基于分段步进式弹塑性格构模型的混凝土破坏过程细观模拟

The classically lattice model assumes the local elements behave elastic brittle, neglecting the ductility of the mortar matrix. This leads to the simulated load⁃displacement response more brittle than the realistic. To solve the aforementioned issue, a piece⁃wise approach was introduced to describe the elastic⁃plastic constitutive relation of...

Experimentally validated meso-scale fracture modelling of mortar using output from micromechanical models

This paper presents a validation process of the developed multi-scale modelling scheme on mortar composites. Special attention was paid to make the material structure of real and virtual mortar specimens comparable at the meso-scale. The input mechanical parameters of cement paste (both bulk cement paste and interfacial transition zone) at the...

Discrete lattice fracture modelling of hydrated cement paste under uniaxial compression at micro-scale

A combination of laboratory experiments and numerical simulations at multiple length scales can provide in-depth understanding of fracture behaviour of hydrated cement paste (HCP). To that end, the current work presents a numerical study on compressive failure of hydrated cement paste (HCP) at the micro-scale. Virtual specimens consisting of...

Frost Damage Progression Studied Through X-Ray tomography In Mortar With Phase Change Materials

The potential of using phase change materials (PCM) in cementitious materials to mitigate damage due to thermal loadings has been recently focus of intensive research. In the case of PCM with transition temperatures near to the freezing point of water, their potential to delay frost in a cementitious matrix has been largely investigated through...

Micro-Cantilever Testing Of Cementitious Materials Under Various Loading Conditions

Nanoindentation is usually used to investigate local elastic properties and hardness of materials. In this paper, the nanoindenter served as a loading tool to perform micro scale bending tests and measure the global response of micro-scale specimens. For testing, cement paste cantilever beams with a square cross-section of 300 μm × 300 μm were...

Size effect on splitting strength of hardened cement paste: Experimental and numerical study

Cement paste possesses complex microstructural features including defects/pores over a range of length-scales, from nanometres to millimetres in size. As a consequence, it exhibits different behaviour under loading depending on the size. In this work, cubic specimens in a size range of 1: 400 were produced and tested by a one-sided splitting...

Using nano-indentation and microscopy to obtain mechanical properties

Simulation of mechanical behaviour of heterogeneous materials is only possible if the local properties of the components are known. In recent years nano-indentation is being applied on different levels to obtain local mechanical properties. The aim of this paper is to explore various ways to obtain these properties by combining nano-indentation...

A tool for concrete performance assessment for ASR affected structures: An outlook

This paper outlines a project (namely PAT-ASR) which entails the development of a multi scale material performance assessment model on simulation of alkali silica reaction deployment and its effects on concrete durability. Performance models require a multi scale approach from micro (namely reaction chemistry) to macro level studies (namely...