Title:
Cracks in Concrete
Author(s):
Byram W. Steele
Publication:
Journal Proceedings
Volume:
43
Issue:
2
Appears on pages(s):
629-634
Keywords:
none
DOI:
10.14359/8760
Date:
2/1/1947
Abstract:
Cracks in concrete that are irregular and uncontrolled are objectionable. If causes were better understood, the elimination of cracks would be less diffi-cult. Cracks are mainly due to one or more of the following causes: (I) lack of adequate investigation of all the ingredients involved; (2) lack of sufficient advance planning to obtain satisfactory results; (3) lack of team work in the human element involved in this intricate manufacturing process; and (4) lack of teamwork (compatibility) in the Ingredients which include alkali-aggregate reaction and the use of argillaceous limestone and chert as aggregate. The modern laboratory’s test procedure will not condemn many limestones and cherts that are capable of starting surface cracking. The elimination of unsound types is not at all a simple procedure. A suggested A-B-C procedure is offered toward the partial elimination of cracks: A. to qate with good establish approved sources service record: B. thorough aggregate investigatie new sources of supply subjecting them to all known tests including analysis by a petrographer; C. study the design of every structure proposed with a view towards eliminating structural cracks by proper control of the design of the mix and the placing of the concrete and provide relief from volume change tensile stresses, with designed cracks placed where they will not be objectionable.