scholarly journals Method of Designing a Friction-Based Wedge Anchorage System for High-Strength CFRP Plates

Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6443
Author(s):  
Wanxu Zhu ◽  
Wei Wei ◽  
Fengrong Liu ◽  
Rong Zeng

The cables of high-strength carbon fiber reinforced polymer (CFRP) plates are starting to be applied to large spatial structures. However, their main anchorage systems rely on the adhesive force, which entails risks to their integrity resulting from aging of the binding agent. In this study, a friction-based wedge anchorage system was designed for CFRP plates. The working mechanism of the proposed anchorage system was explored both theoretically and experimentally. The anti-slip mechanism and condition of CFRP plates were formulated so that the equivalent frictional angle of the contact surface between a CFRP plate and wedges must not be smaller than the sum of the dip angle of the wedge external conical surface and the frictional angle between the wedges and barrel. An analysis of the stress distribution in the anchorage zone of the CFRP plate was conducted using the Tsai-Wu failure criterion, which concluded that the compressive stresses should be reduced on the section closer to the load-bearing end of the anchorage system. Furthermore, the anchorage efficiency coefficient was proposed, which depends on stress concentration coefficients, plate thickness, length of anchorage zone, dip angle of wedge external conical surface, and its frictional angle. Then, it was determined that the minimum length of an anchorage zone for the CFRP plates with various specifications should be at least 49 times larger than the CFRP thickness. A finite element analysis and static tensile tests on six specimens were carried out. The experimental results revealed that the anchorage efficiency coefficient of the optimized anchor reached 97.9%.

2019 ◽  
Vol 795 ◽  
pp. 172-179
Author(s):  
Yan Qi Hu ◽  
Wieslaw K. Binienda

Braided composites have been widely used in aerospace and automotive structures due to their light weight and high strength. Unlike metal or laminated composite material, the complex braided structure brings a lot of challenges when conducting numerical simulation. In this paper, a finite element analysis based meso-mechanical modeling for the two dimensional triaxially braided composite was developed. This mesoscale modeling method is capable of considering the detailed braiding geometry and architecture as well as the mechanical behavior of fiber tows, matrix and the fiber tow interface. Furthermore, a multiscale model combined both macroscale and mesoscale approaches and it is realized within LS-DYNA environment through Interface_components and Interface_linking. This combined multiscale modeling approach enables the full advantage of both the macroscale and mesoscale approaches, which can describe the details of local deformation and the global overall response features of the entire structure with the minimum computational expense. The evaluation and verification of the mesoscale approach and combined multiscale modeling method is through a notched coupon tensile tests conducted by Kohlman in both axial and transverse direction. The multiscale modeling method captures the response feature accurately so it has the ability to analyze large scale structures.


2013 ◽  
Vol 671-674 ◽  
pp. 417-423
Author(s):  
Ji Xiong Liu ◽  
Shao Bin Dai ◽  
Yao Peng ◽  
Jun Huang

3 extended-end-plate joints of T-shaped concrete-filled rectangular composite tubular column with H-shaped beam were designed. The experimental research and ANSYS nonlinear finite element analysis on the earthquake resistance behaviors of the joints were conducted under low cyclic loading. The results indicate that the shapes of hysteresis curve of each specimen is full and presents spindle, all the specimens possess good energy dissipation capacity. The end-plate thickness and high-strength bolt diameter have a great influence on the bearing capacity of the joints. Increasing the thickness of end-plate and the diameter of high-strength bolt, the displacement ductility factors of the joints decrease slightly, but their ultimate bearing capacities obviously enhance. The stress distributions and the finite element failure characteristics of the joints are basically consistent with the test phenomena, yield bearing capacity and ultimate bearing capacity of the finite element calculations can agree well with the experimental results.


2020 ◽  
pp. 152808372097016
Author(s):  
Mithilesh Kumar Dewangan ◽  
SK Panigrahi

The present research deals with the finite element analysis (FEA) considering high strength Kevlar/epoxy composites as a target plate subjected to ballistic impact by varying nose-shaped projectiles. A multi-scale modelling technique has been implemented with FEA to design the intricate weave architecture. The damage properties are adopted using a user-defined function in the explicit analysis. The proposed methodology is validated by the available literature. The conical-shaped projectiles will have more damage and penetration as compared to the flat projectiles, which are studied for two plate thickness. The conical 60° and conical 90° projectiles will have better penetration to the target plate even for the increased thickness, whereas the Conical 120° and Flat projectiles will have a significant reduction in residual velocities. Also, with the increment in thickness, the energy absorption will significantly increase for Flat projectiles as compared to the conical projectiles. For lower velocities, the yarn slippage and puncturing are the major factors of failure along with fiber breakage and matrix cracking. As the velocities increased, the dominant phenomena of failure will be the linear momentum transfer.


2021 ◽  
Author(s):  
Masaki Fujiwara ◽  
Takashi Yamaguchi ◽  
Senju Kozai

<p>According to the new Japanese Specifications for Highway Bridges, after-slip behavior should be verified in high-strength bolted frictional joints. Previous studies have investigated slip behavior with a filler plate. They have proposed the reduction factor of slip resistance. On the other hand, the ultimate strength of such a joint with a filler plate is not clear, and its design strength considering after-slip behavior is not also specified. In this study, for high-strength bolted frictional joints with various filler plate thicknesses, tensile tests and FEA were carried out. From obtained results, it was revealed that a filler plate did not resist load in bearing, and the number of bolt shear failure surfaces was decreased to one from two by a filler plate. It is also found that bolt shear strength decreased below the designed value as filler plate thickness is increased. The authors also proposed the simple design model for bolt shear strength in the frictional joints with a filler plate.</p>


2019 ◽  
Vol 9 (23) ◽  
pp. 5258
Author(s):  
Fang Wang ◽  
Mian Wu ◽  
Genqi Tian ◽  
Zhe Jiang ◽  
Shun Zhang ◽  
...  

A flat cover of an adjustable ballast tank made of high-strength maraging steel used in deep-sea submersibles collapsed during the loading process of external pressure in the high-pressure chamber. The pressure was high, which was the trigger of the collapse, but still considerably below the design limit of the adjustable ballast tank. The failure may have been caused by material properties that may be defective, the possible stress concentration resulting from design/processing, or inappropriate installation method. The present paper focuses on the visual inspections of the material inhomogeneity, ultimate cause of the collapse of the flat cover in pressure testing, and finite element analysis. Special attention is paid to the toughness characteristics of the material. The present study demonstrates the importance of material selection for engineering components based on the comprehensive properties of the materials.


2021 ◽  
Vol 16 (2-3) ◽  
pp. 61-74
Author(s):  
Sahar Ghasemi ◽  
Amir Mirmiran ◽  
Yulin Xiao ◽  
Kevin Mackie

A super lightweight deck can enhance load rating and functionality of a bridge, especially those identified as structurally deficient. This study was aimed to develop and experimentally validate a novel bridge deck as an ultra-lightweight low-profile waffle slab of ultra-high-performance concrete (UHPC) with either carbon fiber reinforced polymer (CFRP) or high strength steel (HSS) reinforcement. The proposed system lends itself to accelerated bridge construction, rapid deck replacement in bridges with load restrictions, and bridge widening applications without the need to replace girders. Performance and failure modes of the proposed deck were initially assessed through extensive lab experiments and finite element analysis, which together confirmed that the proposed deck panel meets the AASHTO LRFD requirements. The proposed deck system is not susceptible to punching shear of its thin slab and fails in a rather ductile manner. To evaluate its long-term performance, the system was further tested under the dynamic impact of wheel load at the Accelerated Pavement Testing (APT) facility of the Florida Department of Transportation using a Heavy Vehicle Simulator (HVS).


Metals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1136
Author(s):  
Marcel Carpio ◽  
Jessica Calvo ◽  
Omar García ◽  
Juan Pablo Pedraza ◽  
José María Cabrera

Designing a new family of advanced high-strength steels (AHSSs) to develop automotive parts that cover early industry needs is the aim of many investigations. One of the candidates in the 3rd family of AHSS are the quenching and partitioning (QP) steels. These steels display an excellent relationship between strength and formability, making them able to fulfill the requirements of safety, while reducing automobile weight to enhance the performance during service. The main attribute of QP steels is the TRIP effect that retained austenite possesses, which allows a significant energy absorption during deformation. The present study is focused on evaluating some process parameters, especially the partitioning temperature, in the microstructures and mechanical properties attained during a QP process. An experimental steel (0.2C-3.5Mn-1.5Si (wt%)) was selected and heated according to the theoretical optimum quenching temperature. For this purpose, heat treatments in a quenching dilatometry and further microstructural and mechanical characterization were carried out by SEM, XRD, EBSD, and hardness and tensile tests, respectively. The samples showed a significant increment in the retained austenite at an increasing partitioning temperature, but with strong penalization on the final ductility due to the large amount of fresh martensite obtained as well.


Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 532
Author(s):  
A Jo ◽  
Myeong Jeong ◽  
Sang Lee ◽  
Young Moon ◽  
Sun Hwang

A multi-stage cold forging process was developed and complemented with finite element analysis (FEA) to manufacture a high-strength one-body input shaft with a long length body and no separate parts. FEA showed that the one-body input shaft was manufactured without any defects or fractures. Experiments, such as tensile, hardness, torsion, and fatigue tests, and microstructural characterization, were performed to compare the properties of the input shaft produced by the proposed method with those produced using the machining process. The ultimate tensile strength showed a 50% increase and the torque showed a 100 Nm increase, confirming that the input shaft manufactured using the proposed process is superior to that processed using the machining process. Thus, this study provides a proof-of-concept for the design and development of a multi-stage cold forging process to manufacture a one-body input shaft with improved mechanical properties and material recovery rate.


2011 ◽  
Vol 346 ◽  
pp. 379-384
Author(s):  
Shu Bo Xu ◽  
Yang Xi ◽  
Cai Nian Jing ◽  
Ke Ke Sun

The use of finite element theory and modal analysis theory, the structure of the machine static and dynamic performance analysis and prediction using optimal design method for optimization, the new machine to improve job performance, improve processing accuracy, shorten the development cycle and enhance the competitiveness of products is very important. Selected for three-dimensional CAD modeling software-UG NX4.0 and finite element analysis software-ANSYS to set up the structure of the beam finite element model, and then post on the overall structure of the static and dynamic characteristic analysis, on the basis of optimized static and dynamic performance is more superior double wall structure of the beam. And by changing the wall thickness and the thickness of the inner wall, as well as the reinforcement plate thickness overall sensitivity analysis shows that changes in these three parameters on the dynamic characteristics of post impact. Application of topology optimization methods, determine the optimal structure of the beam ultimately.


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