دانلود رایگان مقاله لاتین مفاصل کامپوزیت از سایت الزویر


عنوان فارسی مقاله:

اثر آسیب در حالت شکست مفاصل کامپوزیت چند پیچ با استفاده از روش شکست انولوپ

عنوان انگلیسی مقاله:

Effect of damage on failure mode of multi-bolt composite joints using failure envelope method


سال انتشار : 2016



برای دانلود رایگان مقاله مفاصل کامپوزیتاینجا کلیک نمایید.





مقدمه انگلیسی مقاله:

1. Introduction

Composite materials have been extensively used in aerospace and many other industries. Due to limitations of manufacture and maintenance, bolted joints are quite commonly used in composite structures [1]. However, the drilling of holes cuts the fiber and causes local stress concentration, resulting in reduction of load carrying capacity. To ensure safety and increase weight saving effi- ciency, the joint structures must be designed seriously, and their mechanical behavior should be studied carefully [2–5]. The failure mode and strength are important properties for composite bolted joints. The main failure modes of multi-bolt joints include net-section failure, bearing failure and shear out failure as shown in Fig. 1. The bearing failure is a progressive process, while net-section failure and shear out failure occur immediately and catastrophically. The latter two failure modes may reduce the load carrying capacity or cause instant failure of the whole structure. That is the reason why bearing failure mode is preferred in joint structural design and the other two modes should be avoided. By adjusting ±45 layer ratio and the end distance of connected objects, shear out failure can be suppressed and the main failure modes are the other two failure modes. The control of failure modes is very important for bolted joint structure design, thus failure mode prediction methods of multi-bolt composite joints are needed to be investigated. Many researchers have investigated mechanical properties of single-bolt composite joints [6–8]. Compared with single-bolt joints, there are various load transferring paths in multi-bolt structures, causing more complicated structural characters. Current mechanical investigations on multi-bolt joints mainly focus on bolt load distribution [9–14] and predictions of failure modes and strength. The failure envelope method is a common accepted engineering method for failure mode and failure load prediction. The failure envelope method is originally proposed by HartSmith [15] to predict tensile and bearing failure of double-lap multi-bolt joints with quasi-isotropic or near-quasi isotropic layups. He found that a linear interaction exists between the bearing stress along the bolt hole and the remaining tension stress running by that hole to be reacted elsewhere (bypass stress). Based on the experimental results, he proposed the bearing-bypass failure envelope. Then, Crews and Naik [16], Rao et al. [17], Camanho et al. [18,19], Bois et al. [20] applied and developed the method. In the failure envelope, the line corresponding to bearing failure is a contour line determined by single-bolt bearing strength. But Liu et al.



برای دانلود رایگان مقاله مفاصل کامپوزیتاینجا کلیک نمایید.






کلمات کلیدی:

Predicting Failure in Multi-Bolt Composite Joints Using Finite Element ... https://www.scientific.net/KEM.293-294.591 by CT McCarthy - ‎2005 - ‎Cited by 13 - ‎Related articles Damage Assessment of Structures VI: Predicting Failure in Multi-Bolt Composite Joints ... diagrams to predict the failure load, mode and location for the joints. [PDF]Effects of Variable Clearance in Multi-Bolt Composite Joints on ... www.escm.eu.org/docs/eccm/B099.pdf by VP Lawlor - ‎Cited by 1 - ‎Related articles failure modes were found in the single-lap joints, while the double-lap joints ... damage caused to the composite during insertion of the fastener, and ... on the effects of clearance in multi-bolt joints, almost all have dealt with quasi-static loading. bearingbypass loading on bolted composite joints - NASA Technical ... https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19870016004.pdf by JH Crews Jr - ‎1987 - ‎Cited by 17 - ‎Related articles This failure mode appears to be unique to compression bearing-bypass. 1 ... Within multi-fastener joints, fastener holes may be subjected to both bearing loads ... damage modes were determined by radiographing each specimen after testing. [PDF]Failure Analysis of Bolted Composite Joint- A Review - IJETT www.ijettjournal.org/volume-11/number-10/IJETT-V11P294.pdf by R Gill - ‎Related articles Keywords— Bolted joint, composite, failure modes, finite element method ... the load distribution in multi-bolt joints and material damage propagation . Images for damage on failure mode of multi-bolt ... Image result for damage on failure mode of multi-bolt composite joints Image result for damage on failure mode of multi-bolt composite joints Image result for damage on failure mode of multi-bolt composite joints Image result for damage on failure mode of multi-bolt composite joints Image result for damage on failure mode of multi-bolt composite joints More images for damage on failure mode of multi-bolt composite joints Report images Composite Joints and Connections: Principles, Modelling and Testing https://books.google.com/books?isbn=0857094920 P Camanho, ‎Stephen R. Hallett - 2011 - ‎Technology & Engineering ... 441,497 damage criteria, 306–16 bolt joint, 312–16 critical damage, 315–16 ... 182 double-lap multi-bolt tests, 94–5 failure modes of two-bolt tension joints, ... [PDF]Multi-Fastener Single-lap Joints in Composite Structures - DiVA portal https://www.diva-portal.org/smash/get/diva2:10358/FULLTEXT01.pdf by J Ekh - ‎2006 - ‎Cited by 23 - ‎Related articles of BOJCAS - BOlted Joints in Composite Aircraft Structures, a RTD project par- ... could affect the load distribution if member plates with different thermal expansion ..... Increasing (e/d) up to 4 shifts the failure mode from shear out to bearing.