Structural Design
Reinforced Concrete and Structural Design
We calculate the structural design of apartment buildings, buildings with ground-floor shops, offices and industrial buildings to TBDY 2018 and TS 500, and stay involved from the permit drawings to reinforcement questions on site.
Structural design of a reinforced concrete building
In a structural design we fix the position and size of the columns, shear walls, beams and slabs, and work out through which members the gravity loads and earthquake effects travel down to the foundation. We design apartment buildings, residential buildings with shops on the ground floor, offices and industrial buildings. The work usually comes to us from the property owner, the contractor, an investor or the project architect. If we are brought in while the architectural plan is still a sketch, we can place the columns together with the architect. When the job arrives after the plan is finished, either the shear walls have to be fitted into the plan or the plan has to be redrawn.
Buildings with an open ground floor used as shops and upper floors filled with masonry walls were among the building types heavily damaged in Gölcük in the 1999 Kocaeli earthquake. That is why we check the stiffness difference between stories, and whether the shear walls are evenly distributed in both directions of the building, in the very first model. Places where ribbon windows create short columns are discussed with the architect at that stage too. On the fill and alluvial ground along the gulf shore, we do not decide on the foundation before we have seen the geotechnical investigation report.
The structural design submitted for the permit and the drawings sent to site should not differ. We draw bar bending details, lap lengths and stirrup confinement zones clearly enough for the steel fixer to read the drawing without having to interpret it. On sloping plots we add the retaining wall calculation, and for high slabs the formwork and falsework calculation, to the same project when needed.
Scope of services
Residential and mixed-use buildings
Apartment buildings, blocks in housing estates and buildings with shops on the ground floor. We strike the balance between the opening wanted on the shop front and the need for shear walls on the floor plan itself.
Offices and shops
On floors that need long spans, we compare flat slab and ribbed slab options together with the story height and the routes for building services.
Industrial and warehouse buildings
Machinery and racking loads, openings to be added later. Where the roof is steel, we design the reinforced concrete columns and foundations for the support reactions of the roof.
Foundations
We choose the foundation type from the bearing capacity and groundwater information in the geotechnical investigation report. On fill ground where differential settlement is expected, a mat or a piled foundation may be needed.
Permit design
The structural design and calculation report submitted to the municipality and the building inspection firm, and the replies to correction letters received during the review.
Construction drawings and site
The formwork and reinforcement drawings used on site. We answer questions from the foreman or the site manager, with a revised drawing if needed.
Applicable regulations and standards
We carry out the seismic analysis to the Turkish Building Earthquake Code (TBDY 2018). The seismic hazard parameters of the plot, the local site class (ZA–ZF) from the geotechnical investigation and the occupancy class of the building together determine the seismic design class. The ductility level of the structural system (high, limited or mixed) is chosen within that framework. TS 500 (the Turkish standard for the design of reinforced concrete structures) governs section design and reinforcement rules, and TS 498 dead and live loads. At the permit stage the design is reviewed by the building inspection firm under the zoning legislation and Law No. 4708, and approved by the municipality. We arrange the calculation report in an order that lets the reviewing engineer find every load assumption and every check without searching.
How we work
Preliminary review
We ask for the zoning status certificate, the architectural sketch and the geotechnical investigation report if there is one. If the report is not ready yet, we say at the outset what information the calculation will need.
Column and shear wall layout
We set out the layout on the plan together with the architect. A shear wall arrangement that would cause torsional irregularity can often be spotted before any model is built.
Model and analysis
Using commonly used structural analysis software, we build the three-dimensional model, run the seismic and gravity load analysis and size the members.
Drawings and report
We draw the formwork plans and reinforcement details and write the calculation report. Before delivery we overlay the drawings on the architectural design floor by floor.
Review and permit
The building inspection firm reviews the design and the municipality issues the permit. We work in the corrections and reissue the drawings.
Site
We answer the questions that come up during formwork and reinforcement work. If a change is needed on site, we ask that work does not go ahead until the revision has been drawn.
Deliverables
- Structural and reinforced concrete calculation report
- Foundation plan and foundation reinforcement details
- Floor formwork plans
- Column, shear wall and beam reinforcement details; slab reinforcement plans
- Stair and special member details
- Summary of concrete and reinforcement quantities for the quantity take-off
- Revised drawings incorporating the corrections requested during approval
Frequently asked questions
Is a geotechnical investigation report needed for the structural design?
Yes. The local site class, bearing capacity and groundwater level are inputs to both the foundation design and the seismic analysis. The geotechnical investigation report is prepared by authorized firms and approved by the relevant authority. For the report process, see our geotechnical design page.
Who approves the permit design?
The building inspection firm reviews the structural design and the municipality issues the building permit. We prepare the design and deal with the correction requests raised during the review.
Can structural work start before the architectural design is finished?
Yes, and that is the right time to start. If the column and shear wall positions are discussed at sketch stage, the architectural plan does not have to be redrawn later.
How do you choose the ductility level?
By the seismic design class, the building height and the type of structural system. TBDY 2018 limits which options can be used depending on these, and on plots with high seismic hazard the choice narrows. We state the level we have chosen, with the reasoning, in the calculation report.
Do you also provide cost estimates?
Yes. Using the concrete and reinforcement quantities from the structural design, we prepare the quantity take-off, bill of quantities and cost estimate.
Examples from practice
Our projects in this field
Request a quote for your project
Write to us with the type of building, its location and the documents you have. We will agree the scope and timeline with you and send a written quote.