It was not always built specifically. Years ago, other materials were used for housing construction. However, the search for builders was always to find a highly resistant material. Thus they found the concrete that today is one of the favorites.

Today we can see concrete as a structural part of different works, both in civil and industrial constructions. One of the most prominent properties of concrete is its resistance to understanding, but what does this mean, and how can you verify that the concrete is. In this post, we tell you more about it.

What is resistance to understanding?

It is the maximum effort that a material can withstand the crushing load. The resistance to understanding is measured, taking into account the maximum amount of effort that is necessary to deform a material. The formula for calculating the resistance to understanding is the division of the maximum load between the original transverse areas of ​​a test piece in an axial compression test.

How do you verify the resistance to understanding concrete?

The engineers of the work specified in the plans the resistance that the concrete is must-have. But in practice, this does not always follow these indications, and it is for which the information should be verified to ensure the quality of the material. This will ensure the safety of the structure.

There is a standard for verifying the strength of concrete, and it is the Standard for Reinforced Concrete E-060. According to the standard, this procedure is followed to measure the resistance to the understanding of a sample that will then be compared with what is indicated in the structural drawings of the work.

Why do a verification of resistance to understanding?

It is possible that the first years after the compression, the effects of a verification error are not noticed, but there will be future consequences on the structure. On the other hand, if the verification is done and this gives a positive result, it is guaranteed:

  • The good quality of concrete.
  • That the workmaster respects the indications of the plans.
  • The good behavior of the structures before seismic movements.

Can you use seawater?

You can only use seawater in the preparation of concrete if you have the authorization of the project engineer and supervision. You should not use it in the following cases:

  • Concrete reinforced and prestressed.
  • Concrete with resistances greater than 17 MPa at 28 days.
  • Concrete with embedded elements of galvanized iron or aluminum.
  • Concrete with a surface finish of importance.

You will not use in the curing of the concrete or in the washing of the equipment, those waters that do not meet the above requirements.

Mixing water for prestressed concrete or concrete containing embedded aluminum elements, including the part of the mixing water with which the free moisture from the aggregates contributes, must not contain harmful amounts of chloride ions.


A 41-year-old worker has died on Wednesday after falling through an elevator shaft along eight floors while working in a building under construction on the Gran Vía in Madrid. The accident has occurred inside the number 29 of this street, a building built in 1920 and where the Casa del Libro is located. They are the works of what will be a future hotel of the Cristiano Ronaldo chain.

Labor inspection sources told the Labor Commissions union that there was a network “but that it has yielded.” “This should not have happened if all the security measures had been taken. They are going to roll heads because the company will have to point to a person in charge. That elevator shaft had to have been fenced and was not,” said some of the fellow workers, an extreme that the consulted union representatives could not confirm. When there is an elevator shaft in a construction site, there must be security measures such as a net or a railing, explained Workers’ Commission members.

The unions will concentrate on Thursday in Cibeles and read a manifesto against workplace accidents, as they usually do when an accident of this type occurs. With this, there are already 53 people killed in occupational accidents in the region since January, according to CCOO. Twelve of them were produced in building construction works.

The notice was received shortly before 11.00 in the morning, according to Emergencies Comunidad de Madrid 112. The Summa has only been able to confirm the death of the victim, who suffered from trauma and died immediately after falling from the sixth floor to Minus two. The firefighters of the Madrid City Council have rescued the body.

The construction company responsible for the hotel is in charge of the San Martín Company that subcontracted the deceased carpenter. According to the workers present after the accident, the worker was moving a closet with other colleagues inside one of the rooms when he rushed into the void. According to the union, there will be a trial to determine if the company that placed the network that protected the elevator shaft did so following all the protocols or if, on the contrary, there was negligence.

More accidents in the construction

According to data released on Monday by the Community of Madrid, nine workers lost their lives in September in occupational accidents, five of them and the rest during the day, two of them due to falling in height, another due to a crash with an object and other due to a nontraumatic pathology.

Also, according to the regional government, between January and September, there were 68,897 occupational accidents, 82.6% during the working day, and the rest  which represent 1% less than in the same period of 2018. CCOO highlights the decrease in accidents throughout the year in almost all sectors of activity, except in the construction sector, which – he says – “continues to have a very negative behavior: total accidents have increased by 13.4%, and fatalities are they have doubled, which has meant the death of 6 more workers, going from 5 the year before to 11 in this year.”