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THE STRUCTURAL SHOP LTD CONSULTING ENGINEERS

9601 RIVER STREETSCHILLER PARK, ILLINOIS 60176(847) 349 1099 PHONE(847) 349 1098 FAXmail@thestructuralshop.com

August 2, 2012

Theatrical Media Services, Inc.7510 Burlington StreetOmaha, Nebraska 68127

Re: 44’x38’ 6 Post Stage Roof with Fly Bays – (2 - 91” Fly Bays)

TSS Job #: 12165

Mr. Tim Kohlmeyer:

We have analyzed the referenced structure in order to determine its gravity andlateral load carrying capacity. Enclosed please find a copy of the trussinformation, tower and sleeve block information, overall assembly information,guy wire tie down forces, load capacity schedule, engineering documentation, andoperations management plan.

Complete sets of engineering calculations for your records or use are availableupon request electronically. If there are any additional load schemes needed, wecan model them on our structural analysis program to determine the structuraladequacy of the referenced structure.

The maximum allowable service loads for the roof top and fly bays is provided inthe attached load table. Loads applied to the trusses must be applied at trusspanel points. The maximum uniform load, point load at the center, point load atthird points and point load at quarter points is shown in the schedules.

The stage roof top capacity was determined by using the Entertainment Servicesand Technology Association (ESTA) version of the American National StandardsInstitute (ANSI) document E1.21 – 2006, ‘Entertainment Technology TemporaryGround-Supported Overhead Structures Used to Cover the Stage Areas andSupport Equipment in the Production of Outdoor Entertainment Events’.Additional standards and material codes are referenced by the E1.21 document.See the engineering documentation for a full list of additional standards andmaterial codes.

The stage roof has been designed for a 40 mph, 3 second gust as described bythe referenced standards. When winds are reasonably expected to exceed a 40mph, 3 second gust, much of the equipment and accessories being supported bythe roof top must be removed or lowered to the ground. See operationsmanagement plan for specific requirements.

This roof top has been designed to be used in an open exterior space. When usedadjacent to another structure or within a partly enclosed building, it must beunderstood that the surrounding structure cannot be considered as a shield forthe wind forces.

THE STRUCTURAL SHOP LTD CONSULTING ENGINEERS

9601 RIVER STREETSCHILLER PARK, ILLINOIS 60176(847) 349 1099 PHONE(847) 349 1098 FAXmail@thestructuralshop.com

Temporary Stage Roof Design

In accordance with:

Entertainment Services and Technology Association (ESTA)American National Standard E1.21-2006

Entertainment TechnologyTemporary Ground-Supported Overhead

Structures Used to Cover the Stage AreasOf Outdoor Entertainment Events

Relevant Standards used in the design:

ASCE 7, “Minimum Design Loads for Buildings and Other Structures”

ASCE 37, “Design Loads on Structures During Construction”, Section 6 only.

ASCE19, “Structural Applications of Steel Cables for Buildings”

The Aluminum Association, “Specifications & Guidelines for Aluminum Structures”

American Institute of Steel Construction, “Code of Standard Practice for SteelBuildings and Bridges”

American Institute of Steel Construction, “Manual of Steel Construction – AllowableStress Design”

Stage Roof – 6 Post – with Fly Bays

Wind Design per ASCE 7:

Stage Roof Structure is considered an ‘Open Structure’, according to Section6.2 Definitions

Determination of wind forces is per Section 6.5 Method 2 – AnalyticalProcedure

6.5.3 Design Procedure 1. V = 90 mph (basic wind speed) Kd = 0.85 (wind directionality factor)

2. I = 1.0 (importance factor)

3. Kz = 1.0 (velocity pressure exposure coefficient) Kh = 1.0 (velocity pressure exposure coefficient)

4. Kzt = 1.0 (topographic factor)

5. G = 0.85 (gust effect factor)

6. Open (enclosure classification)

7. GCpi = 0.0 (internal pressure coefficient)

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8. External Pressure Coefficients – Do not apply to the roof becauseit is an ‘Open’ structure. These coefficients will be used only forthe design wind forces on the fascia of the gable ends and onscrim hung on the sides.

GCpi – (1E) = 0.71GCpi – (4E) = -0.54

9. qz = 0.00256KzKztKdV2I [psf]

10. p = qh[(GCpf) – (GCpi)] [psf] (net design wind pressure)

6.5.13 Design Wind Loads on Open Buildings with Monoslope, Pitched, orTroughed Roofs. 1. qh = qz from 9 above.

2. G=0.85 (gust effect factor)

3. CN=> (net pressure coefficient) – Load Case A & B

‘A’ CNW= 1.1 (windward side) perp. to ridge ‘A’ CNL= -0.33 (leeward side) perp. to ridge

‘B’ CNW= 0.167 (windward side) perp. to ridge ‘B’ CNL= -1.167 (leeward side) perp. to ridge

‘A’ CN= -0.3 parallel to ridge‘B’ CN= 0.3 parallel to ridge

4. p = qhGCN [psf] (net design wind pressure)

6.5.16 Design Wind Loads on Other Structures

1. qh = qz from 6 above. – This is evaluated at the height ‘z’ of thecentroid of area Af

2. G = 0.85 (gust effect factor)

3. Cf => Force coefficients from figure 6-22 – Open Signs & LatticeFrameworks.

SAP 2000 calculates areas, percent solid ratios, height ‘z’ forcentroid of area, and determines the wind force according thefollowing equation:

F = qzGCfAf (Eqn. 6-28)

Design Implementation Notes:

A. The 6.5.3 design procedure is used by SAP2000 to generate wind loadson the towers and on hanging payload. *See SAP2000 calculations.

B. The 6.5.13 design wind load is used in hand calculations to determinethe wind loads on the roof covering, which is transferred to the roofstructure. *See excel calculations.

C. The 6.5.3 and 6.5.16 design procedures are used by SAP2000 togenerate wind loads on the entire aluminum grid. *See SAP2000calculations.

Approximate Wind pressure calculated by SAP 2000 = 4.8psf. Wind

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pressure is applied to all surfaces of the trusses, including front and backof truss. This effectively produces a wind pressure of 9.6psf on theprojected surface area.

Wind pressure has been applied to the entire fly bay area to accommodate scrim,banners, or speaker arrays. The wind pressure used is the same as the gable endroof pressure, which is 2.5psf. This pressure corresponds with a 40 mph wind. Anyscrim, banner, or speaker array must be removed or lowered to the ground at windspeeds greater than 40 mph (see operations manual).

Payload:All items attached to the aluminum roof structure are considered payload. Allowableload tables for typical configurations, including mid span point load, third span pointloads, quarter span point loads, and uniformly distributed loads, are provided withthis report. Payload for the Fly Bays is also included in the load tables.

Loads have been applied to the bottom chords of the trusses. If heavy loads areplaced on the trusses they must occur at panel points only. If not, kickers from theload to the nearest panel point must be added. See attached load tables for allowableloading.

Wind Load and Payload Combinations

Wind from all four directions was considered in the design of the system. Wind 1: Wind on Upstage. Wind 2: Wind on Downstage. Wind 3: Wind on Stage Left.

Wind 4: Wind on Stage Right.Payload has been applied to three truss types in the structure. The three truss typesare: Sloping Truss, Flat Truss, and Sloping Ladder. The payload on the three trusstypes are placed in four typical arrangements – Load at mid-span, Load at third points,Load at quarter points, and Load uniformly distributed along entire length. Eachtypical arrangement is combined with the wind load. When combining loads such asself-weight (Dead Load), wind (Wind Load), and payload (Live Load), the loadcombinations defined by ASCE 7 are used.

Load combinations per ASCE 70.6D + W (Dead load due to the known weight of the truss

structure. Additional dead loads are not included.) D + L

D + 0.75L + 0.75W

Additional Factor:ANSI E1.21 – A3.2 Non-mandatory – 0.85 repetitive use factor forminor damage occurring the trusses through assembly, use, anddisassembly.

Based on ASCE 7 combinations and repetitive use factor, the followingcombinations are used as inputs in SAP 2000:

0.6D + 1.176W (1/0.85 = 1.176)D + 1.176L (1/0.85 = 1.176)D + 0.88L + 0.88W (1.176 x 0.75 = 0.88)

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Site Requirements for 6 Post Roof Top

Ground surface under tower (post) and tower outriggers must have a safe bearingcapacity not less than 1,500 lbs./sq.ft. (psf). Wood or other suitable cribbing must beplaced under the tower bases measuring 26”x26” min., and under the outrigger padsmeasuring 10”x10” min. If other site conditions are encountered, the cribbing sizesmay be proportioned accordingly by a licensed professional. For engineeringpurposes, the 6 tower reactions are each 7,000 lbs and the outriggers have a reactionof 1,000 lbs each.

Installing guywires from the top of the four corner towers to the ground is requiredunder normal use and according to the operations manual. Two additional guywiresmust be attached to each of the fly bay towers. Guywires for the roof top are to havea minimum working load capacity of 6,800#. Guywires for the ends of the fly baysmust have a minimum working load capacity of 1,800#.

The (8) roof top guywires wires must be strung at an angle of 45 degrees from thecorner of the tower down to the ground. The wire may be offset from the line of thetower no more than 6 feet. (See drawing). They must be attached to the head blockchannels and preloaded (tensioned) to not more than 100 lbs. each.

The (4) fly bay guywires must be strung at an angle of 15 to 20 degrees from vertical.They must be attached to the head block channels and preloaded (tensioned) to notmore than 100 lbs. each. See drawing for anchorage location.

Adequate ballast must be provided to resist the wind forces. The roof top guywireforce @ 40 mph wind speed is 3,300 lbs. This should be considered a minimumrequirement. It is highly recommended that ground anchorage or properly designedballast be used to resist a 90 mph wind speed. The guywire force @ 90 mph is6,800#. We recommend a factor of safety of 2.0 be applied to the breaking strengthof the guywire cable. That equates to a 1.36 ton working load at a factor of safety =5.0.

Truss Construction Information (Analysis Input Nomenclature)

Stage Roof Top consists of standard 26”x30” bolted end trusses and 16” towertrusses.The tower bases consist of outriggers placed at 45 deg from each of the four cornersof each tower.

It is paramount that the trusses used to construct the roof top conform with the trussdata used to analyze the system. We have provided the individual truss memberinformation for use in verifying the trusses used are appropriate. It is ourunderstanding that the truss information we have used is considered an industrystandard. However, this information must still be verified by the installer.

Each member of each truss is grouped within the software model and each group isassigned a section property. The following is a list of members and groupsreferenced in SAP 2000.

Member Group Names and Associated Member Sizes (6061-T6 Aluminum)Main Truss Sections:

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91in_main_chord_lines 2” dia x 1/8” wall Alum. Pipe

91_diags 1” dia x 1/8” wall Alum. Pipe

91in_horizontal s 2” dia x 1/8” wall Alum. Pipe91in_ladder_end 2” dia x 1/8” wall Alum. Pipe

91in_truss_ends 2” dia x 1/8” wall Alum. Pipe

Sloping Truss Sections:

sloping_truss_bc 2” dia x 3/16” wall Alum. Pipe sloping_truss_TC 2” dia x 3/16” wall Alum. Pipe

sloping_truss_Diags 1½” dia x 1/8” wall Alum. Pipe

sloping_truss_horizontals 2” dia x 1/8” wall Alum. Pipe sloping_truss_verts 2” dia x 1/8” wall Alum. Pipe

Sloping Ladder Truss Sections:

Sloping_Ladder_Main_chords 2” dia x 3/16” wall Alum. Pipesloping_ladder_mid_rail 2” dia x 3/16” wall Alum. Pipe

sloping_ladder_diag 1½” dia x 1/8” wall Alum. Pipe

Apex Ladder Truss Sections: apex_main_chord 2” dia x 3/16” wall Alum. Pipe

apex_mid_rail 2” dia x 3/16” wall Alum. Pipe

apex_diags 1½” dia x 1/8” wall Alum. Pipe

Tower Sections: tower_main_chord_line 2” dia x 3/16” wall Alum. Pipe

Tower_diags 1” dia x 1/8” wall Alum. Pipe

tower_vertical_lines 2” dia x 1/8” wall Alum. Pipe

tower_end_lines 2” dia x 1/8” wall Alum. PipeSleeve Block Sections:

sleeve_main_chords 2” dia x 1/8” wall Alum. Pipe

sleeve_block_ends 2” dia x 1/8” wall Alum. Pipesleeve_block_top_ring 2” dia x 1/8” wall Alum. Pipe

sleeve_block_bottom_ring 2” dia x 1/8” wall Alum. Pipe

sleeve_block_caster_assembly 2” dia x 1/8” wall Alum. Pipe

sleeve_extra 2” dia x 1/8” wall Alum. PipeHoist Assembly

Channels CS6x4.03 Alum. Channel

Chain Cable – Non Analyzed MemberTower Base

BaseLEG 2” x 3” x 1/8” wall Alum. Tube

-or- (2) C3x2.07 w/ 2” Gap Alum. Channel

BaseSTRUT 2” dia x 1/8” wall Alum. Pipe

Placement of Loads on the Truss Grid:Loads have been applied to the bottom chords of the trusses. If heavy loads areplaced on the trusses between panel points, kickers from the load to the nearestpanel point must be added. See attached load tables for allowable loading.

NOTE:The component governing the capacity of the structure is the bolted end of the trusswhen the bolts are placed in tension. If the truss becomes overloaded, then the jointsbetween trusses will indicate movement and the entire system must be immediatelyunloaded and inspected.

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Wind Loading Inputs in SAPWind 1 = North Wind (Upstage)Wind 2 = South Wind (Downstage)Wind 3 = East Wind (Stage Left)Wind 4 = West Wind (Stage Right)

Input Load Patterns Wind1/2-A-Roof (used for both Wind 1 and 2) Wind1/2-B-Roof

Wind1-Gable-WW (Windward on Gable) Wind1-Gable-LW (Leeward on Gable)

Wind1/2-Fascia (used for both Wind 1 and 2)Wind2-Gable-WW (Windward on Gable)Wind2-Gable-LW (Leeward on Gable)Wind3-A-Roof-WWWind3-A-Roof-LWWind3-Fascia-WWWind3-Fascia-LWWind3/4-GableWind3-B-Roof-WWWind3-B-Roof-LWWind4-A-Roof-WWWind4-A-Roof-LWWind4-Fascia-WWWind4-Fascia-LWWind4-B-Roof-WWWind4-B-Roof-LW

Input Load Combinations for Wind Only

Wind 1, Case A WIND1

Wind1/2-A-Roof Wind1-Gable-WW Wind1-Gable-LW Wind1/2-Fascia

Wind 1, Case BWIND1Wind1/2-B-RoofWind1-Gable-WW (Windward on Gable)

Wind1-Gable-LW (Leeward on Gable)Wind1/2-Fascia

Wind 2, Case A WIND2

Wind1/2-A-Roof Wind2-Gable-WW Wind2-Gable-LW Wind1/2-Fascia

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Wind 2, Case B WIND2

Wind1/2-B-Roof Wind2-Gable-WW Wind2-Gable-LW Wind1/2-Fascia

Wind 3, Case A WIND3

Wind3-A-Roof-WW Wind3-A-Roof-LW Wind3-Fascia-WW Wind3-Fascia-LW Wind3/4-Gable

Wind 3, Case B WIND3

Wind3-B-Roof-WW Wind3-B-Roof-LW Wind3-Fascia-WW Wind3-Fascia-LW Wind3/4-Gable

Wind 4, Case A WIND4

Wind4-A-Roof-WW Wind4-A-Roof-LW Wind4-Fascia-WW Wind4-Fascia-LW Wind3/4-Gable

Wind 4, Case B WIND4

Wind4-B-Roof-WW Wind4-B-Roof-LW Wind4-Fascia-WW Wind4-Fascia-LW Wind3/4-Gable

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OPERATIONS MANAGEMENT PLAN

Stage Roof Top – 6 Post with Fly Bays

Design wind criteria· Basic design wind speed 40 mph, 3 sec gust in accordance with ASCE 7

· Roof to be lowered to stage level at winds exceeding 40 mph, 3 sec gust andskins removed.

· Sound cabinets to be lowered to ground level at 40 mph, 3 sec gust andlaterally restrained

· All other hanging equipment to be lowered to stage level at 40 mph, 3 sec gustand laterally restrained

· Scrims on side walls to be removed at 40 mph, 3 sec gust

· Scrim or backdrop to be removed at 40mph, 3 sec gust

· Wind speeds are measured at 30 feet above ground level

Other DocumentationThis document shall be read in conjunction with the following documents

· Operating Manual provided by Manufacturer

· BSR E1.21 Entertainment Technology – Temporary Stage Roofs

· Signed and sealed Engineering Report by Engineer

Monitoring· The wind speed shall be monitored and records shall be kept on site

· The wind speed measurements shall be taken at the height of the roof structureabove ground, at a location where a true wind speed will be measured. Even ifrigging grid structure is within a partly enclosed structure (at least one openside), wind measurements must be taken outside of the enclosure.

· A competent, responsible person from Client will be present on site for thewhole period of the installation

· A regular liaison with the local airports and weather information centers will bemaintained to ascertain if any significant weather events are expected in the

immediate vicinity of the roof structures

PressuresIt should be recognized that the pressure and wind loadings on a structure areproportional to the square of the wind speed. Double the wind speed is four

times the pressure (force).

ActionsBased on the unpredictable nature of wind events in the United States, we

recommend evacuation of the area surrounding the Stage Roof Top when windspeeds are measured at 40 mph. The system can sustain full design wind

forces; however, results may be catastrophic if wind suddenly and unexpectedly

increases. A zone approximately 60 feet in all directions around the Stage Roof

Top is considered to be the danger zone. High winds may carry debris further,so this should be considered a minimum zone and responsible persons on siteshould consider a larger area for evacuation.

If sudden increases in wind speed are encountered, human life and safety mustbe held paramount to property damage and loss of profit. If the safety of thepersonnel working to lower the roof or removing components of the system is

ever questioned, complete evacuation of the area should be considered the onlyoption.

The actions listed are to be considered minimum requirements, and when

applicable, stricter site requirements may govern. The following actions will beundertaken by Client personnel on site when the 3 second wind speed gusts

approach the following speeds against a background of rising wind speeds.

Backdrop Level 1: Design wind load at 20 mph Personnel to be on alert

Level 2: Design wind load at 30 mph Personnel to be put on standby to remove the backdrop

Level 3: Design wind load at 40 mph Personnel to remove the backdrop

Side wall scrims and Fly Bay scrim Level 1: Design wind load at 20 mph Personnel to be on alert

Level 2: Design wind load at 30 mph Personnel to be put on standby to remove the scrims

Level 3: Design wind load at 40 mph Personnel to remove the scrims

Sound Cabinets

Level 1: Design wind load at 20 mph Personnel to be on alert

Level 2: Design wind load at 30 mph

Personnel to be put on standby to lower the sound cabinet

Level 3: Design wind load at 40 mphPersonnel to lower sound cabinet to ground and laterally

restrain

Stage Roof Top

Level 1: Design wind load at 20 mph Personnel to be on alert

Level 2: Design wind load at 30 mph Personnel to be put on standby to lower the roof

Level 3: Design wind load exceeding 40 mph Personnel to lower the roof and remove the skins

This document shall be considered only one part of a complete OperationsManagement Plan. The following elements should also be considered when

developing the Operations Management Plan for an event:

· Evacuation of the site

· Closure of site to public

· The stage itself (wind can cause uplift on stage decks)

· Delay towers

· FOH areaProvide drawings with the Operational Management Plan, a copy of which will

be kept on site and at Head Office of Client for ease of reference.