Question

Question 10: [9 marks] (Start a new page) Estimate the cost of installing a timber shoring system for a trench 850 m long. 1.4 m wide and 1.1 m deep. The sheeting will be nominal 50 x 200 mm (actual 38 x 184 mm) lumber, 1.2 m long. Two horizontal rows of nominal 100 x 120 mm (actual 89 x 112 mm) wales, 1.4 m long will be placed on each side of the trench for the full length of the trench. Trench braces of nominal 100 x 120 mm (actual 89 x 112 mm) section size will be placed 1.6 m apart along each row of wales. The sheeting will be driven one plank at a time using an air compressor and a pneumatic hammer. Four labourers combined will install the sheeting at 5 pieces/hour and wales and braces at 6 pieces/hour. The following material costs will apply: sheeting $610.00/m3, wales $650.00/m3 and braces $6.60 each. The following equipment costs will apply: air compressor $21.30/hour and pneumatic hammer $8.30/hour. Labour costs are $32.40/hour for driving timber sheet piles and $28.50/hour for installing wales and braces. The actual working time is 50 minutes in each hour. (Start a new page)

Answer 1

ANS- non of braces reg in each - (850) = 532 blacaga val of Trench for shoring system = (850XA) XL = 1309 m3 сол , bo co, a ѕаах 6-со = $3506 JDY COC Total cost → (798480 + 18641+ 3586+ 4x 32.90*36506 L + 28.5 x 1470 cost of sheeting → 300 x 610 796490 $ no.4 meet yequired = 1309 0.03exo.164*12) + 10% of total hour of braces of wals and iacting ise. T34546+14980) x (2180103 15 601 pieces cart of instrumento nooog hour required for theeting = 31000 hour. efficiency of working - soy lw= 63.asy, only Beg. hour 31002 + 5304 (hour) extra = $170506 + 112432 $ 5882938 36506 hour. carry walls - (850 x 148 0.089 ) x 650 => 68841.5$ mong braces reqH (850X14X0-089) 7509 pieces (6.089XO.12x 14) no. of hour y 750g - = 1264 hour. OD)) Actual area. (due to efficiency = 12.64 + 177 of 1264 7 1478 four