Less than 100 pounds of nitroglycerin-based explosives are expected to be used to bring down the remains of the bomb-wrecked Alfred P. Murrah Federal Building in Oklahoma City, the Baltimore County-based Controlled Demolition Inc. said yesterday.
Outlining his company's plans for the demolition job that is expected to take place this weekend, Doug Loizeaux, vice president of CDI, said the entire implosion process should take about eight seconds -- but only after the considerable preparations that are under way.
Explosive charges strategically placed in about 220 locations in columns and walls on several levels of the building will be detonated in sequences lasting five seconds, to control the fall of the structure.
Explosives will be used to sequentially eliminate selected columns or supports to allow the weight of the building to fall in a northerly direction.
Before that happens, CDI will almost have to rebuild or strength- en some sections of the building weakened by blast damage -- placing additional cables and shoring up the structure to make it safer for demolition, said Mr. Loizeaux, who was at the site for a week supervising the preparations.
Because the damaged streets, sidewalks and utilities near the building are to be replaced, no extraordinary measures will be taken to protect them, said Mr. Loizeaux, adding that the implosion is being planned to avoid damage to nearby properties.