ABSTRACT OF PROCEEDINGS. 



XXV11. 



500 fb per sq. inch. 



require any modification, but the following stresses are 

 recommended in the design of reinforced concrete struc- 

 ture : — 



Extreme fibre stress in concrete 

 in compression, c ... — 



Shearing stress and adhesion of 

 the concrete to the steel 

 reinforcement 



Direct compressive stress in 

 columns = 



Tensile stress in steel reinforce- 

 ments, f s = 16,000 



Compressive stress in steel re- 

 inforcements = 12,000 



Shearing stress in steel rein- 

 forcement = 10,000 



= 50 



350 



Ratio of 



E, 



15. 



Fundamental equations in rectangular beams : — 



-it- = f'P 



2 

 c 



I 



M 



bh* 

 x = 



(i) 



- *i 

 *. 



- f.p 



U - X 



Su — x 



(2) 



(3) 



V P w 



E a 



E a 



2p»-f- -P-grM 



Examples are given in the paper, also, of the application 

 of the conclusions arrived at to tee shaped beams. 



2. " The Occurrence of Inclusions of Basic Plutonic Rocks 

 in a Dyke near Kiama," by O. A. Sussmilch, f.g.s. 



The specimens described were obtained from the Bombo 

 Quarries, about 2 miles north of Kiama, and consist of 

 rounded fragments of basic and ultra-basic plutonic rocks 

 embedded in a dyke rock. The following plutonic rocks 



