Best Practices for Temporary Shoring During Bridge Deconstruction
The 40% Training Gap and What It Costs
NCHRP Synthesis 536 Chapter 5 found that only 40% of state DOTs provide specialized demolition training to bridge engineers and inspectors. That statistic points to a gap that temporary shoring failures often fill: when engineers have not been trained specifically in demolition-phase structural behavior, shoring decisions default to construction-phase experience — which may be inadequate for the reversed load conditions of deconstruction.
Temporary shoring bridge deconstruction work requires a different engineering approach than erection shoring: load cases reverse, and the structural shoring system bridge removal carries forces that construction-phase falsework was never sized for — including sudden load spikes when a span is severed and its dead load transfers immediately into the support below. Shoring tower placement bridge demolition demands awareness of conditions that erection never faces: scoured riverbeds, broken pavement, and soft soil beneath removed footings. Every interim support structure bridge demo is specified for the actual partial-structure load state, not for the incrementally increasing forces of new construction.
Shoring that was sized for erection loads does not automatically work for demolition loads. During construction, loads increase incrementally as each element is added. During demolition, loads can spike suddenly as a span is cut and its dead load transfers immediately into the shoring below. The AASHTO Guide for Bridge Temporary Works establishes the national specification for designing the structural shoring system for bridge removal — a specification that presupposes the shoring engineer has access to the full load state at each phase, including the demolition phases. That is the information the Demolition Symphony Planner provides. The falsework bridge demolition support system must be designed for the specific load cases of each demolition phase — a requirement that presupposes the shoring engineer is reading from the same score as the demolition sequence engineer.
Scaffold USA's shoring guidance identifies solid bearing surface as a non-negotiable requirement for shoring tower placement at bridge sites — a condition that is obvious in a controlled construction environment but often compromised at a demolition site by soft ground below a removed footing, scoured riverbed below a waterway pier, or broken pavement below an urban overpass. Each of these conditions must be assessed before the shoring tower is placed and verified before it accepts load. Falsework supporting bridge demolition above active lanes carries an even higher standard: impact loading from passing vehicles must be included in the design, and bearing conditions must be assessed for the full duration of the falsework's service in the demolition sequence.
Writing Shoring Into the Score as Required Notes
The Demolition Symphony Planner treats every temporary shoring installation as a required note in the score — a notation that must appear in the sequence before the measure it supports can open. A span cannot be cut until the shoring note for that span's pier is confirmed. A pier cap cannot be removed until the cap-transfer shoring note is confirmed. This structure mirrors how a musical score enforces the orchestra's preparation before a key passage: the note must be held before the next phrase begins.
Shoring Tower Specification by Phase. Different phases impose different loads on temporary support. Caltrans Bridge Temporary Shoring Chapter 6 details structural design requirements for shoring towers at each load stage. The Demolition Symphony Planner records each tower's governing phase load — the maximum force the tower will experience across all phases it is active — and annotates the score at the measure where that governing load occurs. The structural engineer of record reviews the governing load annotation, not a separate shoring calculation buried in the project file.
Falsework Over Active Lanes. Where temporary shoring or falsework spans over live traffic lanes below an overpass being demolished, the design requirements ratchet upward. Impact loading from passing trucks must be included in the design, and any deflection limit must be verified against the clearance available. Caltrans Falsework Manual Chapter 1 notes that two-thirds of states require PE-sealed plans for falsework over active lanes. The Demolition Symphony Planner marks falsework-over-traffic measures with a seal-required notation, triggering the appropriate review workflow before the measure opens.
Shoring Continuity Over Rail. The BNSF Railway Bridge Demolition Guideline requires continuous shoring over active rail during bridge demolition operations. This is not a suggestion — it is a precondition for demolition activity above the rail corridor. The Demolition Symphony Planner writes rail-corridor shoring as a standing precondition note that remains active across all measures where structure exists above the active rail zone.
Load Transfer Confirmation Between Measures. Shoring towers that are installed correctly but not verified for load transfer before the next phase begins create a false sense of security. The sequence discipline required at each phase connects directly to the load transfer analysis work that defines what the shoring must carry at each intermediate state. The Demolition Symphony Planner links shoring notes to their corresponding load transfer annotations, so the structural review at each gate covers both the shoring capacity and the load it is accepting.
Coordinating shoring with pier column removal. Temporary shoring is most critical during pier column removal, when the pier cap must remain stable after columns below it are removed. The shoring sequence for pier cap support is written as a sub-sequence within the pier measures: tower placed, load transfer confirmed, column extraction begins, cap supported, column fully removed, cap transfer verified. No step opens until the prior step is confirmed.
Advanced Shoring Tactics for Constrained Sites
Bearing surface remediation as a precondition measure. When ground conditions below the planned shoring location are compromised — scoured riverbed, soft soil, broken pavement — the score includes a bearing surface remediation measure before the shoring installation note. This prevents crews from placing shoring on inadequate bearing conditions because the structural timeline pressures them to skip the remediation step.
Shoring removal as a scored sequence. Temporary shoring is removed in reverse installation order, and that removal sequence carries its own structural risks. Removing the last shoring tower too early, before the final span elements are clear of the bearing zone, can cause unintended movement. The Demolition Symphony Planner writes shoring removal as a scored sub-sequence at the end of the structural movement it supported, with the same gate-condition discipline applied to removal steps as to installation steps.
Load redistribution monitoring during shoring transitions. When a shoring tower is repositioned between phases — moved from pier 2 to pier 3 as work advances — there is a transition window where the redistribution of load between towers must be monitored. Strain gauge readings at the repositioned tower confirm that the new bearing condition is accepting load as designed. The Demolition Symphony Planner writes monitoring gate annotations at each shoring transition, preventing the transition from being treated as a simple logistics move.
Connecting to equipment planning. Teams with experience in inventory heavy equipment plant strip-out will recognize the resource-tracking discipline. Shoring towers, like heavy equipment in a plant decommission, must be tracked through the project — when they are deployed, what they are rated for, and when they are released. The Demolition Symphony Planner's shoring register tracks each tower's deployment history alongside the structural phases it supported.
Mock-up review before mobilization. FHWA safety guidance on bridge demolition recommends reviewing temporary support systems in advance of mobilization. The Demolition Symphony Planner's score provides the reference document for that review: every shoring note, load annotation, and gate condition is visible before any equipment arrives, allowing the project team to identify conflicts between the shoring plan and the site constraints.
Shoring as the Score's Safety Infrastructure
The structural shoring system for bridge removal is not auxiliary to the demolition score — it is its safety infrastructure. Every span removal measure, every pier column measure, and every pier cap transfer measure in the score depends on a correctly placed and correctly loaded interim support structure for bridge demolition as its prerequisite. Without shoring noted as a required score element, the sequence appears executable when it is not.
The Demolition Symphony Planner makes shoring a first-class element of the project score. It is designed, annotated, reviewed, and confirmed at every phase where it matters — not assumed and not improvised. The interim support structure notation in the score creates an auditable record: every shoring tower's design, placement, and load transfer confirmation is traceable through the measure-by-measure gate history, so the project team's compliance with temporary works specifications is documented in the same record as their structural sequencing decisions.
Temporary shoring for bridge deconstruction that is tracked in the score also eliminates the category of incident caused by premature removal — where a shoring tower is relocated or de-loaded before the structural action it was supporting is complete. When shoring removal is a scored measure with a confirmed pre-condition (the dependent structural action is complete and the load has been transferred to the permanent structure or the next shoring configuration), the sequence cannot advance to shoring removal until those conditions are documented as cleared. Falsework for bridge demolition managed through gate notation closes the gap between what the shoring design assumed and what the field team actually does.
Score the Shoring Before You Plan the Cuts
Bridge and overpass demolition teams should write their shoring plan into the demolition score before any span removal or pier work is sequenced. The shoring notes define the structural envelope within which the rest of the sequence operates. Build your temporary shoring sequence with the Demolition Symphony Planner and give your bridge and overpass demolition team a score where every shoring tower placement, load transfer gate, and falsework verification is written in before the first cut is planned — eliminating the improvisation that turns temporary works into structural emergencies.
Shoring tower placement records and load transfer confirmations managed through the Demolition Symphony Planner's gate system also satisfy the temporary works documentation requirements that engineering specifications and owner quality programs impose on bridge demolition temporary support systems. When interim support structures for bridge demolition are tracked as scored precondition elements — with design confirmations, placement verifications, and load transfer gates logged against each structural phase — the project record demonstrates that the temporary works program was engineered, confirmed, and monitored throughout the demolition sequence. Join the bridge and overpass demolition teams that are replacing disconnected shoring documents with a single scored sequence. Start your shoring plan with the Demolition Symphony Planner and give your bridge and overpass demolition team a temporary shoring score where every tower placement, load transfer gate, and falsework verification is part of the plan before the first cut is authorized.