Effect of a square tunnel on ground acceleration responses during earthquakes
To understand the effects of size and depth of a square tunnel on peak ground acceleration (PGA) during earthquakes, a finite element model was setup in PLAXIS 2D. The soil model built was modelled after soil conditions above the Bukit Timah Granite formation. Data from the 2014 Ferndale California...
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| Format: | Final Year Project (FYP) |
| Language: | English |
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Nanyang Technological University
2020
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| Online Access: | https://hdl.handle.net/10356/140113 |
| _version_ | 1826126296039555072 |
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| author | Tan, Reuben Jit Shen |
| author2 | - |
| author_facet | - Tan, Reuben Jit Shen |
| author_sort | Tan, Reuben Jit Shen |
| collection | NTU |
| description | To understand the effects of size and depth of a square tunnel on peak ground acceleration (PGA) during earthquakes, a finite element model was setup in PLAXIS 2D. The soil model built was modelled after soil conditions above the Bukit Timah Granite formation. Data from the 2014 Ferndale California earthquake was obtained to simulate the worst possible earthquake scenario in Singapore. The size and depth of the tunnel was varied during the analyses. A 6.0 m square tunnel was analysed at four different embedment depths, and the PGA results obtained were compared to PGA of the model without tunnel. It was determined that the deeper the embedment depth of a tunnel, the greater the horizontal PGA of the ground surface. The tunnel at depth of 0.8D had resulted in an amplification of almost three times compared to a case with no tunnel. The analysis of the effect of tunnel sizes on PGA was set at a depth of 0.6D. The results showed that the larger the tunnel, the higher the horizontal PGA recorded. The smallest tunnel, 3.0 m, was found to have little effect on the PGA. In contrast, the 12.0 m tunnel amplified PGA by almost five times. For the results obtained from both size and depth, the maximum PGA recorded was not always directly above the tunnel, but some distance away. |
| first_indexed | 2024-10-01T06:50:21Z |
| format | Final Year Project (FYP) |
| id | ntu-10356/140113 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T06:50:21Z |
| publishDate | 2020 |
| publisher | Nanyang Technological University |
| record_format | dspace |
| spelling | ntu-10356/1401132020-05-26T08:03:30Z Effect of a square tunnel on ground acceleration responses during earthquakes Tan, Reuben Jit Shen - School of Civil and Environmental Engineering Budi Wibawa CWibawa@ntu.edu.sg Engineering::Civil engineering::Geotechnical To understand the effects of size and depth of a square tunnel on peak ground acceleration (PGA) during earthquakes, a finite element model was setup in PLAXIS 2D. The soil model built was modelled after soil conditions above the Bukit Timah Granite formation. Data from the 2014 Ferndale California earthquake was obtained to simulate the worst possible earthquake scenario in Singapore. The size and depth of the tunnel was varied during the analyses. A 6.0 m square tunnel was analysed at four different embedment depths, and the PGA results obtained were compared to PGA of the model without tunnel. It was determined that the deeper the embedment depth of a tunnel, the greater the horizontal PGA of the ground surface. The tunnel at depth of 0.8D had resulted in an amplification of almost three times compared to a case with no tunnel. The analysis of the effect of tunnel sizes on PGA was set at a depth of 0.6D. The results showed that the larger the tunnel, the higher the horizontal PGA recorded. The smallest tunnel, 3.0 m, was found to have little effect on the PGA. In contrast, the 12.0 m tunnel amplified PGA by almost five times. For the results obtained from both size and depth, the maximum PGA recorded was not always directly above the tunnel, but some distance away. Bachelor of Engineering (Civil) 2020-05-26T08:03:30Z 2020-05-26T08:03:30Z 2020 Final Year Project (FYP) https://hdl.handle.net/10356/140113 en GE-02 application/pdf Nanyang Technological University |
| spellingShingle | Engineering::Civil engineering::Geotechnical Tan, Reuben Jit Shen Effect of a square tunnel on ground acceleration responses during earthquakes |
| title | Effect of a square tunnel on ground acceleration responses during earthquakes |
| title_full | Effect of a square tunnel on ground acceleration responses during earthquakes |
| title_fullStr | Effect of a square tunnel on ground acceleration responses during earthquakes |
| title_full_unstemmed | Effect of a square tunnel on ground acceleration responses during earthquakes |
| title_short | Effect of a square tunnel on ground acceleration responses during earthquakes |
| title_sort | effect of a square tunnel on ground acceleration responses during earthquakes |
| topic | Engineering::Civil engineering::Geotechnical |
| url | https://hdl.handle.net/10356/140113 |
| work_keys_str_mv | AT tanreubenjitshen effectofasquaretunnelongroundaccelerationresponsesduringearthquakes |