Influence of neighboring structures on the wind pressure on tall buildings

Measurements U'1f8 been made of the wind pressure over a model « the Empire State Building as affected by the presence of n~hboring mO'dels'Simulat ing btrildiup which mipt be erected on the adjacent blocks. Tire m,ject was to determine the shielding effect for different directions of the wind. . While the pressure on certain faces of the building was increased somewhat by the presence of the neishboring'structures, the resultant of pressure on the windward face and aumoD on the lee face was decreased. The decrease was greatest when the Interfering structure was close by and directly upstream. The height shielded was Dot so great as the height of the interfering structure. Shielding may produce a variation in the twisting moment about a vertical asis at different levels. The stresses set up by this loading may require con sideration in special cases.