order to better understand the complex nature of this phenomenon, a multiscale...

3D numerical analysis of tunnelling induced damage: The influence of the alignment of a masonry building with the tunnel axis

The development of infrastructure in major cities often involves tunnelling, which can cause damage to existing structures. Therefore, these projects require a careful prediction of the risk of settlement induced damage. The simplified approach of current methods cannot account for three-dimensional structural aspects of buildings, which can...

Coupled analysis of building damage due to tunneling

Excavation works in urban areas require a preliminary risk damage assessment. In historical cities, the prediction of building response to settlements is necessary to reduce the risk of damage of the architectural heritage. The current method used to predict the building damage due to ground deformations is the Limiting Tensile Strain Method ...

Modeling of long-term deformations and damage accumulation in masonry