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Haifa Chemicals South - industrial buildings and facilities Carrying out several construction and repair projects on the factory premises The challenge: A plant that includes many and varied construction elements in a variable soil section (sand/clay/lime bundles) and a very aggressive environment (chemicals) that damages the concrete. Repairing buildings and elements damaged by aggressiveness and damage to the ground. The solution: Collecting all the results of the field investigation from all over the plant enabled the use of existing knowledge and the reduction of field investigations in new projects. Adjusting the foundation solutions and performing aggressive soil tests in the various areas.

Soil anchors in Israel - vision and reality This article examines what is happening in the field of soil anchors about ten years after the issuance of the first Israeli standard in the field. The soil anchors have been used for many years in the construction industry to stabilize buildings, slop es, retaining walls, piers, dams, etc., and are designed to transfer forces from the front of the building to a stable area underground. Stability is achieved by significantly increasing the normal forces acting on potential destruction planes. Driving the anchors in advance for required labor may reduce the future displacements of the anchored structure. A choice of using soil anchor alternatives should take into account the advanced technology used in it to recruit relatively high workforces, while immediately checking the endurance both in the short term and in the long term. The article was published in the professional journal of the Association of Construction and Infrastructure Engineers "Construction and Infrastructure Engineering" Issue No. 90, March 2021. 1. The role of soil anchors and their importance in construction and infrastructure industries A. Ground anchors have been accepted in the construction and infrastructure industry in the world and in Israel for many years. The anchors are used in a wide variety of applications, such as: walled excavations for basements, in places where open excavations are not possible, due to considerations of space and risk to buildings and infrastructures, a means of protection against slope sliding, to receive the troubles expected from the planned construction such as dynamic forces caused by wind and earthquake disturbances, as well as lifting forces caused d ue to underground construction, below the groundwater level. Ha Lochem St. Bnei Brak. Sheathing walls on stilts are supported by anchors and soil nails B. The above speaks for itself and emphasizes the importance of the anchor component as complex and unusual construction elements. A review of the Israeli standards and general and special specifications reveals that these elements constitute a complex category, which includes a constructive aspect on the one hand, and a geotechnical aspect on the other. This aspect requires the action of construction planners skilled in the field with geotechnical consultants in the field of soil and foundation. C. Geotechnical structures are divided into three categories (as can be seen, in T.I., 940 part 1 and T.I. 940, part 3.1: geotechnical category No. 1, 2 and 3). According to this division, elements that include defined soil anchors, usually, as category 3. This means that failure of their function may cause serious damage to the nearby environment, disruption of the operation in the area, heavy economic damage, damage to people and property. Also, there is great difficulty in repairing and restoring the site and its surroundings, which requires a lot of time. D. It is clear that structures and anchored elements require special attention, both in the planning aspect and in the performance aspect. Failures in this area also create a negative media resonance. Over the years, many failures in this field have been published, as can be found for example on the Internet, which include, for example, the collapse of drywall walls in Ra'anana, Beit Shemesh, in a large project in Bnei Brak and many others known to those in the field. On the other hand, you can find impressive projects that have been successfully carried out (attempting to attach images from these sites is difficult to impossible due to copyright issues. Readers interested in this can find them by searching the Internet). E. Every year, about 20,000 anchors are installed in Israel, in many and varied projects. The majority of the anchors (about 95%) are temporary anchors, which are replaced during construction by permanent structural elements, such as ceilings. The rest (about 5%) are permanent anchors that are supposed to be used for the entire length of the structure, which in public projects reaches 120 sleep. F. Anchors are a complex mechanical element in its structure, in the way it is installed and in the way it functions and in the existing length of the structure. Failures in anchors can be due to the following reasons: Inadequate design of the support system, which includes the anchor + the constructive element it supports (conventional wall, reinforced concrete facade, bridge, etc.). An area under the responsibility of the planning team, mainly. Failure in the structure of the anchor itself, on its various components, which includes mechanical components, protections against corrosion, drilling and installation of the anchor. This area, for the most part, is the responsibility of the anchor contractor. Failure to test the anchor and guide it, including full monitoring of the anchor. The responsibility for this area is discussed in detail within this article. 2. The anchor, its components and standard requirements A. In 2011, a detailed Israeli standard was issued for the first time, dealing with ground anchors, TI 940 part 4.2, called "Geotechnical design: strengthening and stabilization of structures for engineering purposes - ground anchors made of piles". This standard is defined as a recommended standard, which is not legally binding (unless it is determined as such in another legal framework, which adopts it as binding). B. The anchors develop relatively high service tolerances for each anchor. This allows for a reduction in the number of anchors per square meter of wall façade and makes them more economical than other anchoring methods. This advantage is accompanied by a disadvantage, since the system has lower redundancy, due to which failure of a single anchor may create progressive failures in adjacent anchors, which may lead to a general failure. C. In light of the above and the complexity of the anchor, it is necessary to ensure that the requirements regarding the anchors are clear and include, among other things: Proven documentation of the various anchor components. The components of the anchor will be compatible with each other, in a way that guarantees the use of spare parts, without improvisation and meeting all the requirements. The properties of the materials will not change during the existing length of the anchors, (up to two years for temporary anchors and for the entire period of the structure's existence, for permanent anchors). The use of new technologies and methods is allowed if there is documentation, tests and knowledge proving the anchor's resistance to all standard requirements. Ha Lochem St. Bnei Brak. Sheathing walls with piles supported by anchors and soil nails Bnei Brak. Failure case: A wall with anchors that moves D. Within the framework of the existing standard, there are two types of anchors: cable anchors and anchors from treading rods (in addition to this, there are currently polymer anchors on the market made of films and/or round polymeric rods, which are not yet included in the standard and with which experience is limited). E. The anchors operate according to the principle of transferring the stresses acting on them from the structure, through the head of the anchor, to a stable area in the subsoil, outside the scope of mutual influence between them, which could cause a general failure (see attached anchor diagram). Drawing 1 - Geometry of ground anchors F. The front anchor part is connected to the structure using the anchor head system, adapted to the type of anchor (cable anchor, or rod anchor). The back part of the anchor is occupied, in a stable area of the ground and is anchored in it using cement mortar or resin mortar ("capture" area). The central part of the anchor passes through the ground which is in the "gliding circle", which is unstable. Therefore, the tread steel (cables or rods) is separated from the ground there, inside a flexible pipe. This area is defined as a "free section". G. All anchor components are designed against corrosion and corrosion, according to their existing period. The cement mortar is tested for its resistance against corrosion and all the tread steel and normal steel components are protected against welding, in accordance with what is required of the anchors. The synthetic anchor parts are protected against UV radiation, before their installation. In temporary anchors, at least one layer of protection against corrosion is required, while in permanent anchors two such layers of protection are required. H. The drilling of the anchors is done using a machine and equipment suitable for the type of soil, its stability and possible penetration to the groundwater level (more on soil drilling and their characteristics). I. According to the requirements of the standard, the production of the anchors will be done by a manufacturer with knowledge, technological ability and experience, who will be approved by a competent authority. J. Pouring an internal grout between the cables/treading rods and the threaded pipe allows, according to the standard, to consider this grout as a protective layer. Conditional on performing grouting under factory conditions, with high-quality cement grout, so that the amount and width of the cracks in the grout meet the requirements of the standard and comments on this topic, as detailed below). K. There is a requirement in the standard to protect the anchor components at all stages of execution. That is, from the moment it leaves the factory until it is installed in the hole designated for it. To protect the anchor, the production conditions must be taken care of, it must be transported to the site from the factory, and then it must be installed in the borehole. It can be understood that in the case of casting the "root" of the anchor in the factory, lifting it onto the truck, transporting it on the road, taking it off the truck, putting it down, lifting it again and inserting it (sometimes by force) into the borehole, could, with great certainty, cause many cracks, so that his wages were lost. In order to avoid such a thing, each anchor must be led in a designated template, which will prevent damage to it, until the moment of insertion into the borehole. Obviously, all this involves additional costs. The alternative is to establish a factory on the site, which is economical only in large projects, or to find another creative solution. L. After the anchors are installed, the standard requires that each anchor be stepped on to test the anchor's function on all its components. Only after this stage is completed can the anchor be locked in a planned work load. M. The standard requires that the entire process of monitoring and analyzing the findings be done by an experienced and qualified person, under the supervision of the inspector or another qualified body, when all the aforementioned bodies will be approved by the planner, in accordance with the documents presented. 3. Vision and reality in the field A. Issuance of general specifications between offices in 2005 and later, a detailed standard in 2011, were a milestone in the attempt to regulate the anchor industry, which had been operating for a long time before without regulated standardization and without clear procedures and rules, when the issue broke out and without a proper framework. The execution of the anchors then, was subject to special technical specifications issued by the planners, each according to his skills and understanding, without standardization. B. In many projects in the past, the execution of the anchors, their inspection and guidance, were carried out by the anchor contractors themselves without proper quality control and assurance, when the contractor is the operator and inspects himself at the same time. C. There is no doubt that the introduction of the specification and subsequently the standard contributed to raising awareness and the quality of the anchors produced, but not to the required extent and without proper supervision. At the same time, in recent years there has been a large increase in the number of anchor contractors entering the field. The intense competition led to a situation where the prices of the anchors dropped significantly (probably beyond the possibility of meeting all the requirements of the standard). One area that is particularly affected is the quality control over the installation of the anchors. There is currently a trend that contradicts the requirements of the standard, of going back to inspecting the anchors by the anchor contractors, despite what is stated in the standard and contrary to engineering logic. D. In the construction and infrastructure sector in the public and governmental sector, it is acceptable to carry out projects according to a quality procedure in which the contractor performs quality control as part of the agreement, while the client performs quality assurance. This issue is problematic in the field of anchors, which requires expertise and knowledge from the inspector. This procedure does not usually exist in the private market . E. In the prevailing situation in the field today, of the tough competition in the industry, the quality costs (quality control and assurance) and the additional time needed for high-quality execution of the anchors, there is a financial problem and a problem of schedules, both for the customer and the contractor of the anchors. The problems create repeated pressures on the planners and the management team. This could lower the quality of the product and endanger the project and the people. F. The Israeli standard for anchors has existed for ten years. It has not been revised yet, as required therein. It seems to me that it is time to re-examine the standard and update it, among other things to prevent further deterioration in the field, as detailed above. Encouraging news can be found in updated general specifications issued by Israel Railways in 2018. * Eng. Moti Yuger - union member, geotechnical cell, with a bachelor's degree and a degree in civil engineering, within the "Polytechnic Institute of New York". His specialization as part of his master's degree was in the field of foundation and geotechnical engineering. His professional activity as a freelancer, in the field of consulting for foundations and geotechnics, began in 1981, and in 2002 the firm moved to operate within the framework of Eng. The company specializes in solving difficult geotechnical problems and unique foundation methods in addition to its current activity. - Assisted in the preparation of the article, Eng. Shlomo Lieberman, from G.A.S. - Construction and Bridge Engineering Ltd. .

מהנדס קרקע וביסוס מהנדסים גאו-טכניים יעוץ קרקע וביסוס About Accessibility Statement - Yoger Engineers website Last update date: 12/10/2022 We, at the Yoger Engineers company website, respect all segments of the population. Therefore, we have drafted this accessibility statement to make it clear to you exactly what steps have been taken to ensure the inclusion and protection of all populations. The level of accessibility on the site The Web Content Accessibility Guidelines (WCAG) define requirements for designers to improve accessibility for people with disabilities. They define three levels of compliance: Level A, Level AA and Level AAA. Our website meets the AA accessibility level according to the WCAG standard. However, there may be exceptions and pages that do not meet this standard, in which case, please let us know and we will do our best to correct. The way we made the adjustments We made the adjustments through manual testing of various aspects of the site as well as through the accessibility wizard of the WIX platform, on top of which the site was built. The adjustments we made on the site In order to comply with the accessibility instructions, we have made several adjustments to the site. These include: Adjustments were made for browsing using a keyboard, trainings were made for the staff, the texts were written in a readable language, colors were chosen that make it easier for the users to read, all the images have a textual indication, the navigation structure of the site is fixed, you can use the keyboard and the mouse wheel to enlarge and reduce the text. Making contact and inquiries For any question or inquiry, the accessibility officer on the site will be available for you. You can contact her as follows: Alice French Phone: 09-8911401 Email: allis@engyuger.com

Lod train Construction of a train terminal, including an administration building, a fire station, extension of platforms and bridges at the Lod train station - an active and central station. The answer we gave in the project included: General concentration of the findings of the field investigation and geotechnical knowledge in the general area of the Lod train station. Accompanying the laying and foundation works in a large number of projects allows for a thorough acquaintance with the properties of the soil and possible execution methods.

A barge on stabilized soil using different techniques On the use of a barge on stabilized soil with different techniques - a lecture presented at the "Sixth Construction and Infrastructure Conference" of the "Association of Construction and Infrastructure Engineers" in November 2009. Alternatives to foundation solutions In this article we will present possible s olutions for the foundation using the "barge on piles" method, when instead of using reinforced concrete piles attached to the barge, "concrete pillars" or other material are used, while maintaining a space between them and the bottom of the barge in such a way that the stress applied to the barge, from the structure (vertical and horizontal) acts directly on the concrete columns. The purpose of the "pillars" is to serve as elements that stabilize and improve the properties of the soil mass in which they are installed, so that the combined mass can be attributed uniform improved mechanical properties when the system as a whole functions similarly to a barge on stilts, at lower costs. Another significant advantage is that the afore mentioned change allows the barge to be treated as a normal barge, based on land with improved properties, which simplifies the calculation of the barge, as a normal barge, with springs, relying on the new parameters determined by the land consultant. Barge on stilts In Israel and in the world it has been known for many years [Burland et al. (1977), Davis & Poulos (1972), Zeevaert (1957) ] (1979 (Hooper) ) as the method of establishing high-rise buildings and special buildings with heavy loads such as silos and storage tanks while combining barge and pilings when the pilings are mainly used as elements to reduce the subsidence expected in the barge. In this method the pilings are usually made as an integral part of the barge with a constructive connection between them. The piles in this method are calculated according to several alternatives: • A group of piles in a uniform distribution when the barge acts as a common head for the piles. In this situation the piles carry most of the load and the barge carries a small part of the load and the calculation is like that of a group of piles with a common head when the piles have an acceptable safety factor. • Piles evenly distributed under the barge, designed as "creeping" piles by calculating them for a tolerance of about 80% of the destruction tolerance and the total load between the piles and the barge is distributed accordingly. • Piles "creep" in an even distribution, where the piles are calculated for 100% of the load in destruction tolerance. In such a situation, the treatment of piles is only as subsidence reducers, while increasing the general security factor of the system. • Making groups of piles only in areas of heavy loads to reduce differential subsidence in the area of the barge, between more loaded and less loaded areas. With the development of the barge on stilts method and the experience gained, the question of the meaning and necessity of connecting the stilts to the barge was raised. When the piles are connected to the barge, most of the horizontal forces acting on the structure are transferred to the piles, due to their relatively high rigidity, and this can cause shear stresses and moments in the piles to the point of failure. This can require the addition of pilings beyond what is required to limit subsidence. In special buildings, where the useful loads are high and change (silos and silos), the connection also causes pullout forces in the piles that previously sank under the load that is removed afterwards. In light of this, they began making barges on piles without a constructive connection between them and even creating a space between the piles and the barge in such a way that the barge would not be in contact with the pile heads at all. As soon as there is complete separation between the piles and the barge, the reference to them can be changed and they can be seen as part of a system of stabilized and reinforced soil (1979, Hooper). One of the problems with the calculation methods of a barge on stilts as detailed above is the complexity and difficulty of the calculation. The calculation is essentially three-dimensional which also requires the use of advanced three-dimensional computer programs. This causes many engineers to shy away from the method, which therefore does not become common knowledge. Land stabilization and improvement There are currently several options for soil stabilization that can be used to improve the soil under the barge: • Stone pillars - with this method it is possible to drill, using modified methods, a borehole and fill it from the top with hard stone aggregate that will be tightened in stages using a vibrator. In cases where the bore is not stable, it is necessary to insert a corrective stepping stone into its lower part and tighten while lifting and tightening in stages which requires the use of special equipment. • Using the technology of Jet Grout columns - with this method, a drill is inserted to the planned depth and gradually raised while rotating and laterally injecting cement mortar at very high pressure in a way that produces columns of cement mortar that is also mixed with the local soil. • Drilling and casting of concrete columns using the "dry" method, or in case of stability and groundwater problems, drilling and casting using a CFA machine or bentonite technology. • Use of other reinforcing materials such as lime columns, thin concrete and CLSM, provided that their tolerance to the various troubles and their effectiveness in curbing subsidence are proven. calculation methods • As mentioned, one of the advantages of the application described above is that it allows for the simplification of the calculation method and bringing it to a situation where all that is required of the constructor is to calculate a normal barge on stabilized and improved ground that has the property of a spring coefficient proposed by (1867 Winkler), according to the relationship δ = κ ⋅ σ [where δ - the settlement at a certain point under the barge, κ - stiffness of the Winkler spring, or as it is called the "substrate modulus" and σ - the contact stress at the point]. As part of the development of stone and lime columns, different calculation methods were proposed, of which we have given her A weighted substrate number modulus was calculated for the methods described above for soil stabilization and improvement, such as by (Prof W. VanImple (1983) and (Dr H. Bredenberg (1983). An article was also published in 2002 (unsigned) by the Technion Institute titled Deep Mixing-Lime Columns in 2002. The mirror is also a calculation method. • Based on the above it is possible to calculate a weighted κ: Required data: 1. Determination of intervals x, y between the stiffening columns. 2. Finding the modulus of elasticity of the column and the ground. 3. Determining the cross-section dimensions of the column and its depth in the ground. Calculations: * The figure κtotal is used by the constructor for the barge calculations, while the calculation of the settlement in the structure can be performed by the foundation consultant, according to the shortening of the mass of the stabilized soil, plus the settlement in the ground below the stabilized soil. Summary The method simplifies the calculation of the foundation for the barge on the Winkler medium on the one hand and determining the properties of the medium on the other hand.

Commercial building in Har Tuv industrial area A second opinion that led to a change in the execution method in two supporting walls and saved a lot of time while reducing costs by hundreds of thousands of shekels The challenge: Deep excavations of up to 20 m in problematic soil (marlstone), near buildings and active infrastructure. Aspiration to avoid permanent and temporary soil anchors. The solution: The solution included changing the anchors to nails on the first wall and turning the second wall into a graded wall instead of an anchor wall. A series of calculations and tests was performed to examine different support solutions using a software. Working closely with the customer (executive contractor) while examining alternatives and adapting them to the constraints and preferences of the customer. Making tiered rows of piles with horizontal connection of concrete floors and making permanent soil nails, as an alternative to permanent soil anchors.

מהנדס קרקע וביסוס מהנדסים גאו-טכניים יעוץ קרקע וביסוס About Accessibility Statement - Yoger Engineers website Last update date: 12/10/2022 We, at the Yoger Engineers company website, respect all segments of the population. Therefore, we have drafted this accessibility statement to make it clear to you exactly what steps have been taken to ensure the inclusion and protection of all populations. The level of accessibility on the site The Web Content Accessibility Guidelines (WCAG) define requirements for designers to improve accessibility for people with disabilities. They define three levels of compliance: Level A, Level AA and Level AAA. Our website meets the AA accessibility level according to the WCAG standard. However, there may be exceptions and pages that do not meet this standard, in which case, please let us know and we will do our best to correct. The way we made the adjustments We made the adjustments through manual testing of various aspects of the site as well as through the accessibility wizard of the WIX platform, on top of which the site was built. The adjustments we made on the site In order to comply with the accessibility instructions, we have made several adjustments to the site. These include: Adjustments were made for browsing using a keyboard, trainings were made for the staff, the texts were written in a readable language, colors were chosen that make it easier for the users to read, all the images have a textual indication, the navigation structure of the site is fixed, you can use the keyboard and the mouse wheel to enlarge and reduce the text. Making contact and inquiries For any question or inquiry, the accessibility officer on the site will be available for you. You can contact her as follows: Alice French Phone: 09-8911401 Email: allis@engyuger.com

דף הבית / About / About Us Yuger Engineers was founded in 1981 and specializes in providing geotechnical consulting services to entrepreneurs, the largest and leading companies in Israel, the Israeli government (including the Ministry of Construction and the Ministry of Defense), municipalities and local councils. We are committed to the success of our clients and operate from a deep understanding of the business challenges they face. Therefore, we made it our goal to harness our engineering excellence and our decades of experience in the field to provide unique and creative solutions whose purpose is to save costs and execution time. Our position in the engineering market in Israel as an authority in the field for the business and public sector. Also, our company is engaged in providing legal opinions as an expression of our professional superiority and validation with the authorities. Our team Eng. Moti Yuger Founding Partner & Chief Engineer Moti Yoger has over 40 years of experience in the field of soil and foundation consulting, including several years at the American consulting company "Woodward & Clyde Consultants", one of the leaders in the field of soil engineering in the world. He holds a bachelor's degree (Bsc) in civil engineering and a master's degree (Msc) in soil engineering from the Polytechnic Institute of New York and previously served as a soil engineering lecturer at the Givatayim College of Technology and the Rupin seminary in Emek Hefer, and as a committee member and consultant for standardization. As a leading figure in the field of land consulting in Israel, Moti Yoger implemented for the first time in Israel several methods and technologies of grounding and soil improvement, including the CMC method - Concrete Modulated Columns. View More Eng. Daniel Zlusky Partner and Senior Engineer Graduated with a bachelor's degree in civil engineering (structures track - B. Tech) from Ariel University in 2011. Graduated with a master's degree in geotechnics track (ME) from the Technion in 2018. Worked in the company since 2011, partner in the company since 2018. View More Orit Peretz Lefler CEO Graduated with an LLB degree in law, with about a decade of experience in managing international companies that include business activity in developing markets in the Far East, Europe and Canada. Orit has extensive experience in the fields of regulation, international trade and business development. View More Eng. Khaled Hariri Engineer Graduated with a bachelor's degree in civil engineering - structures BSc and holds a master's degree in civil engineering (geotechnics) ME, from the Technion - Israel Institute of Technology. Licensed structural engineer with over 5 years of experience. Since 2019, structural, soil and foundation engineer. View More Eng. Maayan Mizrahi Civil engineer Graduated with a double bachelor's degree (B.Sc.) in civil engineering and geological and environmental sciences, Student for a research master's degree (M.Sc.) in civil engineering in the geotechnics track at Ben Gurion University. Former practitioner in various university courses. View More Eng. Daniel Levav Engineer Graduated with a bachelor's degree (B.Sc) in civil engineering with high honors, Ariel University. A master's degree student in the geotechnics track at the Technion. Former lecturer and practitioner in a variety of courses at Ariel University and Rupin College, as part of engineering and construction engineering studies. Has a seniority of over 3 years in our office. View More Eng. Ali Abed Al Jafar Engineer Graduated with a bachelor's degree (B.Sc) in civil engineering in the structures track with honors, a master's degree student (M.Eng) in the geotechnics and tunneling track at the Technion. Practicing courses at the Technion and the former Sami Shimon College. A registered structural engineer with two years of experience in construction planning. View More Avichay Rubin Geologist Graduated with a bachelor's degree. B.Sc in Geological Sciences with an engineering major - Ben Gurion University of the Negev. Graduated with a B.Sc degree in civil engineering - Ariel University in Samaria. Has 7 years of experience in the field of soil and foundation engineering. Wide experience in a variety of engineering projects from the fields of infrastructure and housing. View More Ziv Raz Manager of contracts and engagements Graduated with a bachelor's degree in industrial engineering and management, over 20 years of experience in management in the field of operations and logistics, with over 5 years of experience in managing operations and sales in the field of land and foundations. View More Hasida Butzer Welfare director View More Alice Zarfati S ecretary View More Alice Zarfati S ecretary View More

The Open University in Ra'anana The foundation of the university structure, which includes upper and underground parts in complex soil The challenge: The foundation of the structure, which includes 3 underground floors, in a challenging soil that includes a layer of clay mixed with metal oxides. The solution: Performing soil replacement to allow shallow foundation. The replacement of the soil was carried out using local clean sand from the surface. - Photo in the courtesy of Efrat Livne, The Open University -

The bridge over Boho river The project of the bridge over Boho river, in which Eng. M. Yuger served as a soil consultant on behalf of the contractor Sollel-Bona, was intended for the railway line from Ashkelon to Be'er Sheva and in accordance with the constraints of preserving the environment and the complex infrastructure for a railway bridge, and was a unique project in Israel. The bridge is located above Boho river , west of the city of Netivot, an environmentally sensitive area and for the purpose of building the bridge, it was necessary to carry out a strict and gentle process in regards to the preservation of nature. The project The planning began in November 2010 and the execution began in February 2011 and ended in October 2012 - the executing contractor was "Sollel Bona" and the land consultant on behalf of the contractor: Eng. Moti Yu ger. The bridge includes eight equal spans 32.5 meters long, 12 meters wide and 260 meters long. The bridge spans have a hollow circular section with a diameter of 4 meters and reaches a height of about 20 meters. The upper structure of the bridge consists of two massive prefabricated beams 2.2 m high, weighing about 200 tons each, cast on site and hoisted on top of the bridge girders. After placing the beams, a 30 cm thick bearing plate is cast. The bridge is a continuous bridge with seams in the end commissioners and two internal commissioners, where some of the commissioners are harnessed to the lower structure. In the end commissioners and some of the internal commissioners, special EKH-type authorizations were assembled. These braces prevent displacements across the bridge and thereby also share the unharnessed commissioners with the journey in receiving the horizontal forces obtained from loads, such as centrifugal loads, wind loads and earthquakes. In the longitudinal direction of the bridge, the supports allow the movements in order not to receive large forces due to loads such as temperature, shrinkage and creep. The documents were designed to receive horizontal forces of up to 200 tons. A detailed interaction calculation (bridge rail) was made for the bridge using MIDAS CIVIL software in accordance with the European standard EN 1992-2. Quality control during execution During the casting of the prefabricated beams, a discrepancy was opened by the contractor's quality control regarding the strength of the concrete that came from one of the mixers for casting the beam. Two separate tests were conducted by two different test institutes. According to the results of Institute No. 1, a compressive strength was obtained at the age of 28 days of 66 MPa compared to 5.30 MPa according to the results of the second Institute. At this point it was decided to wait for the concrete strength results at the age of 50 days to verify the results. Upon receiving results after 50 days, it was decided to conduct an in-depth examination to clarify the issue. The actions taken: The instruction to remove cylinders in suspicious places in order to be sure that there is concrete of low strength in a certain area of the beam. For this purpose, a typical beam casting was followed in order to discover the location of the defective mixer. A meeting with the concrete technologist to clarify the issue. Schmidt hammer test, which is a test that allows you to get an idea about the differences in the density of the concrete in different areas. The test does not give the strength of the concrete but only indicates changes in its uniformity. As mentioned, in order to give instructions for removing cylinders to test the strength of the hardened concrete in the places where the low-strength concrete was poured, a basic sketch was made, based on the order of casting the beam, for the location where the weak concrete is suspected. The execution of this sketch was possible only thanks to the execution engineer who documented in an orderly manner the order and method of casting that were actually carried out. The results of the rolls obtained definitely showed a decrease in the strength of the concrete: Rolls No. 1,2,3 in the area of the weak concrete showed the strength of the concrete lower than planned - Rolls No. 4,5,6 in the normal area showed the strength of the concrete as planned. At this stage, an in-depth examination was made into the way the problem was handled and after additional tests, consultations with the client of the work and the project manager, it was decided to reinforce the beam in order to qualify it for full function as planned. Despite many pressures to approve the beam because there was a laboratory test that proved that the strength of the concrete is 60 and the concrete technologist's claim that the concrete that arrived at the site is definitely of the 60 type, it was decided to carry out an in-depth examination of the issue in order to eliminate the smallest possibility that there is concrete with a lower strength than planned. It should be noted that the inspection could not have been done without full cooperation on the part of the contractor and on behalf of the quality control on the part of the contractor. Thanks to the in-depth inspection that was done, a concrete beam with a lower strength than planned was discovered and corrective measures were taken. Published for the first time in the newspaper of the Union of Construction and Infrastructure Engineers, Issue No. 66

TMA 38/1 Usishkin Tel Aviv An existing building based on slabs on top of thick clay near the groundwater level (contrary to the standards and construction methods used today). The challenge: Creating a stable structure that resists cracking. The common method is to make deep piles in groundwater at a high cost. This is compared to a creative solution by a barge. The solution: The stiffening of the structure by tying all the elements of the structure in a barge to force a uniform behavior.

Ha'Imahot Street, Tiberias The construction of Ha'Imahot Street road in the marlstone area was problematic - a method of execution saved millions of shekels The challenge: Marlstone area is prone to landslides, a fact that did not allow the completion of the road to the west. In addition to the road, the last structure towards the additional road section slid towards the northwest, towards the road. The solution: Before we got involved in the project, a very complex solution that included piles and permanent anchors in marlstone was proposed. We proposed an alternative solution of "stilt farms" only, where the road itself is a concrete surface cast on the stilts. The piles were 90 cm and 110 cm in diameter and 50 m deep, and were built as a grid across the width of the road to its western end. The assessment of the execution rate of the piles with the existing equipment in Israel was 1 pile every two days, but with the help of an imported machine the actual rate was 1-2 piles per day. The solution resulted in a huge saving of time and money estimated in millions of shekels at the very least.