Issue 53

A. Namdar, Frattura ed Integrità Strutturale, 53 (2020) 285-294; DOI: 10.3221/IGF-ESIS.23.22 286 clay and composite ground were investigated [7-8], and soil mixture such as silty clay, soft Bangkok clay, fly and bottom ash mixtures, sand-clay mixtures using kenaf fiber reinforcement, chemical etc, were used to improve soil strength and stiffness [9-13]. With attention to the influence of the mineralogy on the soil and other construction materials [14-16], the bearing capacity of the soil is significantly controlled by the soil mineral. There are several types of research on the analytical, experimental and numerical analysis of the soil foundation, and the soil dynamic and static response evaluated with experimental, analytical and numerical results are reported in the literature [1-6, 14-15]. On the other hand, different prediction techniques were applied on mild steel pressure vessel, crack propagation, compressive failure surface of cement concrete, natural stone and concrete footing design [17-22]. To identify and apply the best results in the geotechnical engineering design the advanced technique for decision making is needed. However, the mechanical properties of soil interaction make the prediction of soil bearing capacity difficult. The goal of this study is to forecast the influence of mechanical properties of soil on bearing capacity of the mixed soil, and to predict each element of soil mechanical properties separately. To combine all the mechanical properties on the safe bearing capacity of the soil foundation, the arti fi cial neural network (ANN) is applied. M ETHODOLOGY he maximum dynamic load and the statics load individually or combined that can be applied on the soil foundation without the unallowable settlement, deformation and shear failure are called the safe bearing capacity of the soil foundation. The safe bearing capacity of the soil foundation is a margin safety in geotechnical engineering design. The mechanical properties of the soil play an important role in the soil foundation and they support structural stability in transferring load from the structure to the subsoil. The appropriate interpretation of soil experiments results significantly enhance quality of geotechnical engineering design. On the other hand, the mechanical properties of soil interaction make complex the prediction of the foundation soil bearing capacity. The mechanical properties of the mixed soil and the calculated safe bearing capacity are shown in Tab. 1. Fig. 1 shows a flowchart to explain the steps in this investigation. The entire study contains five steps which are review analysis, problem identification, data selection, statistical analysis and interpretation of results for drawing conclusions. The procedure of the present work includes the behavior assessment of optimum moisture content, density, angle of friction and cohesive of the mixed soil, and the evaluation of the safe bearing capacity through the artificial neural network. In this study, for the interpretation of soil experimental results, each mechanical property of soil versus safe bearing capacity is graphically proposed and compared. It is aimed at analyzing the effect of the optimum moisture content (OMC) (%), the density (kN/m 3 ), the angle of friction (deg) and the cohesive of soil (kN/m 2 ) on the safe bearing capacity of the soil separately. Fig. 2 shows the distribution of the optimum moisture content, the density, the angle of friction and the cohesive of the mixed soil. The following are the steps of the research methodology. Step 1, review analysis: The safe construction of a structure depends on the safe bearing capacity of soil foundation. The geotechnical engineering design of a soil foundation needs to decide if the soil behaves differently from place to place owing to the variation of the mineralogy and morphology of the natural soil. These combination parameters create a difficult situation to choose a safe bearing capacity in civil engineering project by the geotechnical designer. Step 2, problem identification: The mechanical properties of soil interaction make the prediction of soil bearing capacity complex. It is needed to find an effect of each mechanical properties on mixed soil safe bearing capacity and to present guidelines to find the best decision. The soil mixture is a technique based on the soil mineralogy and morphology to control soil strength and stiffness, but because of probability function in soil mixture design and development of unexpected results during soil mixture process, feasible techniques are to be applied on soil mixture in geotechnical engineering design and soil foundation strengthening. However improper soil mixture design or use of unsuitable mixed soil hurt the strength of the soil foundation and they lead to a collapse of the structural elements and the whole structure, consequently. Step 3, data selection: The several soil mechanic experiments need interpretation before application. The mechanical properties of the mixed soil and the calculated safe bearing capacity are shown in Tab. 1, that is reported in the literature. The distribution of the optimum moisture content, density, angle of friction and cohesive of the mixed soil analyzed and their influence on the safe bearing capacity at each mixture design are studied. This process is repeated for 31 soil mixture models and significant factors impacting on the safe bearing capacity are identified and explained. It is well known that with the increasing number of collected data from the geotechnical site investigation or the laboratory experimental soil simulation the accuracy of the statistical analysis is more accurate in prediction and assessment.