Laboratory-numerical evaluation of the tensile strength of fibers in self-compacting concrete

نوع: Type: thesis

مقطع: Segment: masters

عنوان: Title: Laboratory-numerical evaluation of the tensile strength of fibers in self-compacting concrete

ارائه دهنده: Provider: Mehran Soleimani

اساتید راهنما: Supervisors: Mahmuod Nili (Ph.D)

اساتید مشاور: Advisory Professors:

اساتید ممتحن یا داور: Examining professors or referees: Mostafa Moghadasi(Ph.D) & Mehdi Hoseinian (Ph.D)

زمان و تاریخ ارائه: Time and date of presentation: 2024/01/31

مکان ارائه: Place of presentation: Seminar2

چکیده: Abstract: Nowadays, the application and use of self-compacting concrete is increasing due to the complexity of structures. Self-compacting concrete is a new type of concrete that is widely used in conditions of rebar crowding, and the ability to pass, homogeneity, and non-separation are among the advantages of this type of concrete. Weakness of reinforced concrete parts in tensile and shear strength is one of the important problems in concrete structures. To improve the conditions and prevent the creation and expansion of cracks in concrete structures, most researchers have recommended the use of different fibers, including steel fibers and polypropylene fibers. It should be noted that the use of steel fibers is used in priority to control cracks and increase load capacity. In this regard, the geometrical characteristics of the end hooks of steel fibers are effective parameters that have a significant effect on the continuity and resistance to external elongation, which can behave properly in structures under the effect of dynamic loads. In the first part of this thesis, the effect of steel fibers without end hooks and also with 5D hooks on the tensile strength of normal and self-compacting concretes has been evaluated in the laboratory. In the second part of the research, with the help of the information from the first part, the tensile strength of 4D and 3D fibers has been calculated numerically. The obtained results have shown that the strength of fiber cohesion in normal and self-compacting concrete was highly dependent on the number of end hooks. On the other hand, compressive and pullout resistance in self-compacting concrete has increased compared to normal concrete in all designs. The results of the present research indicate that within the range of the obtained results, the current calculation method in estimating the tensile strength of 3D, 4D and 5D fibers in normal and self-compacting concretes has been of good accuracy