Why brickwork is 10 times less durable than brick: we consider the reasons

The brick has a high compressive strength and this strength is six times higher than that of aerated concrete block! But oddly enough, a wall made of ordinary brick and a wall made of aerated concrete are approximately equal in strength. What is the reason? Let's figure it out!

Brick through the eyes of the layman

Brick is undoubtedly a strong material. Its strength characteristics are several times higher than those of light aerated concrete, and this is a fact. And also brick is famous for its durability, environmental friendliness and low cost. The durability can be judged by the ancient buildings made of this excellent building material. Its aesthetic qualities should not be overlooked - brick buildings really look attractive. One conclusion suggests itself: a brick must be taken and built only from it.

A bit of reasoning on the topic

But we are used to considering brick as a separate element. Yes, indeed, it has outstanding characteristics, but, as always, there is one but: the brick is part of the wall, and the wall is already a separate system. And in this system, in addition to the above-mentioned bricks, there are: mortar; and, oddly enough, the quality of the work. And it is these factors that negate the individual characteristics of the brick.

What affects the strength of the masonry?

To analyze this issue, you first need to look at the "Manual for the design of stone and reinforced stone structures." There in paragraph 3.4 it is indicated in black and white.

The following factors act on masonry subjected to compressive forces:

• brick strength;
• the size and geometry of the brick (correctness of the shape);
• the number of voids in the hollow brick;
• masonry mortar and its strength;
• workability of the solution (mobility);
• deformability of the frozen solution;
• quality of masonry work;
• bandaging the masonry;
• adhesion of the solution to the stone surface;
• the degree of filling of the vertical seams.

And also a considerable influence on the final strength of the wall gives the stone resistance to bending and tensile forces. Paragraph 3.7 says: the adhesion of the mortar to the stone and the quality of filling the vertical joints affect the compressive strength of the masonry. The solidity of the masonry, its resistance to cracks, the resistance to bending and stretching in case of uneven settlement of foundations significantly depend on the above factors.

Here you should pay special attention to the phrase: solidity of the masonry. If it's simple, then there should be no unfilled joints, voids, nests and other things in the wall. Does the bricklayer take care of this when working?

Conclusion: the compressive strength of the masonry when a stress moment occurs in it is much less than the same parameter for a single element of the masonry - brick.

There are many factors and here the expression comes to mind about like a snack the degree steals. And if you disassemble each reason separately, it turns out that the wall eventually loses most of its strength precisely because of the mortar and the quality of the masonry.

Where the dog is buried

The first factor is the use of high-quality masonry mortars. Many believe that the use of ultra-strong mortars for the construction of the wall will improve the quality of the masonry. The adhesion of the mortar to the stone directly depends on the presence of a binder in its composition - the more cement, the less adhesion. This is due to the fact that when dry, the solution shrinks, changes in size; the size of the brick remains unchanged. At the same time, the adhesion of the solution and the stone is lost due to the movement of the solution. This is called shrinkage cracks and because of these cracks, the wall is eventually blown through. There is one rule - the stronger the mortar, the less deformability of the masonry and the higher its fragility. Therefore, the lower the grade of the solution, the less shrinkage. It is best to add lime to the composition of masonry mortars and reduce the amount of cement.

The second factor is that quality construction by standards takes time and costs money. Now everyone is chasing the number of laid out cubes and built houses, which significantly affects the strength characteristics of buildings. If you resort to the above manual, in paragraph 3.7 you can see that there is even such a thing as vibrating brickwork to better compact the mortar. Vibration increases the strength of the masonry by 1.5-2 times - this is how the best quality is achieved. And who will fill the seams with such zeal? 50% of bricklayers will not work on a whim.

What's the bottom line?

Theoretically, high-strength brick and strong mortar should give an appropriate result. But this is the case when plus and plus gives a minus. You need to adhere to the rules and maintain a balance between stone and mortar.

Designers are aware of the whole situation with the quality of the masonry and make calculations taking into account the reduction factors. For engineers, the average clutch is called: industry average. That is, in the end, with all the errors, the strength of the masonry loses up to 90% from the strength of its main element - brick.

Popular dispute - brick or aerated concrete

Supporters of aerated concrete use the weakness of masonry to prove that their houses are not inferior in strength to brick ones - they are partly right. And if you look at it, you can understand why aerated concrete is a technological material. It's about the geometry and the large format of the block. Smooth geometry and large size reduce the amount of masonry mortar. That is, the compressive strength of a block and a wall made of aerated concrete blocks remains practically unchanged, while the brickwork loses all the original strength of the stone.

Do you choose aerated concrete or brick? Write in the comments!

There are already more than 30 thousand of us! Subscribe to our channel, like, share the publication - we are working, so that you receive only useful and relevant information!

Read also:

• How to legalize unauthorized buildings.
• What can be done from an old gas cylinder or disk: a selection of atypical barbecues.

Watch the video - Attic layout: ideas and constructive advice.