A double-lap single-bolt composite joint is designed as a model using the ANSYS finite element (FE) package. The joint is subjected to longitudinal tensile loads and half of the model is numerically analyzed. Three key factors influencing the performance of the connection are studied, including the bolt-hole fit, bolt pretightening force and the friction between the contacting plates. The model is then validated by several experiments, with computational errors of less than 10%. Analytical results show that a small magnitude of interference substantially improves the strength of the joints. With optimum interference, there is an increase of joint strength up to 36.5% as compared with the 3% clearance fit scenario. An adequate tightening torque also enhances the joint strength. The friction between the connecting laminates is also beneficial to increasing the strength. The failure mode varies with the friction coefficients between the plates for specific connection sizes. These findings signifies a beginning for the parametric analysis on load distribution uniformization in multi-bolted composite joints, which will be explored in subsequent studies.
ZHANG Qiliang
,
CAO Zengqiang
. Study on Factors Influencing the Performance of Composite Bolted Connections[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2012
, (4)
: 755
-762
.
DOI: CNKI:11-1929/V.20111202.1031.002
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