SOME GENERALIZATIONS ON THE INFLUENCE OF SUBSTANCES 

 ON CEMENT AND CONCRETE ^ 



By J. C. Witt 



(From the Laboratory of General, Inorganic, and Physical Chemistry, 

 Bureau of Science, Manila) 



The great variety of uses which modern industry is finding 

 for concrete is continually presenting new problems for research 

 and likewise increasing the importance of work that was 

 completed at a time when the theoretical side was perhaps the 

 only one under consideration. I refer especially to the sensitive- 

 ness of cement to many substances and to the destructive chemical 

 action of some external agencies on concrete. The presence of 

 any one of a number of organic or inorganic substances in the 

 water or aggregates used in mixing concrete may seriously inter- 

 fere with the work or later result in its failure. Even after 

 concrete has been properly made and placed and the work has 

 not failed in either quality or design, it sometimes happens that 

 the construction is not permanent, because it comes into contact 

 with some destructive substance. 



This field of research is becoming more important year by 

 year, because of the many new demands being made on the 

 material. Sewer and drain pipe, storage tanks for various liq- 

 uids, and even boats are now made of concrete. Therefore it 

 is not surprising that the material should be called upon to resist 

 conditions which were not known a few years ago. These agen- 

 cies may be encountered in a number of ways. For instance, 

 a sewer pipe may be capable of resisting the ordinary substances 

 found in sewage, but may be injured by some industrial waste 

 material which has found its way into the drainage system. 

 Storage tanks may be constructed for a liquid in the belief that 

 they will be satisfactory, but later it may be found that the 

 liquid acts on the concrete, either injuring the tank or contam- 

 inating the liquid.^ 



It is highly desirable that as many substances as possible be 

 investigated in relation to their effect on cement, so that the 

 presence of harmful ones may be avoided in mixing concrete 



' Received for publication May 2, 1917. 



' Cf . Rohland, P., Beton u. Eisen (1914), 13, 341; Feuerungstechnic 

 (1914), 2, 360. Sartori, A., Chem. Zeitg. (1915), 39, 957. Hinzlemann, R., 

 Journ. Soc. Chem. Ind. (1904), 23, 995. 



29 



