| Popis: |
A study of the factors affecting the packing and porosity of particles has been made and a general theory for the combining of aggregates of varying shapes and sizes in order to achieve minimum porosity is proposed. Arising out of this theory experiments have been carried out from the results of which graphs have been prepared to enable the determination of the optimum percentage of fine material for maximum density in two component systems. A method for extending the application of these results into the province of the design of multicomponent systems of both the continuous grading and intermittent grading types has been devised, and in the latter type the inherent gaps in the grading have been related to measured void characteristics. From another graph the value of porosity appropriate to any such mixture can be estimated. The theory and relevant graphs are believed to be of general application in the fields of mixtures comprising aggregates of any shape or combination of shapes whether these be dry aggregates, wet aggregates, bitumen or tar coated aggregates or concrete aggregates, and to cover all possible environmental conditions of the particulate mass such as the applied compactive effort and boundary effects. |
