The crane jib boom is the central load-bearing and reach element of a crane. It defines how far and at what angle loads can be traveled, lifted, or repositioned. In demanding projects such as concrete demolition and special demolition, building gutting and cutting, rock excavation and tunnel construction, natural stone extraction as well as special operations, the crane jib boom determines accessibility, cycle times, and safety. Especially when precise tools such as concrete demolition shears or rock and concrete splitters are used, the crane jib boom governs safe positioning, load handling, and the interaction with hydraulic power units and rigging.
Definition: What is meant by a crane jib boom
A crane jib boom is the load-bearing jib system of a crane that brings the load-handling device (e.g., hook, hook block, trolley) into a defined working radius. The jib boom transfers forces and moments from the load, self-weight, wind, and dynamic movements into the upper and lower crane structure. Depending on the design (telescopic crane jib boom, lattice mast, luffing jib, tower crane jib boom), the kinematics vary: boom length, boom angle, outreach, and any auxiliary jibs determine the load chart. Load capacity is always a function of outreach, configuration, and environmental conditions.
Types and construction of crane jib booms
Crane jib booms can be grouped into a few basic types from a structural perspective. Selection is based on application profile, required reach, loads, and site geometry. For deconstruction and demolition, high precision and low vibration are often required so that tools such as concrete demolition shears, combination shears, or Multi Cutters can be guided in a controlled manner.
Telescopic crane jib booms
Telescopic crane jib booms consist of nested, high-strength steel sections that are hydraulically extended. Advantages include short setup times, variable length, and compact transport dimensions. They are often combined with auxiliary jibs (tip, jib) to increase reach or bridge obstructing building elements.
Lattice-mast and luffing crane jib booms
Lattice-mast jibs are assembled from individual mast sections. They are lightweight, torsionally stiff, and enable large reaches with favorable self-weight. Luffing crane jib booms (luffing jib) allow adjustment of the boom angle at constant length. In urban deconstruction, the luffing jib is advantageous to avoid collisions and to guide loads without a large slewing radius.
Crane jib booms of tower cranes
On tower cranes with luffing or flat-top jibs, load handling is performed via trolleys. This allows very sensitive pre-positioning of tools, components, or demolition loads. For building gutting and cutting work, hydraulic power packs can be placed on floors and supply tools such as concrete demolition shears, steel shears, or cutting torches.
Load capacity, load moment and load chart
The planning and executing parties must safely control load capacities. Decisive are the load moment and the load chart of the respective crane in the chosen crane jib boom configuration. The following influencing factors are relevant in practice, especially when tools and components are alternately handled on the hook:
- Outreach (working radius) and boom angle
- Boom configuration (telescopic length, jib, guying)
- Self-weight of rigging and tools (e.g., concrete demolition shears, rock and concrete splitters, hydraulic demolition shears)
- Dynamic additional loads from acceleration, braking, and oscillations
- Wind loads and aerodynamic effects of large-surface components
- Ground, support footprint and crane standing (bearing pressure, settlements)
In deconstruction work, the effective load is often higher than the component weight alone, since accessories, hydraulic hose lines, and power unit lines are carried along. In addition, impact and jerk loads can occur when releasing components. Conservative planning, the selection of suitable rigging, and controlled working minimize these effects.
Crane jib boom in concrete demolition and special demolition
In deconstruction, crane jib booms are used to pre-position components, separate them in a controlled manner with concrete demolition shears, or crack them with rock and concrete splitters with low pressure. The crane takes over safe holding and traveling while the tool cuts or splits. This reduces noise, vibration, and dust, which is advantageous in sensitive environments.
Selective deconstruction in existing structures
During building gutting, hydraulic power packs are relocated by crane onto slabs. From there, they supply tools via hose lines. The crane jib boom is used to follow up with protective and separating elements and to transport away components that have been separated. Concrete demolition shears are suitable for nibbling balcony slabs, lintels, and parapets when they are held under load and separated section by section.
Cutting, separating, holding
When cutting reinforcement, beams, or tanks, steel shears, Multi Cutters, and cutting torches are used. The crane jib boom holds the component free of load to avoid pinching and to relieve the cut. This reduces the risk of pendulum movements and uncontrolled fracture edges.
Rigging tools and components to the crane jib boom
Load handling at the crane jib boom requires suitable rigging, lifting points, and clear load control. The following principles support stable work with tools:
- Clarify weight and center of gravity: fully account for tool, rigging, and media lines.
- Prefer positive-locking, redundant slinging methods; observe adequate sling angles.
- Guide with taglines to control slewing and rotation.
- Low-vibration working method: smooth travel, gentle hoisting/lowering, short outreach with heavy tools.
- Keep the hazard zone clear, use unambiguous signals, and ensure clear role allocation between crane and demolition teams.
For tools such as concrete demolition shears, defined guidance is essential to apply biting forces precisely. Rock and concrete splitters are often delivered via the crane jib boom into core drill holes, shafts, or to hard-to-reach components and used there.
Reach and access in rock excavation and tunnel construction
In rock excavation and tunnel construction, controlled energy input is crucial. Where vibrations and blasting are limited, rock wedge splitters can be positioned with the help of the crane. The crane jib boom bridges uneven terrain, slopes, or shaft heads and allows safe, vertical placement of the devices. By operating hydraulic power packs at a safe distance, operation is spatially separated while the crane holds the load steadily.
Natural stone extraction and special operations
In quarries or in special operations with limited access, the crane jib boom enables rapid positioning of splitting tools in drilling rows. Multi Cutters can also be used to sever secondary parts or to cut free the quarry face. The low self-weight of many tools combined with precise load control is an advantage when the tip load of the crane is limited.
Technical parameters of a crane jib boom
Several parameters are decisive for planning. They determine the suitability of the crane jib boom for the respective tools and components:
- Boom length, telescopic sections, jib configuration
- Maximum and minimum outreach, working diagram
- Tip load and load-moment limitation
- Deflection and permissible vibration amplitudes
- Guying, sheave heads, rope routing, and trolley parameters
Low deflection and a stiff setup improve the guidance of concrete demolition shears, especially when positioning precisely at edges or reinforcement zones. Low-vibration crane jib boom configurations are often advantageous in urban deconstruction.
Work preparation: location, support, and cycle
The crane standing position determines the possible outreach. Support pressures, substructure, and effects on underlying slabs must be clarified at an early stage. For phases with concrete demolition shears or rock and concrete splitters, a cycle plan that coordinates the interplay of positioning, cutting/splitting, and removal is helpful.
Matching crane and tool performance
The performance data of the tools (e.g., thrust force, cutting force, splitting pressure) should harmonize with crane capacity at the respective outreach. An overly heavy tool at large outreach limits reserves for dynamic effects. A lighter tool with sufficient power can be guided more precisely at the limit of outreach.
Power supply and media routing
Hydraulic power packs supply concrete demolition shears, hydraulic demolition shears, Multi Cutters, or rock wedge splitters. They are often transported via the crane jib boom to the place of use or placed on intermediate levels. Hose bundles must be protected against abrasion, relieved, and routed so that no additional pendulum dynamics arise. A clear separation of load path and media path increases safety.
Safety, environment, and regulations
Safe crane operations require qualified personnel, suitable rigging, and compliance with applicable standards and operating manuals. Weather (especially wind) must be assessed before and during lifting. In deconstruction, protective measures against dust, noise, and falling parts must be implemented. For work above traffic or protected areas, additional safety and closure concepts must be provided. Information in operating manuals and load charts must be strictly observed; project-specific approvals are issued based on a technical assessment.
Combination with carrier machines
Tasks are often efficient when crane jib booms and carrier machines work together. Excavator attachments take on material-intensive primary demolition; the crane positions concrete demolition shears for precise separation cuts, lifts out separated elements, and guides them away in a controlled manner. Cutting torches, steel shears, and hydraulic demolition shears sever structures while the crane jib boom holds the parts free of load.
Practical selection criteria for the right crane jib boom
- Site geometry: obstacles, building heights, access routes, courtyards
- Load spectrum: typical component weights, tool masses, tip loads
- Reach vs. precision: required outreach, permissible pendulum paths
- Setup and cycle times: frequency of re-rigging, need for jibs
- Subsoil and support: bearing capacity, temporary reinforcements
- Environmental requirements: noise, vibration, dust
Typical sources of error and how to avoid them
- Underestimating the self-weight of rigging and media lines
- Working close to load limits without reserves for dynamic effects and wind
- Lack of taglines and uncontrolled rotation on the hook
- Insufficient coordination between crane operator and tool operator
- Missing intermediate supports for long telescopic sections or jib configurations
Terminology and metrics at a glance
- Outreach: horizontal distance between slewing center and load plumb line
- Load moment: product of load and outreach, decisive for capacity
- Tip load: maximum load capacity at the crane tip in a defined configuration
- Luffing range: angle range within which the boom can be adjusted
- Load chart: table/diagram of permissible loads depending on outreach and configuration
Through the interaction of crane jib boom, tool, and working method, demanding tasks in concrete demolition, building gutting, rock excavation, natural stone extraction, and special operations can be executed safely, precisely, and efficiently. By choosing a suitable jib configuration, maintaining clean load control, and using concrete demolition shears as well as rock and concrete splitters in a coordinated manner, a controlled, plannable workflow is achieved.