Finite Element Analysis for Clay Inclined Wall Earth Dam of Baiyinhua Reservoir

Abstract

Baiyinhua Reservoir is located in Oumulun River, Ar khorchin banner in Inner Mongolia. The irrigation area of design is 53600 mu, and it is a medium-sized reservoir which is given priority to with irrigation. This article gives the stress and deformation distribution during construction and operation which has done the three-dimensional simulation analysis for clay inclined wall earth dam of Baiyinhua Reservoir using the finite element method, providing some reference for the design and construction of clay inclined wall earth dam. The results show that clay inclined wall earth dam of Baiyinhua Reservoir satisfy the design requirements and is safe and reliable. The results show that during operations the structural stress all is stress for clay inclined wall earth dam of Baiyinhua Reservoir, and the displacement of dam is very small. This shows that the structural design is safe, reasonable and consistent with the design requirements of earth dam structures. KeywordsBaiyinhua reservoir; Clay inclined wall earth dam; Finite element analysis; Simulation analysis; Stress distribution. I. ENGINEERING SITUATION Baiyinhua Reservoir is located in Oumulun River, Ar khorchin banner in Inner Mongolia. The irrigation area of design is 53600 mu, and it is a medium-sized reservoir which is given priority to with irrigation[1]. The total capacity of reservoir is 4.02 million m, normal water level 24m, design flood water level 28.1m, check flood level 30.3m. Hub engineering is composed of the main and auxiliary dam, spillway, and two water pipes. The main dam is clay inclined wall earth dam, which is 11m length, 740m long and 4m width. Dam was built on sand and gravel layer, using clay as the foundation seepage blanket measures, and the project is located in cold areas, the upstream of inclined wall located the protective layer of sand material[2]. II. FINITE ELEMENT MODEL Establishing finite element model of clay inclined wall earth dam of Daiyinhua Reservoir, the tilt angle of dam upstream face and downstream face respectively is  16 and  20 , dam filling silty loam, dry bulk density of 1400 kg / m, the water content of 23%, the internal friction angle  14 [3-4]. The width of dam is 72.6m, and the finite element model takes 100m toward dam upstream face, 97m toward dam downstream face and 80m to the ground below [5-6]. Earth dam and bedrock FEM division are shown in Fig .1. Figure 1. Earth dam and bedrock FEM division Clay inclined wall earth dam and foundation model uses isoparametric block element which has 8-node[7]. The element is applied to three-dimensional model of the entity structure, have properties of plasticity, creep, swelling, stress stiffening, large deformation and large strain. The element has eight nodes and each node has three translational degrees of freedom[8-9] . Considering the mechanical characteristics of dam during operation[10],the following three cases are taken into account mainly: case 1, normal water level(5.9m depth) and structural weight; case 2, design flood level(8m depth) and structural weight; case 3, checking flood level (8.8m depth) and structural weight. III. SIMULATION ANALYSIS International Conference on Mechatronics, Electronic, Industrial and Control Engineering (MEIC 2014) © 2014. The authors Published by Atlantis Press 1187 A Stress Analysis The largest transverse compressive stress is -65.24 kPa for case 1. It appears in the middle of the bottom, and tensile stress doesn′t appear in transverse direction. The largest vertical stress is -131.99 kpa. It appears in the middle of the bottom, and tensile stress doesn′t appear in vertical direction. The largest transverse compressive stress is -65.80 kPa for case 2. It appears in the middle of the bottom, and tensile stress doesn′t appear in transverse direction. The largest vertical stress is -132.46 kpa. It appears in the middle of the bottom, and tensile stress doesn′t appear in vertical direction. The largest transverse compressive stress is -66.63 kPa for case 3. It appears in the middle of the bottom, and tensile stress doesn′t appear in transverse direction. The largest vertical stress is -132.85 kpa. It appears in the middle of the bottom, and tensile stress doesn′t appear in vertical direction. Dam transverse, vertical stress contours are shown in Fig .2, 3, and transverse, vertical stress cloud is shown in Fig .4 and 5 for case 2. ANSYS 10.0 NODAL SOLUTION