Title: Spirally Reinforced High-Strength Concrete Columns
Author(s): Salvador Martinez, Arthur H. Nilson, and Floyd 0. Slate
Publication: Journal Proceedings
Appears on pages(s): 431-442
Keywords: columns (supports); compressive strength; confined concrete; deformation;
high-strength concrete; lightweight concretes; loads (forces); reinforcing steels; short columns; spiral reinforcement.
Results are summarized of an experimental investigation to establish the response of high-strength concrete columns, confined with steel spirals, when subjected to short-term compressive loading. Main variables were compressive strength of the concrete, amount of confinement, and specimen size. The program included tests of 94 short columns of 4, 5, and 6 in. (102, 127, and 152 mm) diameter. Most were cast without protective concrete cover over the spirals, but 16 specimens with cover were included. The work included both normal weight and light weight concrete. Strength and deformation characterisfics are reported. Based on these test results, implications concerning use of high-strength concrete in spirally reinforced columns are discussed. It is shown that present design specifications, based on tests of columns using lower-strength concrete, may be unsafe under some conditions if extended to columns using high-strength concrete. Other questions are raised relating to the use of large diameter high-strength concrete columns and the use of lightweight concrete in columns.