Evaluation and Observation of Autogenous Healing Ability of Bond Cracks along Rebar
نویسندگان
چکیده
Micro cracks occurring in concrete around tensile rebar is well known latent damage phenomenon. These micro cracks develop, and can be detected after reaching the surface of the concrete. Detection of these cracks before they are fully formed is preferable, but observing the whole crack structure is difficult. Another problem is repairing micro cracks under the concrete surface. The autogenous ability of bond cracks along rebar was evaluated using the air permeability test. Air permeability coefficients were measured before and after tensile loading, and experimental air permeability coefficients became larger near cracks along rebar as a result of tensile loading. Recuring for 28 days after tensile loading made the air permeability coefficients smaller, but this restriction only occurred during water recuring. Observation of crack patterns helped the understanding of change in the air permeability coefficients. Several small cracks along rebar were observed after tensile loading, and most cracks along rebar were not found after water recuring. On the other hand, the crack pattern did not change after air recuring. These results indicate that bond cracks along rebar can be closed by autogenous healing, and cause the air permeability coefficients.
منابع مشابه
Effect of Impressed Current on Bond Strength Between Steel Rebar and Concrete
The deterioration of bond strength between reinforcing steel and concrete as a result of impressed cathodic current with respect to the exposure time was investigated. A current in the magnitude of 3ma/ft2 (based on reinforcing rebar area) was used for a period of five years. Chemical analyses for sodium (Na+), potassium (K+) and chloride (Cl-) ions in concrete cylinders were performed as a fun...
متن کاملModeling of Self-Healing Concrete: A Review
Self-healing concrete (SHC) has received a tremendous attention due to its advanced ability of automatic crack detection and crack repairing compared to the standard concrete. Two main approaches which considered as to-date self-healing mechanisms are autogenous and autonomous healing. In the past several years, the effort of the research has been focused on experimental works instead of numeri...
متن کاملThe Effect of Autogenous Peritoneal Graft Augmented with Platelets- Plasma Rich Protein on the Healing of Induced Achilles Tendon Rupture, in Dogs
BACKGROUND: <span style="color: #221e1f; font-family: Times New Roman,...
متن کاملEffect of Autogenous Omental Free Graft on the Biomechanical Properties of Fracture Healing in Dog
Objective- To evaluate greater omentum as an autogenous free graft in enhancing bone healing.Design- Prospective descriptive trial.Animals- Ten mongrel adult dogs, 3 to 4 years old and weighing 25.2 to 31 kg, assigned into two equal experimental and control groups (5dogs/group), were used.Procedures- Mid-shaft osteotomy on right radius was followed by a partial omentectomy in all dogs. A 30x30 ...
متن کاملThe effect of butyric acid with autogenous omental graft on healing of experimental Achilles tendon injury in rabbits
In this study, the role of local injection of butyric acid (BA) with autogenous omental graft was evaluated in healing of experimental Achilles tendon injury in rabbits. Nine adult male New Zealand rabbits were anesthetized and a partial thickness tenotomy was created on both hindlimbs. In treated group, omental graft was secured in place using BA soaked polygalactin 910 suture. In control grou...
متن کامل