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How to strengthen walls made of aerated concrete. Strengthening a wall made of foam blocks. High Level Gain

At the stage of building a house made of aerated concrete blocks, additional reinforcement of door and window openings. This is necessary to strengthen the entire structure, prevent the formation of cracks or other defects on the walls of the building that may appear during further exploitation. For this purpose they are used different kinds construction crossbars, differing in cost, speed and ease of installation, and durability. Lintels over windows in a house made of aerated concrete solve many pressing problems, but before using them you should familiarize yourself with some of the nuances and important characteristics.

Types of lintels for walls made of aerated concrete blocks

Depending on the tasks assigned, they can be used in construction the following types jumpers.

Made from reinforced aerated concrete

They are used in the construction of buildings made of cellular concrete blocks. They are often used to cover load-bearing walls of residential and public buildings up to four floors. Equipping box openings with aerated concrete lintels in load-bearing walls Suitable for houses whose height does not exceed 17 meters. The advantages of using aerated concrete beams are as follows:

• high speed of work;
• small weight;
• a clear and smooth surface that can be decorated with paint or thin-layer plaster;
• absence of “cold zones”.

The disadvantage of these products is the high price, but it is compensated by other advantages.

Reinforced concrete

Made from steel rods and heavy concrete mortar. Such devices have a wide range of applications. They are used in construction for floors, and also as supporting structures. The main advantage is their availability and low price. The disadvantages of reinforced concrete lintels for aerated blocks include high thermal conductivity and significant mass.

Wooden

Such additional devices are used in the construction of houses made of brick, wood or cellular concrete material. The main requirements for buildings when installing wooden lintels is the presence of ceilings with wooden floor. The material used is first thoroughly dried and treated with an antiseptic. The advantage of wooden lintels over windows in a house made of aerated concrete is the ability to build them yourself. Also, one cannot fail to note their heat-retaining properties, low cost, and light weight. When influenced external factors, they, unfortunately, become deformed and rot. Exposure external influences and short service life, in comparison with other types of crossbars, are their main disadvantages.

Metal profiles

They have excellent load-bearing characteristics, but their use is not always justified. The fact is that they are prone to metal corrosion. Yes, and the thermal conductivity of such products is very high, so there is a need additional insulation. However, before making steel lintels over the windows in a house made of aerated concrete, you should take into account some nuances:

• Before laying, it is advisable to cover the corners with paint on all sides;
• for fixation, the profiles are fastened with a wire tie or welding;
• the corners do not protrude from the wall, they are mounted in aerated concrete;
• Before installation, the corners are wrapped plaster mesh to ensure adhesion with plaster.

Made from monolithic concrete

This method of creating a concrete lintel on aerated concrete is the cheapest, but requires a lot of trouble. The result is a fairly strong structure that can withstand heavy loads. The disadvantages include the fact that after its installation, the uniformity of the wall surface is lost, which is revealed when a thin layer of plaster is applied. Before starting work on the installation of a monolithic beam, it is necessary to build removable formwork made of plywood, boards or other similar material.

When choosing material for lintels, the following characteristics are taken into account: the height of the building, its area, the weight of the walls, roof, ceilings (attic or between floors). It is also advisable to pay attention to the cost of the material and the desired time frame for the construction of the building.

For the reliability of the entire structure, it is very important to correctly calculate such parameters as the support area, the length and width of the reinforcing products. These components are determined based on the width of the window opening, as well as the height of the masonry above it. The depth of support of the jumpers on aerated concrete wall or the minimum length of the establishment in the masonry is determined depending on their type. The most popular options are:

The option without jumpers is also used in practice. To implement this plan, several requirements must be met:

1. The width of the window opening does not exceed 120 cm.
2. The height of the masonry above the frame is no more than 2/3 of the width of the opening.
3. Temporary formwork is being installed.
4. Reinforcement of several rows is carried out above the strengthening.
5. The voids are filled with aerated concrete adhesive.

Installation

Having become familiar with what lintels for aerated concrete are and the depth of support, let’s move on to the direct process of their installation.

Sequence of actions when installing aerated concrete U-blocks

Such beams are the most common in Lately, since the process of laying a finished factory product is quite simple. In addition, craftsmen manage to maintain the continuity of the masonry, while obtaining a perfectly flat surface. The technology is used to strengthen openings up to three meters, the work is as follows:

When can construction continue? Only after the structure has completely hardened do we continue construction. The timing depends on what time of year the construction is taking place, weather conditions, temperature and humidity. In hot, dry weather, concrete needs to be watered until it is completely set.

Stages of work when reinforcing an opening with a monolithic concrete product

Fill concrete mixture is, as already mentioned, the cheapest way to arrange a future window. Follow the step-by-step instructions:

Installation of jumpers from corners

Experts advise using metal corners to reinforce window designs up to 1.2 meters if the height of the subsequent masonry is at least two-thirds of the width of the opening. If this requirement is met, we proceed as follows:

1. We cut out the grooves for the corners with an indentation from the edges of approximately 10-13 cm.
2. Processing metal structure anti-corrosion compound, wrap it with plaster mesh.
3. Make sure that the product rests on the walls.
4. We lay the corners on the inside and outside.

Along with this method, reinforcement is also successfully used to strengthen narrow openings. The use of aerated concrete or reinforced concrete beams in these cases is not justified. To reinforce one opening, four rods with a diameter of 10 mm are used. The rods are placed in the holes, which are then filled with glue or mortar. Blocks are then laid on the fixed rods.

Strengthening the opening is a process that requires certain knowledge and skills. To ensure the reliability and durability of the structure, it is important to correctly perform the calculations and consistently carry out the described actions.

Strengthening foam concrete walls is a serious and thorough task in every sense. The point is that the types cellular concrete, foam concrete and aerated concrete, with all their technical and operational advantages, are highly hygroscopic. That is, walls, both indoor and aerated concrete, will inevitably absorb from environment moisture, and this is fraught with their rapid wear, fragility and cracks.

Reinforcement of walls made of foam blocks adds strength to the structure.

High humidity can also have an impact Negative influence on the microclimate in the apartment, lead to the appearance of damp and mold stains on the walls. However, these and many other problems can be avoided if you strengthen the walls in advance.

Material selection

Exterior wall finishing made of foam blocks: blocks, insulation, plaster.

So that the hard work of strengthening the walls does not go in vain, the first thing you should pay close attention to is the quality of the foam blocks themselves. Walls made of high-quality material will serve well for many decades, while low-quality foam concrete will begin to collapse within a couple of years. Therefore, you should purchase foam blocks from trusted manufacturers, having previously read the hygiene certificates and test reports. The foam block should be gray, but not white, slightly rough to the touch, dense, without cracks or chips. It should also be remembered that after release the foam block must rest for at least 28-30 days. During this time, it gains the necessary strength. A foam block that has not “ripened” to the required condition is very similar in properties to unfired brick and crumbles easily.

It should be strengthened during the construction stage. This is achieved by properly reinforcing the masonry and pouring a concrete armored belt 10-20 cm high under the floors, sufficient to support the weight of the floor slabs.

The blocks are reinforced every three to four rows using masonry welded mesh, which is a guaranteed way to increase the strength of foam concrete walls. Since the diameter of the masonry mesh is 4-5 mm, grooves are cut out for it in the masonry. They are made with a wall chaser, circular saw or a grinder, since foam concrete is easy to process.

Upon completion of construction, there are two ways to further strengthen the walls made of foam blocks: plastering with reinforced mesh or covering them frame materials, for example, drywall.

Reinforcement and plaster

Before applying plaster, foam concrete walls are treated with two layers of primer deep penetration with hydrophobic, that is, water-repellent properties.

After the primer has dried, the foam concrete wall is reinforced with an all-metal or fiberglass mesh. Optimal size mesh cells - 25x25 mm. It is attached to dowels, which are installed in such a way that the mesh between them is tensioned and fits tightly, without gaps, to the wall. Then, if necessary, beacon profiles are installed on top of the mesh. Work using reinforced mesh is a little more expensive, but the mesh greatly facilitates the plastering process itself, and also serves the main purpose - strengthening foam concrete walls.

If you plan to plaster a small area, you can do without reinforcing mesh. Just make a series of frequent, neat notches on the wall. Since foam concrete is a rather soft material, notches can be made with a regular hacksaw. However, this is only true for cut foam blocks. If the foam block is not cut, but cast, mesh reinforcement, even in small areas, is not only desirable, but necessary, due to the extremely low adhesion of this material. That is why, before starting work, a smooth block of cast foam concrete must be carefully processed with sandpaper or a file in order to give the surface the necessary roughness and increase its binding ability.

After installing the mesh and beacons, it is treated with a special gypsum, moisture-resistant, vapor-permeable plaster. It is better to take a ready-made dry mixture specially designed for surfaces made of. It is simply diluted with water and is easy to apply. You can make the necessary mixture with your own hands: 3 parts sand, 1 part cement, 1 part lime, 0.6 parts chalk. After applying the plaster, the wall must be puttied.

Walls made of foam blocks are painted with water-based silicate and silicone paints, which additionally cover shallow, up to 2 mm, cracks and, thanks to antiseptic additives, prevent the appearance of bacteria and microorganisms.

Aerated concrete walls are less durable than brick walls.

Installation front door aerated concrete has some features. Aerated concrete has lower strength indicators than brick or concrete, which must be taken into account in the process installation work. Otherwise service life doors may turn out to be less durable than we would like.

Installation of a standard size entrance door

If you are installing wooden door, the width of which is not more than 91 cm, then installation is carried out according to standard technology. That is, with fastening using metal anchors or plastic dowels with long self-tapping screws.

To do this you will need these tools:

• drill;
• screwdriver;
• plumb line;
• building level;
• hammer;
• welding machine with electrodes.

Here is the algorithm of the operations performed.

1. The ends of the opening are cleaned of dirt and dust.
2. A door frame is installed in it, from which it was previously removed door leaf. The location of the box is in the middle of the opening, while wedges are installed under it and on the sides for temporary support.
3. The box is strictly aligned in planes, for which a plumb line and level are used. First of all, the timber on which the hinges are attached is placed.
4. Through holes are drilled through the side vertical beam, while holes are made in the aerated concrete at the ends of the doorway. That is, this is a one-time operation. If you are not sure that you can do everything accurately and correctly, you can first prepare the holes in the box before installing it in the doorway, and then make holes in the wall through them. The depth of the hole in the wall is 8– 10 cm, distance between fastenings– no more than 60 cm.
5. Aerated concrete anchors are installed in the resulting holes (they are driven in with a hammer), with which the box is secured (screwed in with a screwdriver).
6. The door leaf is hung on hinges.
7. The gap between the frame and the ends of the opening is filled polyurethane foam. Until the foam becomes hard, the door must be kept closed.

Installation of heavy doors in aerated concrete

Installation metal door in aerated concrete requires a special approach to carrying out installation process. More complex fastening units are required here. The whole point is that the attachment points door frame are exposed to large and frequent shock loads. It is in this place that aerated concrete begins to crumble, so it is necessary to reduce these loads by distributing them evenly along the plane of the ends of the opening, and also to increase the contact area between the box and the ends.

To do this, you can install it around the perimeter of the opening wooden beam, which forms an additional box, or install wooden mortgages. Please note that everything additional elements must be dry and treated with antiseptics. It is believed that the first option with installing timber is optimal solution. It does not have to be installed along the entire perimeter: two vertical elements will be enough. It is very important that both elements are accurately aligned in the same plane.

There are several more requirements that determine the quality of the final result.

• The timber is fastened to the ends of the aerated concrete opening using aerated concrete or tile adhesive adhesive composition. It is important here that there is no gap between the two planes.
• Additional fastening is anchors or self-tapping screws for dowels. As for self-tapping screws, their length should not be less than 7.5 mm.
• You can use sections of it rather than a solid beam, installing them so that the distance between the fasteners is 61 cm. After installing the front door in aerated concrete, the gaps are filled with foam.

If heavy metal doors are being installed, the fastening should be carried out using an adhesive composition. The hole in the aerated concrete must be at least 15 cm deep. A pin or anchor is inserted into it, the threads of which are lubricated with epoxy glue. Please note that using aerated concrete adhesive for these purposes is not recommended. It has a runny consistency so it will pour out mounting hole when tightening the fastener. It is to these parts that the wooden frame of the opening in the aerated concrete wall is attached. And already to her– or the frame of a metal door, or the hinges of the door itself. Everything will depend on the thickness and width of the installed beams.

Some craftsmen use the technology of installing a metal door in aerated concrete, which leads to rapid failure of the fasteners. They make holes in the ends of the opening into which metal pins, usually made from reinforcement, are driven. After which the edge protruding from the door frame is welded to inside this frame. This is a grave mistake, because the reinforcement hammered into aerated concrete does not sit in porous material durable. This is the first. Secondly, holes are not always pre-drilled. The reinforcement is brazenly driven into aerated concrete, where the material is crushed. When subjected to heavy loads, the reinforcement begins to move, that is, backlash is formed. Literally two– three months of such operation will lead to cracking of the aerated concrete and the door falling out of the installation site.

Most perfect option installing a metal door in aerated concrete is the installation of metal embedded parts in the opening during the construction of the wall. The embed itself consists of two or three reinforcements located in the same plane, which are welded to a steel plate. Welding is performed perpendicular to the plane of the plate. Grooves are made in aerated concrete into which pieces of reinforcement are installed, all of which is filled with epoxy or aerated concrete adhesive. Then the top block is laid on top. The plate remains on the plane of the end of the doorway. There should be several such plates vertically, the distance between the reinforcement vertically– 61 cm. It is to the mortgages that the metal door frame is welded.

Adjusting the door leaf

After installing the door frame in the opening, you need to hang the door leaf on the hinges. It would seem that this is not the most complicated process, but there are several nuances to it. Especially when it comes to a metal door.

• It is necessary to throw a ball into the cavity of the lower loop (possibly from a bearing).
• The hinges themselves are cleaned and lubricated with any technical oil, but it is better to use graphite lubricant.
• Then the canvas is hung and closed.

• It is the closing that will show whether it is installed correctly and whether it is touching the box. If this is detected, then the door will have to be adjusted.

There are many various designs loops, but the bulk of them are adjusted according to the principle of a screw, which controls the installation location of the ball. To do this, you first need to determine which edge of the canvas touches the box. It is from his side that the loops need to be adjusted.

• First you need to unscrew the locking screw located perpendicular to the hinges (usually it is located on the bottom of the hinge).
• Then the clamping screw, which is located in the lower element at the lower end, relaxes. It is he who props up the ball.
• It is necessary to move the canvas from side to side and find a place so that it does not touch the box.
• Tighten the clamping screw.
• Screw in the locking element.

As you can see, installing doors in aerated concrete is not the most difficult task, but it does require knowledge of some installation nuances. Particular attention should be paid to the fastening points, on which the long-term and trouble-free operation of the door depends.

Often during the renovation process it is necessary to install partitions, and aerated concrete (gas silicate) is increasingly used for this. It is lightweight - it weighs several times less than brick, and the walls fold quickly. Therefore, aerated concrete partitions are installed in apartments and houses, regardless of what the load-bearing walls are made of.

Thickness of aerated concrete partitions

For the construction of partitions indoors, special gas silicate blocks, having a smaller thickness. Standard thickness partition blocks 100-150 mm. You can find non-standard ones in 75 mm and 175 mm. The width and height remain standard:

• width 600 mm and 625 mm;
• height 200 mm, 250 mm, 300 mm.

The grade of aerated concrete blocks must be at least D 400. This is the minimum density that can be used for the construction of partitions up to 3 meters high. Optimal - D500. You can also take denser ones - grade D 600, but their cost will be higher, but they have better load-bearing capacity: you can hang objects on the wall using special anchors.

Without experience, it is almost impossible to determine the brand of aerated concrete. You can “by eye” see the difference in density between the thermal insulation blocks. D300 and wall D600, but between 500 and 600 it’s difficult to catch.

The lower the density, the larger the “bubbles”

The only one affordable way control - weighing. Data on the dimensions, volume and weight of partition blocks made of aerated concrete are given in the table.

The thickness of aerated concrete partitions is selected based on several factors. The first is whether it is a load-bearing wall or not. If the wall is load-bearing, in an amicable way, a load-bearing capacity calculation is required. In reality, they are made the same width as the external load-bearing walls. Basically - from wall blocks 200 mm wide with reinforcement in 3-4 rows, like external walls. If the partition is not load-bearing, use the second parameter: height.

• For heights up to 3 meters, blocks 100 mm wide are used;
• from 3 m to 5 m - the block thickness is already taken to be 200 mm.

You can more accurately select the thickness of the block using the table. It takes into account such factors as the presence of a connection with the upper ceiling and the length of the partition.

Device and features

If aerated concrete partitions are installed during renovation of houses, markings must first be applied. The line is upholstered around the entire perimeter: on the floor, ceiling, walls. The easiest way to do this is with a laser plane builder. If it doesn't exist, it's better to start with a stream:

• Mark a line on the ceiling (two points on opposite walls). A painting cord, painted with blue or some other dry dye, is pulled between them. With its help they beat off the line.
• The lines on the ceiling are transferred with a plumb line to the floor.
• Then the lines on the floor and ceiling are connected by drawing vertical lines along the walls. If everything is done correctly, they should be strictly vertical.

The next step in constructing aerated concrete partitions is waterproofing the base. The floor is cleaned of debris and dust, a waterproofing layer is laid roll material(any: film, roofing felt, waterproofing, etc.) or coated with bitumen mastics.

Vibration dampening strips

To reduce the possibility of mother-in-law formation and increase sound insulation characteristics, a vibration-absorbing strip is laid on top. These are materials with many small air bubbles:

• hard mineral wool - mineral wool cardboard;
• expanded polystyrene high density, but of small thickness;
• soft fiberboard.

On short spans - up to 3 meters - no reinforcement is done at all. On longer ones, a reinforcing polymer mesh, a perforated metal strip, as in the photo, etc. are laid.

Connecting to a wall

To ensure connection with adjacent walls at the masonry stage, flexible connections are placed in the seams - these are thin metal perforated plates or T-shaped anchors. They are installed in every 3rd row.

If a gas silicate partition is installed in a building where such connections are not provided, they can be fixed to the wall by bending them in the shape of the letter “L”, inserting one part into the seam.

When using anchors, the connection with the wall is rigid, which in this case is not very good: a rigid rod due to vibrations (wind, for example) can destroy the adjacent adhesive and the body of the block. As a result, the abutment strength will be zero. When using flexible connections, all these phenomena will not affect the blocks so much. As a result, the bond strength will be higher.

To prevent the formation of cracks in the corners, between the wall and the partition, a damper joint is made. This can be thin polystyrene foam, mineral wool, a special damper tape that is used when laying heated floors, and other materials. To prevent moisture from escaping through these seams, they are treated with steam after laying. Not permeable sealant.

Openings in gas silicate partitions

Since the partitions are not load-bearing, the load will not be transferred to them. Therefore, there is no need to lay standard reinforced concrete beams or make a full-fledged lintel, as in load-bearing walls. For a standard doorway of 60-80 cm, you can lay two corners that will serve as a support for the overlying blocks. Another thing is that the corner should protrude 30-50 cm beyond the opening. If the opening is wider, a channel may be required.

In the photo to strengthen the opening standard door two were used metal corner(on the right), a channel is walled up in the opening on the left, for which grooves are selected in the blocks.

If the opening is not wide, and only two blocks are joined in it, it is advisable to select them so that the seam is almost in the middle of the opening. This will give you a more stable opening. Although, when laying on corners or channels, this is not the table: the load-bearing capacity is more than enough.

To prevent the metal from bending while the glue dries, the openings are reinforced. In narrow openings, it is enough to nail boards; in wide openings, a supporting structure resting on the floor may be required (put a column of blocks under the middle of the opening).

Another option for how to strengthen a doorway in aerated concrete partitions is to make a reinforced tape from reinforcement and glue/mortar. A flat board is stuffed strictly horizontally into the opening, nailing it to the walls. Sidewalls are nailed/screwed to the sides to hold the solution.

The solution is placed on top of the board, and three bars of class A-III reinforcement with a diameter of 12 mm are placed in it. Put on top partition blocks, as usual, keeping an eye on the movement of the seams. The formwork is removed after 3-4 days, when the cement “sets.”

Last row - adjacent to the ceiling

Since floor slabs can bend under load, the height of the partition is calculated so that it does not reach the floor by 20 mm. If necessary, the blocks of the upper row are sawn. The resulting compensation gap can be sealed with damping material: the same mineral wool cardboard, for example. With this option, sounds from top floor. More easy option— moisten the seam with water and fill it with polyurethane foam.

Soundproofing of aerated concrete

Although sellers of gas silicate blocks talk about high rates In terms of soundproofing, they greatly exaggerate. Even a standard block 200 mm thick conducts sounds and noise well, and thinner partition blocks even more so.

According to standards, the sound resistance of partitions should not be lower than 43 dB, and it is better if it is higher than 50 dB. This will provide you with silence.

To get an idea of ​​how “noisy” gas silicate blocks are, we present a table with standard indicators of sound resistance of blocks of different densities and different thicknesses.

As you can see with the block, at 100mm thick it falls slightly short of the lowest requirement. Therefore, at , you can increase the thickness of the finishing layer in order to “reach” the standard. If normal sound insulation is required, the walls are additionally sheathed mineral wool. This material is not soundproofing, but it reduces noise by approximately 50%. As a result, sounds are almost inaudible. The best indicators have specialized soundproofing materials, but when choosing them, you need to look at the vapor permeability characteristics so as not to trap moisture inside the gas silicate.

If you need absolutely “quiet” walls, experts advise installing two thin partitions with a distance of 60–90 mm, which should be filled with sound-absorbing material.

The house was built from aerated concrete. An armored belt was not installed during construction. Floor beams 1 and attic floor rest on a gas block. Cracks appeared in the partitions and above the window main wall. What should I do and is it dangerous to leave it like this? Dmitriy

Hello Dmitry!

The appearance of cracks is a sign of uneven deformations of building structures. Let's look at the cases in which cracks form in the walls.

1. Uneven deformations of the building base. May occur in problematic soils due to various kinds inclusions at the base of the building ( construction garbage under one of the corners of the building, manifestation of subsidence properties under the condition of leakage of water-carrying communications, etc.). Another one possible reason- uneven frost heaving of the soil, especially often affecting private houses of asymmetrical shape with basements without heating and insulation.
2. Insufficient load bearing capacity individual designs, incorrect Constructive decisions, violation of the rules (technology) for the construction of a structure.
3. Undermining the foundation.
4. Insufficient foundation depth (above UPG) when heaving soils.
5. Incorrect foundation type selected. Soil studies have not been carried out. Weak bearing capacity of soils (quicksand, peat).
6. Absence or defective waterproofing between walls and foundation.
7. If the walls are covered with multiple small cracks, sure enough they are plastered. Moreover, the plaster was done too quickly, before the blocks had dried, and with a material with low vapor permeability.

The result of haste and the use of inappropriate plaster. The raw block was quickly laid and quickly plastered with a mixture of low vapor permeability

Without determining the causes of cracks and based on the amount of information provided, it is not possible to create a list of necessary measures. You should call a specialist (foreman or design engineer from design organization) with experience in strengthening structures. Provide him with as much information as possible, namely:

Ground water level. If you don’t know it, tell us whether water appeared in the trenches when pouring the foundations, whether there is seasonal flooding in the spring, whether there is water in the neighbors’ basements (or yours, if you have one).
1. Compressive strength (in everyday life - strength grade) of aerated concrete blocks, what composition (mortar) they were laid on. The pitch and dimensions of the floor beams, rafters, what the lintels over door and window openings are made of, what the deformed partitions stand on (on their foundation or simply on the floor).
2. Construction of floors, ceilings and roofs.
3. Report on engineering and geological surveys.
4. It is necessary to inspect on site the efficiency of drainage from the building (integrity, angle of inclination and width of the blind area).
5. If the house is plastered, then with what mixture and how long after the walls were built.
6. How long did it take from purchasing the blocks to installing the walls? Under what conditions were they stored?

Based on these data and the results of a field survey, the specialist must create a list of measures to strengthen structures. Unfortunately, there is no information about lintels over openings. The presence or absence of finishing of the house inside/outside can have a significant impact.

The general principle of strengthening unreinforced walls made of aerated concrete blocks with a reliable foundation and access to the wall surfaces is as follows:

Let us emphasize once again that the above list is no more than an indicative recommendation. Without a full-scale inspection of the building, it is impossible to make a final decision. Moreover, some types of strengthening work may require the installation of temporary supports for floors, etc. Carrying out reinforcement work on your own without consulting a specialist who has directly examined your home is dangerous.

If the house stood for quite a long time (at least a year), and only then cracks appeared, small ones at that, you can try to limit yourself to installing gypsum beacons on the cracks themselves. They should be examined once a week for the first month, then once a month for a year. If cracks appear on the beacons, it means that deformation continues and a call to a specialist cannot be avoided.

A cracked lighthouse is a sign of increasing deformation