Investigation of a Leaking Water Line Beneath Residential Foundation on Expansive Soils

Three dimensional numerical simulation of residential building on shrink–swell soils in response to climatic conditions

“…For unsaturated soils, many researchers [11,16,[19][20][21][22][23][24][25] have used the slopes of the void ratio versus matric suction curve and of the soil water characteristic curve to calculate m s 2 and m w 2 in Eqs (5a) and (5b). This corresponds to assuming that the surfaces for the void ratio and the water content are surfaces AMNE and AMNE′ as shown in Figure 3(a) and (b).…”

“…To date, most researchers have used a two-step 'superposition' method to simulate a foundation built on shrink-swell soils (e.g., [9,12,[14][15][16][17][18][19][20][21]27]). In the first step, the differential movements of the ground surface bearing an ideally flexible weightless slab were calculated.…”

“…In the second step, soilstructure interaction was simulated when the flexible slab foundation was imposed on a surface, which had been distorted by moisture changes. Figure 7 shows a typical simulation of water leakage underneath a slab using this two-step approach [20]. The simulation for the first step can be divided into two categories.…”

“…Þ to calculate the volume change, then calculates the vertical movement by multiplying the volume change by an empirical parameter [12,[18][19][20]46]. The influence of the mechanical stress on the volume change of the shrink-swell soil is not numerically simulated [19,23,47,48].…”

“…Table I summarizes the existing research on slab foundations built on expansive soils. The limitations of most existing simulations for foundations on shrink-swell soils have been as follows (e.g., [6,[8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27]): (i) the influence of daily weather variations was not reasonably evaluated (usually either constant, or sinusoidal suction, or flux boundary conditions were used to simulate weather variations); (ii) the theory used to simulate the volume change of shrink-swell soils only represented some aspects of soil behavior (e.g., the foundation loading did not change the pore pressure or suction); (iii) the material properties were simplified (linear or log-linear elasticity, or most soil properties were dependent only on soil suction); (iv) simulation of the soil-structure interaction was either not included or did not reflect the real situation very well (e.g., the soil was considered to be a solid continuum without water, and the water flow was not simulated); and (v) the influence of the superstructure was not considered (the load distribution was idealized). To overcome these shortcomings, this paper presents a fully coupled, nonlinear, elastic, threedimensional numerical simulation for buildings on expansive soils in response to climatic conditions.…”