Post-reserve stabilization of wood

Post-reserve stabilization of wood

DREVO Post-Reserve Timber Stabilization Protocol

Post-reserve stabilization is a set of operations performed after timber has been extracted from a long-term aquatic, marsh, bottom, or other wet reserve. Its purpose isnot just to dry wood, but to safely transfer the material from a state of perennial water saturation to a stable operational condition, preserving as much as possible the structure, size, strength, color and historical and material value.

For the DREVO Heritage Timber Program, this stage should be considered as a mandatory continuation of storage:

Reserve → Recovery → Wet Preservation → Diagnostics → Stabilization → Controlled Drying → Conditioning → Certification → Use.

The main principle:

Wood that has been successfully stored in reserve for 100-300 years can be damaged in a few days of improper extraction and drying.

Therefore, the moment of timber lifting is not the end of storage, but the beginning of the second critical technological phase.

1. Why can't you dry the extracted wood immediately?

After decades or centuries underwater, wood can differ significantly from freshly cut wood. Its pores contain water; some soluble substances may have been washed out; the mineral composition may have changed; localized microbiological degradation is possible; and the heartwood and sapwood may be in completely different conditions.

The situation is especially dangerous when the outer layers begin to quickly release moisture, while the central part of the massive trunk remains almost completely saturated.

The following arise:

surface shrinkage → internal stresses → radial cracks → warping → internal ruptures → irreversible loss of material.

The larger the diameter of the barrel, the more careful the transition should be.

For particularly large Heritage Logs with a diameter of 1–3 m, the stabilization process can potentially takeyears, not weeks.

2. Phase I — Recovery

Extraction must be carried out as a separate controlled operation.

Before lifting, the following are fixed:

Timber Passport ID;

coordinates and depth;

water temperature;

pH;

dissolved oxygen;

electrical conductivity/salinity;

state of bottom sediments;

barrel position;

condition of the bark;

presence of cracks;

biological fouling;

marking condition.

It is advisable to conduct an underwater 3D scanbefore moving the barrel.

This creates the latest record of its state directly in the reserve.

3. Phase II - Wet Transfer

After lifting the woodshould not be left open to the sun and wind.

This is especially true for old, water-saturated wood.

The barrel is immediately switched to Wet Transfer mode:

reserve → wet transport module → stabilization pool.

The following can be used for transportation:

closed wet containers;

waterproof covers;

swimming pools on transport platforms;

continuous spraying of water;

wet surfaces.

For particularly valuable objects, it is preferable to initially use water from the reservoir itself, rather than abruptly change the chemical environment.

4. Phase III – quarantine and primary diagnosis

Before the main stabilization, the wood is placed in a separate quarantine zone.

Research is being conducted:

A large trunk must not be considered as a single homogeneous object.

It is being created3D Moisture & Structural Map.

For example:

Surface → Sapwood → Transition Zone → Heartwood → Core.

5. Classification after extraction

After diagnostics, the wood receives an additional condition index.

I propose to introduce:

It is important not to confuse this indicator with the original Timber Reserve quality class.

For example:

TQ-A / RH-150 / PS-B

means: valuable timber of class A, which was in reserve for about 150 years, after extraction received the PS-B condition.

6. Phase IV – Water Stabilization

Initially, the barrel can be placed in a controlled pool.

The goal is not to dry it out, butallow the material to adapt after a change in environment.

Controlled by:

T° + pH + O₂ + conductivity + salinity + microbiology.

If necessary, the water is gradually replaced.

For example:

Reserve Water → 75% → 50% → 25% → Stabilization Water.

But this should not become a universal fixed scheme: the rate of change is determined by the analysis of the specific wood.

7. Desalination

Especially important for wood:

marine reserves;

brackish lagoons;

some mineral waters;

polluted bottom environments.

When drying, dissolved salts can crystallize inside the wood.

Therefore, controlled leaching of salts with regular measurement of water conductivity is used.

The process continues until the threshold set for a particular material is reached.

8. Gradually reduce humidity

After water stabilization, the longest stage begins.

The TREE principle:

Don't force the wood to dry too quickly. Create conditions where both interior and exterior areas lose moisture fairly evenly.

Several sequential modes are offered:

Water Saturated → Very High RH → High RH → Medium RH → Conditioning RH → Storage RH.

That is, the wood is not transferred directly:

water → dry pavilion.

Between them, a series of intermediate microclimatic zones is created.

9. DREVO Stabilization Pavilion

It would be appropriate to create a special pavilion for Heritage Timber.

It consists of sequential chambers:

Wet Chamber↓Transition Chamber I↓Transition Chamber II↓Slow Drying Hall↓Conditioning Chamber↓Heritage Timber Storage.

Each camera has its own control:

temperatures;

relative humidity;

air movement;

wood moisture content;

barrel mass;

deformations;

surface temperature;

the appearance of cracks.

The trunk gradually moves between zones only after the transition criteria are reached.

10. Air speed

One of the mistakes is to try to speed up the process with powerful fans.

For large Heritage Timber it is preferablevery soft and uniform air movement.

Do not allow a direct stream to hit one side of the barrel.

The air must wash the object from all sides.

This fits well with the concept already developed.DREVO Air Reserve: Natural drying under a controlled canopy or pavilion may be the last stage of the process, but not the first.

11. Mass control

A very useful parameter is the mass of the entire barrel.

Heritage Log is mounted on supports with built-in load cells.

We get:

M₀ → M₁ → M₂ → … → Mn.

DREVO AI plots a mass loss curve.

If the rate of water loss suddenly increases, the system can automatically:

increase air humidity;

reduce ventilation;

change the temperature;

stop the transition to the next stage.

Thus, mass becomes one of the main parameters for drying control.

12. Deformation control

Permanent measuring points are installed on large trunks.

Measured:

diameter;

circle;

longitudinal length;

existing cracks;

crack opening;

bend;

local shrinkage.

Laser 3D scanning can be used.

We receive digital models:

Geometry T0→ T1→ T2→ T3...

DREVO AI compares them and detects deformation even before serious, visible damage occurs.

13. Working with cracks

A small crack in itself does not mean wood loss.

The main indicator isthe speed of its development.

Therefore, a record is created for each significant crack:

Crack ID → Location → Length → Width → Depth → Growth Rate.

If the opening speed increases, the stabilization mode is adjusted.

For particularly valuable trunks, temporary mechanical stops, bandages or adjustable supports may be used, but they should not create local stress.

14. It is not necessary to dry the entire trunk.

This is a fundamentally important point.

If a trunk with a diameter of, for example, 2 m is intended for the production of boards, it may not be rational to stabilize it entirely for decades.

After the initial diagnosis, two strategies are possible.

Whole Log Stabilization

for museum objects, columns, sculptures, large structures and scientific storage.

Controlled Conversion

After preliminary stabilization, the trunk is sawn into large blanks, after which each one is stabilized separately.

The second option potentially significantly reduces the process time.

But cutting should be carried out only after determining the internal stresses and condition of the material.

15. Particularly degraded wood

Here, normal drying may not be possible at all.

If cell walls are severely damaged, water effectively maintains the material's geometry. If it is removed, the structure can collapse.

PS-C/PS-D may require specialized preservation methods, such as polymer impregnation, PEG-like preservation approaches, or other technologies chosen by the laboratory.

Such wood should be considered rather asarchaeological material, and not ordinary lumber.

16. Final conditioning

After the main drying, the wood is not yet considered ready.

It is maintained in a stable microclimate until an equilibrium state is reached.

Controlled by:

mass → moisture → dimensions → cracks → mechanical properties.

Only when the parameters stop changing significantly does the material move on to certification.

17. Final laboratory certification

Each batch is re-tested.

The following are determined:

density;

humidity;

modulus of elasticity;

strength;

hardness;

dimensional stability;

fiber condition;

chemical composition;

biological stability;

visual class;

Acoustic characteristics - for resonant wood.

After this the material getsPost-Reserve Certificate.

18. New Timber Passport Recording

The digital passport does not close after being removed.

On the contrary, a new part of the life cycle begins:

Tree → Harvest → Reserve → Preservation → Recovery → Stabilization → Material → Product.

The passport records the date of extraction, actual storage period, wood condition, CT/ultrasound results, chemical analysis, stabilization mode, mass loss graph, moisture graph, deformation, final mechanical properties and further use.

So in centuries it will be possible to understand not onlywhere the tree lay, but also what happened to him after the extraction.

19. DREVO Twin Log

The principle of the control twin becomes especially valuable here.

If two maximally similar barrels are placed in reserve at the same time:

Log A → recovery after 25 yearsLog B → continues to be stored.

The results of Log A stabilization allow us to change the forecast and storage mode of Log B.

Further:

25 → 50 → 100 → 150 → 200 → 300 years.

This provides a unique scientific basis for the long-term behavior of wood.

20. DREVO Post-Reserve Research Library

Not all recovered wood should be used commercially.

It is advisable to preserve samples from each scientifically significant object:

Cross SectionCore SampleSapwood SampleHeartwood SampleChemical SampleDNA SampleMicroscopy Sample.

They are included in the DREVO Heritage Timber Library.

In 100–200 years, future researchers will be able to re-examine the material using methods that do not yet exist today.

21. Three modes of post-backup processing

Within the framework of the program, it is reasonable to formally define three directions:

Each mode must have its own stabilization protocol.

22. Complete technological chain

Thus, the DREVO Heritage Timber Program receives a closed life cycle:

Growing Forest↓Tree Selection↓Sustainable Harvest↓Timber Passport↓Reserve Preparation↓10–300 Years Preservation↓Recovery↓Wet Transfer↓Quarantine↓Diagnostics↓Water Stabilization / Desalination↓Controlled Moisture Reduction↓Slow Drying↓Conditioning↓Laboratory Certification↓Heritage Timber Bank↓Architecture / Furniture / Instruments / Research / Heritage Objects.

The main principle of DREVO

The goal of post-reserve stabilization isnot to get dry wood as quickly as possible, but to preserve the maximum value that has been preserved over decades or centuries of being in reserve.

WOOD Shrub Reserve