THE POZZUOLANIC PROPERTIES OF MEYCAUAYAN VOLCANIC 



TUFpi 



By Albert E. W. King 



{From the Laboratory of General, Inorganic, and Physical Chemistry, 



Bureau of Science, Manila, P. I.) 



ONE TEXT FIGURE 



During June, 1914, the Bureau of Science received for com- 

 pression test twelve 6-inch tuff (adobe stone) cubes taken from 

 the Tayawanak quarry, Cavite Province, Luzon. Similar ma- 

 terial was to be used in the construction of bridge abutments. 

 The specimens were exposed in air and tested for compressive 

 strength. Table I shows the results obtained. 



Table I. — Compressive strength of 



6-inch Tayawanak tuff 



cubes. 



Age. 



Total strength. 



Strength per square 

 centimeter. 



Strength per 

 square inch. 





















First 

 crack. 



Ultimate. 



First 

 crack. 



Ultimate. 



First 

 crack. 



Ultimate. 



First 

 crack. 



Ultimate. 



Days. 



KUos. 



Kilos. 



Lbs. 



Lbs. 



Kilos. 



Kilos. 



1,6s. 



Lbs. 



35 



1,315 



1,394 



29,000 



30,750 



56.66 



60.04 



806 



854 



S5 



645 



1,042 



12,000 



22,950 



23.41 



44.85 



333 



638 



35 



516 



1,262 



11,350 



27, 800 



22.14 



54.34 



315 



773 



35 



523 



1,098 



11,500 



24,200 



22.42 



47.31 



319 



673 



35 



882 



1,098 



19,400 



24,200 



37.82 



47.31 



638 



673 



36 



802 



925 



6,650 



20,350 



13.00 



39.79 



185 



566 



63 



999 



1,476 



23,000 



32, 500 



44.85 



63.48 



638 



903 



63 



1,184 



1,248 



26,100 



27, 500 



50.97 



53.71 



725 



764 



63 



908 



1,161 



20,000 



25,550 



39.09 



49.77 



656 



708 



63 



1,348 



1.348 



29,700 



29,700 



28.00 



58.00 



825 



825 



63 



1,549 



1,549 



34, 100 



34, 100 



66.65 



66.65 



948 



948 



63 



650 



1,057 



12,100 



23,300 



23.60 



45.48 



336 



647 



The material is very soft, porous, and fine-grained and as the 

 results show is not suitable for construction subjected to high 

 unit stresses. Cox - describes the occurrence and properties of 

 tuffs in general : 



volcanic sediments and pyroclastic tuflFs occur quite widely 



distributed in the Philippines. They are especially abundant in west central 

 Luzon, extending almost unbrokenly from near Lingayen Gulf to the sea- 

 coast of Batangas, practically blanketing or covering nearly all of the 

 massive rocks of this region. Mr. Ickis found volcanic tuff in the Agusan 

 Pulangi region, interior from Cagayan Misamis. 



In the absence of a better stone, in certain places this has been used 

 extensively for building purposes. In Bulacan and along the Pasig River, 



' Received for publication December 21, 1915. 

 ' This Journal, Sec. A (1908), 3, 393. 



19 



