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Anchor Drilling machine soil conservation
writer:ld-driller | time：2020-09-03 16:05:32

Anchor Drilling machine of Qianshan machinery after 7~8 days of soil cable anchor cable grouting maintenance, when the anchor strength is greater than 15Mpa and not less than 75% of the design strength, after the bearing capacity is confirmed, install the enclosure on the supporting structure, conduct prestressed tension. The Tensioning equipment is the same as the prestressed structure, and the prestressed value is 75% ~ 80% of the designed anchoring force.

Note the following matters during tension:

The tension should be separated by one; Before the formal tension of anchor cable, 10% ~ 20% of the designed tension should be taken, and cable anchor should be pre-tensioned for 1~2 times; The formal tension of anchor cable should be graded loading, after each level of loading, the load should be stable for 3min, and the elongation value should be recorded; Load step by step until 80% of the designed anchoring force, and the last level of loading should be stable for 5min, and the elongation value should be recorded; when there is no obvious attenuation of the tension bar, the tension bar can be locked; After the design tension is completed for a period of time, depending on the attenuation of the tension bar, some cable anchor can be appropriately overtensioned.