Load-Deformation Behavior of Shear Connectors in High Strength Concrete Subjected to Static and Fatigue Loading

Based on the low cyclic loading experiments on prestressed high strength concrete pipe piles, in which one of them was reinforced by steel fiber, another stirrup ratio, the other was not reinforced, the authors compare the results in terms of damage characteristic, hysteretic curve, bearing capacity, displacement and ductility. It is shown that the bearing capacity and ductility of prestressed high strength concrete pipe piles reinforced by steel fiber increases. With the increase of stirrup ratio, the hysteretic behavior and the deformation behavior of prestressed high strength concrete pipe piles improves.

Download Full-text

Mode II Behavior of High-Strength Concrete under Monotonic, Cyclic and Fatigue Loading

Materials ◽

10.3390/ma14247675 ◽

2021 ◽

Vol 14 (24) ◽

pp. 7675

Author(s):

Henrik Becks ◽

Martin Classen

Keyword(s):

Fatigue Life ◽

Compressive Stress ◽

Fatigue Damage ◽

High Strength Concrete ◽

High Strength ◽

Fatigue Loading ◽

Mode Ii ◽

Shear Tests ◽

Strength Concrete ◽

Mode Ii Loading

An economically efficient yet safe design of concrete structures under high-cycle fatigue loading is a rather complex task. One of the main reasons is the insufficient understanding of the fatigue damage phenomenology of concrete. A promising hypothesis states that the evolution of fatigue damage in concrete at subcritical load levels is governed by a cumulative measure of shear sliding. To evaluate this hypothesis, an experimental program was developed which systematically investigates the fatigue behavior of high-strength concrete under mode II loading using newly adapted punch through shear tests (PTST). This paper presents the results of monotonic, cyclic, and fatigue shear tests and discusses the effect of shear-compression-interaction and load level with regard to displacement and damage evolution, fracture behavior, and fatigue life. Both, monotonic shear strength and fatigue life under mode II loading strongly depend on the concurrent confinement (compressive) stress in the ligament. However, it appears that the fatigue life is more sensitive to a variation of shear stress range than to a variation of compressive stress in the ligament.

Download Full-text

Seismic performance of prefabricated high-strength concrete tube column–steel beam joints

Advances in Structural Engineering ◽

10.1177/1369433217726895 ◽

2017 ◽

Vol 21 (5) ◽

pp. 658-674 ◽

Cited By ~ 4

Author(s):

Xizhi Zhang ◽

Jiawei Zhang ◽

Xuejian Gong ◽

Shaohua Zhang

Keyword(s):

Seismic Performance ◽

High Strength Concrete ◽

Failure Modes ◽

High Strength ◽

Frame Structure ◽

Steel Beam ◽

Seismic Region ◽

Strength Concrete ◽

Shear Connectors ◽

Cracking Pattern

This study proposes a new type of fabricated hybrid frame structure, which is a prefabricated high-strength concrete tube column–steel beam joint hybrid frame structure. A series of six full-scale cruciform prefabricated high-strength concrete tube column–H-shaped beam joint specimens was tested under cyclic loading to investigate the seismic performance of the new fabricated hybrid frame structure. We designed the connection in the manner that the capacity of beam was higher than that of the column. The cracking pattern, failure modes, energy dissipation capacity, and strain profiles of the specimens were obtained and discussed. The test results showed that some specimens collapsed due to ring plate tearing failure and weld fracture, while other specimens collapsed due to column flexural failure. Shear connectors (i.e. shear studs and shear reinforcement) could ensure the reliable transmission of shear force, and the compound stirrups can effectively improve bearing capacity and joint ductility. The stiffness degradation of specimens was smooth with a linearly decreasing trend because of the prestressed reinforcement. The new joints could be applied in a seismic region.

Download Full-text