Do you have any information concerning the recent collapse of a cast-in-place reinforced concrete high-rise apartment building near Washington, D C.? The incident involved major toss of life.
Not all mistakes in Washington are made by government officials. A report to the Commonwealth of Virginia by a consulting engineer has been quoted by the National Ready Mixed Concrete Association (NRMCA) because it gives some preliminary findings on this failure. Final determinations have not yet been established, however, on this collapse which killed 14 workers and injured more than 30. According to NRMCA, a 60-foot section of Skyline Plaza North in Bailey's Crossroads, Virginia, collapsed on Friday, March 2, 1973. One crane located in the destroyed area came down through the building, the floors of which were eight inches thick. The developer, the concrete contractor and the job superintendent have been indicted but responsibility has not been established. The possible cause of the failure "appears to be premature removal of shores between twenty-second and twenty-third floors in the area known as 'Pour Number Three.' Unassisted by shoring to the twenty-second floor, the concrete on the twenty-third floor had not obtained sufficient strength to carry the load imposed upon it.... Testing services reports indicate that most of the concrete specimens under laboratory conditions attained the specified 28-day compressive strength of 3000 psi. From mid-December, 1972 to March 2, 1973 the exceptions for lightweight concrete occur on samples taken from concrete intended for use outside the collapsed area."