Soil Strain Measurements on Misers Bluff. Phase II.
Abstract
Soil strain measurements were made on the MISERS BLUFF - Phase II tests. The first test, a 109 metric ton ANFO explosion, indicated that the tubular, telescoping strain gage with large end plates and a DC LVDT sensing element should be adequate to measure strains on the second test which was the detonation of six 109 metric ton ANFO charges on the corners of a 100 m hexagon. The strains observed on the second event were much larger than on the first event. Three locations were instrumental to 1.6 m in depth for vertical strain, two halfway between charges on opposite sides of the array and one 6 m from the array center. The strains were initially compressive due to air shock loading and then extensional during the negative phase. Extensional strains greater than 50% were observed at the 6 m location down to a depth of 0.9 m. The air shock loading at the locations between charges was not the same, nor were the soils identical. Strains of -12% to +30% were typical at near surface locations. The final or residual strain measured on recovery was usually compressive except at one location where the soil was very powdery. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 30, 1979
- Accession Number
- ADA079942
Entities
People
- R. A. Shunk