Metal Building Foundations Package – Soils Report Foundation Design When you a purchase a pre engineered metal building most often your steel building supplier does not do the foundation design However you are required by the City or County to get a soils report and foundation design plans Foundation Engineering Consultants Inc has a package for a 11 04 2017 nbsp 0183 32 The projects consisted of the design of some metal building foundations In each instance the columns rested on a knee wall that was approx 3 0 high with a required frost depth of 4 0 In each instance I have approximately 15 0 kips placed at the top of the wall I designed the foundations and sent them off to the client only to get irate phone calls back about the Figure 2 Common Foundations Used in Metal Building Systems a Tie rod b Hairpins with slab ties c Moment resisting foundation d Slab with haunch Figure 2 continued Common Foundations Used in Metal Building Systems e Trench footing f Mat g Deep foundations 10 08 2004 nbsp 0183 32 A quot typical quot PRELIMINARY foundation design for a metal building in the Midwest subject to snow loads with a frost penitration of about 4 that would allow a general contractor to price the foundation system based on allowable soil bearing of 3 000 psf would be Perimeter frost wall footings 24 quot wide x 10 quot deep w 3 5 cont and 5Depth of foundation below ground 2 5 m Type of soil Type II Medium as per IS 1893 Steel HYSD reinforcement of grade Fe 415 confirming to IS 1786 is used throughout 1 2 Geometry of the Building The general layout of the building is shown in Figure 1 At ground level the floor beams FB are not provided since the floor directly rests on ground earth filling and 1 4 8 c c

Decay damage and repairs of foundation are not very common events of buildings Actually if foundations like grillage and deep foundations like pile raft under reamed pile etc are damaged the entire building gets affected and repairs of these foundations are rarely possible Hence maintenance of these foundations for up keeping which cannot be generalised is not a Steel grillage foundation b Timber grillage foundation Timber grillage foundations may be used below the walls From the nature of construction it is evident that steel grillage foundation if constructed properly and load distributed on the soil below is within safe bearing capacity of the soil the foundation need very little maintenance In this chapter we look into the differences between foundations for metal building systems and those for conventional construction and examine some common solutions We will not deal with the basics of foundation design a subject that should be familiar to any practicing structural engineer and hopefully to most architects Similarly we will not delve into the complex topic Example 1 Pad Footing Axial Load Cracking h 450 mm 200 mm Steel stress 𝑓 192 0 3 1 35 192 1 5 186 186 1 15 600 0 3 215 400 1 35 215 600 1 5 215 400 2611 2715 500 1 15 213 N mm2 For design crack width 0 3 mm Maximum allowable bar spacing 200 mm Actual bar spacing 3000−235−12 23 127mm 200 mm Cracking OKSTRUCTURE magazine Foundations for Metal Building Systems Top www structuremag org Metal building systems MBS also known as pre engineered metal buildings are proprietary structures designed and manufactured by their suppliers Metal buildings are extremely popular and they account for a substantial percentage of low rise nonresidential buildings in the

Chapter 12 FOUNDATION DESIGN FOR METAL BUILDING SYSTEMS 12 1 INTRODUCTION Foundations contrary to the dreams of building owners do not come prepackaged with metal building systems The concept of single source responsibility for pre engineered buildings is qualified by the fact that the foundations are usually designed by 13 02 1971 nbsp 0183 32 Footings Example 1 Design of a square spread footing of a seven story building Design and detail a typical square spread footing of a six bay by five bay seven story building founded on stiff soil supporting a 24 in square column The building has a 10 ft high basement The bottom of the footing is 13 ft below finished grade The building is assigned to Seismic Designed for quality fast and economical installation and low maintenance All buildings meet applicable codes and incorporate state of the art design and manufacturing technology Metal building components including roof and wall panels trims bi fold doors sliding doors stack doors C s Z s and eave struts are also available Instructional Materials Complementing FEMA 451 Design Examples Foundation Design 14 38 Tie Between Pile Caps 2 6 top bars 3 6 bottom bars 4 ties at 7 quot o c 2 quot clear at sides 3 quot clear at top and bottom Designed for axial force Pile cap axial load times S DS 10 Often times use grade beams or thickened slabs one gradeDesign of Pad Footing Cracking amp Detailing Requirements All reinforcements should extend the full length of the footing If gt 1 5 3 at least two thirds of the reinforcement parallel to L y should be concentrated in a band width 3 centred at column where L x amp L y and c x amp c y are the footing and column dimension in x and y directions Reinforcements should be anchored each