The important (and critical) role of the construction industry in preparing for earthquakes
Jun 30, 2022
By: Itzick Simon
A strong earthquake in Israel is not a question of " when? " but of " how much?" That is, How much damage will the earthquake cause and how many physical injuries will it leave behind (read more about the history of earthquakes in Israel here).
In the following short article, we will discuss the critical role the construction industry plays in dealing with earthquakes. We will discuss the steps that have been taken, analyze their effectiveness, and take a brief look at the future.
By: Itzick Simon
A strong earthquake in Israel is not a question of " when? " but of " how much?" That is, How much damage will the earthquake cause and how many physical injuries will it leave behind (read more about the history of earthquakes in Israel here).
In the following short article, we will discuss the critical role the construction industry plays in dealing with earthquakes. We will discuss the steps that have been taken, analyze their effectiveness, and take a brief look at the future.
Meet Israeli Standard 413
Awareness of the dangers facing millions of Israelis from earthquakes began to gain momentum in the late 1970s, in a process that led to the formulation of one of the most important standards in the local construction industry, the "Israeli Standard for the Resistance of Buildings to Earthquakes," known for short as I.S. 413 .
The standard was published in 1975 and led to significant improvements . As evidenced by the fact that, starting in the early 1980s, a significant portion of buildings in Israel were actually built in accordance with the above standard with good resistance to strong earthquakes. According to the Planning and Building Regulations (Permit Application, Conditions and Fees), 1970, there is a requirement to implement the standard in new construction in Israel [1] .
It should be remembered that the standards of the standard guidelines are intended to save the lives of those present in the structure and its surroundings. They are not intended to prevent, in most structures, significant physical damage and the need for alternative housing and significant rehabilitation or reconstruction.
Although the number of buildings that are adequately resistant to earthquakes has increased, there is still a significant number of buildings in Israel that were not built prior to the directives of the Ministry of Defense and are in clear and immediate danger of collapse following earthquakes, as well as in extreme cases of very severe weathering or a direct threat of war.
המודעות לסכנות שרובצות לפתחם של מיליוני ישראלים מרעידת אדמה החלה לצבור תאוצה בסוף שנות ה-70 בתהליך שהוביל לניסוחו של אחד התקנים החשובים בענף הבנייה המקומי והוא "התקן הישראלי לעמידות מבנים ברעידות אדמה" הידוע בקיצור בתור ת"י 413.
התקן פורסם ב-1975 והוביל לשיפור ניכר. לראיה, החל מתחילת שנות ה-80 חלק משמעותי מהמבנים בישראל נבנה בפועל בהתאם לתקן הנ"ל עם עמידות טובה כנגד רעידות אדמה חזקה. על פי תקנון התכנון והבנייה (בקשה להיתר, תנאי ואגרות), תש"ל-1970, ישנה חובה לממש את התקן בבנייה חדשה בישראל[1].
יש לזכור שאמות המידה של הנחיות התקן נועדו להציל את חיי הנוכחים במבנה ובסביבתו. הם לא נועדו למנוע, במרבית המבנים, נזק פיסי משמעותי וצורך בדיור חלופי ובשיקום משמעותי או בינוי מחדש.
למרות שהיקף המבנים שעמידים ברמה נאותה לרעידות אדמה צמח, יש עדיין בישראל היקף לא מבוטל של מבנים שנבנו שלא לפני הוראותיו של ת"י ומצויים בסכנת התמוטטות ברורה ומיידית בעקבות רעידות אדמה, כמו גם במקרים קיצוניים של בלייה חמורה מאד או איום מלחמתי ישיר.
T.I. 413 has undergone updates over the years, and one of the most important of these was in 1995, as part of a move that tightened its requirements. For example, the criteria in the standard in the Tiberias area were increased by about 300% and expanded by about 200% for tall buildings in Tel Aviv [1] . Additional updates were made in 1998 and 2009.
Since the 1990s and following the Gulf War ( 1991 ), which illustrated and brought to the forefront the rocket and long-range missile threat, over the threat of aerial bombs dropped from aircraft, the Israeli concept of defense has also changed: from shelters to protected spaces.
The apartments began to be built with "apartment protected spaces" (APS) that are integrated into the building system and are made of reinforced concrete. The APS constitute a significant addition to the strength and rigidity of the structure, and their contribution will be noticeable in the event of an earthquake.
In parallel with developments in the engineering field, there has been progress in seismological capabilities in general and in seismic activity in the Land of Israel and its surroundings in particular. The knowledge gained has had an impact on the design of buildings in Israel against earthquakes, including the division into dangerous areas in terms of seismic intensity [2] .
[1] http://www.iame.org.il/uploadimages/tama%2038/TAMA38presentation.pdf
[2] https://www.mapi.gov.il/Earthquake/Pages/riskDavid.aspx
Important updates to the standard over the years
In 2005, the state decided to launch TAMA 38, or by its official name – "The National Outline Plan for Strengthening Existing Buildings Against Earthquakes."
The rationale behind TAMA 38 was to promote strengthening of buildings against earthquakes by collaborating with the homeowner public and the private market. This is done through an effective economic-licensing tool that creates a business-economic incentive that does not depend (only) on regulation and/or government budgets.
The apartment owners who apply for TAMA 38 allow the developer to renovate and expand the building in which they live, including their private apartments, and in return the state allows the construction of additional floors with new apartments. The entrepreneurial profit is the generator of the event. It embodies the economic viability of the project, while the tenants do not directly bear the cost of the renovation and expansion.
TAMA 38
In 2008, TAMA 38 underwent an update known as TAMA 38/2. It was determined that apartment owners could not only renovate but also completely demolish the building and build a new structure underneath it that meets the updated structural standards and requirements. TAMA 38/2 thus received the name (common in the public) – "TAMA 38 Evacuation-Construction."
The popularity of TAMA 38/2 has gained momentum in light of the potential it holds in terms of local renewal and an upgrade in the standard of living of apartment owners. Instead of an upgraded apartment in an old and reinforced building - a new apartment in a new building. The good news here is a solution for especially old buildings that were not worth investing in strengthening from an economic-engineering perspective. As of today, over 50% of construction projects in Israel according to TAMA 38 are being carried out within the framework of demolition and reconstruction (TAMA 38/2).
TAMA 38 , with its two alternatives, yielded impressive results but failed to provide a nationwide solution to the problem of the country's preparedness for earthquakes. One of the main obstacles to its progress is the limited entrepreneurial profit in peripheral areas where housing and land values are low to begin with.
" The main characteristic of TAMA 38 is its reliance on the economic viability of its implementation, which is determined by the value of the land, " reads a document by the Knesset Research and Information Institute published in January 2022 ("Description and Analysis of TAMA 38 and the Proposed Plan to Replace It"), " According to the State Comptroller's report from 2018, it was already known when TAMA 38 was formulated that it was not sufficient to ensure the reinforcement of buildings, and that, in parallel with its implementation, work should be done to formulate supplementary economic arrangements, including financing arrangements for the reinforcement of buildings in peripheral areas where it would be difficult to find financing for reinforcement due to low land values and lack of demand ."
TAMA 38/2
"Until the implementation of Israeli Standard 413 in its parts, buildings in Israel were designed primarily for vertical external loads on the structure from the outside inward, with an emphasis on gravitational forces. The impulsive, offensive load, created by an earthquake, is a load that acts horizontally on the lower part of the structure first, while gravitational forces act from top to bottom," says Dr. Benny Brosh, Director of the Building Division at the Standards Institute of Israel, a lecturer in structural engineering in the Department of Civil Engineering at Ariel University, and one of Israel's leading experts in the field of civil defense.
"The nature of Israeli construction that had been used until then included open, sprawling ground floors with a few columns and stiffening elements and with thin supporting elements. All of this is precisely in the lower area of the structure where the earthquake load is greatest and stems from the cumulative mass of all the floors above it."
Dr. Brosh adds that although TAMA 38 did not completely solve the problem, the criticism heard in the construction industry and in the relevant press about the plan is not a black and white matter.
"When I look at the glass half full, TAMA 38, when implemented properly, saved quite a few potential lives," says Dr. Brosh. "According to the official reports of the Government Authority for Urban Renewal, as of 2020, this involves approximately 1,300 buildings and approximately 26,800 apartments [1] ."
[1] https://www.gov.il/BlobFolder/reports/urban_renewal_report_2020/he/hithadshut_ironit_documents_urban_renewal_report_2020.pdf
TAMA 38 – Between criticism and the glass half full
Dr. Brosh lists several key barriers and challenges facing construction projects according to TAMA 38:
· Difficulty in obtaining tenants' consent to the project, and sometimes even due to tenant disputes or a desire to maximize building rights (and in some cases "legalizing building violations").
· Lack of economic viability if the entrepreneurial profit does not justify the project costs .
· Construction in a dense urban area without a real ability to provide all other required infrastructure, such as sewage infrastructure, municipal institutions, green lungs, transportation routes, etc. In other words, using existing infrastructure despite an increase in the load placed on it.
· The connection between the old and the new is always problematic and complex – both from an engineering and an operational perspective.
· In projects according to TAMA 38/1 – residents living on construction sites for a long time.
· Construction in a dense urban area with all the complexities involved, for example, in supplying building materials, bringing in heavy engineering tools, and safety problems for residents and passersby.
· Extreme inconvenience to residents during construction.
· Potential damage to local infrastructure, especially those buried in the ground.
Key barriers and challenges
Many in the construction industry and among decision-makers believe that the TAMA 38 plan has reached its limit and can no longer "deliver the goods." The general direction of the state today is to promote large -scale demolition and construction projects. In other words, urban renewal driven by the local authority and planned for entire complexes, down to streets and neighborhoods.
Dr. Brosh explains that this is a correct perception, but strongly warns that the conditions that exist today according to TAMA 38 should not be completely abolished and/or derogated from. This is because the existing plan is more suitable for the rapid and focused implementation of a single building (or adjacent buildings such as railway housing estates), and in particular in terms of licensing procedures.
"Of course, I am in favor of large projects and evacuation-construction is correct and effective," says Dr. Brosh, "However, at the same time, we must remember that there are places where we have no choice but to act according to the existing TAMA 38. Evacuation-construction is not appropriate in every urban space and blocking the specific solution may be irresponsible."
He adds that it is certainly possible to address the challenges of urban renewal in Israel not only at the level of legislation and standards, but also by promoting awareness and exposure.
"The state must work on public awareness and promote the importance of strengthening buildings and urban renewal in many ways with the public," says Dr. Brosh. "This also means reaching out to people through their pockets. I would suggest, for example, increasing public awareness regarding the increase in the value of apartments in terms of sale or rental after urban renewal and the gaps that arise between the upgraded properties and those that have not yet gone through the process."
"Another option is to take it in a security direction by emphasizing the simple message that a TAMA 38 project allows for the establishment of a fire protection system and the strengthening of the building as a whole against security incidents. If an earthquake still sounds like a somewhat 'distant' risk, despite the worrying data that we all know, a rocket threat is unfortunately much more tangible. Another avenue could be expressed in promoting the strengthening of buildings through insurance premiums."
The direction – evacuation and construction
Steps in the right direction?
לפני סיום נציין כי המדינה בהחלט מבינה שיש לענף הבנייה תפקיד מפתח בהתמודדות עם רעידות אדמה ובשנים האחרונות ננקטו לא מעט צעדים בנושא. למשל:
· הגדלה עקבית של התקציבים הממשלתיים להתחדשות עירונית במסגרת תקציב המדינה.
· קידום הסכמי מסגרת להתחדשות עירונית עם תמריצים כספיים לרשויות בעבור הוצאת היתרי בנייה.
· תמיכה ממשלתית בהתחדשות עירונית בפריפריה.
· תיקוני חקיקה הנוגעים לסוגיית כמו הסכמת דיירים והורדת רף "הרוב הדרוש".
· תיקוני רגולציה לגבי היטלי השבחה בהתחדשות עירונית.
· תיקוני חקיקה לשימור זכויות בעלי הדירות.
· הרחבה פעילות תכנון יזומה של הממשלה לסיוע בקידום פינוי בינוי במקום תמ"א 38 (במיוחד באזורים הנושקים לציר הרכבת ומערכת המטרו בגוש דן).
Before concluding, we would like to note that the state certainly understands that the construction industry has a key role in dealing with earthquakes, and in recent years quite a few steps have been taken on this issue. For example:
Consistent increase in government budgets for urban renewal within the framework of the state budget.
Promoting framework agreements for urban renewal with financial incentives for authorities for issuing building permits.
Government support for urban renewal in the periphery.
Legislative amendments concerning issues such as tenant consent and lowering the "required majority" threshold.
Regulatory amendments regarding improvement levies in urban renewal.
Legislative amendments to preserve the rights of apartment owners.
Expanding the government's proactive planning activity to assist in promoting the evacuation of construction in place of TAMA 38 (especially in areas adjacent to the railway axis and the metro system in the Dan Bloc).
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