Current Topics

Insulating Pipes from Vibration and Deformation Pipes (gas, water and others) carried by bridges, sheathed tunnels or other metal structures commonly rest on stands or are suspended by means of stirrups. In neither case is there adequate insulation from the carrying structure, consequently the pipes are subjected to the influence of vibration, and, still more serious, to be disjointed owing to deformation of the carrying members. To mitigate both these accidents it is suggested that stirrups should he suspended by means of springs, and that in special cases a spiral spring should be interposed between the crown of the pipe and the structural member immediately above it. When pipes are carried in cradles, springs can be inserted in the rests to act as buffers or cushions. (Deutsche Bauzeitung, No. 58.)

IN calculating the bending moments in a beam freely supported at the ends it is usual, when the loading is not symmetrical, first to calculate an end reaction. Many people do not realise that the calculations can be put in such a form that the complete bending moment and shear diagrams can be drawn without further calculation. W.A. Green

II. Materials, Methods of Testing and Tests PORTLAND cement was used which passed the standard tests for specific gravity, fineness, soundness and time of setting. The specific gravity was 3.10. J. Singleton-Green