EXPEDIENT REPAIR OF ANDREWS AFB RUNWAY 01L/19R Air Force Research Laboratory Air Base Technology Branch AFRL/MLQC Tyndall AFB FL Randall W. Brown, PhD, PE Principal Engineer Airfields &Pavements Group

OVERVIEW Background Findings/Solutions Repair Process Summary Conclusions

EXPEDIENT REPAIR OF ANDREWS AFB RUNWAY 01L/19R Background

BACKGROUND KEY EVENTS: 2 FEB 99 AFRL/MLQC contacted by HQ AMC on behalf of 89 CES, Andrews AFB MD MAR 99 Ground Penetrating Radar (GPR) Investigation APR 99 Follow-on GPR Investigation Cone Penetrometer Testing (CPT) Video inspection of airfield culvert 9-20 AUG 99 Repair of “Dip” in Runway 01L/19R at Andrews AFB MD

PROBLEM: A 2” dip in Andrews’ runway 1L/19R (The Air Force One Runway) was causing operational problems, particularly for small aircraft. BACKGROUND

APPROACH: Identify the Source of the Problem Using: A) Ground Penetrating Radar B) Cone Penetration Testing C) Optical Scan of Drainage Culvert (1) Develop a Suite of Alternative Solutions Considering Cost, Runway Downtime, and Effectiveness (2)

EXPEDIENT REPAIR OF ANDREWS AFB RUNWAY 01L/19R Findings/Solutions

FINDINGS/SOLUTIONS FINDINGS: Water Infiltration Poor Backfill Material Leaking Underlying Culvert Loss of Fines Through Culvert Weakened Pavement Support Settlement

FINDINGS/SOLUTIONS ALTERNATIVES: SOLUTION SELECTED - FOAM JACKING: Reconstruction (1) Foam Jacking (By-product of FY 98 AFRL research) (2) “Do Nothing” (3) Reduced Downtime (Conservatively 50%) (1) Reduced Cost (Conservatively 50%) (2) Effective Based on Private Sector and AFRL/MLQC Data (3)

FINDINGS/SOLUTIONS KEY ELEMENTS Initial Slab Lifting Using Polyurethane Foam Deep Injection Stabilization (Compaction Grouting with Polyurethane Foam) Repair Leaking Culvert Final Slab Alignment Using Polyurethane Foam Route and Seal Joints

EXPEDIENT REPAIR OF ANDREWS AFB RUNWAY 01L/19R Repair Process

REPAIR PROCESS PRE-TREATMENT CONE TESTING

REPAIR PROCESS PRE-TREATMENT CONE TESTING

REPAIR PROCESS DRILLING INJECTION HOLES

REPAIR PROCESS SEVERITY OF THE RUNWAY “DIP”

REPAIR PROCESS PREPARATION FOR INITIAL LIFTING OF RUNWAY SURFACE

REPAIR PROCESS INITIAL INJECTION

REPAIR PROCESS PREPARATION FOR DEEP INJECTION

REPAIR PROCESS SOIL STABILIZATION THROUGH DEEP INJECTION

REPAIR PROCESS EXTRACTION OF COPPER TUBES

REPAIR PROCESS FINAL ALIGNMENT

EXPEDIENT REPAIR OF ANDREWS AFB RUNWAY 01L/19R Summary

SUMMARY ,172 lbs 2,500 lbs hrs hrs hrs hrs Fri 20 Aug 99, 2400 required completion Fri 20 Aug 99, 1030 actual completion holes injected deep injection foam slab lifting foam gross time available time lost due to ramp freezes net time available actual time working on airfield

EXPEDIENT REPAIR OF ANDREWS AFB RUNWAY 01L/19R Conclusions

CONCLUSIONS Estimated Savings (50%) Estimated Downtime Savings (60%) 12 days -- actual repair time using foam 30 days -- optimistic estimate for reconstruction

CONCLUSION KEEP HER FLYING!

EXPEDIENT REPAIR OF ANDREWS AFB RUNWAY 01L/19R Air Force Research Laboratory Air Base Technology Branch AFRL/MLQC Tyndall AFB FL Randall W. Brown, PhD, PE Principal Engineer Airfields &Pavements Group