Construction Solving looksfam
Find the swell of a soil that weighs 1661 kg/m ³ in its natural state and 1186 kg/m³ after excavation.
40%
Find the shrinkage of a soil that weighs 1661 kg/m³ in its natural state and 2077 kg/m³ aftercompaction.
20%
A soil weighs 1163 kg / L * m ^ 3 (loose cubic meter),1661 kg/Bm^3 (bank cubic meter), and 2077kg/Cm^3 (Compacted cubic meter). How manybank cubic meter (Bm^3) and compacted cubicmeter (C * m ^ 3) are contained in 593,300 L * m ^ 3 ofthis soil?
Hint:
Bank Volume = Loose cubic meter x Load Factor
Compacted Volume = Bank cubic meter x Shrinkage Factor
Bank cubic meter = Loose cubic yard x LoadFactor
Compacted cubic meter = Bank cubic meter xShrinkage Factor
Bank Volume = 415,310.00 Bm^3 Compacted Volume = 332,248.00 Cm^3
Find the base width and height of a triangularspoil bank containing 100 BCM(76.5 BCM) if thepile length is 30 ft (9.14m) , the soil's angle of repose is 37°, and its well is 25%.
B = 7.45m H = 2.8m
Find the base diameter and height of a conical spoil pile that will contain 76.5 BCM of excavation if the soil's angle of repose is 32° and its swell index is 12%.
D = 10.16m H = 3.17m
Find the volume (bank measure) of excavation required for a trench 0.92 m wide, 1.83 m deep, and 152 m long. Assume that the trench sides will be approximately vertical.
255 BCM
Estimate the actual bucket load in bank cubic meters for a loader bucket whose heaped capacity is 3.82m ^ 3 The soil's bucket fill factor is 0.90 and its load factor is 0.80.
2.75 BCM
Find the expected production in loose cubic
meters (L * m ^ 3) per hour of a small hydraulic excavator. Heaped bucket capacity is 0.57m ^ 3 The material is sand and gravel with a bucket fill factor of 0.95. Job efficiency is 50min / h Average depth of cut is 4.3 m. Maximum depth of cut is 6.1 m and average swing is 90°.
Hint:
Production (LCH/h) = CxSxVxBxE
Cycle output = 250cycles/60 * min
Swing-depth factor = 1
113 LCM/h
Find the expected production in loose cubic meters per hour of a 2.3m ^ 3 hydraulic shovel equipped with a front-dump bucket. The material is common earth with a bucket fill factor of 1.0. the average angle of swing is 75° and job efficiency is 0.80.
Hint: Production (LCMh) = CxSxVxBxE
Cycle output = 150cycles / h
Swing = 1.05
290 LCM/h
Determine the expected dragline production in loose cubic meters (LCM) per hour based on the following information: Dragline size = 1.53m³
Swing angle = 120 deg Average depth of cut = 2.4m
Material = common earth
Job efficiency = 50 min / h Soil swell = 25%
Hint: Expected production = Ideal output x
Swing-depth factor x Efficiency
Ideal output xt = 176B /h
Swing-depth factor - 0.9
165 LCM/h
Estimate the production in loose cubic meters per hour for a medium-weight clamshell excavating loose earth. Heaped bucket capacity is 0.75m ^ 3 The soil is common earth with a bucket fill factor of 0.95. Estimated cycle time is 40 s. Job efficiency is estimated at 50min / h
53 LCM/h
A wheel tractor-scraper weighing 91 t is being operated on a haul road with tire penetration of 5 cm. What is the total resistance and effective grade when the scraper is ascending a slope of 5%?
Hint: RRF =20+(6 x cm penetration) GRF = 10 x grade (%)
9100 kg & 10%
A crawler tractor weighing 36 t is towing a rubber- tired scraper weighing 45.5 t up a grade of 4%. What is the total resistance of the combination if the rolling resistance factor is 50kg / (t')
5535 kg
A four-wheel-drive tractor weighs 20,000 kg and produces a maximum rimpull of 18,160 kg at sea level. The tractor is being operated at an altitude of 3050 m on wet earth. A pull of 10,000 kg is required to move the tractor and its load. Can the tractor perform under these conditions?
Hint:
Maximum usable pull = Coefficient of tractor x Weight on drivers Derating factor = [Altitude (m) - 915 ]/102
Coefficient of traction = 0.45
Because the maximum pull as limited by traction is more than the required pull, the tractor can perform under these conditions.
A power-shift crawler tractor has a rated blade capacity of 7.65 LCM. The dozer is excavating loose common earth and pushing it a distance of 61 m. Maximum reverse speed in third range is 8 km / h Estimate the production of the dozer is job efficiency is 50min / h
Hint: Production = Volume per cycle x Cycle per hr
Fixed time = 0.05 min Dozing peed = 4km / hr
271 LCM/h
Estimate the hourly production in loose volume (LCM) of a 2.68m ^ 3 wheel loader excavating sand and gravel (average material) from a pit and moving it to a stockpile. The average haul distance is 61 m, the effective grade is 6%, the bucket fill factor is 1.00, and job efficiency is 50 min/h.
Hint: Production = volume x cycle per hour
Fixed time - 0.50 min
Variable time - 0.3 min
178 Lm³ /h
The estimated cycle time for a wheel scraper is 6.5 min. Calculate the number of pushers required to serve a fleet of nine scrapers using single pushers. Determine the results for both back-track and chain loading methods.
Hint:
Number of scrapers served = Scraper cycle time / Pusher cycle time
Number of pushers required = Number of scrapers/Number served by one pusher
Pusher cycle time = 1.5 min (Back-track) & 1.0 min (Chain)
2 and 3
Find the expected production of the scraper fleet of the previous problem if only one pusher is available and the chain loading method is used. Expected production of a single scraper assuming adequate pusher support is 173 BCM/h.
Hint:
Production = [No. of pushers/Required number] x No. of scrapers x Production per scraper
1112 BCM / h
Given the following information on a shovel/truck operation, calculate the number of trucks theoretically required and the production of this combination.
Shovel production at 100% efficiency = 283 BCM/h
Job efficiency = 0.75
Truck capacity = 15.3 BCM
Truck cycle time, excluding loading = 0.5h
Hint:
Load Time = Haul unit Capacity / Loader production at 100% efficiency
Number of haulers required (N) = Haul unit cycle time / Load Time
11 trucks and 212 BCM/h
24.1 km of gravel road require reshaping and leveling. You estimate that six passes of a motor grader will be required. Based on operator skill, machine characteristics, and job conditions, you estimate two passes at 6.4km / h , two passes at 8km / h and two passes at 9.7km / h If job efficiency is 0.80, how many grader hours will be required for this job?
Hint:
Estimating Grader Production Time(h)
= [sum (Numberofpasses x Sectionlength(km))/(Averagespeed for section(km / h)] * 1/(Eff)
23.1 h
Trial blasting indicates that a rectangular pattern of drilling using 7.6-cm holes spaced on 2.75-m centers and 6.1 m deep will produce a satisfactory rock break with a particular explosive loading. The effective hole depth resulting from the blast is 5.5 m. Determine the rock volume produced per meter of drilling.
Hint: Volume / m = Volume per hole (m³) / Drilled hole depth (m)
6.8 m³ / m
A jaw crusher is producing 227 t/h of crush gravel and discharging it onto a three-scre deck. The top screen in the deck is a 38-m screen. The gradation of crusher output sho 100% passing 76 mm, 92% passing 38 mm, a 80% passing 19 mm. Material weight is 18 kg / m * 3 Find the minimum size of the 38-m screen to be used. Check both total screen la and screen passing capacity. Hint:
Basic capacity:
Total feed = 62t / h / (m²)
Passing screen = 34t / h / m²
Deck position factor (top) = 1 Half-size factor (80%) = 1.8
Oversize factor (8%):
Total feed = 0.96 Passing screen = 1.04
Weight Factor = 1.15
2.9 m³
[NOV 2022)
Calculate the volume of plastic concrete that will be produced by the mix design given in the table.
Component Sp.Gr Quantity
Cement 3.15 154
Sand (SSD) 2.65 426
Gravel (SSD) 2.66 549
WATER 1.00 95
0.51 m³
Determine the actual weight of each component to be added if the sand contains 5% excess moisture and the gravel contains 2% excess moisture.
Component Sp.Gr Quantity
Cement 3.15 154
Sand (SSD) 2.65 426
Gravel (SSD) 2.66 549
WATER 1.00 95
Water = 63kg
Sand = 447kg
Gravel = 560kg
Determine the weight of each component required to make a three-bag mix and the mix volume.
Component Sp.Gr Quantity
Cement 3.15 154
Sand (SSD) 2.65 426
Gravel (SSD) 2.66 549
WATER 1.00 95
Cement, 127.8 kg
Sand, 370 kg
Gravel, 464 kg
Water, 52 kg
Mix Vol, 0.42m³
Determine the weight of each component required to make a three-bag mix and the mix volume.
Component Sp.Gr Quantity
Cement 3.15 154
Sand (SSD) 2.65 426
Gravel (SSD) 2.66 549
WATER 1.00 95
Cement, 127.8 kg
Sand, 370 kg
Gravel, 464 kg
Water, 52 kg
Mix Vol, 0.42m³
Calculate the maximum hourly production of an asphalt plant based on the data in the following list.
Mix composition:
Asphalt = 6%
Aggregate composition:
Coarse A = 42%
Coarse B = 35%
Sand = 18%
Mineral filler = 5%
aggregate moisture = 8%
Dryer capacity at 8% moisture removal =110ton / h
Hint:
Plant Capacity (Dryer Capacity x 10⁴ ) /
(100-asphalt%) (100-fines%)
123 ton/h
Using the driving data below, determine the safe load capacity of a 6-in.-square concrete pile 60 ft long. Assume that the unit weight of the piles is 150 lb/cu ft.
Pile driver energy = 14000ft - lb
Ram weight = 4000 lb
Weight of driving appurtenances = 1000lb
Average penetration last six blows = 1/5 in/blow
Hint: K = 0.2
R=( 2E / S+0.1 ) { (Wr + KWp)/(Wr+ Wp)}
59,862 lb
Calculate the safe load capacity of a bulb pill based on the following driving data.
Hammer welght = 3tons
Height of drop = 20ft
Volume in last batch driven = 5 cu ft
Number of blows to drive last batch = 40
Volume of base and plug = 25cuft
Selected K value = 25
Hint:
L = ((W x H x B x V⅔))/K
164 tons
Determine the design lateral force for the slab form 152 mm thick, 6.1 m wide, and 30.5 m long. The slab is to be poured in one pour. Assure concrete density is 2403kg/m³ and that the formwork weighs 0.72 kPa.
Hint: H = 0.02 x dl x ws
1.46 kN/m