13th International Conference on Fracture June 16–21, 2013, Beijing, China fatigue test (2*104 or 105 cycles) + burst test of pipeline containing girth weld or seam weld or artificial discontinuity with „NOT PASSED” quality; burst test of operated (fatigued and replaced), externally reinforced pipeline containing girth weld with „NOT PASSED” quality; fatigue test (105 cycles) + burst test of externally or internally reinforced pipeline containing girth weld or artificial discontinuity with „NOT PASSED” quality. Clock Spring glass fibre reinforced PMC (CS), and own developed carbon fibre reinforced PMC (CFRPMC) were used for external reinforcing. The application of the Clock Spring composite sleeve reinforcing system can be found in the literature [13]. The installation of the own developed external reinforcing consists of five steps: cleaning and drying of the pipe; preparation of the reinforced area with resin; reinforcing with carbon fibre (tape); covering with polymer film; hardening using heat treatment. Own developed glass fibre reinforced PMC (GFRPMC) was used for internal reinforcing. The applied reinforcing technology was as follows: cleaning and drying of the pipe; proofing of the shell material; reeling up of the proofed shell onto packet; setting of the packet into the pipe; reinforcing using internal pressure; hardening. One pipeline section was prepared for strain-gage measurements in order to investigate the behaviour of artificial failures under internal pressure and to establish basic data for finite element (FEM) calculations. Fig. 1 shows the detail of this pipeline section (B_b8) with artificial longitudinal gouge, strain-gages and an extensometer (see Table 2 and Table 3, too). Figure 1. Pipeline section (B_b8) with artificial longitudinal gouge, strain-gages and an extensometer The important characteristics (girth or seam welds and the quality of the welding, types and measurements of the failures, reinforcing) of the investigated pipeline sections are summarized in -3-
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