1、Lessons Learned Entry: 1373Lesson Info:a71 Lesson Number: 1373a71 Lesson Date: 2002-01-28a71 Submitting Organization: DFRCa71 Submitted by: Roy TryonSubject: Construction Safety Abstract: Unavailable.Description of Driving Event: DFRC had a dozen large diameter (20“+/-) fire water sectional valves l
2、ocated in large vaults around the flight line. The requirement was to backfill these vaults with earthen materials, and remove the top of the vaults, and pave flush around them for minimal impact to the flight line area. The problems of doing this with “dirt“ included working down in deep confined s
3、paces, substandard compaction, hazards and probabilities of using power compactors around critical facility pressurized piping, and possible pipe damage resulting in flooding and drowning hazards. The simple solution arrived at was to “pour“ in pea gravel, that flowed in like water and achieved near
4、-100% compaction.Lesson(s) Learned: Pea gravel is the best material for backfill with instant compaction in hazardous or confined spaces.Recommendation(s): Consider and use pea gravel for backfill in hazardous or confined spaces. Evidence of Recurrence Control Effectiveness: N/AProvided by IHSNot fo
5、r ResaleNo reproduction or networking permitted without license from IHS-,-,-Documents Related to Lesson: N/AMission Directorate(s): a71 Exploration Systemsa71 Aeronautics ResearchAdditional Key Phrase(s): a71 FacilitiesAdditional Info: Approval Info: a71 Approval Date: 2004-01-08a71 Approval Name: Bart Henwooda71 Approval Organization: DFRCa71 Approval Phone Number: 661-276-5746Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
