Concrete that has failed in compression (or tension)possesses the property of healing, providing the fractured parts are maintained damp and in intimate contact. The experimental work described in this paper was carried out to ascertain if any quantititive results could be found concerning healing in compression and how it was connected with the general hardening process in concrete. Only one mix of concrete was used and initial tests were made to ascertain the most suitable degree of failure for specimens to be healed. Concrete cylinders 5 in. dia. x 1O in. high were used. A series of these was tested at varying ages and re-tested after further periods of curing. Load-compression (or deformation) curves were taken for each test. It was found that the healing followed the same form as the general hardening process in concrete and it is thought probable that the healing is dependent upon the damage sustained by the initial compression test. A possible law for the deformation of concrete up to the point of failure is suggested for ordinary and healed concrete. Finally, practical consideration is given to the healing process in everyday site work. E.F. Whitlam
The Council regret to announce the deaths of Professor JOHN ORR (Honorary Associate); STANLEY JOHN BRUFORD, FREDERICK MILTON-COLE (Retired Members); GILBERT JAMES CUBBAGE, JOHN F. CUBBON, D.S.O., M.C., Major WILLIAM RICHARD SIMISTER (Members); ERIC GAYLMER LYTTON-ANDERSON (Associate-Member); JOHN ALEXANDER C,ALLARD (Graduate).
Mr. SEFTON JENKINS, presenting his paper, said he believed that Professor Magnel’s paper on prestressed steel, published in 1950, was the first that had been published on the subject. Professor Magnel had said that he would very much have liked to be present at the meeting, but he had been to America and would not get back to Belgium until the following day. Mr. Jenkins was grateful to him for having sent a photograph and some figures for his use.
The CHAIRMAN introduced Mr. Crispin, who then presented his paper. He also exhibited two cinematograph films illustrating soil stabilisation one (in colour) by permission of the Ministry of Works, and the other (in black and white) was shown by courtesy of Messrs. A. Monk & Co., Ltd.