Multiparametric Analysis of a Gravity Retaining Wall

The design of a gravity retaining wall should be simple to construct, quick to build and the best economic solution to a problem. This can be achieved by using advanced optimization methods. Since geotechnical engineers are not always able to determine the exact soil properties and other project data, an optimal design of a gravity retaining wall should also be determined for a wide range of input parameters. Therefore, a multiparametric analysis of an optimal designed gravity retaining wall was carried out. Optimum designs of gravity retaining walls were obtained for 567 combinations of different design parameters. Diagrams were developed to help engineers determine the optimum section of the wall, based on construction costs. An exhaustive search was carried out within the available parameters (project data). The parameters were ranked according to which had the most influence on the optimum cost of the gravity retaining wall and the utilization of multiple constraints. The most important parameter for the optimal cost of a gravity retaining wall is the height of the retained ground, followed by the shear angle of the soil, the soil–wall interaction coefficient, the slope angle and the variable surcharge load. The shear angle of the soil is most relevant to the bearing capacity and eccentricity condition, while the soil–wall interaction coefficient is most relevant to the sliding condition. Since European countries apply different load, material and resistance safety factors, the optimization model was developed in a general form, where different design approaches and unit prices could be applied. The case study provides an improved optimization model for selecting the optimal design of gravity walls, for engineers.

Factor Affecting the Magnitude and the Direction of the Pressure Exerted on the Gravity Retaining Wall

Gravity retaining wall are structures used to retain the soil by its weight .the stability of such type of walls depend on the magnitude and direction of the horizontal forces exerted by soil . it found that there is many factors affect the value and the acting point of acting. Based on this, a study was conducted to investigate the effect of water table, external vertical loads, sloping of the backfill and the type of the backfill soil. It show that, the value of the horizontal soil pressure increase from147KN/m' on dry soil to about 307 KN/m' as the soil become saturated.also,effect of external loads are studied , and show its increase the total horizontal forces of the soil pressure. Sloping the backfill soil behind the retaining wall also great effect on the earth pressure. The type of the backfill soil behind the retaining wall also investigated and found its effect of the earth forces.

Assessment of Rectangular Cavity in Concrete Gravity Retaining Wall using Finite Element Method

The design of the Gravity retaining wall (GRW) is a trial and error process. Prevailing conditions of backfill are used to determine the profile of GRW, which proceeds with the selection of provisional dimensions. The optimum section is having factors of safety of stability higher than the allowable values and stresses in the cross-section smaller than permissible. The cross-section is designed to fulfill conditions of stability, subjected to very low stresses. The strength of the material, which is provided in the cross-section remains unutilized. A computer program is developed to find stresses at various locations on the cross-section of GRW using the Finite Element Method (FEM). A discontinuity in the form of a rectangular cavity is introduced in the cross-section of GRW to optimize it. The rectangular cavity is introduced in the cross-section of GRW at different locations. An attempt is made in this paper to find the stress distribution in the gravity retaining wall cross-section and to study the effect of the rectangular cavity on the stress distribution. Two cases representing different locations are considered to study the effect of the cavity. The location of the cavity is distinguished by the parameter w, the effects of cases with varied was 0.2305 (Case-I) and 0.1385 (Case-II) are observed. The cavity, which is provided not only makes the wall structurally efficient but also economically feasible.