Engineering and Contracting . Vol. XXIX. No. 5. days. At the expiration of 30 days \vctested it as follows: We planted it tirmlyin the ground 5 ft. deep. At 25 ft. dis-tance we planted a large cedar telephonepole. .^t the level of 21 ft. from theground we fastened a wire cable from onepole to the other, which is about the heightof a trolley wire. In the center of thiscable we suspended a barrel. Into thisbarrel we loaded steel rivets graduallyand watched results. The two poles be-gan to bend as the load was applied. Whenthe two were deflected about 21 ins. eachtoward the other I observed a sma
Engineering and Contracting . Vol. XXIX. No. 5. days. At the expiration of 30 days \vctested it as follows: We planted it tirmlyin the ground 5 ft. deep. At 25 ft. dis-tance we planted a large cedar telephonepole. .^t the level of 21 ft. from theground we fastened a wire cable from onepole to the other, which is about the heightof a trolley wire. In the center of thiscable we suspended a barrel. Into thisbarrel we loaded steel rivets graduallyand watched results. The two poles be-gan to bend as the load was applied. Whenthe two were deflected about 21 ins. eachtoward the other I observed a small checkcome in the concrete pole about 10 the ground, and simultaneouslychecks appeared from the cable to theground. We immediately stopped loading,took off the ballast, weighted it and calcu-lated the horizontal strain and found itto be 975 lbs. The maximum momentwould be at the ground, but the guess atsize we made was about right, since theconcrete cracked from ground to cable atalmost the same time. When the load. Enq-ContrFig 5—Diagram of Reinforcement for 32-Ft. Pole. Bill of Material. Item. Dbs. 4 pes. Vi in. X 32 ft. twisted steel bar. pes. Va in. x 24 ft. twisted steel bar. pes. % in. X 16 ft. twisted steel bar. 20 pes., total weight of steel Concrete. cu. ft Approximate weight pole 2, Surface area steel sq. in. Base area steel sq. in. was removed the pole resumed its plumbposition and remains so today, althoughbeing used for heavy guy wires. Thebolts were unscrewed before moving them,leaving the nuts imbedded in the concrete set we screwed the boltsinto the nuts and could not loosen themwith an ordinary wrench. It took sev-eral heavy blows with a sledge hammer tobreak out the top socket. My conclusionswere, however, that a wire ring or twoof reinforcement should be placed aboutthe pin for safety. Careful estimates weremade as to cost of such a pole 35 ft. longif made in quantities in proper fo
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