Engineers’ Syndicate Recommends Amending Building Code after Earthquake

The Syrian Arab Code Committee in the Syrian Engineers’ Syndicate recently issued its recommendations regarding developing a code for constructing earthquake-resistant concrete buildings. This was based on a study of the causes and consequences of the earthquake on February 6, 2023.

The Syrian Arab Code for the design and implementation of reinforced concrete structures is an urban construction system for designing and implementing buildings to achieve acceptable safety in construction. Engineers and building contractors must apply this code in their design studies when seeking construction permits. The Engineers’ Syndicate and administrative units oversee compliance with the code during various construction phases.

Syria’s prime minister formed joint committees in the four governorates most affected by the February 6 earthquake, Aleppo, Lattakia, Idlib and Hama, to assess the conditions of collapsed and damaged buildings. These committees, known as the Quintuple Committees, consisted of five members each: the head of the General Company for Engineering Studies (GCES) branch, the head of the Studies Department in the Technical Services Directorate, a representative from the Engineers’ Syndicate, a university representative, and a representative from the Contractors’ Syndicate. These committees visited the sites of damaged buildings, reviewed their structural studies, and conducted tests on the resistance of concrete and reinforcement steel and soil properties at the sites. They prepared extensive reports outlining the causes of collapses and cracks.

The reports indicated that the damaged buildings were not designed or executed according to the building code, with most collapses and cracks due to poor implementation and lack of soil tests. However, this conclusion is inaccurate, as many of the buildings designed and executed according to the Syrian code for construction collapsed, especially in the city of Lattakia.

Based on these reports, the Syrian Arab Code Committee met and issued its latest report, which the Council of the Engineers Syndicate ratified. Although the Code Committee affirmed that the current code requirements were sufficient to resist earthquakes, it decided to continue developing the code and its appendices. This decision came in response to what the committee described as directives from the Council of Ministers on the necessity of code development in coordination with the National Center for Earthquakes to update Syria’s seismic maps, making the code compliant with the latest global expertise.

However, the recommendations of the Code Committee implicitly acknowledge shortcomings in the code regarding soil mechanics, reinforced concrete, foundations, shear walls, and reinforced steel. Among these, the recommendations emphasize the necessity of conducting at least two soil tests at the construction site after excavation: the first at a depth of no less than five meters below the basement level to determine the soil type and the second at a depth ranging from 15 to 30 meters below the foundation level to determine the required foundation depth unless a rock layer is reached at a depth of five meters across the entire site.

The recommendations also include increasing the cross-section of reinforcement steel bars and the required quantity of reinforcement steel in concrete buildings. Every building taller than five storeys should consist of a shear wall in each direction, with symmetry maintained wherever possible. A shear wall is a load-bearing wall made of reinforced concrete built to the full height of the building.

The recommendations stipulate that no additional storeys be allowed on any existing building unless the building was originally designed to accommodate the extra height as per its granted permit. Even in this case, the administrative unit and the Engineers’ Syndicate must issue a structural, technical report proving that the building’s condition can withstand the additional storeys. It is important to note that property owners can modify the construction permit and increase the number of storeys if an engineering structural report confirms that the building’s foundations could bear the required additional weight, with the approval of the relevant municipal departments.

The recommendations emphasise the need to intensify tests conducted on high-strength reinforcement steel used in construction and prohibit cladding any building before issuing a technical report confirming its structural safety. This is partly a consequence of the impact of the lengthy duration of many construction projects and the long time gaps between construction and cladding phases. which weaken the buildings’ earthquake resistance. Construction can span decades, particularly for public sector projects, which lead the concrete structure of the built unit to remain exposed and unprotected from the weather for long periods.

The Code Committee also referred to a set of issues that were discussed in its meetings but have not yet been decided upon. Among these issues are studying seismic maps through a joint committee from the Syndicate, the Atomic Energy Commission of Syria, the Higher Institute for Earthquakes, and the National Center for Earthquakes, to review and develop the current seismic maps in coordination with the Syrian Arab Code Committee.

Additionally, there is a focus on securing and using seismic measurement devices and expanding their usage to include the study of most construction sites. This also involves expediting the soil classification for various sites and securing equipment that assists in this process, to use the results in designing earthquake-resistant buildings. The report proposed to form a committee in each branch to review soil reports.

It also emphasises the importance of meticulous study and quality control through highly qualified engineering supervision, achieving the technical specifications of the used materials, increasing the stages of review during the project, and prohibiting the construction of additional storeys before ensuring the quality of the structural elements in the lower storeys, both in terms of steel and concrete.

There is a stress on the necessity of certifying any new building by a qualified technical committee, and this committee should verify the correctness of the implementation and conduct some possible tests. Solutions need to be found for addressing violations, narrow streets, and construction on geological faults and agricultural lands, as they are extremely dangerous and prone to collapse in the event of an earthquake.

Notably, the committee asked the Syndicate’s Council to issue a circular to prevent the use of recycled and locally manufactured reinforcement bars that do not meet the code requirements. These bars are made from iron pulled from debris, re-melted, reshaped and sold in the local market.

These observations implicitly indicate the existence of shortcomings in the code’s implementation procedures. The seismic maps are not accurate, as pointed out by many engineers who spoke with The Syria Report after the earthquake, and there is a lack of precise seismic measurement devices. The committee acknowledges the existence of shortcomings in the review of structural studies and the follow-up of the reviewers’ recommendations, in addition to the inaccurate execution of structural studies and deficiencies in the inspection, evaluation and testing procedures before and during the project implementation.