QUANTITY-SURVEYING PRESENTATION-PRELIM.pptx

It's all about estimates in Civil Engineering

1. P R E L I M

2. 1.00 SPECIFICATION; PLANS AND DETAILS

3. 1.1 CONCEPTS OF QUANTITY SURVEY

4. QUANTITY SURVEY - THE SCHEDULE OF QUANTITIES OF ALL THE ITEMS OF WORK IN A BUILDING. IT IS THE CALCULATIONS OF QUANTITIES OF MATERIALS REQUIRED TO COMPLETE THE WORK CONCERNED ESTIMATE - THE ANTICIPATED OR PROBABLE COST OF WORK PREPARED BEFORE THE START OF CONSTRUCTION.

5. QUANTITY ESTIMATE - COMPLETE ESTIMATE OF QUANTITIES FOR ALL ITEMS OF WORK REQUIRED TO COMPLETE THE PROJECT. FACTORS TO CONSIDER IN MATERIALS ESTIMATE: QUANTITY QUALITY PRICES PRICE TRENDS SUPPLIERS DELIVERY TIME AND TRANSPORT COST AMOUNT TO BUY STORAGE REQUIREMENT

6. FACTORS TO CONSIDER IN LABOR ESTIMATE: SKILL LEVEL NUMBER REQUIRED FOR EACH SKILL EXPERIENCE DAILY RATES AVAILABILITY IN THE PROJECT LOCALITY FACTORS TO CONSIDER IN EQUIPMENT ESTIMATE: KIND OF EQUIPMENT FUEL CONSUMPTION RENTALS

7. CAPABILITY OF THE EQUIPMENT DAILY RATE OF EQUIPMENT OPERATOR NUMBER OF EQUIPMENT REQUIRED AVAILABILITY OF EQUIPMENT SUPPLIERS OF EQUIPMENT REQUIREMENTS FOR PREPARATION OF ESTIMATES: WORKING DRAWINGS TECHNICAL SPECIFICATIONS RATES - PRICES OF MATERIALS, RENTAL RATES EQUIPMENT, PREVAILING RATES OF LABOR

8. OTHER FACTORS: QUALITY OF MATERIALS AVAILABILITY OF MATERIALS TRANSPORTATION AND FREIGHT OF MATERIALS LOCATION OF SITE AVAILABILITY OF LABOR EQUIPMENT NEEDS AVAILABILITY OF EQUIPMENT KNOWLEDGE OF EXCEL SOFTWARE

9. 1.2 THE QUANTITY SURVEYOR

10. 1.3 BIDDDING PROCESS AND GENERAL PROJECT SPECIFICATIONS 1.3.1 GENERAL CONDITIONS 1.3.2 SPECIAL CONDITIONS 1.3.3 THE BID FORM 1.4 CONSTRUCTION PLANS AND DETAILS 2.2.1 ALL ARCHITECTURAL, STRUCTURAL, PLUMBING & DRAINAGE, ELECTRICAL, AND MECHANICAL DRAWINGS OF THE PROJECT. 2.2.2 ALL STRUCTURAL DRAWING DETAILS

11. ARCHITECTURAL PLANS:

12. REINFORCED CONCRETE STRUCTURAL DETAILS

13. TYPICAL R.C. BEAM STRUCTURAL DETAIL

14. STRUCTURAL STEEL DETAILS

15. 2.00 DETAILED QUANTITY SURVEY DETAILED QUANTITY SURVEY OR DETAILED ESTIMATE - INCLUDES ESTIMATE OF MATERIALS, LABOR, AND EQUIPMENT COSTS USED PER ITEM OF WORK IN A CONSTRUCTION PROJECT. COLLECTIVELY CALLED DIRECT COST.

16. 2.1 ESTIMATING DIRECT COSTS: CONSTRUCTION MATERIALS, LABOR, & EQUIPMENT

17. 2.1 CLEARING & GRUBBING 2.1.1 CLEARING & GRUBBING WORKS - MANUAL OR BY MACHINE (BULLDOZER OR GRADER). 2.1.1.1 MANUAL CLEARING & GRUBBING - LABOR COST & CLEARING TOOLS CAPABILITY OF LABOR: CLEARING UNDERGROWTH & TREES (12” Ø) - 0.05 M H / SQ.M. CLEARING UNDERGROWTH & SHRUBS - 0.03 M H / SQ.M.

18. 2.1.1.2 MACHINE CLEARING & GRUBBING - EQUIPMENT OPERATOR, LABOR, & EQUIPMENT RENTAL COSTS. EQUIPMENT: BULLDOZER: CLEARING - 500 SQ.M. / HOUR STRIPPING - 200 SQ.M. / HOUR PUSHING - 3 SQ.M. / HOUR GRADER: GRADING - 300 SQ.M. / HOUR SPREADING – 40 CU.M. / HOUR LABOR: COMMON LABORERS & EQUIPMENT OPERATORS MATERIALS : OIL AND FUEL

19. 2.2 DEMOLITION WORKS 2.2.1 MANUAL DEMOLITION - LABOR COST & DEMOLITION TOOLS ( SLEDGE, OXY-ACETYLENE WELDING, HAND HELD PNEUMATIC BREAKER ). TABLE 2.1 WORK ITEM - GENERAL DEMOLITION WORKS I T E M UNIT LABORER (M H) OPERATOR (M H) TOTAL (M H) WITH SLEDGE SQ.M. 3.24 - 3.24 WITH PNEUMATIC BREAKER SQ.M. 0.16 0.46 0.62

20. TABLE 2.2 WORK ITEM - DEMOLITION OF ELEVATED SLABS TABLE 2.3 WORK ITEM - DEMOLITION OF CONCRETE WALLS I T E M UNIT LABORER (M H) OPERATOR (M H) TOTAL (M H) WITH SLEDGE SQ.M. 16.24 - 16.24 WITH PNEUMATIC BREAKER SQ.M. 3.28 2.72 6.00 I T E M UNIT LABORER (M H) OPERATOR (M H) TOTAL (M H) WITH SLEDGE SQ.M. 14.41 - 14.41 WITH PNEUMATIC BREAKER SQ.M. 1.03 2.06 3.09

21. TABLE 2.4 WORK ITEM - REMOVAL OF CONCRETE CURBS TABLE 2.5 WORK ITEM - CUT CONCRETE OPENINGS I T E M UNIT LABORER (M H) OPERATOR (M H) TOTAL (M H) WITH SLEDGE L.M. 1.48 - 1.48 WITH PNEUMATIC BREAKER L.M. - 0.36 0.36 I T E M UNIT LABORER (M H) OPERATOR (M H) TOTAL (M H) WITH HAND CHISELS (7) CU. M. 18.34 - 18.34 WITH PNEUMATIC BREAKER CU. M. - 7.96 7.96

22. 2.3 EXCAVATION, BACKFILL, TRENCHING, & EMBANKMENT 2.3.1 ESTIMATING EXCAVATION - MANUAL OR BY MACHINE. MANUAL EXCAVATION: LABOR ONLY MATERIAL REQUIREMENT - NONE LABOR REQUIREMENT - COMMON LABORERS - CONSTRUCTION FOREMAN EQUIPMENT / TOOLS - SPADE; AUGER; DIGGING BAR

23. 2.3.2 MANUAL EXCAVATION - LABOR COST & EXCAVATION TOOLS (SPADES, AUGER, DIGGING BAR). COMMON EARTH (ESCOMBRO) - 8.00 M H / CU.M. LOAM OR SAND - 1.31 M H / CU.M. CLAY OR HEAVY SOIL - 1.64 M H / CU.M. ROCK - 2.63 M H / CU.M. 2.3.3 STRUCTURAL EXCAVATION - LABOR COST & EXCAVATION TOOLS (SPADES, AUGER, DIGGING BAR). COMMON EXCAVATION: BY HAND - 6.00 M H / CU.M. BY MACHINE - 0.50 M H / CU.M. ROCK EXCAVATION - 8.00 M H / CU.M. HAULING OF SPOILS - 1.00 M H / CU.M.

24. MACHINE EXCAVATION: MATERIAL REQUIREMENT - 0IL AND FUEL LABOR REQUIREMENT - COMMON LABORERS - EQUIPMENT OPERATORS EQUIPMENT / TOOLS - BULLDOZER; GRADER; / SPADE; DIGGING BARS

25. TABLE 2.5 EXCAVATION AND BACKFILL OPERATION EQUIPMENT CREW OUTPUT HAND EXCAVATION: - Light to Medium Soil SITE TOOLS 0.5 - Foreman 3 - Laborers 2 – 4 M 3 / Hr. - Heavy Soil to Rock SITE TOOLS 0.5 - Foreman 3 - Laborers 0.4 – 3 M 3 / Hr. 2. HAND TRIMMING SITE TOOLS 0.5 - Foreman 3 - Laborers 2 – 4 M 3 / Hr. 3. STRIP TOP SOIL: - Large Areas 105 HP Dozer 0.5 - Foreman 3 - Laborers 15 – 38 M 3 / Hr. - Small Areas 105 HP Dozer 1 - Operator 31 – 54 M 3 / Hr. EXCAVATE TO REDUCE LEVELS – Small Areas 105 HP Dozer 1 - Operator 31 – 54 M 3 / Hr. 5. SITE GRADING Motor Grader 1 - Operator 9 – 23 M 2 / Hr. BASEMENT EXCAVATIONS 1.15 m 3 Loader Dump Trucks 1 - Operator 0.5 – Laborers Truck Drivers 38 – 115 M 3 / Hr.

26. TABLE 2.5 - CONTINUATION OPERATION EQUIPMENT CREW OUTPUT 7. TRENCH EXCAVATION 0.58 m 3 Backhoe 1 - Operator 0.5 - Laborers 11 – 57 M 3 / Hr. EXCAVATION FOR PITS AND SUMPS 0.4 m 3 Backhoe 1 - Operator 0.5 - Laborers 8 – 23 M 3 / Hr.

27. 2.3.4 MACHINE EXCAVATION: COMMON EARTH (ESCOMBRO) - 6.67 M H / CU.M. ROCK W/ JACK HAMMER - 16.67 M H / CU.M. 2.3.5 EXCAVATING TRENCH: BY HAND - 6.00 M H / CU.M. BY MACHINE - 0.50 M H / CU.M. 2.3.6 TRENCHING & BACKFILLING: MANUAL EXCAVATION 0 to 2.0 m. DEEP - 1.25 M H / L. M. 2.0 to 3.0 m. DEEP - 1.67 M H / L. M.

28. 3.0 to 4.0 m. DEEP - 2.50 M H / L. M. 4.0 to 5.0 m. DEEP - 3.33 M H / L. M. MANUAL BACKFILLING PLACING BINDER GRAVEL - 0.11 M H / CU. M. ESCOMBRO BACKFILLING - 0.21 M H / CU. M. SPREADING, TAMPING, GRADING- 0.48 M H / CU. M. PLATE COMPACTION - 0.06 M H / CU. M. 2.3.7 BACKFILLING: BY HAND (COMMON BACKFILL) - 0.82 M H / CU.M. BY HAND (GRAVEL FILL) - 5.00 M H / CU.M.

29. 2.3.8 STRUCTURAL BACKFILL: BY HAND - 5.00 M H / CU.M. BY MACHINE - 2.00 M H / CU.M. 2.3.9 EXCAVATION W/ CRANE & CLAMPSHELL: WITH 8 MEN & 2 CARPENTERS - 1.07 M H / CU.M.

30. 2.4 FORMWORKS, SCAFFOLDINGS & STAging 2.4.1 MATERIALS FORMWORKS, SCAFFOLDINGS, & STAGINGS a) LUMBER FORMWORKS AND SCAFFOLDINGS b) METAL FORMWORKS AND SCAFFOLDINGS 2.4.1.1 LUMBER FORMWORKS AND SCAFFOLDINGS: FORMWORKS: 2 x 2 LUMBER AS FORM RIBS PHENOLIC BOARD OR PLYWOOD COMMON WIRE NAILS SCAFFOLDINGS: 2 x 3 OR 2 x 4 LUMBER FOR UPRIGHTS 2 x 2 LUMBER FOR BRACINGS 2 x 3 OR 2 x 4 LUMBER FOR LEDGERS AND SHORINGS

31. TIMBER SCAFFOLDS & FORMWORKS:

32. 2.4.1.2 METAL FORMWORKS AND SCAFFOLDINGS: FORMWORKS: PRE-FABRICATED WITH ANGLE BAR FRAMES AND METAL SHEETS SCAFFOLDINGS: a) TUBULAR SCAFFOLDINGS TUBULAR : 38 mm Ø Sch. 40 G.I. PIPE OR B.I. PIPE COUPLER: 6.25 kN CAPACITY AGAINST SLIP b) H – FRAME SCAFFOLDINGS UPRIGHTS: 38 mm Ø CAPACITY PER FRAME: 9.80 kN SIZE: Ht. = 1.70 m.; Width = 1.20 m.

33. TUBULAR SCAFFOLDING:

34. H – FRAME SCAFFOLDINGS:

35. 2.4.2 SAFE WORKING WORKING LOAD OF SCAFFOLD: SWL SWL = DL + 2 LL DL = Wt. OF PLANKS; Wt. OF LEDGERS, COUPLERS, TRANSOM, UPRIGHT, LADDER, BRACINGS, AND COUPLERS LL = Wt. OF WORKERS, TOOLS & MATERIALS 2.4.3 ESTIMATING FORMWORKS & SCAFFOLDINGS: 2.4.3.1 LUMBER FORMWORKS: QUICK ESTIMATES MATERIALS: a) 2 x 2 LUMBER RIBS FORM LUMBER: 110 – 140 bd.ft . per cu.m . of CONCRETE

36. b) COMMON WIRE NAILS 1 keg ASSORTED NAILS per 2,000 bd.ft . of FORM LUMBER 1 keg = 45 kg. Nails: 1” Nails for sheating @ 0.033 kg. per sq.m . 2 ½ “ Nails for Lumber Ribs @ 0.08 kg. per sq.m . c) FORM PLYWOOD OR PHENOLIC BOARD: 0.8 pcs. of 1.20 x 2.40 BOARD per cu.m . of CONCRETE

37. 2.4.3.2 estimate factors in computing lumber forms TABLE 2.6 BOARD FOOT LUMBER PER SHEET OF FORM Lateral Perimeter of Column “P”: P = 2(a + b) + 0.20 a = Shorter side of column in meters. b = Longer side of column in meters Lateral Perimeter of Beams “P”: P = 2(d) + b + 0.10 d = The depth of side forms in meters. b = The width of bottom form in meters SIZE OF THICKNESS OF PLYWOOD OR PHENOLIC LUMBER COLUMN BEAM (in.) 6 mm 12 mm 6 mm 12 mm 2 X 2 29.67 20.33 25.06 18.66 2 X 3 44.50 30.50 37.60 28.00

38. TABLE 2.7 QUANTITY OF METAL FORM FOR CIRCULAR COLUMNS NOTE: a) VERTICAL RIBS COULD BE LUMBER OR STEEL b) CIRCUMFERENTIAL AREA OF COLUMN: C = π D (Ht.) (No. of Columns); D = Column Diameter SIZE OF METAL No. SHEETS LENGTH OF VERT. RIBS IN METERS LENGTH OF CIRCUMFERENTIAL SHEETS PER M 2 SPACING IN CM. TIES IN METERS (M.) 15 CM. 20 CM. 0.9 X 2.40 0.462 25.00 18.00 9.52 1.20 X 2.40 0.347 25.00 18.00 9.52

39. 2.4.3.3 COMPUTING LUMBER FORMWORKS: COLUMNS: P = 2(a + b) + 0.20 Ex 1.0 Calculate the number of 2 x 2 lumber for ribs and the number of 12 mm thick plywood for use as forms for 8 pcs. 0.40 x 0.50 m. column section 4.00 m. high. Lateral Perimeter of Column “P”: P = 2(a + b) + 0.20 P = 2(0.40 + 0.50) + 0.20 = 2.00 m. Area = P ( Column Ht.) (No. of Cols.) = 2 (4) (8) = 64 sq.m . No. of Plywood = Area / Area of Plywood = 64 / 1.2(2.4) = 22.22 pcs. Say 23 pcs. No. pcs. 2 x 2: From Table 2.6 (12mm plywood - 20.33) No. bd. ft. = 20.33 (23) = 467.59 bd. ft. (Use: 2 x 2 x 8)

40. No. bd. ft. (2 x 2 x 8) = 2 (2)(8) / 12 = 2.67 bd.ft . No. pcs = 467.59 / 2.67 = 175.13 say 176 pcs. - 2 x 2 x 8 Nails: 1” Nails for sheating @ 0.033 kg. per sq.m . 2 ½ “ Nails for Lumber Ribs @ 0.08 kg. per sq.m . No. kg. Nails: 1” : No. kg. = 0.33 P = 0.033 (64) = 2.1 say 2.5 kg. 2 ½” : No. kg = 0.08 P = 0.08(64) = 5.12 say 5.5 kg. Ex 2.0 Calculate the number of 2 x 2 lumber for ribs and the number of 12 mm thick plywood for use as forms for 12 pcs. 0.30m. wide by 0.45 m. deep beam with a clear span of 5.00 m. Lateral Perimeter of Column “P”: P = 2(d) + b + 0.10 P = 2(0.45) + 0.30 + 0.10 = 1.30 m.

41. Area = P ( Beam Span) (No. of Beams) = 1.3(5)(12) = 78 sq.m . No. of Plywood = Area / Area of Plywood = 78 / 1.2(2.4) = 27.1 pcs. Say 28 pcs. No. pcs. 2 x 2: From Table 2.6 (12mm plywood - 20.33) No. bd. ft. = 20.33 (28) = 569.24 bd. ft. (Use: 2 x 2 x 12) No. bd. ft. (2 x 2 x 12) = 2 (2)12) / 12 = 4 bd.ft . No. pcs = 569.24 / 4 = 142.3 say 143 pcs. - 2 x 2 x 12 Nails: 1” Nails for sheating @ 0.033 kg. per sq.m . 2 ½ “ Nails for Lumber Ribs @ 0.08 kg. per sq.m . No. kg. Nails: 1” : No. kg. = 0.33 P = 0.033 (78) = 2.6 say 3 kg. 2 ½” : No. kg = 0.08 P = 0.08(78) = 6.24 say 6.5 kg.

42. 2.4.3.4 LUMBER SCAFFOLDINGS AND STAGINGS: LUMBER SCAFFOLDING - A TEMPORARY STRUCTURE OF WOODEN POLES AND PLANKS PROVIDING PLATFORM FOR WORKERS WHILE ERECTING OR REPAIRING A STRUCTURE. STAGING - A MORE SUBSTANTIAL FRAMEWORK PROGRESSIVELY BUILT-UP AS TALL STRUCTURES RISES UP. IT IS BUILT UP INNSTAGES ONE STOREY AT A TIME. DIFFERENT PARTS OF SCAFFOLDINGS: a) VERTICAL SUPPORT OR UPRIGHT (2 x 3 or 2 x 4) b) BASE OF VERTICAL SUPPORT OR MUD SILL c) HORIZONTAL MEMBER OR LEDGER (2 x 3 or 2 x 4)

43. d) HORIZONTAL AND DIAGONAL BRACES (2 x 2) e) BLOCK AND WEDGES – AS NEEDED f) NAILS (4” CWN) Horizontal Member Horizontal Bracing Vertical Member Column TYPICAL COLUMN SCAFFOLD (TOP VIEW)

44. TYPICAL ELEVATION OF COLUMN SCAFFOLDS Bracings Vertical Member Horizontal Member Column Mud Sill

45. 2.4.3.5 ESTIMATING MATERIALS FOR SCAFFOLDING AND STAGING: TABLE 2.8 QUANTITY OF LUMBER FOR SCAFFOLDING LUMBER COLUMN BEAM FLOORING SIZE Bd. Ft. / Meter Ht. Bd. Ft. / Meter Ht. Bd. Ft. per M 2 (in.) Vert. Hor. Brace Vert. Hor. 2 x 2 4.70 21.00 11.70 4.00 4.70 6.10 2 x 3 7.00 31.67 17.50 6.00 7.00 9.10 2 x 4 9.35 42.25 23.35 8.00 9.35 12.10

46. Ex 3.0 Calculate the materials for lumber scaffolding needed for 12 columns 4.00 m. in height and floor slabs. Four columns are spaced 5.00 m. apart along the E – W direction and three columns spaced 6.00 m. apart along the N – S direction. Use 2 x 3 for vertical and horizontal members and 2 x 2 for horizontal and diagonal bracings. SCAFFOLDINGS FOR COLUMNS: Total Length of Columns = 12 (4) = 48 m. Vertical Scaffolds : From Table 2.8 : For 2 x 3: 7 bd.ft . per m. ht. No. of bd.ft . = 48(7) = 336 bd.ft . Using 2 x 3 x 12 Lumber = 6 bd.ft . No. pcs. = 336 / 6 = 56 pcs. - 2 x 3 x 12

47. Horizontal Supports : From Table 2.8 : For 2 x 3: 31.67 bd.ft . per m. ht. No. of bd.ft . = 48(31.67) = 1,520.16 bd.ft . Using 2 x 3 x 12 Lumber = 6 bd.ft . No. pcs. = 1,520.16 / 6 = 253.6 say 254pcs. - 2 x 3 x 12 Diagonal Bracings: From Table 2.8 : For 2 x 2: 11.7 bd.ft . per m. ht. No. of bd.ft . = 48(11.7) = 561.6 bd.ft . Using 2 x 2 x 10 Lumber = 3.33 bd.ft . No. pcs. = 561.6 / 3.33 = 168.65 say 167pcs. - 2 x 3 x 12

48. SCAFFOLDINGS FOR THE BEAMS: Total Length of Beams = 5 (3)(3) + 6(2)(4) = 93 m. Vertical Supports : From Table 2.8 : For 2 x 3: 6 bd.ft . per m. ht. No. of bd.ft . = 93(6) = 558 bd.ft . Using 2 x 3 x 12 Lumber = 6 bd.ft . No. pcs. = 558 / 6 = 93 pcs. - 2 x 3 x 12 Horizontal Supports : From Table 2.8 : For 2 x 3: 7 bd.ft . per m. ht. No. of bd.ft . = 93(7) = 651 bd.ft . Using 2 x 3 x 12 Lumber = 6 bd.ft . No. pcs. = 651 / 6 = 108.5 say 109pcs. - 2 x 3 x 12

49. SCAFFOLDINGS FOR THE SLABS: 6 SLABS Area of Slabs = 5 (6)(6) = 180 sq.m . Vertical Supports : From Table 2.8 : For 2 x 3: 9.1 bd.ft . per sq. m. No. of bd.ft . = 180(9.1) = 1,638 bd.ft . Using 2 x 3 x 12 Lumber = 6 bd.ft . No. pcs. = 1,638 / 6 = 273 pcs. - 2 x 3 x 12 Common Wire Nails: 4” Nails 0.73 kg. Nails per Meter Length: No. kgs . = (48 + 93)(0.73) = 103 kgs . - 4” CWN

50. 2.4.3.6 LABOR ESTIMATE FOR FORMWORKS AND SCAFFOLDINGS 2.4.3.6.1 FORMWORKS FORMWORKS FABRICATION: 1.0 M-H per sq. m. FORMWORKS INSTALLATION: WALL ON GROUND: 2.00 M-H per sq. m. WALL ABOVE GROUND: 2.35 M-H per sq. m. BEAMS & COLUMNS: 2.35 M-H per sq. m. SUSPENDED SLAB: 0 to 18” Thick 1.67 M-H per sq. m. 10 to 36” up 3.33 M-H per sq. m.

51. FORMWORKS FOR ELEVATED & SHORED SLAB: FORMWORKS ONLY 1.67 M-H per sq. m. FORRMWORKS & SHORING 3.33 M-H per sq. m. WOOD WALL & PARTITION 0.50 M-H per sq. m. STRIPPING OF FORMS: WALL ON GROUND: 0.25 M-H per sq. m. WALL ABOVE GROUND: 1.29 M-H per sq. m. BEAMS: 1.03 M-H per sq. m. COLUMNS: 0.85 M-H per sq. m. SUSPENDED SLAB: 0 to 18” Thick 0.83 M-H per sq. m. 10 to 36” up 1.08 M-H per sq. m. ELEVATED AND SHORED SLAB: 3.50 M-H per sq. m. FLOOR SLAB AT GRADE: 2.80 M-H per sq. m.

52. TABLE 2.8 FORMWORKS FABRICATION & INSTALLATION WORK ITEM MANHOURS per SQ. M. Carpenter Laborer Total Continuous Wall - CHB 0.70 0.40 1.10 Pile Caps 1.50 0.65 2.15 Footing Tie Beams 0.75 0.40 1.15 Walls Up to 2.40 m. High 1.10 0.72 2.92 Walls 2.40 to 5.00 m. High 1.21 0.78 1.99 Walls 5.00 to 6.00 m. High 1.35 0.90 2.25 Columns 1.22 0.80 2.02 Beams & Girders 1.90 1.22 3.12 Elevated Slabs 1.15 1.16 2.31

53. TABLE 2.9 ERECTING LUMBER SCAFFOLDINGS LENGTH (M.) MANHOURS per SECTION 1 – 2 Section High More Than 2 Sections High Erect Dis-mantle Total Erect Dis-mantle Total 1 – 2 Sections 1.20 0.35 2.05 1.40 1.00 2.40 3 – 5 Sections 0.75 0.50 1.25 0.85 0.60 1.45 6 or More Sections 0.65 0.35 0.95 0.75 0.40 1.15

54. LABOR IN ERECTING METAL SCAFFOLDINGS: FOR EVERY 100 sq. m. of VERTICAL SURFACE: 3 Men for 2 Days Total Erection Hours - 55 Hours Dismantling of Scaffolds - 45% of Erection Hours Total Hours Erection & Dismantle - 80 Hours

55. 2.5 ESTIMATING CONCRETE WORKS 2.5.1 INTRODUCTION: MATERIAL REQUIREMENTS: CEMENT; SAND; GRAVEL; WATER; AND ANY ADDITIVES. LABOR REQUIREMENTS: MASONS; STEELMEN; COMMON LABORERS; EQUIPMENT OPERATORS; FOREMAN. EQUIPMENT AND TOOL REQUIREMENTS: ON-SITE MIXING: CONCRETE MIXER; CONCRETE VIBRATOR; PORTA LIFT; BUCKET LIFT; CONSTRUCTION PAILS; SPADES; WATER BARRELS / TANKS; PPE’S; BUGGYS.

56. READY MIXED: TRANSIT MIXER; CONCRETE PUMP (PUMPCRETE); VIBRATOR; PORTA LIFT; BUCKET LIFT; CONSTRUCTION PAILS; SPADES; PPE’S; BUGGY 2.5.2 CONCRETE WORKS SPECIFICATIONS: CLASS “AA” CONCRETE MIX: 1 : 1.5 : 3 PROPORTION 1 BAG CEMENT; 1.5 BAGS SAND; 3 BAGS GRAVEL; 5 to 7 GALS. WATER. CLASS “AA” IS USED IN SPECIAL CONCRETING WORKS REQUIRING HIGH STRENGTH CONCRETE.

57. CLASS “A” CONCRETE MIX: 1 : 2 : 4 PROPORTION 1 BAG CEMENT; 2 BAGS SAND; 4 BAGS GRAVEL; 5 to 7 GALS. WATER CLASS “A” MIX IS GENERALLY USED IN CONCRETING OF BEAMS AND GIRDERS, SLABS, COLUMNS, FOOTINGS; STAIRWAYS; AND REINFORCED CONCRETE WALLS AND OTHER STRUCTURAL COMPONENTS SUBJECTED TO BENDING STRESS.

58. CLASS “B” CONCRETE MIX: 1 : 2.5 : 5 PROPORTION 1 BAG CEMENT; 2.5 BAGS SAND; 5 BAGS GRAVEL; 5 to 7 GALS. WATER CLASS “B” MIX IS GENERALLY USED IN NON-STRUCTURAL CONCRETING WORKS. CLASS “C” CONCRETE MIX: 1 : 3 : 6 PROPORTION 1 BAG CEMENT; 3 BAGS SAND; 6 BAGS GRAVEL; 5 to 7 GALS. WATER CLASS “C” MIX IS GENERALLY USED IN MINOR CONCRETING WORKS.

59. 2.5.3 CONCRETE MATERIAL SPECIFICATIONS: CEMENT: PORTLAND CEMENT; 40 KG. / BAG SAND OR FINE AGGREGATE: CLEAN NATURAL SAND OR CRUSHED STONE PASSING ON A 5 MM SIEVE. GRAVEL OR COARSE AGGREGATE: CLEAN NATURAL GRAVEL OR CRUSHED STONE WITH PARTICLES RETAINED ON A 5 mm SIEVE. USUAL AGGREGATE SIZE IS 20 mm

60. WATER: CLEAN AND FREE FROM OIL, SALT, SILT, AND OTHER HARMFUL IMPURITIES. PRINCIPLES OF CONCRETE MIX - A CONCRETE MIX THAT WILL MEET THE FOLLOWING REQUIREMENTS: WORKABILITY - FRESH CONCRETE COULD FREELY FLOW AROUND THE REBARS. STRENGTH - STRONG ENOUGH TO CARRY THE DESIGN LOAD. DURABILITY - HARDENED CONCRETE EXPECTED TO WITHSTAND ADVERSE CONDITIONS. ECONOMY - CONCRETE SHOULD BE ECONOMICALLY PRODUCED

61. CONCRETE MIX CLASSIFIED: DESIGNED MIXTURE - THE CONTRACTOR IS RESPONSIBLE IN ESTABLISHING THE MIXING PROPORTION REQUIRED TO ACHIEVE THE REQUIRED STRENGTH. PRESCRIBED MIXTURE - THE DESIGNING ENGINEER SPECIFY THE MIXTURE PROPORTION. SLAB WITH STEEL DECK: EFFECTIVE WIDTH OF STEEL DECK: 250 to 990 mm LENGTH: CUT ACCORDING TO SPECIFICATIONS

62. 2.5.4 ESTIMATE FACTORS IN CONCRETE ESTIMATE TABLE 2.10 - ESTIMATE FACTORS IN CONCRETE WORKS: CLASS PROPORTION MATERIALS CEMENT (BAGS) SAND (CU. M.) GRAVEL (CU. M.) WATER (GALS.) “AA” 1 : 2 : 3 12.0 0.50 1.0 5 – 7 gals. “A” 1 : 2 : 4 9.0 0.50 1.0 5 – 7 gals. “B” 1 : 2.5 : 5 7.5 0.50 1.0 5 – 7 gals. “C” 1 : 3 : 6 6.0 0.50 1.0 5 – 7 gals.

63. 2.5.4.1 ESTIMATING CONCRETE MATERIALS EX 1.0. FIND THE QUANTITY OF CEMENT, SAND, GRAVEL, AND WATER FOR A 20 M. X 30 M. X 0.125 M. THICK SLAB USING CLASS “A” CONCRETE. ASSUME 6 GALS. WATER PER BAG OF CEMENT. VOLUME = 20(30)(0.125) = 75 CU. M. CEMENT = 75 (9) = 675 BAGS SAND = 75 (0.5) = 37.5 CU. M. GRAVEL = 75 (1) = 75 CU. M. WATER = 675 (6) = 4,050 GALS. [0.02 cu. m.] NOTE: 1 GAL. = 0.13378 cu.ft . x [28.327 x 10 -6 ] = cu. m.