Design and analysis of bolted joint connections in composite structures

.<Composite materials are used extensively in structures whose major designrequirements are high strength-to-weight and high stiffness-to-weight ratiosas the aircraft and the automotive structures. Mechanically fastening jointsremain the primary means of joining composite components in modemaircraft structures, due in part to need for disassembly, inspections andrepair. The high stress concentration at the contact between the bolt and thehole and the nature of the composite material itself give the research inbolted joint in composite structures great importance through the recent 30years.Most of the previous studies were experimental studies to find out the effectof various joining and geometrical parameters upon the bearing strength ofthe laminated composite plate. Most of the numerical models, found in theliteratures, are two dimensions in combination with a certain laminationtheory and failure criteria to find out the effect of joining and geometricalparameters on the stress state and even on the bearing strength.The main objective of our study is to exploit an existing numerical modelwhich has the capability of predicting the bearing strength for the compositebolted joint problem. Then check our model to a real case. The overall workaccomplished in three steps.The first step of our work is an experimental work. Through theexperimental work a laminate with [0/90hs stacking sequence wasmanufactured, cut into bolted joint specimens, and tested. In parallel, aunidirectional laminate with [Oh stacking sequence was manufactured, cut