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| Risk event (no.) | Occurrence likelihood | Economic losses | Casualties | Construction delays | Environmental impacts | Social impacts | Risk value |
|
| Ground wall invasion limit (1) | 3 | 4 | 3 | 2 | 3 | 3 | 10.2 |
| Equipment overturn (2) | 1 | 4 | 1 | 3 | 3 | 5 | 3.5 |
| Insufficient verticality (3) | 2 | 4 | 5 | 4 | 4 | 5 | 8.5 |
| Bulge (4) | 2 | 1 | 1 | 1 | 2 | 3 | 2.7 |
| Equipment overturn (5) | 3 | 4 | 5 | 3 | 2 | 4 | 11.4 |
| Limit of enclosing pile (6) | 2 | 4 | 4 | 4 | 5 | 1 | 7.5 |
| Broken pile (7) | 5 | 1 | 5 | 2 | 1 | 1 | 8.2 |
| Ground deformation caused by reinforcement (8) | 1 | 4 | 4 | 4 | 1 | 1 | 3.3 |
| The curtain is not closed (9) | 4 | 4 | 2 | 2 | 4 | 1 | 12.7 |
| Encounter obstacles (10) | 1 | 2 | 2 | 1 | 4 | 1 | 2.0 |
| Ground deformation caused by reinforcement (11) | 1 | 3 | 3 | 4 | 2 | 4 | 3.1 |
| Encounter obstacles (12) | 1 | 4 | 4 | 4 | 5 | 4 | 4.1 |
| Water grade does not meet 1 m below the excavation surface (13) | 2 | 1 | 1 | 2 | 2 | 2 | 2.7 |
| Causes excessive deformation of the surrounding surface (14) | 5 | 1 | 3 | 3 | 3 | 2 | 9.2 |
| A water source channel is formed inside and outside the pit, unable to precipitate (15) | 5 | 1 | 2 | 4 | 1 | 3 | 8.6 |
| The support end face does not fit the continuous wall (16) | 3 | 3 | 2 | 2 | 2 | 1 | 7.2 |
| Support active head is too long (17) | 5 | 3 | 3 | 5 | 1 | 1 | 13.9 |
| Steel rafters are not tightly installed (18) | 1 | 3 | 4 | 5 | 3 | 4 | 3.5 |
| Prestress is not applied in a timely manner (19) | 1 | 1 | 1 | 4 | 2 | 1 | 1.5 |
| Too much or too little prestress is applied (20) | 4 | 3 | 5 | 2 | 3 | 1 | 11.7 |
| Prestress loss is not added in time (21) | 4 | 3 | 4 | 2 | 1 | 3 | 11.1 |
| Insufficient steel support reserves (22) | 1 | 1 | 3 | 1 | 2 | 2 | 1.5 |
| Excessive displacement of the envelope structure (23) | 3 | 1 | 5 | 3 | 2 | 4 | 6.6 |
| Pit bottom uplift (24) | 2 | 5 | 1 | 4 | 3 | 1 | 7.4 |
| Unsupported exposure time is too long (25) | 3 | 5 | 5 | 2 | 1 | 3 | 11.9 |
| Excavator crash support or support fall (26) | 1 | 3 | 2 | 3 | 4 | 1 | 2.8 |
| Excavation in layers and blocks without time-space effect, insufficient sloping (27) | 5 | 1 | 4 | 1 | 5 | 3 | 10.4 |
| Timely construction of cushion and floor (28) | 1 | 5 | 4 | 3 | 4 | 1 | 4.1 |
| Longitudinal soil instability (29) | 2 | 5 | 3 | 2 | 5 | 4 | 8.6 |
| Waterproof layer failure (30) | 1 | 4 | 2 | 2 | 2 | 4 | 3.3 |
| Irregular scaffolding (31) | 5 | 5 | 3 | 1 | 4 | 1 | 18.5 |
| Scaffolding centralized loading (32) | 3 | 2 | 2 | 1 | 4 | 1 | 6.0 |
| Insufficient formwork reinforcement (33) | 5 | 2 | 3 | 5 | 1 | 1 | 11.2 |
| Concrete pouring discontinuity (34) | 3 | 1 | 3 | 2 | 4 | 2 | 5.5 |
| Concrete curing is not timely (35) | 4 | 2 | 2 | 1 | 3 | 3 | 8.5 |
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