days. During most of this period the equipment was working on two 10 hour shifts allowing 4 hours for inspec- tion and servicing. In one calendar month more than one- half million (500,000) cu, yds. of dirt was moved with this outfit which exceeds any previous figure on similar jobs in the Philippines, if not the entire Far East.
The Tournapulls, with the help of the push tractors at the stockpile were used to haul the sand for the sub base from the stockpile and spread in place on the runways, taxiways and aprons. About 120,000 c.y. were placed in 67 working days for a daily average of 1,800 c.y.
Some 50,000 c.y. of the gravel base material was stock- piled at site because the sub-base could not be prepared at the time and tempo of the gravel haul. This stockpile material was also spread by the Tournapulls. The gravel spread in this fashion in the base, compacted and finished better than the gravel that was delivered in place by truck and spread by the motorized graders.
All tractors used for excavating including those with scrapers, bulldozers and push blocks were Caterpillar, Model
Pneumatic Tired Wobble Wheeled Roller towed with Pneumatic Tired Tractor for final compaction,
Barber Greene Crawler Type paving machines.
Etnyre Distributor applying prime coat of asphalt.
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Caterpillar number 12 motorized grade: equipped with special 30' blade for preparing finished grade.
D-8, and the scrapers were Le Tourneau Carryalls, Model LP, 12 cu. yd. capacity. All of the scrapers, dozers and push blocks were cable operated from double drum power control units mounted on the rear of the D-8's.
Compaction Equipment
The primary units of modern compaction equipment are the sheepsfoot rollers with pressures of 130 lbs. per square inch used in various combinations to secure initial compaction in 6-10 passes over the fills, followed by the pneumatic tired wobble wheeled rollers having pressures exceeding 300 lbs. per inch width of tread. The sheepsfoot rollers were all built by Le Tourneau and towed by Cater- pillar tractors. The wobble wheel rollers were pulled with pneumatic tired tractors. Finish rolling of the fine grade and all bituminous concrete was rolled with two 3 wheel 10 ton Gallion rollers and four tandem 10 ton rollers of various makes.
Fine Grading
Five Caterpillar No. 12 Motorized Graders were in constant use to smooth and maintain the longitudinal grade and transverse slope of the cross section of the subgrade, subbase, and base materials. One of the graders was equipped with a special 30 foot blade in order to span the grade stakes and thus maintain the tolerances required in the specifications, eliminating all hand work in fine grading.
Drainage
Approximately two miles of reinforced concrete pipe is being installed in ditches for drainage of runway area. Excavation of ditches was accomplished with a Model 78 Northwest Dragline with a 1-1/2 cu. yds. bucket. Cats and scrapers were utilized in the wider ditches.
Processing Equipment
The rock crusher was shipped from the United States especially for this job. This plant could and did operate over long periods on a 100 ton per hour basis up to 16 to 20 hours per day. However, this rate could not be main- tained because the sub-contractor supplying the gravel to the crusher could not match this production.
The Crushing and Screening Plant comprised the following equipment and both the primary and secondary units are portable being mounted on pneumatic tired trailer units: 10" X 36" Jaw Crusher, 40′′ X 24′′ Roll Crusher, 4' X 12' Cedar-Rapids Vibrating Screen, 36′′ X 40′ Load- ing Conveyor, 30′′ X 60′ Feed Conveyor, 30′′ X 75' Stockpile Conveyor, and 30′′ Reciprocating Feeder.
The Primary Jaw Crusher, Screen, Conveyors, etc. are all electric driven from a 150 KVA Generator powered with Caterpillar D-17000 Diesel. The secondary Roll Crusher is driven with a Caterpillar D-13000 Diesel.
The Asphalt concrete mixer was rated for 3000 lbs. per batch and it was constantly averaging 100 tons per hour in the climate prevailing in Manila with one dryer. This plant was also shipped from the United States for this contract and is the only one of its kind in the Far East.
The Asphalt Mixer is a standard steel 40 cubic foot Pug Mill Type with a capacity of 150 tons per hour powered with a 150 H.P. Cummins Diesel motor.
It is a batch type plant with the aggregate and asphalt both weighed on beam type scales resulting in a very accurate control of the mix. The plant is equipped with thermo-
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