Evaluation of acoustic emission source localization accuracy in concrete structures

Acoustic emission source localization is a promising monitoring technique for concrete structures. However, the accuracy of acoustic emission source localization is influenced by many factors, such as the presence of cracks, which are commonly observed in existing reinforced concrete structures. In this article, the acoustic emission source...

Reduction of water permeation through cracks in mortar by addition of bacteria based healing agent

Field performance of bacteria-based repair system: Pilot study in a parking garage

This paper presents the field performance in a parking garage of the recently developed bacteria-based repair system for concrete. This liquid-based repair system aims at the sealing of cracks and decrease of the porosity due to the production of a calcium-based biomineral. The system combines advantages of both a traditional repair system for...

Shear Resistance of Reinforced Concrete Beams without Shear Reinforcement under Sustained Loading

Development of self-healing granules having semi-capsulation effect by using cement compound, chemical/mineral admixtures & its watertight performance through crack

Granulation technique, introducing the self-healing ability to concrete, was developed by Koide, 2010 [1] based on the capsulation technology in the food/medicine industry. In this research, self-healing granules, containing cement compounds, chemical and mineral admixtures, were fabricated by a proposed granulation process and the capability of...

Interaction between microcapsules and cementitious matrix after cracking in a self-healing system

A new type of self-healing cementitious composites by using organic microcapsules is designed in Guangdong Key Laboratory of Durability for Coastal Civil Engineering, Shenzhen University. For the organic microcapsules, the shell material is urea formoldehyde (UF), and the core healing agent is Epoxy. The effect of organic microcapsules on...

Resistance of cracked concrete healed by means of polyurethane against chloride penetration

A lot of damage is reported for constructions in marine environments. Marine environments are very aggressive, because of the high chloride concentration in sea water. Chlorides affect durability by initiating corrosion of the reinforcement steel. When cracks appear in the concrete structures, chlorides will penetrate faster and will initiate...

Time-dependent behavior of cracked concrete beams under sustained loading

Under sustained loading, the propagation of cracks in concrete is assumed to be related to the elastic deformation, material parameters and time. Based on the fictitious crack model (FCM), a finite element method is proposed to explain the behavior of cracks in time using current constitutive relations to approximate the time-dependent crack...

Crack width in reinforced steel fibre concrete

Nowadays durability plays a bigger and bigger role in structures. The so-called crack width is a very important issue in the durability. The addition of steel fibres to the concrete matrix is not unheard of and tests concluded that the crack width can be reduced. Currently steel fibres are added to the concrete matrix in different projects,...