Accession Number : ADA266005
Title : Investigation of Probable Causes of Cracking, Aircraft Weather Shelters, Kadena Air Base, Okinawa
Descriptive Note : Final rept.
Corporate Author : ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS STRUCTURES LAB
Personal Author(s) : Wakeley, Lillian D ; Johnson, Wayne G ; Harrington, Patrick T
Report Date : Apr 1993
Pagination or Media Count : 66
Abstract : The U.S. Army Engineer Waterways Experiment Station (WES) investigated the causes of cracking in roof slabs of aircraft weather shelters at Kadena Air Base, Okinawa. Cracking had been noted by the users beginning soon after the concrete portions of the shelters were constructed in 1989. Reinforcing was increased for shelters built subsequently, but the newer shelters also cracked. The WES investigated the potential causes of cracking attributable either to materials and mixture proportions of the concrete or to structural and materials response of the structure to conditions in the environment. Both groups of factors contributed to the observed cracking. The high water content, aggregate grading, and curing procedures made the roof-slab concrete more susceptible to drying shrinkage cracking, which apparently initiated most of the observed cracks. Subsequent propagation of cracks is attributed primarily to flexure along the column lines. The materials studies revealed no evidence of ongoing degradation of materials. Dynamic and static analyses likewise indicate that the shelters have not experienced significant structural deterioration.
Descriptors : *AIRCRAFT , *SHELTERS , *CRACKING(FRACTURING) , *CONCRETE , *STRUCTURAL ANALYSIS , TEST AND EVALUATION , AGGREGATES(MATERIALS) , AIR FORCE FACILITIES , DESIGN CRITERIA , OKINAWA , ROOFS , SHRINKAGE , HANGARS , DRYING , DETERIORATION , AIRPORTS , CURING , STRUCTURAL RESPONSE , MOISTURE CONTENT , STRUCTURES , WEATHER , CRACKS , DEGRADATION
Subject Categories : Ceramics, Refractories and Glass
Construction Equipment, Materials & Supplies
Structural Engineering and Building Technology
Distribution Statement : APPROVED FOR PUBLIC RELEASE