Abstract
Cracks of buildings sometmes cause trouble between the persons concerned with their construction and design regarding the assignment of its responsibility. But it is often uncertain that those cracks exceed the inevitable amount in comparison with the other same sort of buildings. So in this paper we propose the method of quantitative expression about cracks in each building elements in order to clear the quantity, the form, the cause of cracks and to warn the structural danger or the leaking of water. In the investigation of cracks we use the easily movable nets fitted with the aluminum frame, measure the width and the frequency of cracks intersect threads of the net. The results obtained is shown in the figure of the frequency-width curve and the cumulative frequency curve. This figure is our proposed expression as the crack-quality curves. And also we show effectiveness of this method not only in reinforced concrete structure but also in other structure by applying to about 13 buildings and comparing quantities, distributions of width, the progress of cracks in each building elements of same use, and the characteristics of cracks of building made from different materials.
