FORM MATERIALS We finished Chapt. 1 & 2 and we are reviewing Chapt. 3 & 4!!! Chapter One- Introduction to Forming Chapter Two- General Objectives in Formwork Building Chapter Three-Overall Planning for Formwork Chapter Four-Materials, Accessories, Proprietary Products Book Overview

What are the objectives of any form design? The form design must provide, SAFETY THE BEST QUALITY ECONOMICS (PLANNING & COST)

What types of forms are used in formwork? 1. Prefab Forms 2. Pans and Domes for concrete joist 3.Void and Duct Forms 4.Column Forms 5. Stay-in-place forms What types of shoring is used in formwork? 1.Shoring Scaffolding 2.Vertical Shores 3.Scaffold-Type Shoring 4.Horizontal Shoring

What materials and accessories are used in formwork? 1. Lumber 2. Steel 3.Aluminum 4. Glass-Fiber-Reinforced Plastics(4-16) 5.Fabric Forms(4-18) 6. Form Lining Materials(4-20) 7.Fasteners (4-25 to 4-33) 8. Ties(4-34) 9.Anchors(4-36) 10 Hangers(4-37) 11. Jacks(4-37) 12. Spreaders & Spacers(for rebars) Steel Strapping & Column Clamps (4-39&40) 14. Prefab Forms (4-41) video 15. Pans and Domes (4-45)

1. Lumber (overview) Choice of lumber is affected by the availability and cost Lumber is required to be straight, structurally sound, and partially seasoned (19-25%) Note: Do not use old lumber with new. If lumber is too dry it will swell under moist conditons, and if too moist it will shrink in dry conditions. Commonly used lumber is the DF-L, DF-S, Spruce-Pine Fir, and Hem-Fir Dressed lumber is used for formwork, and the rough sawn boards are used in bracing and shoring. (formwork used here means the members that are used to shape the concrete)

1. cont. Lumber (overview) Dressed lumber is surfaced lumber (i.e. S1SE,S1S2E,S4S,etc) Refer to P. 4-4 for wood properties also P.4-6 for wood stresses, note there is no F t (tension parallel to the grain) Note adjustment factors as noted on P. 4-6 & 4-7. No size adjustment is required for construction and standard grade lumber Engineered Wood Products are becoming more common due to dwindling supplies of sawn lumber and in many cases can give us better strength characteristics. (i.e. glulam, LVL, etc.)

1. cont. Lumber(Plywood/Sheathing) Plywood is common in most systems as sheathing Sheathing is used in direct contact with concrete. It is primarily : plywood, steel, aluminum, etc. It does not include liner panels or other surfacing directly contacting concrete Why do we need to protect plywood? Concrete has water Concrete is an alkaline Concrete has abrasive constituents Concrete is heavy & a fluid

How do we protect plywood? 1. cont. Lumber(Plywood/Sheathing) We bond interior with water-resistant glue and exterior with water-proof glue exterior plywood is required for reuse What is overlaid plywood? Overlaid plywood is exterior plywood with additional resin-impregnated fiber faces permanently fused under heat and pressure It is either High Density Overlaid (HDO) or Medium Density Overlaid (MDO) Overlays provide high strength, light wt., dimensional stability, rock resistance

What is overlaid plywood? High Density Overlaid (HDO) P Overlays provide high strength, light wt., dimensional stability, rock resistance, hard and smooth Resin Overlay- add ability to Withstand severe exposure w/o further finishing Resists abrasion Prevent water penetration Prevent deterioration from chemicals &solvents Overlay thickness w/60#per 1000sf of panel surface Ply Bonding - 100% water proof glue Construction- Inner plies: C or C plugged and face is B or better Maximum reuse (200 pours)

What is overlaid plywood? (cont) Medium Density Overlaid (MDO) P Sanded two sides, oiled at will Needs good quality edge sealer before 1st pour (10 to 20 reuses) Not recommended for forms but can be used. Recommended use of a release agent Other overlays glass-fiber-reinforced plastic formica epoxy resin Non Overlaid Plywood Classification for veneer is A-D Classification for Panel Strength is Group 1 to 5(i.e DF-L is Strongest and in group#1)

2.& 3. Steel/Aluminum Pretty much used the same way as wood but allows for greater spans or heavier loads (i.e. channels,angles, I-beams, etc.) Aluminum is lighter weight and can produce forming units larger than other materials can manage.(i.e can be 50% wider than plywood, and have the same weight) For section 4-15 on the slide see video and follow textbook.

*4. Glass-Fiber-Reinforced Plastics(fig.4-53)

*5.Fabric Forms(fig. 4-15)

*6. Form Lining Materials(fig 4-17)

7.Fasteners (4-25 to 4-33)

*8. Ties(4-34)

9.Anchors(4-36)

10 Hangers(4-37)

*11. Jacks(fig 4-35)

*12. Spreaders & Spacers(for rebars) 4-38

13. Steel Strapping & Column Clamps (4-39&40)

14. Prefab Forms (4-41)

15. Pans and Domes (4-45)