Strut and Tie Topology for Reinforced Concrete Elements

14th INTERNATIONAL CONGRESS ON ADVANCES IN CIVIL ENGINEERING, İstanbul, Türkiye, 6 - 08 Eylül 2021, cilt.1, ss.1111-1116

Strut and Tie Model (STM) is a lower-bound design method for reinforced concrete members. It is usually

preferred for non-standard structural elements for which internal forces are not well-defined. In recent years,

studies and applications on STM have increased considerably. Topology optimization methods are generally

used to find struts and ties. Once locations and orientations of reinforcements are available, the design procedure

is rather easy to apply, even for complex geometries. However, finding the STM topology is not a straightforward

procedure. In this study, STM topology is obtained automatically by applying a simple algorithm. The

algorithm involves coupled computations carried out on an analog lattice model and a continuum model. The

stiffness of lattice elements is iteratively modified based on internal force distribution. Similarly, elasticity

modulus of continuum is modified based on principal stress distribution. During this process, redundant lattice

elements and continuum elements disappear. Lattice model and continuum model affect each other to arrive at an

optimized STM topology. Solutions obtained with the developed algorithm is compared with available

computational results from literature and good agreements are observed. Furthermore, STM topology for a nontrivial

geometry is presented to demonstrate the applicability of the methodology.