Formwork System – Article Example
Introduction Cases of concrete structures collapsing while under construction have been taking place ever since concrete started being put in formwork. Causes and cases of such kind of structural failures have been recorded as well as documented in several journals, articles and texts. This report will focus on collapse of a 16 storey building that took place on 25th of January 1971 at 2000 Commonwealth Avenue in Boston, MA (Nawy, 2008).
The project-The apartment structure was made up of cast-in-place with a reinforced concrete level slab having a middle elevator shaft. Generally this sort of construction is common with buildings having multi-stories since they only need a minimal slab width which lessens the general elevation of the building. The 2000 Commonwealth Avenue building had a design of 16 stories inclusive of a mechanical room on top of a 5-foot crawl space on its roof. In addition, the building also comprised of 2 levels of basement parking. The first floor comprised of ancillary spaces, swimming pool together with one apartment, whereas the 2nd up to 16th floor had 132 apartments (Nawy, 2008).
Type of form/structure-The method used in construction was that of a level plate waffle slab having solid slabs at its column caps. This was actually the very first time motorized buggies were used in pouring of such a structure as this. Thus the collapsed floor was the 1st one above grade propped up on 2 tiers of shores totaling 22’ high. The weight of the buggies was 3000 lb loaded having been run at 12mph.There was a total of 8 buggies when the structure failed with approximately 500 cubic yards of concrete having been placed already. Investigations later laid the blame exclusively on insufficient prerequisites in the formwork to defy lateral forces.
Cause of failure
The failure was due to the following problems; engineers’ structural specifications were not followed, there was no concrete design strength as well as shoring and if present, it was removed quickly. In addition, reinforcement was improperly placed, minimal control of construction site, lack of engineering or architectural inspection done and finally the city of Boston did not provide adequate inspection (Nawy, 2008).
Consequences-The collapse resulted in the death of 4 workers and 20 others injured. There was also destruction and loss of building materials and other resources.
In conclusion, several lessons can be learnt from this failure such as the importance of adhering to building controls at every stage of construction. If adequate measures were implemented to ensure that original and proper design was followed, failure would not have taken place (Nawy, 2008).
Edward, N. (2008). Concrete Construction Engineering Handbook. New York: CRC Press.