RELATIONSHIP BETWEEN SHEAR FORCE AND SLIP OF REINFORCING BAR IN A JOINT INTERFACE OF HALF PRECAST RC STRUCTURE

2021 ◽  
Vol 77 (1) ◽  
pp. 1-14
Author(s):  
Ryosuke TAKAHASHI ◽  
Hiroshi SHIMA ◽  
Satoshi MATSUOKA ◽  
Satoshi TSUCHIYA
Keyword(s):  
Shear Force ◽  
Joint Interface ◽  
Reinforcing Bar ◽  
Rc Structure

Effect of Thickness of Pd Plating Layer on Shear Strength of Lead-Free Solder Ball Joint With Electroless Ni/Pd/Au Plated Electrode

2011 ◽  
Author(s):  
Takahiro Kano ◽  
Ikuo Shohji ◽  
Tetsuyuki Tsuchida ◽  
Toshikazu Ookubo
Keyword(s):  
Reaction Layer ◽  
Shear Force ◽  
Solder Ball ◽  
Lead Free ◽  
Joint Interface ◽  
Lead Free Solder ◽  
Solder Balls ◽  
Free Solder ◽  
Ball Joints ◽  
Electroless Ni

An electroless Ni/Pd/Au plated electrode is expected to be used as an electrode material for lead-free solder to improve joint reliability. The aim of this study is to investigate the effect of the thickness of the Pd layer on joint properties of the lead-free solder joint with the electroless Ni/Pd/Au plated electrode. Solder ball joints were fabricated with Sn-3Ag-0.5Cu (mass%) lead-free solder balls and electroless Ni/Pd/Au and Ni/Au plated electrodes. Ball shear force and microstructure of the joint were investigated. The (Cu,Ni)6Sn5 reaction layer formed in the joint interface in all specimens. The thickness of the reaction layer decreased with increasing the thickness of the Pd layer. In the joint with a Pd layer 0.36 μm thick, the remained Pd layer was observed in the joint interface. In the joint, impact shear force decreased compared with that of the joint without the remained Pd layer. On the contrary, when the thickness of the Pd layer was less than 0.36 μm, the Pd layer was not remained in the joint interface and impact shear force improved. Impact shear force of the joint with the electroless Ni/Pd/Au plated electrode was higher than that with the electroless Ni/Au one.

Effect of Cooling Rate on Intermetallic Compounds Formation in Sn-Ag-Cu-In Solder

2018 ◽  
Vol 941 ◽  
pp. 2075-2080
Author(s):  
Kenji Miki ◽  
Tatsuya Kobayashi ◽  
Ikuo Shohji ◽  
Yusuke Nakata
Keyword(s):  
Solder Joint ◽  
Cooling Rate ◽  
Shear Force ◽  
Bonding Temperature ◽  
Lead Free ◽  
Joint Interface ◽  
Lead Free Solder ◽  
Vacuum Atmosphere ◽  
Free Solder ◽  
Large Formation

The effect of the cooling rate in bonding on IMCs formation and their morphology in the solder joint with Sn-3.0Ag-0.7Cu-5.0In (mass%) lead-free solder was investigated. As the substrate, the Cu plate and the Cu plate with electroplated Ni were prepared. Bonding was conducted in the vacuum atmosphere, and bonding temperature and time were 300°C and 10 minutes, respectively. The cooling rates in the bonding were changed from 0.02°C/s to 0.2°C/s. In both Cu/Cu and Cu/Ni joints, scallop-shaped IMCs form at the joint interfaces regardless of the cooling rate. In the Cu/Cu joint, Cu6(Sn,In)5 and Cu3(Sn,In) layers form at the joint interface. In the Cu/Ni joint, (Cu,Ni)6(Sn,In)5 and (Cu,Ni)3(Sn,In) layers form at the joint interface with Cu and the (Cu,Ni)6(Sn,In)5 layer forms at the joint interface with Ni. Die shear force of the Cu/Ni joints are a little larger than those of the Cu/Cu joints. Fracture occurs in the boundary between the scallop-shaped layer or the granular IMC layer and the layered IMC in both joints. The cooling rate from the peak temperature to solidification is an important factor to decide the shape of formed IMC. When the cooling rate is high and supercooling becomes large, formation of pillar-shaped IMCs occurs easily.

Finite Element Analysis of Embedded Parts with Big-Diameter Reinforcing Bar under Shear Force

2010 ◽  
Vol 452-453 ◽  
pp. 509-512
Author(s):  
Yao Guo Zhu ◽  
Qing Xiang Wang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Shear Force ◽  
Three Dimensional ◽  
Interaction Force ◽  
Internal Force ◽  
Shear Capacity ◽  
System Response ◽  
Element Analysis ◽  
Reinforcing Bar

Nowadays embedded parts which connect steel members with concrete structures have frequently emerged in civil engineering; however the existing design code for embedded parts cannot satisfy the increasing demand of engineering as it was derived from limited experiments. In the paper, a finite element study on embedded parts with big-diameter reinforcing bars under shear force is conducted. The aim of the study was to fully investigate the mechanical performances of embedded parts under shear force using a three-dimensional finite element analysis with the help of a commercial software ANSYS. Cross-section internal force of anchor bar, embedded part deformation, interaction force between anchor bar and concrete, and friction force were investigated in order to well know the system response. The results show that the shear capacity of embedded part obtained from finite element analysis is conservative.

Effect of Electrode Material on Joint Strength of Soldered Joints With Sn-Bi and Sn-Bi-Sb Lead-Free Solder Balls

2013 ◽  
Author(s):  
Akihiro Hirata ◽  
Ikuo Shohji ◽  
Tetsuyuki Tsuchida ◽  
Toshikazu Ookubo
Keyword(s):  
Shear Force ◽  
Lead Free ◽  
Joint Interface ◽  
Intermetallic Compound Layer ◽  
Lead Free Solder ◽  
Ball Shear ◽  
Joint Properties ◽  
Solder Balls ◽  
Plating Solution ◽  
Free Solder

The aim of this study is to investigate the joint properties of Sn-58mass%Bi and Sn-57mass%Bi-0.5mass%Sb low-melting lead-free solder balls on the electroless Ni/Au and Ni/Pd/Au plated Cu electrodes fabricated with a lead-free plating solution. Compared with the conventional Ni plating solution containing lead, the soldered joints with Ni/Au and Ni/Pd/Au electrodes fabricated with the lead-free plating solution showed comparable joint properties. In the joints with Ni/Pd/Au electrodes, ball shear force increased when the Pd layer is dissolved into solder by multi reflows. In both joints with Ni/Au and Ni/Pd/Au electrodes, a part of the Ni layer was dissolved into solder and thus the (Ni,Cu)3Sn4 intermetallic compound layer formed at the joint interface. Ball shear force decreased upon aging due to the growth of the (Ni,Cu)3Sn4 layer at the joint interface.

Effect of Added Elements on Microstructures and Joint Strength of Lead-Free Sn-Based Solder Joint Dispersed IMC Pillar

2016 ◽  
Vol 879 ◽  
pp. 2216-2221 ◽  
Author(s):  
Yawara Hayashi ◽  
Ikuo Shohji ◽  
Yusuke Nakata ◽  
Tomihito Hashimoto
Keyword(s):  
Solder Joint ◽  
Shear Force ◽  
Joint Strength ◽  
High Reliability ◽  
Bonding Time ◽  
Lead Free ◽  
Joint Interface ◽  
Lead Free Solder ◽  
Uniform Dispersion ◽  
Free Solder

To create a high reliability solder joint using IMCs dispersed in the joint, the joints with four types of lead-free solder were investigated. The joint with Sn-3.0Ag-0.7Cu-5.0In (mass%) has high die shear force compared to other joints investigated, and the joint with the Ni-electroplated Cu bonded at 300 oC for 30 min showed the maximum die shear force due to formation of a large number of fine IMCs. In the joint with Sn-0.7Cu-0.05Ni (mass%), uniform dispersion of a large number of IMCs was achieved, although the die shear force of the joint is lower than that of the joint with Sn-3.0Ag-0.7Cu-5.0In. In the joint with Sn-5.0Sb (mass%), a solder area was remained in the center of the joint although a large number of columnar IMCs form at the joint interface. The die shear force of the joint with Sn-5.0Sb increased with increasing the bonding time due to formation and growth of IMCs. In the joint with Sn-3.0Ag-0.5Cu (mass%), IMCs formed at the joint interface and did not disperse in the entire joint.

Corrosion characterization of reinforcing bar in existing RC structure

2008 ◽  
pp. 177-182
Author(s):  
M Iwanami ◽  
H Yokota ◽  
E Kato ◽  
H Hamada
Keyword(s):  
Reinforcing Bar ◽  
Rc Structure

The Application of Pseudolinear Equivalent System in the Deformation Analysis of RC Structure Members

2012 ◽  
Vol 204-208 ◽  
pp. 4629-4634
Author(s):  
Hai Xiang Yu ◽  
Xiao Yang Chen ◽  
Xue Yuan Wang
Keyword(s):  
Shear Force ◽  
Nonlinear Deformation ◽  
Bending Moment ◽  
Deformation Analysis ◽  
Equivalent System ◽  
Reinforced Concrete Structure ◽  
Rc Structure ◽  
Concentrated Forces ◽  
Equivalent Method ◽  
Differential Relationship

A pseudolinear equivalent method is proposed to analyze the nonlinear deformation of reinforced concrete structure member. In this method, the real moment of a bending member is transformed into equivalent moment by means of acquiring the bending moment-curvature relation of the section, and then the equivalent concentrated forces along the member are gained through the differential relationship between bending moment, shear force and distributed force. By this method, the problem of nonlinear system can be transformed into the problem of linear system. This method can analyze the deformation of RC structure members with constant or variant sections, which can be extended to analyze the nonlinear deformation of the structure members made of other kinds of engineering materials. The analyzed result given by this method fits the result attained from finite element method very well, which proves the feasibility of the model.

Transmembrane Calcium Influx Associated with von Willebrand Factor Binding to GP Ib in the Initiation of Shear-Induced Platelet Aggregation

1993 ◽  
Vol 69 (05) ◽  
pp. 496-502 ◽  
Author(s):  
Yasuo Ikeda ◽  
Makoto Handa ◽  
Tetsuji Kamata ◽  
Koichi Kawano ◽  
Yohko Kawai ◽  
...  
Keyword(s):  
Shear Force ◽  
Calcium Influx ◽  
Fold Increase ◽  
Intracellular Camp ◽  
Recombinant Fragment ◽  
Transmembrane Flux ◽  
Irreversible Aggregation ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Camp Levels

SummaryWe found that the binding of multimeric vWF to GP Ib under a shear force of 108 dynes/cm2 resulted in the transmembrane flux of Ca2+ ions with a two-to three-fold increase in their intracellular concentration ([Ca2+]i). The blockage of this event, obtained by inhibiting the vWF-GP Ib interaction, suppressed aggregation. In contrast, the blockage of vWF binding to GP IIb-IIIa, as well as the prevention of activation caused by increased intracellular cAMP levels, inhibited aggregation but had no significant effect on [Ca2+]i increase. A monomeric recombinant fragment of vWF containing the GP Ib-binding domain of the molecule (residues 445-733) prevented all effects mediated by multimeric vWF but, by itself, failed to support the increase in [Ca2+]i and aggregation. These results suggest that the binding of multimeric vWF to GP Ib initiates platelets aggregation induced by high shear stress by mediating a transmembrane flux of Ca2+ ions, perhaps through a receptor-dependent calcium channel. The increase in [Ca2+]i may act as an intracellular message and cause the activation of GP IIb-IIIa; the latter receptor then binds vWF and mediates irreversible aggregation.

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