RECO2006 Construction IV
Shoring
Edward CY YIU Department of Real Estate and Construction January 2007
Learning Objectives • What What is shor shorin ing g • Why sh shoring ing • Type Types so off s sho hori ring ng
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What is shoring? • Shoring (from "shore," a prop) is an operation connected with building building.. It is often necessary before actual building is begun to support adjoining premises while the work of excavating for underground apartments is being carried out. • The art of of shoring shoring comprises comprises the temp temporar orary y support of buildings, and may become necessary because of the failure or settlement of some portion of the structure or for the purpose of upholding the upper portion while alterations are being made in the lower. http://en.wikipedia.org/wiki/Shoring Propping = Bracing = Retaining Wall = Shoring?
Shoring Materials • There There are are several several differen differentt forms forms of shori shoring, ng, each each adapted to suit peculiar circumstances. • Much of the the shoring shoring for ordin ordinary ary cases cases is done done with with heavy, roughly sawn timbers strongly braced together, but for especially heavy work steel members may be introduced and prove of great value. • There There is the the troub trouble le in conne connectio ction n with with their their use, use, however, that connections between steel members are not made with the same facility as between pieces of timber. http://en.wikipedia.org/wiki/Shoring
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Types of Shoring • The The most most gen genera erall shori shoring ng is is the the raking shore. shore . – It consists consists of one or more more timbers timbers sloping sloping from the face face of the structure to be supported and bedded upon the ground. – As the ground ground is usually of a more or or less yielding yielding nature, nature, a stout timber plate termed a sole-piece sole-piece,, of sufficient area to withstand being driven into the soil, is placed to receive the base of the raking timber or timbers. – A wall-plate wall-plate,, with the object of increasing the area of support, is fixed to the face of the wall by means of hooks driven into the wall. – Where space space is available, available, an an angle of 60°is 60°is the best to to adopt for for the main shore, the auxiliary members ranging in their slope from 45°to 75°. – In many cases, cases, especial especially ly in towns, towns, the angle angle of slope is governed by outside influences such as the width of the footway.
http://en.wikipedia.org/wiki/Shoring
Types of Shoring (Cont’d) •
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Flying Shores In some situations, the close proximity of existing buildings, or the need to maintain access, may prevent the use of raking shores. In these situations, a flying shore may be effective. This This relie relies s on tran transm smit itti ting ng load loads s to the adjacent structures, for which obviously the owner's permission will be necessary. The The exist existing ing buil buildin ding g to be u use sed d for support should also be carefully inspected for its adequacy to carry additional loads.
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Types of Shoring (Cont’d) •
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Deed or Needle Shoring Dead or needle shoring, often more simply referred to as propping, is used for supporting existing walls, floors and roofing whilst works are carried out to form openings or remove walls at lower level. Stee Steell or timb timber er upr uprig ight hts s are are provided to support loads from a structure, normally in association with wedges or head and sole plates to distribute stresses over larger areas.
Type of Shoring (Cont’d) • She hee et Pili Pilin ng – For For a contin continuo uous us support of soil against collapse
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Examples of Sheet Piling
Sheet piling works at Fanling Fanling WSD Reserved Area for the construction of noise barrier foundation http://www.hyd.gov.hk/contractwebsites/fhnb/HY20 http://www.hyd.gov.hk/contractwebsites/fhnb/HY200320_FILES/PHOTO0501.HTM 0320_FILES/PHOTO0501.HTM
Type of Shoring (Cont’d) • Diap Diaphr hrag agm m Wall Wall • Cofferdam • Are Are th thes ese e shor shorin ing? g?
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Example of Propping - Source: http://www.sciglobal.com/falsework/20KPostShore.html http://www.sciglobal.com/falsework/20KPostShore.html
Source: http://www.sciglobal.com/falsework/20KPostShore.html http://www.sciglobal.com/falsework/20KPostShore.html
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Hyd Hyd Shori Shoring ng Guide Guidelin lines es
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Diaph Diaphrag ragm m Wall Wall – shorin shoring? g? • Diaphrag Diaphragm m wall wall can be be made made of reinfo reinforced rced concrete concrete to provide structural load-bearing elements for temporary or permanent retaining walls or both. • Cofferd Cofferdam am is a tempor temporary ary struc structure ture built built to to exclude exclude earth earth and water from construction area and thus permit the work inside the cofferdam to be carried out in the dry. • Retai etaini ning ng wall all is is … • Ref Refer er to to course course material materials s on civil civil works works
Cofferdam in IFC2
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References • PNAP PNAP 14 142, 2, 16 166 6 – Re Reta tain inin ing g Wal Walls ls • Building Building (Construct (Construction) ion) Regu Regulatio lations, ns, (Cap. (Cap. 123), Laws of Hong Kong • HD (2003 (2003)) Guide Guide to Tren Trench ch Excav Excavati ation on (Shoring Support and Drainage Measures), Highways Department, H
The End For enquiries, please send email to Edward CY YIU Department of Real Estate and Construction The University of Hong Kong
[email protected]
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