Experimental Investigation of the Static Behaviour of a Hole Drilled Steel Plate Reinforced with a Composite Patch

Abstract

This paper presents an experimental investigation of the efficiency of a carbon/epoxy composite patch for reinforcing a steel plate with a central hole, loaded in static tension. Patches were laminated on one‐side of the steel plate using the conventional hand lay‐up method. Common, low cost composite materials were used, in an effort to assess the effectiveness of a repair or reinforcement that could be executed in situ in the harsh marine environment of a ship by properly trained crew personnel. Various methods were investigated for the steel surface preparation before patch lamination and corresponding roughness measurements were performed. Strains were monitored at three different positions of the specimens. Despite the low stiffness ratio of the patch reinforcements, experimental measurements indicated an extension of the linear response of the specimens, a smoother transition to plasticity and an increase in the failure load ranging from 30% to 50%.

A review on composite patch repairs and the most important parameters affecting its efficiency and durability

“…In one-sided patches, the stiffness ratio should always be selected considering the obtained thickness for the patch in a way that does not cause too much bending and does not lead to early separation. 44 Increasing the patch thickness to 30% or 40% of the thickness of the main plate is helpful in reducing SIF. After that, due to increased bending, the SIF remains almost constant.…”

“…In Tsouvalis et al. 44 a large area was artificially crodded and a patch was used to reinforce it. The tolerable final load increased by 10% to 30% relative to the initial state.…”

The Effect of Hot Water Ageing on the Glass Fiber Reinforced Epoxy Composite

“…In literature, the adhesive patch bonds and the effects of environmental conditions on these bonds and composites have been experimentally examined in many studies. Especially the studies on using single-patch repair [1][2][3][4][5][6][7][8][9][10]12,14,15,17], the patch applied on specimen having hole damage at the center [1,2,15,16,19], repairing the damaged composite specime ns, and the effects of moisture/temperature on the composite specimens [21,24,[26][27][28]30] have a significant place in literature. Among the studies carried out on patch, Campilho et al [1,2] repaired the composite plate, which were holed at the center, by making use of patch on the single surface.…”

“…Charalambides et al [13] experimentally analyzed the damage behaviors of single patch-repaired composite plates, on which the patch is applied on only one side, caused from the external factors. Tsouvalis et al [15] examined the efficiency of steel plates, which have hole damage at the center and been repaired by using carbon/epoxy patch, under the static tensile load. They determined that the failure load rates of patches increased from 30% to 50%.…”