You are employed as a construction engineer on a new municip…

You are employed as a construction engineer on a new municipal recreation center project. The sitework phase includes excavation for a swimming pool and underground mechanical piping. Based on the design drawings, 6,000 bank cubic yards of soil must be excavated. Once the pool structure and utilities are complete, approximately 2,800 compacted cubic yards of material will be required for backfilling and grading. The excess soil will be transported off-site to an approved fill location. The average haul distance is 750 feet, with a 2% uphill grade. Laboratory tests on the soil samples provide the following data: Bank density = 2,600 lb/bcy Loose density = 2,150 lb/lcy Compacted density = 3,700 lb/ccy What is the percent swell for the soil? What is the percent shrinkage for the soil? How many bank cubic yards should be stockpiled to be used for backfill operation? How many loose cubic yards of soil should be hauled away to the disposal site?  

A single-phase two-winding transformer is rated 20 kVA, 480/…

A single-phase two-winding transformer is rated 20 kVA, 480/120 volts, 60 Hz. During a short-circuit test, where rated current at rated frequency is applied to the 480-volt winding (denoted winding 1), with the 120-volt winding (winding 2) shorted, the following readings are obtained: V1=35 volts, P1 = 300 W. During an open-circuit test, where rated voltage is applied to winding 2, with winding 1 open, the following readings are obtained: I2 =12 A, P2 = 200 W. Find the following: a. From the short-circuit test, determine the equivalent series impedance Zeq1 =Req1 + jXeq1 referred to winding 1. Neglect the shunt admittance. b. From the open-circuit test, determine the shunt admittance Ym = Gc jBm referred to winding 1. Neglect the series impedance.