scaffolding Standardsvertical members of frame work embedded into

scaffolding

• Standards-vertical members of frame work embedded into ground • Ledgers-horizontal members parallel to wall • Putlogs-transverse pieces placed on ledgers which are supported on wall • Transoms-putlogs with both ends supported on ledgers • Braces-diagonal pieces • Bridle-brige an opening in a wall it supports one end in putlog • Guard rail-rail provided with ledger • Raker- inclined support

SINGLE SCAFOLDING

Single scaffolding • Widely used in brick work • Single row of standards at a distance of 1. 2 m • Putlogs are placed at horizontal distance of 1. 2 to 1. 8 m

• Stronger than single scaffolding • Two rows of standards are provided • Distance between face of wall and first row of standards is 200 mm to 300 mm

Cantilever or needle scaffolding • May be single or double scaffolding • Needle supported on floor level

Suspended scaffoldings • Used for maintainance works • Working platform suspended from roof by ropes, wires or chains

Trestle scaffolding • Working platform supported by ladders, tripods mounted on wheels • Height of this type of scaffolding is 5 m fro supporting surface.

TRESSLE SCAFOLDING

Steel scaffolding • Steel tubes effectively used for scaffolding work • Can be used to any height • High intial cost • Skilled labour required

Patented scaffolding • Made of steel • Use of working platform supported by bracket

PATENDED SCAFOLDING

SHORING

shoring • They are temporary structures • Structures become unsafe due to unsettlement of foundations or removal of adjacent building • Shoring is required to prevent movements.

Circumstances when shoring is required • Adjascent structures is diamantled • Cracks due to unequal settlement of foundation • Large openings in walls • Poor workmanship

Types of shoring • Raking or inclined shores • Flying or horizontal shores • Dead or vertical shores

Raking shores • Consist of wall plate , needles, cleats, rakers, bracings, sole plate • Rakers prevent outward movement of wall • Large factor of safety is used for designed of inclined shores • Rakers inclined at 45ᵒ • Sole plate at ground

Flying or horizontal shores

Flying or horizontal shores • Horizontal support to parallel walls • Consist of wall plate , needles, cleats, struts etc • Suitable for max distance of about 9 m

Dead or vertical shores

Dead or vertical shores • Needles are supported by vertical members called shores. • Used under following circumstances - Lower part of wall is defective - -foundations are deepened - -lower part is to be rebuilt

UNDERPINNING

underpinning • Placing of new foundation above existing foundation

Circumstances used for underpinning • Building with deep foundations constructed to near building • Settlement of existing foundation • Basement is to be provided to existing building • Existing foundations to be deepened