Cranes

Depending upon the height of the building constructed, a determination will have to be made on the type of crane that should be used for this particular project. For heights of up to 200 feet, a mobile crane can be utilized. Once this height is exceeded, then a climber tower crane will have to be considered.

Exhibit 6-1

Logistics flowchart.

Exhibit 6-2

Site access plan.

Exhibit 6-1

Logistics flowchart.

Metal Stud Soffit Framing Detail
Loading/unloading area

HOIST #1

Labor and materials

HOIST #1

Labor and materials

Exhibit 6-3

Hoists, elevators loading dock plan.

Large projects might have multiple cranes operating simultaneously. Both the prime contractor and subcontractor could have a role in selecting the number, type, and location of these cranes. Factors might include:

1. Project schedule and attendant requirements for crane picks

2. Available area for picks from the street and movement within the site

3. Cost of crane and operator versus productivity gain

4. Potential interference between cranes in operation or with other equipment operating on the site

5. Need for the hook to reach where needed with requisite lift capacity

6. Needs of trades to work independently of other trades with respect to lift scheduling

7. Potential interference between space requirements for cranes taken out of service and poised for storm winds

8. Potential benefit of having one crane erect or dismantle another crane

9. Load bearing of the ground to support the crane and its lifting load

Exhibit 6-4

Crane locations.

HOIST #1

Labor and materials

HOIST #1

Labor and materials

For a crane sitting on a city street, the load bearing capacity below its base will have to be analyzed by a structural engineer. The effects of the crane on underground utility vaults, transportation systems, and foundations in the area will have to be considered. In some instances, a crane is supported on the building structure and the building must be designed to sustain the loads in combination with other loads that occur during construction. As the self-raising crane starts "growing," then it has to be tied into the building structure for stability and the building must be designed to support its load. This usually occurs at every 60 to 100 feet. See Exhibit 6-6 for tower crane stages.

Exhibits 6-7 to 6-10 show various components of the crane including:

• Climbing crane with structural support (Exhibit 6-8)

• Crane's collar support to structure (Exhibit 6-10)

Item

Details

Requirements

Logistics

Logistics plan Hours of operation

Transportation stops

Moratorium periods

Field office and shanties

Field office Consultant's office Sidewalk protection Shanties Storage areas

Container Storage

Special yards

Cylinder storage

Office power supply Loading dock Off-site storage

First aid office Temporary toilets

Utilities

Safety & Site Prep

Safety nets

Site security

Plan of total area Hours that the site will be open and any municipal restrictions Bus, subway, and tram stops must be evaluated

Restricted days when construction activitity has to be curtailed

For CM/GC/Subcontractors/Owner/Consultants.

Location of offices and shanties relative to site entrance

Administrative offices

Offices for the architects and engineers

Safety for pedestrians

Subcontractors office and storage

Location for storing large pieces of equipment

Storage for containers for demo truck pick up

For the on-site fabrication of materials and staging of equipment Acetylene torch and concrete cylinders

Storage of flammable and hazardous materials

Power for field office and shanties

Off load of equipment and material

To be considered because of limitations on site space

Location for assisting injured workers

Toilets for the workers

Location of temporary bathrooms

Heaters and A/C for construction shanties

Telephone, fax, Internet service for CM and trades

Utilizing permanent systems for use during construction

Nets required for safety of workers and to catch any falling objects Security of site and offices

Exhibit 6-5

Logistics checklist.

(Continued)

Exhibit 6-5

(Continued)

Item

Details

Safety & Site Prep

Guards booth Security fence

Security gates Bridges

Security badges Evacuation plan Emergency system

Requirements

To control site access

For securing the area from theft and access

Secure access for workers and trucks Safety for pedestrians Badges required to be worn by all persons working on the site Plan established for vacating the site in case of a problem Communication system for notification of fire, collapse, etc. Emergency contact information Communication system on site OSHA protection, signage and logs

Temporary Services and Facilities

Temporary lighting For security and safety

Temporary power For running the operation

For demolition and abatement

For excavation and foundation

For hoists

For loading dock

For hoist tower lights and outlets

For sidewalk bridge and sheds

Temporary light and power for construction

For specialty equipment

For elevators

Availability of permanent power For saws

Welding equipment Rigging equipment Derricks Project signage Mixing equipment For water pump

Temporary water and pump Temporary water for construction

Water barrels for water use and drainage

Item

Details

Requirements

Water

Roofing

HVAC

Security

Siamese connection to feed stand pipe Temporary roof Temporary heat

Interim cooling and dehumidification Protection of facilities

Exhibit 6-5

(Continued )

Maintenance

(General) Maintenance of temporary systems

Work that may affect the Transit Authority work and zone of influence Maintenance of temporaty facilities and standby operating personnel Of permanent facilities used during the construction process Refurbishment of equipment and extension of all guarantees and warranties

Fire Protection

(General) Fire resistant construction

Sprinkler protection of shanty areas Stand pipe Fire department requirement

Fire extinguishers Siamese connection Location for fire truck connection

Access to fire hydrants

Signage & Traffic

(General)

Authorities Demolition

Detours

(Continued)

Contractor's name and emergency numbers

Department of Buildings contact information

Demolition subcontractor's name and emergency numbers

Interim use of building loading dock

Pedestrians directional

Sidewalk closing

Lane closing

Direction of the flow of traffic Bus lanes and stops Subway entrances and exits Visibility of traffic signage or relocation of same

Exhibit 6-5

(Continued)

Item

Details

Requirements

Permits

Logistics

Construction Labor

Required permits for temporary facilites used during construction

Permits for storage

Permits required for implementing the logistics plan Permits from regent Building Department and Transit Authorities Overtime work permit

Sidewalk closing Lane closing Relocation of hydrants Relocation of parking meters Relocation of affected transit signage Installation of personnel hoists Installation of material hoists Installation of barricades in roadway and cross-walks Relocation of bus stops Relocation or closing of subway entrances

Sidewalk bridge and shed

Scaffolding

Dumpsters

Trailers

Construction materials Portosans Vehicles Crane permit Derrick permit Rigging permit

Vertical Transportation/ Sidewalk Bridge/Sheds

Parking for pumper Parking of trucks Sidewalk closings

Street closing

Location of truck for pumping concrete Concrete, steel picks, equipment picks Closing of pedestrian sidewalks for projects requirements Closing of streets for project requirements

Item

Details

Requirements

Road lane closing Location of hoist

Elevators

Crane Derricks

Parking of equipment or storage area Internal or external to building? Construction personnel hoists Construction material hoists Combination personnel/material hoists Lifting labor and materials Loading dock for hoists Barricades for hoists and loading dock Signange

Flashing yellow caution lights Concrete foundation pad for hoist Tie backs of hoists to the structure Runaways from hoist tower to building Power for lighting and outlets at hoist landings and loading dock Engineering Sidewalk closing Lane closing

Direction or flow of traffic Zone of influence of the hoist for sidewalk bridge

Sidewalk bridge for pedestrian protection Lighting under sidewalk bridge Anchorage of sidewalk bridge Weather-resistant enclosure at hoist entrance to building Ramps from hoist entrance into building

Coordination of hoist location with permanent building facilities Use of hoists for construction of tenant fit up program Schedule for the availability of permanent service and passenger elevators

Interim use of service elevators Interim use of passenger elevators Operating criteria Operating criteria

Exhibit 6-5

(Continued)

Exhibit 6-6

Tower crane Tower crane placement phases.

'TO. Builiding

Phase 1_

Tower care serve floors 10-20 (Including lonely and Mezzanine) Completion of Phase 1 Tower crane moves to 21st Floor

Phase 2

Tower crane serve floors 22-28

Completion of Phase 2 Tower crane moves to 28 A Floor

Phase 3_

Tower crane serve floors 28A-34

Completion of Phase 3 Tower crane moves to 35th floor

SAFETY NET STAGES

Phase 4_

Tower crane serve floors roof for

Completion of Phase

Disassembly and removal of tower crane

Phase 1_

Tower care serve floors 10-20 (Including lonely and Mezzanine) Completion of Phase 1 Tower crane moves to 21st Floor

Phase 2

Tower crane serve floors 22-28

Completion of Phase 2 Tower crane moves to 28 A Floor

Phase 3_

Tower crane serve floors 28A-34

Completion of Phase 3 Tower crane moves to 35th floor

Exhibit 6-7

Climbing crane cab.

Exhibit 6-8

Climbing crane with structural supports.

Exhibit 6-8

Climbing crane with structural supports.

Exhibit 6-9

Crane structure.

Exhibit 6-9

Crane structure.

Exhibit 6-10

Climbing crane-support collars.

CRANE SAFETY

Crane safety is an especially poignant issue in the urban environment. Accidents in cities receive prominent news coverage that has prompted state legislatures to consider strengthening their regulations. A major crane accident occurred in New York City on March 15, 2008, killing seven people. On May 31, 2008, another crane accident occurred in New York City killing two construction workers. See Chapter 5 for more information on crane safety. California, New York, the State of Washington, and Dade County in Florida have enacted strong crane laws and other jurisdictions, including OSHA, are weighing the enactment of new rules. New York City and California have the most stringent crane requirements:

1. Only approved crane models are permitted to be used. Each crane must be registered and inspected annually.

2. Crane operators and riggers are licensed. Tower crane erection dismantling and climbing requires a licensed rigger.

3. Crane installation on new buildings must be engineered and the engineering is then reviewed by the building department.

4. Crane installations must be inspected by either a professional engineer or a building department inspector.

5. All "jumping" of cranes must be observed by a building department inspector and/or a licensed master rigger and independent crane consultant.

In 2008, 220 cranes were operating in New York City. Even with New York City's oversight, several accidents still occurred with cranes. After the May 30, 2008, incident, the New York City Department of Buildings closed down all construction sites that were using jumping cranes. These sites were not to continue work until a thorough inspection was made of every section and connection of each crane. This inspection caused major delays to the projects. Safety is the key to successful projects.

OSHA (Occupational Safety Health Administration) has jurisdiction for cranes on construction sites (Regulation Standards-29CFR Standard Number 1926.550). The ANSI B30 standards cover various types of cranes. These standards are not law but they are often treated as such by municipal building departments and they have high standings in the courts. A contractor has many incentives to keep safety of the cranes a primary objective and to heed these standards:

1. Problems with the crane can seriously affect the schedule.

2. The governing authorities can mandate heavy fines.

3. Insurance companies will increase premiums.

4. Bond sureties will increase bonding premiums or may decide not to bond the contractor.

5. Reputation can be tarnished.

6. The authorities may impose additional oversight.

7. The CM/GC could have a problem in obtaining "good" bids by subcontractors on future work.

8. With any injury or death, productivity of the workers on the job site decreases.

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Project Management Made Easy

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