Physical and mechanical behaviors of thermally modified rubberwood glulam beam under sustained cyclic loading

2020 ◽  
Vol 52 (3) ◽  
pp. 298-312
Author(s):  
T. Pulngern ◽  
T. Udtaranakron ◽  
K. Chanto
Keyword(s):  
Cyclic Loading ◽  
Mechanical Behaviors ◽  
Glulam Beam

Disc Mechanics With Trans-Endplate Partial Nucleotomy are not Fully Restored Following Cyclic Compressive Loading and Unloaded Recovery

2006 ◽  
Vol 128 (6) ◽  
pp. 823-829 ◽  
Author(s):  
Edward J. Vresilovic ◽  
Wade Johannessen ◽  
Dawn M. Elliott
Keyword(s):  
Cyclic Loading ◽  
Stress Relaxation ◽  
Nucleus Pulposus ◽  
Time Constant ◽  
Annulus Fibrosus ◽  
Compressive Loading ◽  
Magnetic Resonance Images ◽  
Mechanical Behaviors ◽  
Short Time

Mechanical function of the intervertebral disc is maintained through the interaction between the hydrated nucleus pulposus, the surrounding annulus fibrosus, and the superior and inferior endplates. In disc degeneration the normal transfer of load between disc substructures is compromised. The objective of this study was to explore the mechanical role of the nucleus pulposus in support of axial compressive loads over time. This was achieved by measuring the elastic slow ramp and viscoelastic stress-relaxation mechanical behaviors of cadaveric sheep motion segments before and after partial nucleotomy through the endplate (keeping the annulus fibrosus intact). Mechanics were evaluated at five conditions: Intact, intact after 10,000cycles of compression, acutely after nucleotomy, following nucleotomy and 10,000cycles of compression, and following unloaded recovery. Radiographs and magnetic resonance images were obtained to examine structure. Only the short time constant of the stress relaxation was altered due to nucleotomy. In contrast, cyclic loading resulted in significant and large changes to both the stiffness and stress relaxation behaviors. Moreover, the nucleotomy had little to no effect on the disc mechanics after cyclic loading, as there were no significant differences comparing mechanics after cyclic loading with or without the nucleotomy. Following unloaded recovery the mechanical changes that had occurred as a consequence of cyclic loading were restored, leaving only a sustained change in the short time constant due to the trans-endplate nucleotomy. Thus the swelling and redistribution of the remaining nucleus pulposus was not able to fully restore mechanical behaviors. This study reveals insights into the role of the nucleus pulposus in disc function, and provides new information toward the potential role of altered nucleus pulpous function in the degenerative cascade.

Effect of Partition on the Mechanical Behaviors of Soft Adhesive Layers

2019 ◽  
Vol 86 (6) ◽  
Author(s):  
Danming Zhong ◽  
Junjie Liu ◽  
Yuhai Xiang ◽  
Tenghao Yin ◽  
Wei Hong ◽  
...  
Keyword(s):  
Cyclic Loading ◽  
Structural Design ◽  
Adhesive Layer ◽  
Mechanical Behaviors ◽  
Adhesive Layers ◽  
Mechanical Responses ◽  
Aspect Ratios ◽  
Instability Modes ◽  
Tensile Curve ◽  
Partition Process

A soft adhesive layer bonded between two rigid substrates, which are being pulled apart, may exhibit diverse instability phenomena before failure, such as cavitation, fingering, and fringe instability. In this study, by subdividing the soft layers into different numbers of disconnected smaller parts, we achieve desired instability modes and mechanical responses of the layer. The partition process not only retains the monotonicity on the tensile curve but also tunes the modulus and stretchability of the adhesive layer. Meanwhile, cavitation in layers of large aspect ratios is suppressed, and the hysteresis during cyclic loading is reduced. This study provides a guideline for the structural design of soft joints and adhesive layers.

scholarly journals Experimental Study on Precast Concrete Shear Walls with Different Hollow Slabs

2014 ◽  
Vol 8 (1) ◽  
pp. 166-171 ◽  
Author(s):  
Qinyan Zhao ◽  
Zhongyong Zhang ◽  
Jiliang Liu ◽  
Mingjin Chu
Keyword(s):  
Experimental Study ◽  
Cyclic Loading ◽  
Failure Mode ◽  
Shear Failure ◽  
Precast Concrete ◽  
Shear Walls ◽  
Test Results ◽  
Mechanical Behaviors ◽  
Low Cyclic Loading

To study mechanical behaviors of shear walls built with precast two-way hollow slabs, two shear walls with different details of hollow slabs were quasi-statically tested under low cyclic loading. The failure mode was analyzed, which vertical macro-cracks appeared on walls due to the details of hollow slabs. Brittle shear failure can be avoided in terms of the failure behaviors evolved from integral wall to the combination of wall and columns. Test results also show that that dimension of transverse holes can affect compressive capacity of the walls when it is larger than that of longitudinal holes in the hollow slab.

Mechanical behaviors of multi-filament twist superconducting strand under tensile and cyclic loading

Cryogenics ◽  
2016 ◽  
Vol 73 ◽  
pp. 14-24 ◽  
Author(s):  
Xu Wang ◽  
Yingxu Li ◽  
Yuanwen Gao
Keyword(s):  
Cyclic Loading ◽  
Mechanical Behaviors

Mechanical behaviors of class II composite restorations under cyclic loading

2014 ◽  
Vol 30 ◽  
pp. e88-e89
Author(s):  
S.F. Chuang ◽  
X.F. Hong ◽  
T.Y.F. Chen
Keyword(s):  
Cyclic Loading ◽  
Class Ii ◽  
Mechanical Behaviors ◽  
Composite Restorations

scholarly journals Mechanical Behavior, Energy Release, and Crack Distribution Characteristics of Water-Saturated Phyllite under Triaxial Cyclic Loading

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Yang Zhou ◽  
Shengrui Su ◽  
Peng Li
Keyword(s):  
Cyclic Loading ◽  
Mechanical Behavior ◽  
Energy Release ◽  
Damage Variable ◽  
Dissipated Energy ◽  
Distribution Characteristics ◽  
Mechanical Behaviors ◽  
Dynamic Mechanical ◽  
Crack Distribution ◽  
Water Saturated

Many geological engineering hazards are closely related to the dynamic mechanical behaviors of rock materials. However, the dynamic mechanical behaviors of phyllite are less studied. In this study, we have carried out a series of triaxial cyclic tests on dry and water-saturated phyllite by employing the MTS 815 servohydraulic testing system and AE testing equipment to reveal the mechanical behavior, energy release, and crack distribution characteristics of phyllite. Results show that phyllite is a water-sensitive rock. Water and cyclic loading substantially affect the compressive strength, crack damage stress, deformation parameters, dilatancy, energy release, and crack distribution characteristics of phyllite. Furthermore, based on the dissipated energy, a new damage variable for phyllite is established. The critical damage variable for phyllite is approximately 0.80; this variable can be used as an index to predict the failure of phyllite. The water saturation effect of phyllite is very obvious; that is, it results in the weakness of mechanical properties of phyllite and changes the AE energy release and crack distribution characteristics of phyllite. This research can provide guidance for engineering construction and disaster prevention and control.

Experimental analysis of off-axis mechanical behaviors of PVC coated fabrics subjected to cyclic loading

2019 ◽  
Vol 80 ◽  
pp. 106090 ◽  
Author(s):  
Junhao Xu ◽  
Yingying Zhang ◽  
Meng Wu ◽  
Yushuai Zhao
Keyword(s):  
Cyclic Loading ◽  
Experimental Analysis ◽  
Mechanical Behaviors ◽  
Coated Fabrics

Impacts of Initial Deviator Stress and Cyclic Confining Pressure on Mechanical Behaviors of Ningbo Clay under Cyclic Loading

2021 ◽  
Vol 21 (4) ◽  
pp. 06021004
Author(s):  
Juehao Huang ◽  
Jian Chen ◽  
Wenhui Ke ◽  
Fusheng Liu ◽  
Youyan Bian
Keyword(s):  
Cyclic Loading ◽  
Confining Pressure ◽  
Mechanical Behaviors ◽  
Deviator Stress
Sign in / Sign up

Export Citation Format

Share Document