British Columbia Carpenter Apprenticeship Program

Transcription

1 British Columbia Carpenter Apprenticeship Program Level 2 Line B Competency B-3 Use Manufacturer s and Supplier s Documentation

2 Ordering Crown Publications, Queen s Printer PO Box 9452 Stn Prov Govt 563 Superior St. 2nd Flr Victoria, B.C. V8W 9V7 Phone: Fax: crownpub@gov.bc.ca Web: Copyright 2012 Industry Training Authority This publication may not be reproduced in any form without permission by the Industry Training Authority. Contact Director, Crown Publications, Queen s Printer at

3 SAFETY ADVISORY Please note that it is always the responsibility of any person using these materials to inform him/herself about the Occupational Health and Safety Regulation pertaining to his/her work. The references to WorkSafeBC safety regulations contained within these materials do not / may not reflect the most recent Occupational Health and Safety Regulation (the current Standards and Regulation in BC can be obtained on the following website:

4 Competency B-3 Use Manufacturer s and Supplier s Documentation Contents Objectives...2 Learning Task 1: Interpret Manufacturer s or Engineer s Specifications for Suspended Slab Forming...3 Learning Task 1: Self-Test BC CARPENTER APPRENTICESHIP PROGRAM LEVEL 2 1

5 Competency B-3 Use Manufacturer s and Supplier s Documentation The manufacturers and suppliers of building components and forming systems, in coordination with professional engineers, produce shop drawings for the assembly and installation of those components. This competency provides an example of the use of manufacturer s documentation for suspended slab forming. Carpenters should be able to understand manufacturer s and supplier s documentation. Objectives When you have completed the Learning Tasks in this Competency, you will be able to: use manufacturer s documentation use supplier s documentation describe size and spacing of components describe releasing, lowering, moving and flying describe infill panels and backer rods, deck covers and sleeve voids 2 BC CARPENTER APPRENTICESHIP PROGRAM LEVEL 2

6 Competency B-3 Learning Task 1 Learning Task 1 Interpret Manufacturer s or Engineer s Specifications for Suspended Slab Forming The manufacturers of forming systems, in coordination with professional engineers, produce shop drawings for the assembly, installation and moving of suspended slab forming systems. Most low-rise buildings have suspended slabs formed using scaffolding, shore posts, stringers, joists and formply. Once a building goes over four stories of typical floors, it becomes economical to use fly forms. Most tall buildings use cranes for a more efficient slab forming method. The cranes lift specialized forms for reuse from one floor level to the next. This type of forming system is known as slab tables, and is sometimes referred to as flytables or fly forms. A slab table consists of leveling feet, trusses, joists and formply. It may also include columns and shores. For a 50 storey building, a slab table may be used 50 times. Some storeys may be unique, requiring modification of the slab tables for that floor. Slab table trusses arrive at the job site as pieces that require assembly. Once the trusses have been assembled, the slab tables can be built. All of this must be done as per the manufacturer s and engineer s specifications. WorkSafeBC OHS Requirements Sections and of the OHS regulations stipulate what must be included in the drawings for slab tables. For each type of table, there must be a plan view, longitudinal view and cross section. The weight, centre of gravity and position of pickup points are to be shown. A step-by-step procedure for all phases of each cycle of assembly, flying, use, dismantling and reuse of each slab table must be detailed in the drawings, including procedures for non-typical floors. Understanding Terminology Many specialized types of construction have unique terms. In some cases, familiar terms might be used to mean something new. For example, suspended slab forming uses the term stringer to indicate a beam used for supporting formwork. BC CARPENTER APPRENTICESHIP PROGRAM LEVEL 2 3

7 Learning Task 1 Competency B-3 Terms like shores, A-frames, cords and falsework may be confusing to a carpenter the first time they read slab table plans. All plans will have the name and phone number of the person to contact with any questions. Never guess when in doubt. Interpreting the Plans and Specifications The graphics shown in this learning task are portions from several pages of a set of fly form drawings provided by National Forming Systems. The drawings are for Tower B of the Concord Pacific Building located between two bridges in downtown Vancouver. The project has four levels of parking under a 150,000 sq. ft. Costco warehouse. There are four residential towers above the warehouse ranging in height from 26 to 32 storeys. The towers are built of concrete frame construction using slab tables for the slab forming. The slab tables are to be relocated using a tower crane and electric winch. Assembly of Slab Tables Each slab table is made up using two or more trusses. Figure 1 shows the plan view for Table 3. Figure 1. Plan view for table 3 4 BC CARPENTER APPRENTICESHIP PROGRAM LEVEL 2

8 Competency B-3 Learning Task 1 The table has three trusses; T5, T6, and T7, and four pickup points. The lengths of the bottom and top cords are shown. Joists are 4 16 o.c. The table has shores that need to be placed after the table has been landed and before the rigging is released (see Figure 6 Note A). On top of two shores is a short aluminum stringer indicated by a straight line with short crosses on each end. The length of the truss cords are shown as a number inside a rectangular box. For example, Truss T-6 has a 25 foot long single piece bottom cord and a top cord made from two 15 foot long pieces. We can also see from Figure 1 that the space between Tables 2 and 3 is 1 1. The width of the space will determine how the filler panel will be formed and supported. The bold arrow that caps the table number box shows the direction for flying the form out from the building. Figure 2. Typical cross sections BC CARPENTER APPRENTICESHIP PROGRAM LEVEL 2 5

9 Learning Task 1 Competency B-3 As most cross sections are similar, an easy way to reduce the number of drawings is to create a drawing that acts as a schedule. Figure 2 shows grey shaded areas to represent the concrete slabs. The lower slab is reshored (not shown) and supporting the slab table, and the upper slab has yet to be placed. Looking at the notations for Table 3, the 4 6 joists cantilever past the centre of the upper cord by 1 ½ and the on centre for the trusses is 6 1. Floor to floor height, leg height, slab thickness and one other vertical measurement is shown. Figure 3. Side elevation for table 3 A side elevation drawing is required for each truss. It shows the spacing of the A-Frames, location of legs, location of pick up points and direction of flight out from the building. In addition to the top and bottom cord and A-Frames, this truss also includes a column. A column may be required for extra strength or because of a non-typical floor. Typically, most slab tables have a working deck for walking on and setting down tools and materials while placing concrete. This is shown in Figure 3 with a guardrail and in Figure 1 by a dark line. 6 BC CARPENTER APPRENTICESHIP PROGRAM LEVEL 2

10 Competency B-3 Learning Task 1 Figure 4. Attachment of joists Figure 4 shows the pattern for using clips to attach the wooden joists to the aluminum top cords of the trusses. The note states that for the end joists, clips are to be installed on both sides of each cord. With the information shown in Figures 1 to 4, carpenters assemble the trusses and then use them to build the tables. These tables will be leapfrogged from floor to floor and in this case, used about thirty times. BC CARPENTER APPRENTICESHIP PROGRAM LEVEL 2 7

11 Learning Task 1 Competency B-3 Infill Between Tables Infill is typically required between adjacent slab tables, and between tables and shearwalls, columns and elevator shafts. Figure 5. Filler detail drawings Infill formply support is based on the span, load and other factors. Unless detailed in the plan view (Figure 1), a typical detail is used. As the space between Tables 2 and 3 is less than 18, the top detail of Figure 5 will be used. This calls for a 3 lap over the joist framing of the two tables, and no additional shoring is required. 8 BC CARPENTER APPRENTICESHIP PROGRAM LEVEL 2

12 Competency B-3 Learning Task 1 and Legends Figure 6. are added to clarify certain requirements. They also reduce the amount of writing on drawings, making the drawings easier to read. Note A in Figure 6, for example, states that if a shore is shown on a drawing with a cloud around it, then that shore must be installed before the crane is unhooked. Legends serve to indicate what different symbols stand for. In Figure 7, the shaded in triangle indicates a pick up point. BC CARPENTER APPRENTICESHIP PROGRAM LEVEL 2 9

13 Learning Task 1 Competency B-3 Figure 7. Symbols legend Shoring Suspended slab forming requires vertical support which is known as shoring. Shoring is also referred to as falsework. There are many common types of shores, five of which are shown in the shoring legend below. Figure 8. Shoring legend 10 BC CARPENTER APPRENTICESHIP PROGRAM LEVEL 2

14 Competency B-3 Learning Task 1 As forms are stripped, the concrete will need temporary support for two possible reasons. The first is that the concrete might not have reached enough strength yet to support itself. The second reason is that during construction, there are often temporary loads placed on the slabs that exceed the design strength. Support that is provided for either of these reasons is known as reshoring. Reshoring often extends down three, four or more floor levels to share the load. Slab table plans will have a reshore plan view showing the type and location of reshores. Slab tables will shown along with the reshores in a cross sectional view (Figures 9 and 10). Figure 9. Reshore plan view for table 3 area BC CARPENTER APPRENTICESHIP PROGRAM LEVEL 2 11

15 Learning Task 1 Competency B-3 Figure 10. Reshoring cross section (showing one floor level of forming and three floor levels of reshoring) 12 BC CARPENTER APPRENTICESHIP PROGRAM LEVEL 2

16 Competency B-3 Learning Task 1 Weights, Reach and Flying Figure 11. Table weights and crane reach Figure 12. Flying procedures BC CARPENTER APPRENTICESHIP PROGRAM LEVEL 2 13

17 Learning Task 1 Competency B-3 WorkSafeBC requires that the information needed for flying forms be included in the manufacturers specifications. This includes table weight, crane reach and flying procedure. Typically, weight and reach is provided in a table format as shown in Figure 11. Flying procedures are shown step by step in Figure 12. Table handling will be covered in the G-line modules on slab tables. Now complete Learning Task 1 Self-Test. 14 BC CARPENTER APPRENTICESHIP PROGRAM LEVEL 2

18 Competency B-3 Learning Task 1 Learning Task 1 Self-Test 1. In Figure 1, the three items shown inside cloud drawings are: a. shoring revisions b. #2 shores c. #3 shores d. Mega shores 2. The pick up points in both directions for Tables 3 are how far apart? a and 6 1 b. 6 1 and 15 0 c and 15 0 d and only shown in one direction 3. How many A-Frames are shown in Truss T5? a. 3 b. 4 c. 8 d Which truss(es) in Table 3 includes a column? a. Truss T5 b. Truss T6 c. Trusses T5 and T6 d. Trusses T5, T6 and T7 5. The cantilever of the top cord past the A-Frames for Truss T5 is: a. 1 3 b. 1 6 c. 1 9 d The three trusses for Table 3 have a total of how many legs? a. 10 b. 11 c. 12 d. 14 BC CARPENTER APPRENTICESHIP PROGRAM LEVEL 2 15

19 Learning Task 1 Competency B-3 7. If the plans call for 32 MPa concrete for the slabs and that strength has been reached, how many floor levels of reshores are required? a. 2 b. 3 c. 4 d. reshoring is not required 8. What is the weight and crane reach for Table 3? a. 8,750 lbs and b. 7,350 lbs and c. 6,850 lbs and 28.5 d. 6,850 lbs and The tag line for flying the forms is to be what diameter and rope type? a. nylon b. nylon c. polypropylene d. polypropylene 16 BC CARPENTER APPRENTICESHIP PROGRAM LEVEL 2