# Taking into account tensile strength and softening material model in the load line

### Taking into account tensile strength and softening material model in the load line

The topic examined in the thesis was inspired by new materials in the construction industry. Most of the building materials used in today’s practice have been known for a very long time. Their properties and behavior are also known, the calculations are based on well-established methods and approximations. However, in the case of emerging substances, more precise calculations may be necessary to take advantage of the beneficial properties of certain materials.

In the material model of materials with low tensile strength compared to their compressive strength (e.g. concrete, loam), the tensile strength is traditionally neglected. This simplifies the calculation process and makes us wrong for safety. To improve the material parameters of concrete and loam, to increase the tensile strength, fibers are often mixed into the material. In my thesis, I examined how the load line affects these materials when the increased tensile strength is taken into account.

The paper is dr. Orbánné is based on the doctoral work of Ágnes [1] Csicsely. The thesis neglects the tensile strength of the loam, but takes into account the softening of the material on the depressed side. The load line is determined as follows: for specific normal force levels, the torque curvature function of the cross section is determined. The maximum of this gives the load capacity of the cross-section of the masonry, which together with the normal force is a pair of points of the load line.

During the research I further developed the results of the doctoral dissertation. [1] I also took into account the tensile strength in the material model and the possible softening on the drawn side. Based on the modified voltage diagrams, I drew the torque curvature functions and then the load line of the cross section. I used matlab for the calculation. By changing the input parameters, it became apparent how different material characteristics (increasing tensile strength or changes in the softening parameter) affect the load line.

[1]: Agnes Orbánné Csicsely, 2006. Doctoral dissertation “Experimental and theoretical load-bearing examination of loam walls”, pp. 41-54