Modeling of Transient Flow in Unsaturated Geomaterials for Rainfall-Induced Landslides Using a Novel Spacetime Collocation Method

<table class="table-group" id="tab1"><tr><td><table class="table"><tr><td class="thead-hr" colspan="3"><hr/></td></tr><tr class="thead"><td class="align_left" rowspan="2">Parameters for SWCC</td><td class="align_center" colspan="2">Soil type</td></tr><tr class="thead"><td class="align_center">Sandy soil</td><td class="align_center">Silty loam</td></tr><tr><td class="thead-hr" colspan="3"><hr/></td></tr><tr><td class="align_left">Saturated hydraulic conductivity (m/h)</td><td class="align_center"><span style="width: 58.3897ptpx;"><svg height="11.9413pt" id="M147" style="vertical-align:-0.3499002pt" version="1.1" viewbox="-0.0498162 -11.5914 58.3897 11.9413" width="58.3897pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M137 343C167 482 260 545 321 574C357 591 397 603 429 609L423 641C382 634 335 622 295 608C189 570 37 457 37 238C37 84 125 -12 242 -12C362 -12 447 89 447 209C447 311 374 393 267 393C247 393 226 386 204 376L137 343ZM227 337C318 337 361 256 361 173C361 105 336 22 258 22C176 22 126 120 126 240C126 266 127 291 132 310C155 323 189 337 227 337Z" id="g113-55"></path></g><g transform="matrix(.013,0,0,-0.013,6.24,0)"><path d="M113 -12C146 -12 170 11 170 46C170 78 146 103 114 103S58 78 58 46C58 11 82 -12 113 -12Z" id="g113-47"></path></g><g transform="matrix(.013,0,0,-0.013,9.204,0)"><path d="M241 635C89 635 35 457 35 312C35 153 89 -12 240 -12C390 -12 443 166 443 312C443 466 390 635 241 635ZM238 602C329 602 354 454 354 312C354 172 330 22 240 22C152 22 124 173 124 313S148 602 238 602Z" id="g113-49"></path></g><g transform="matrix(.013,0,0,-0.013,15.444,0)"><path d="M241 635C89 635 35 457 35 312C35 153 89 -12 240 -12C390 -12 443 166 443 312C443 466 390 635 241 635ZM238 602C329 602 354 454 354 312C354 172 330 22 240 22C152 22 124 173 124 313S148 602 238 602Z" id="g113-49"></path></g><g transform="matrix(.013,0,0,-0.013,24.59,0)"><path d="M528 54L331 254L528 455L492 493L294 291L96 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238 602Z" id="g113-49"></path></g><g transform="matrix(.0091,0,0,-0.0091,47.653,-5.741)"><path d="M556 236V289H56V236H556Z" id="g54-33"></path></g><g transform="matrix(.0091,0,0,-0.0091,53.213,-5.741)"><path d="M290 377C321 398 342 415 358 430C378 450 389 473 389 502C389 578 329 635 238 635H237C184 635 137 610 109 578L64 515L88 493C112 529 154 573 208 573S303 542 303 482C303 409 233 370 141 341L149 308C165 313 190 319 215 319C272 319 341 283 341 193C342 98 292 43 222 43C163 43 122 72 96 94C88 101 79 100 70 94C61 87 47 73 46 60C44 47 48 37 62 23C76 10 118 -12 165 -12C238 -12 430 62 430 223C430 297 379 359 290 375V377Z" id="g50-52"></path></g></svg></span></td></tr><tr><td class="align_left">Pore size distribution parameter (1/m)</td><td class="align_center"><span style="width: 58.3897ptpx;"><svg height="11.9413pt" id="M149" style="vertical-align:-0.3499002pt" version="1.1" viewbox="-0.0498162 -11.5914 58.3897 11.9413" width="58.3897pt" xmlns="http://www.w3.org/2000/svg" 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23C76 10 118 -12 165 -12C238 -12 430 62 430 223C430 297 379 359 290 375V377Z" id="g50-52"></path></g></svg></span></td></tr><tr><td class="align_left">Saturated water content</td><td class="align_center">0.50</td><td class="align_center">0.46</td></tr><tr><td class="align_left">Residual water content</td><td class="align_center">0.11</td><td class="align_center">0.14</td></tr><tr class="table-tr"><td colspan="3"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

<div>Unsaturated soil parameters used in the verification example 2.</div>

Geofluids

tab1

Table 1

Table 1: Modeling of Transient Flow in Unsaturated Geomaterials for Rainfall-Induced Landslides Using a Novel Spacetime Collocation Method 