Seismic Responses of Zoned Earth-Fill Dam by Instrumentation and Finite Element Simulation

2016 ◽  
Vol 11 (6) ◽  
pp. 1271-1279
Author(s):  
Sirikanya Laosuwan ◽  
◽  
Tawatchai Tanchaisawat ◽  

Natural disasters recently occurred in the northern region of Thailand have been increasingly becoming an important issue with emphasis on the alarm and caution for damage and frequency of disasters which may cause major losses of human lives and properties. In May 2014, six provinces in the northern region of Thailand were affected by the earthquakes (the main shock of Mw 6.1 (Moment Magnitude by USGS) and hundreds of aftershocks including the one Mw 5.9 at most) that had the epicenters at Phan District, Chiang Rai Province (19.656°N 99.670°E). This research aimed to study the distribution of seismic accelerations at Mae Ngad Somboon Chon Dam in Chiang Mai. The accelerometers were installed at 3 positions in the dam, consisting of the crest, middle and base of the dam. The collected data were compared and analyzed by the Finite Element Method. Analyses of the Linear Elastic Model, the Mohr-Coulomb Model and the Hardening Soil Model with using the acceleration actually recorded at the dam were conducted to determine an appropriate analytical model. The results indicated that the accelerations obtained from the Hardening Soil Model were more suitable for actual accelerations among others. Therefore the behavior of the Hardening Soil Model is more realistic than that of the Linear Elastic Model or the Mohr-Coulomb Model.

2014 ◽  
Vol 633-634 ◽  
pp. 1058-1064
Author(s):  
Olga Sokolova ◽  
Darya Trubina

Finite element method is often used to solving composite geotechnical problems. Application of these programs demands special attention for models for the setting parameters and simulation of soil behaviour. The problem of model selection to describe the behaviour of soils for calculation of settlement is considered in test task applied to complex geotechnical conditions of Saint-Petersburg. Comparison of obtained settlement values is carried out in Linear Elastic model, Mohr-Coulomb mode and, Hardening Soil model. The results of calibration of parameters for geotechnical model from the use of the qualities of odometer testing are shown.


2016 ◽  
Vol 9 (2) ◽  
pp. 97
Author(s):  
Franto Novico ◽  
Sahudin Sahudin

Perencanaan pemecah gelombang yang baik seharusnya dilakukan tidak hanya dengan mempertimbangkan aspek geologi dan geoteknik namun juga arus sebagai gaya horizontal yang bekerja pada pemecah gelombang. Berdasarkan desain pemecah gelombang pada penelitian terdahulu, maka dilakukan analisa pemodelan pemecah gelombang yang difokuskan pada parameter arus yang bekerja di struktur pemecah gelombang. Kecepatan arus ditransformasikan menjadi gaya horizontal untuk masing-masing skenario model, dimana model dibuat dalam bentuk dua dimensi elemen terbatas dengan analisis linear elastis untuk setiap skenario model. Model telah dibuat dengan menerapkan 8 meter tinggi pemecah gelombang dan 1kN/m2 gaya horizontal untuk disimulasikan. Berdasarkan hasil yang didapatkan maka dapat diketahui bahwa perpindahan terbesar yang terjadi adalah sebesar 46,25 x 10-3 m. Sehingga gaya arus dapat dikatakan tidak menyebabkan keruntuhan atau perubahan yang besar pada struktur pemecah gelombang. Kata Kunci: Gaya Arus, Pemecah Gelombang TPI Pancer, Plaxis V.8.2 Achieving a good design of a breakwater should be completed not only considering a geology and geotechnical aspect but also calculating a current as horizontal force. Based on previous breakwater design thus, it has been completed analysis of breakwater model where a model was created with concentrate within current force on breakwater. Current velocity is transformed to horizontal force where two dimension finite element and linear elastic model were applied for each model scenarios. Model has been created within 8 meters high of breakwater and 1 kN/m2 of current force to be simulated. Based on the result, it can be seen the biggest displacement that occurred 46,25*10-3 m. Therefore, the breakwater does not have a big deformation or failure that caused by current force. Keywords: Current forces, Breakwater, TPI Pancer, Plaxis V.8.2


2021 ◽  
Author(s):  
Michael Breach

Abstract Elastic follow-up (EFU) is a complex and influencing phenomenon in pressure vessels and piping systems. It affects the performance of structural components at elevated temperatures. Quantification of elastic follow-up is challenging since it’s still not clearly defined in the ASME Boiler & Pressure Vessel Code. Pressure vessels and piping under operating load over time can exhibit mixed elastic follow-up trajectories due to inelasticity. Typically, secondary, and primary load are present at the onset which can redistribute over time due to strain accumulation and stress relaxation during elastic-follow-up. ASME Boiler & Pressure Vessel Code Div. 5, limits strain accumulation via criteria in regions outside of the elastic core. However, a method that directly addresses Elastic follow-up, would be advantageous in establishing actual margins against elastic follow-up during the design phase. The phenomenon has been well studied with various assemblages of uniaxial models, showing load and displacement controlled and mixed responses. This study will present a method of assessing elastic follow up in finite element models. The method is based on the R5 elastic follow-up factor (EFF) expression that has been readily derived in the uniaxial case and employed by authors. Essentially the Von Mises equivalent strains are obtained from both a linear elastic and inelastic 3D finite element models subject to thermal (secondary) and pressure (primary) loading. The linear elastic model establishes the hypothetical initial elastic stress and the inelastic model will map the inelastic response through time. The Von Mises equivalent strains are then substituted into R5 expression, which are obtained from the onset linear-elastic model and the time varying inelastic model to map the elastic follow up and through time. The results are benchmarked against uniaxial results having combined primary and secondary loading.


2018 ◽  
Vol 5 (1) ◽  
pp. 22-30 ◽  
Author(s):  
Hong Liu ◽  
Hanlong Liu ◽  
Yang Xiao ◽  
Qingsheng Chen ◽  
Yufeng Gao ◽  
...  

2017 ◽  
Vol 86 (6) ◽  
pp. 365-391 ◽  
Author(s):  
Michael Herty ◽  
Siegfried Müller ◽  
Nils Gerhard ◽  
Gaoming Xiang ◽  
Bing Wang

2020 ◽  
Vol 205 ◽  
pp. 07001
Author(s):  
Hans Henning Stutz ◽  
Peter Norlyk ◽  
Kenneth Sørensen ◽  
Lars Vabbersgaard Andersen ◽  
Kenny Kataoka Sørensen ◽  
...  

The increasing need for energy storage technology has led to a massive interest in novel energy storage methods. The energy geomembrane system is such a novel energy storage method. The concept of the system is briefly introduced, and a holistic numerical model of the system is presented. The model uses advanced finite-element techniques to model the energy storage system using fluid cavity elements. The developed geomembrane energy system is modelled with different constitutive models to represent the soil behaviour: a linear elastic model, a nonlinear Mohr-Coulomb model, and a hypoplastic constitutive model. The consequences of these different models on the results are studied. Hereby, the focus is the first inflation and deflation cycle of the system.


2018 ◽  
Vol 4 (1) ◽  
Author(s):  
Hadianti Muhdinar Pasaribu

Banyaknya pembangunan infrastruktur yang merupakan salah satu tolak ukur kemajuan suatu daerah menyebabkan terjadinya penyempitan lahan didaerah tersebut. Sehingga pemanfaatan ruang dan lahan sangat dibutuhkan untuk menunjang kemajuan pesatnya pembangunan infrastruktur. Salah satu inovasi terbaik dalam mengatasi masalah keterbatasan lahan adalah membuat bangunan bawah tanah sehingga memberi ruang yang lebih untuk pembangunan. Pembangunan yang cukup terbaru di Indonesia saat ini adalah pembangunan MRT (Mass Rapid Transit) yang dilakukan di Jakarta. Pembangunan ini dalam pelaksanaannya membutuhkan proses konstruksi terowongan (tunneling) dan galian dalam untuk tiap stasiunnya. Pada penelitian ini, penulis terpusat terhadap masalah galian dalam pada stasiun Senayan dari proyek konstruksi MRT Jakarta. Permasalahan terbesar dalam suatu pekerjaan galian dalam adalah adanya deformasi lateral pada dinding bangunan bawah tanah dalam hal ini yang digunakan adalah dinding diafragma (D-Wall) dan juga adanya penurunan tanah disekitar galian. Oleh karena itu, perlu dilakukan pengecekan agar tidak terjadi keruntuhan. Metode konstruksi yang digunakan pada stasiun Senayan adalah metode konstruksi Top-Down. Pada penelitian ini dilakukan analisis deformasi horizontal dan penurunan tanah menggunakan software Plaxis 3D dengan dua pemodelan tanah, yaitu model tanah Mohr Coulomb dan Hardening Soil. Hasil deformasi horizontal yang diperoleh menggunakan model tanah Hardening Soil lebih mendekati  monitoring dilapangan dibandingkan dengan model tanah Mohr-Coulomb. Penelitian ini berfokus pada bagian-bagian tepi pada dinding diafragma melengkapi jurnal sebelumnya yang berfokus pada titik tengah dari dinding diafragma. Besarnya deformasi horizontal pada tahap akhir galian (penimbunan kembali tanah hingga dasar muka tanah) di titik P#80 (di tepi dinding diafragma) tercatat pada monitoring inclinometer sebesar 4.15 mm, dan deformasi yang dihasilkan menggunakan model Hardening Soil sebesar 9.57 mm sedangkan  menggunakan model Mohr-Coulomb sebesar 16.05 mm. Hasil deformasi horizontal yang diperoleh menggunakan model tanah Hardening Soil lebih mendekati  monitoring dilapangan dibandingkan dengan model tanah Mohr-Coulomb meskipun hasil yang diperoleh cukup jauh dari monitoring dilapangan.  Kata Kunci : Galian Dalam, Deformasi Horizontal, Model Mohr Coulomb, Model Hardening Soil, Plaxis 3D  The number of infrastructure development which is one of the benchmarks of the progress of a region causes the narrowing of land in the area. So that the utilization of space and land is needed to support the rapid progress of infrastructure development. One of the best innovations in overcoming the problem of land limitations is to make the underground building giving more space for development. The most recent development in Indonesia today is the construction of MRT (Mass Rapid Transit) conducted in Jakarta. This development in its implementation requires tunneling and deep trenching process for each station. In this study, the authors centered on the deep trenching problems at the Senayan station from the Jakarta MRT construction project. The biggest problem in a deep trenching work is the lateral deformation of underground building walls in this case which is used diaphragm wall (D-Wall) and also the decrease of soil around the excavation. Therefore, it is necessary to check to avoid collapse. The construction method used in Senayan station is a Top-Down construction method. In this research, horizontal deformation and soil degradation analysis using Plaxis 3D software with two soil modeling, Mohr Coulomb and Hardening Soil soil model. The result of the horizontal deformation obtained using Soil Hardening Soil model is closer to monitoring the field compared to the Mohr-Coulomb soil model. This study focuses on the edges of the diaphragm wall complementing the previous journal focusing on the midpoint of the diaphragm wall. The magnitude of the horizontal deformation at the final stages of excavation (backfill) to P # 80 (on the edge of the diaphragm wall) was recorded in inclinometer monitoring of 4.15 mm, and the resulting deformation using the Hardening Soil model of 9.57 mm while using the Mohr model -Coulomb of 16.05 mm. The horizontal deformation results obtained using the Soil Hardening Soil model is closer to the field monitoring than the Mohr-Coulomb soil model although the results obtained are quite far from the field monitoring.Keywords: Deep Excavation, Horizontal Deformation, Mohr Coulomb Model, Hardening Soil Model, Plaxis 3D.


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