Method comparison
Alternative demolition methods: advantages, disadvantages, field experience
Hydraulic hammer, wire saw, splitting cylinder, conventional blasting or expansive mortar – a practical assessment of which method works in which situation.
Starting point
Why the choice of method is decisive
When demolishing rock and concrete, cost-effectiveness is rarely determined by material cost but by the surrounding conditions: neighbours, access, permitted vibration, working time windows, dust and noise regulations, and the risk of damage to existing structures. A method that is unbeatable in open terrain can be completely unsuitable on an inner-city site or in a plant that stays in operation.
The following overview ranks the common methods by the criteria that most often tip the scales in practice.
Comparison
The methods side by side
| Method | Noise | Vibration | Permit | Typical use |
|---|---|---|---|---|
| Expansive mortar | virtually silent | none | generally no blasting permit | residential surroundings, interiors, rock and mass concrete, confined and hard-to-access areas |
| Hydraulic hammer | very high | high | none, but noise and emission limits apply | large volumes without sensitive neighbours, good machine access |
| Conventional blasting | very high, short-lived | very high | blasting permit and licensed blaster | quarries, tunnels, large volumes with safety distances |
| Wire and wall saw | medium | low | none | precise cuts in concrete, openings, segmenting with crane removal |
| Hydraulic splitting cylinder | low | low | none | individual blocks, repeated splitting, immediate result |
| Crusher jaws / pulveriser | medium to high | medium | none | dismantling reinforced elements, material separation, secondary crushing |
Field experience
What practice shows
Hydraulic hammer: high output on unreinforced material with good access. In residential areas it is frequently the reason for complaints, vibration measurements and restricted working hours. In very tough rock and deep excavations, wear increases disproportionately.
Conventional blasting: unbeatable for large volumes, but requires a permit, safety distances, evacuation of the area, vibration assessments and often condition surveys of neighbouring buildings. On inner-city sites it is usually ruled out.
Wire and wall saw: very precise, ideal for openings and defined cuts. Drawbacks are water management and slurry, the need for anchor points and a high effort on thick or irregular elements.
Splitting cylinder: fast result and reusable tooling, but requires a hydraulic power pack, sufficient space and boreholes; large cross-sections need many placements.
Expansive mortar: excels wherever vibration, noise and permits are limiting. The sequence shifts working time into the night or into the waiting period: drilling and filling happen during the day, cracking happens without personnel. The prerequisite is a willingness to plan the reaction time into the schedule.
Classification
Expansive mortar in comparison
Advantages
- +No vibration – condition surveys and crack reports are often unnecessary
- +No bang and no flying rock, therefore minimal exclusion zones
- +Generally no blasting permit required
- +Work steps possible without heavy machinery and with small teams
- +The reaction runs unattended during closed hours and overnight
- +Separation lines can be defined very precisely via the drill pattern
Limitations
- –Result only available after 8–24 hours
- –Drilling effort largely determines time and cost
- –Less economical than blasting for daily volumes in the hundreds of cubic metres
- –Material consumption scales directly with borehole volume
- –Use is tied to a temperature range and product variant
Decision guide
In brief
Open terrain, large masses, permit in place: blasting. Good machine access, insensitive surroundings: hydraulic hammer. Defined cuts in concrete with crane removal: wire saw. Sensitive neighbours, interiors, rock without vibration, no permit obtainable: expansive mortar – in practice often combined with excavator and jaws for removal.
Application-specific details can be found under rock excavation, splitting boulders and concrete demolition.
FAQ
Frequently asked questions about method selection
+Which demolition method is the quietest?
Expansive mortar works virtually silently because separation is achieved by a slow build-up of pressure. Wire and wall saws are considerably quieter than hydraulic hammers but produce machine and water noise as well as slurry.
+When is conventional blasting the better choice?
For large volumes in quarry or tunnel operations, when sufficient safety distances are available and a blasting permit with a licensed blaster is in place. Its cost efficiency per cubic metre cannot be matched there.
+Is expansive mortar more expensive than hammering?
Per kilogram of material expansive mortar costs more than an hour of hammering, but overall it is often cheaper: no vibration assessments, no crack records on neighbouring buildings, fewer noise restrictions, less personnel and work possible during closed hours, because the reaction runs unattended.
+Can methods be combined?
Yes, and on larger projects that is the norm. Frequently an element is pre-split into segments with expansive mortar and then dismantled and removed with an excavator, crusher jaws or a crane.
Read on
Related topics
Expansive mortar
How it works, how it developed, drill patterns and the limits of non-explosive splitting – explained concisely.
Rock excavation
Building pits, road construction, tunnel re-profiling – breaking rock without vibration and without a blasting permit.
Splitting boulders
From field stones to 50-tonne blocks: drill, fill, wait – without flying debris and without vibration.
Concrete demolition
Separating foundations, plinths and mass concrete in a controlled way indoors and in populated surroundings.
Business location Liechtenstein
Highly industrialised, politically and financially stable, globally connected: the location behind BETONAMIT® and ROCKSPLIT®.
Mechanical application
Mix and pump BETONAMIT by machine: tonnes instead of kilograms – process, MAI mixing pump, water setting of 1.0–1.2 litres per 5 kg and safety.
Check the method for your project
Send us the volume, material and site conditions – we will tell you frankly where expansive mortar fits and where it does not.