Table 7 Steel grouting pipe pull-out test loading and unloading grade table.
Loading and unloading cycles | Load increment: percentage of ultimate tensile strength | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Cycle 1 | 10 | Â | Â | Â | Â | Â | Â | 30 | Â | Â | Â | Â | Â | 10 |
Cycle 2 | 10 | 30 | Â | Â | Â | Â | Â | 40 | Â | Â | Â | Â | 30 | 10 |
Cycle 3 | 10 | 30 | 40 | Â | Â | Â | Â | 50 | Â | Â | Â | 40 | 30 | 10 |
Cycle 4 | 10 | 30 | 40 | 50 | Â | Â | Â | 60 | Â | Â | 50 | 40 | 30 | 10 |
Cycle 5 | 10 | 30 | 40 | 50 | 60 | Â | Â | 70 | Â | 60 | 50 | 40 | 30 | 10 |
Cycle 6 | 10 | 30 | 40 | 50 | 60 | 70 | Â | 80 | 70 | 60 | 50 | 40 | 30 | 10 |
Cycle 7 | 10 | 30 | 40 | 50 | 60 | 70 | 80 | 90 | Â | Â | Â | Â | Â | Â |
Observation time(min) | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 15 | 5 | 5 | 5 | 5 | 5 | 5 |
