Table 3.5: Testing factorial for single-stage permanent deformation tests (at 7 days curing time)59 Figure 2.1: Guidelines for stabilization of soil (Texas DOT, 2005) Table 2.1: Stabilizer selection criteria (Louisiana Standard Specification, 2006) Table 2.2: Selection of stabilizer on soil properties (Indiana DOT, 2008) Figure 2.2: Flocculation and agglomeration of clay particles (Prusinki and Bhattacharja, 1999) stabilizer and water with subgrade soil. agglomeration is also a short-term process, which takes place within few hours of mixing the significant difference in optimum moisture content and maximum dry density with cement Figure 2.4: Moisture density relation of soil with cement (Gautreau et al., 2009) Figure 2.5: Moisture density relation of Suddha soil with lime (Umesha et al., 2009) shown in Figure 2.6. a soil having LL of 23% and PI of 10%. Furthermore, the effect of the porosity as well as Figure 2.7: Dielectric value of soil at different water contents (Zhang and Tao, 2006) Furthermore, they also observed considerable decrease in permanent deformation of the treated Figure 2.9: Deformation of materials under repeated loading (Lekarp, 1997) 2001). elastic response and plastic response is described by the shakedown limit (Werkmeister et al., However, other researchers (Lekarp, 1997; Wermeister et al., 2001) classified the aie Figure 2.11: Shakedown range of material behavior (Lekarp 1997) limit for the service loads in the pavements. Figure 2.12: Resilient modulus definition (Kim and Kim 2007). corresponding to that stress level (Figure 2.12). It is denoted by M, and is defined in equation Where, 6g = (61-63) and €, are maximum deviatoric stress and resilient/recoverable strain Apdagyei and Hussain (2010) used these three portable devices as described in Table 2.3 * for soil having PI >10 and 25% or more passing #200 construction. These data are generally recommended only for small scale project. Louisiana Practice 2.13) after assigning initial value for kg and k7 as zero and one, respectively as recommended. modulus with considering the effect of soil-moisture suction. They performed the resilient nodulus tests for four different clays (PI ranging from 0 to 52) in Minnesota by using NCHRP 1. 28A testing protocol. test in laboratory. Despite being a main cause of failure of flexible pavements, sometimes the permanent Figure 2.14: Typical permanent deformation curve under RLT test (Elliott et al., 1998) increases as the ratio of the principal stresses increases (Figure 2.15) Figure 2.15: Typical curve under multi-stage permanent deformation (Werkmeister, 2003° Figure 2.16: M, with confining stress and cyclic stress (Mohammad et. al., 2008) than the untreated soils. inferred from the same figure that the treated soils are more sensible to change in confining stress ‘igure 2.17: Repeated loading characteristic of soil at different stress ratio (Elliott et al., 1999) higher stress than that performed under same higher stress throughout the test. Figure 2.18: Matric suction on resilient modulus (Sawangsuriya et al., 2009) Figure 2.19: Resilient modulus at different matric suction (Yang et al., 2008) stress and decreases with the increase in deviator stress when suction increased from 50 and 150 * Based on standard proctor test analysis of these soils are presented in Table 3.1. Figure 3. 1: Soil used in this study 3.2 Classification of soils 3.3 Moisture-density of raw and treated/stabilized soils Figure 3.2: Automatic compactor for standard proctor test 3.4 Unconfined compressive strength (UCS) tests in the laboratory Figure 3.5: Schemetic diagram showing the selection of the stabilizer it is supposed to remove unevenness during preparation of the samples at both ends. 3.6.1 Resilient modulus test Figure 3. 6: MTS 810 machine (left) with sketch (right) used for the RLT tests AASHTO T-307. Table 3.3: AASHTO T-307 for resilient modulus of subgrade soil “Total load applied from actuator rod Figure 3. 7:Haversine shaped loading during RLT test (NCHRP I-28A,2004) Table 3.4: Testing factorial for resilient modulus tests (at 7 days curing time) "2 samples for 28 days curing time “” actual samples tested 3.6.2 Single-stage permanent deformation tests later in section 3.6.4. The proposed testing factorial for resilient modulus is presented in Table Table 3.5: Testing factorial for single-stage permanent deformation tests (at 7 days curing time) The data acquisition of the MTS machine for permanent deformation tests was adopted Initially, the static triaxial loading of the specimens were performed for soil 3 at different Figure 3.8: Setting up of sample on base plate for test. 3.6.3 Multi-stage permanent deformation test stresses but same stresses ratios as presented in Table 3.7. ind 12 in each condition of confinement were applied, i.e. three under three different confinin: Table 3.7: Selected loading sequences for multi-stage permanent deformation test factorials for Tube suction test is also presented on Table 3.4. Figure 4.1: Compaction curves of untreated soils compaction curves obtained for treated/stabilized soils are presented in Figures 4.2 through 4.6. Figure 4.2: Compaction characteristics curve for stabilized soil 1 with cement Figure 4. 4: Compaction characteristic curve for stabilized soil 3 with cement Figure 4. 5: Compaction characteristic curve for stabilized soil 4 with cement+ lime (1:1) Figure 4. 6: Compaction characteristic curve of stabilized soil 5 with cement Table 4.1: Change in compaction characteristics of soil with additives 4.2 Unconfined compressive strength Figure 4.7: Variation of UCS of with moisture content (soil 1) Figure 4.9: Variation of UCS with moisture content (soil 3) The raw materials were prepared at the selected moisture contents and mixed with the specific additive (cement, lime or lime + cement) at different percent to determine the percent of Figure 4.11: Variation of UCS with moisture content (soil 5) Figure 4.12: Variation of UCS with different water-cement combination (soil 1) additive contents for the study were selected and are presented on Table 4.3 . Figure 4.14: Variation of UCS with different cement-water combination (soil 3) Figure 4.15: Variation of UCS with different cement-water combination (Soil 4) Figure 4.16: variation of UCS with lime-water combination (soil 5: Figure 4.17: Variation of UCS with cement+lime-water combination (soil 5) The stress-strain behavior of the raw soil specimens were compared with the Figure 4.21: Stress-strain relationship for soil 3 with lime (MC;) Figure 4.20: Stress-strain relationship for soil 3 with cement (MC; Figure 4.23: Stress-strain relationship of soil 5 with different cement + lime (MC) 4.3 Resilient modulus test stress and 6 psi of deviatoric stress and are presented in Table 4.11. all soils at different water/stabilizer combination were statistically compared at 2 psi of confining Table 4.4: Resilient modulus of soil 1 (7 days curing period) "50 psi UCS * 150 psi UCS; S (1) = sample 1, S (2) = sample 2 "50 psi UCS, ~ 150 psi UCS; S (1) = sample 1, S (2) = sample 2 "50 psi UCS, ~ 150 psi UCS; S (1) = sample 1, S (2) = sample 2 Table 4.7: Resilient modulus of soil 3 (7 days curing period) 50 psi UCS, ” 150 psi UCS; S (1) = sample 1, S (2) = sample 2 We jai: gees OWENS ee ee “50 psi UCS, ~ 150 psi UCS; S (1) = sample 1, S (2) = sample 2 Table 4.8: Resilient modulus of soil 4 (7 days curing period) Table 4.11: Statistical analysis of resilient modulus data Out of all regression models discussed in chapter 3, only three models presented in using SAS are presented in Tables 4.12 through 4.18 for soil 1, 2, 3, 4, and 5, respectively Table 4.12: Summary of non-linear regression (soil 1) at 7 days curing period Table 4.13: Summary of non-linear regression (soil 2) at 7 days curing period Table 4.14: Summary of non-linear regression (soil 2) at 28 days curing period Table 4.15: Summary of non-linear regression (soil 3) at 7 days curing period Table 4.16:Summary of non-linear regression (soil 4) at 7 days curing period Table 4.17:Summary of non-linear regression (soil 5) at 7 days curing period Table 4.18:Summary of non-linear regression (soil 5) at 28 days curing period Figure 4.29: Measured versus predicted resilient modulus for soil 1 at MC3 (50 psi UCS) Figure 4.30: Measured vs predicted resilient modulus for soil 1 at MC; (150 psi UCS) Figure 4.31: Measured versus predicted resilient modulus for soil 2 at MC3 (50 psi UCS) Figure 4.32: Measured vs predicted resilient modulus for soil 2 at MC; (150 psi) Figure 4.33: Measured versus predicted resilient modulus for soil 3 at MC; (50 psi UCS) Figure 4.34: Measured versus predicted resilient modulus for soil 3 at MC3 (150 psi UCS) Figure 4.35: Measured versus predicted resilient modulus for soil 4 at MC3 (50 psi UCS) Figure 4.36: Measured versus predicted resilient modulus for soil 4 at MC3 (150 psi UCS) Figure 4.37: Measured versus predicted resilient modulus for soil 5 at MC3 (50 psi UCS) Figure 4.38: Measured versus predicted resilient modulus for soil 2 at MC3 (150 psi UCS) through 4.28. Figure 4.42: Resilient modulus of soil 1 at different water/cement ratio (for both 50 psi and 150 double layer and increase the contact between the clay particles. Figure 4.43: Resilient modulus of soil 2 at different water/cement ratio (for both 50 psi and 150 sure 4.44: Resilient modulus of soil 3 at different water/cement ratio (for both 50 psi and 150 Figure 4.45: Resilient modulus of soil 4 at different water/additive ratio (for 50 and 150 psi) cement only. Figure 4.46: Resilient modulus of soil 5 with different water/lime ratio (for 150 psi) Figure 4.47: Resilient modulus of soil 5 at different water/additive ratio (for 50 psi) Figure 4.49: Resilient modulus with curing period for Soil 5 (for 50 psi UCS) Figure 4.48: Resilient modulus with curing period (Soil 2 Table 4.19: Summary of effect of curing time on resilient modulus Figure 4.50: Resilient modulus with curing period for soil 5 (150 psi UCS) Figure 4.52: Variation of resilient modulus with PI of soil at MC, Figure 4.53: Variation of resilient modulus with PI of soil MC; Figure 4.54: Permanent strain of soil 1 with number of cycles (for 50 psi UCS) Figure 4.55: Permanent strain of soil 1 with number of cycles (for 150 psi UCS) Figure 4.56: Permanent strain of soil 2 with number of cycles (for 50 psi UCS) Figure 4.57: Permanent strain of soil 2 with number of cycles (for 150 psi UCS) Figure 4.58: Permanent strain of soil 3 with number of cycles (for 50 psi UCS) Figure 4.59: Permanent strain of soil 3 with number of cycles (for 150 psi UCS} Figure 4.60: Permanent strain of soil 4 with number of cycles (for 50 psi UCS) Figure 4.61: Permanent strain of soil 4 with number of cycles (for 150 psi UCS) Figure 4.62: Permanent strain of soil 5 with number of cycles (for 50 psi UCS) Figure 4.63: Permanent strain of soil 5 with number of cycles (for 150 psi UCS) Table 4.20: Vertical permanent strain of specimens (%) Figure 4.64: Permanent strain of soil 1 versus water/cement ratio for 7 days curing period permanent deformation behavior. Figure 4.65: Permanent strain of soil 3 versus water/cement ratio for 7 days curing period. Figure 4.66: Permanent strain for soil 4 versus water/additive ratio for 7 days curing period. Figure 4.67: Permanent deformation of soil 2 versus water/cement ratio for different curing period. Figure 4.68: Permanent strain of soil 5 versus water/lime ratio for different curing period Figure 4.69: Permanent strain of soil 5 versus w/additive ratio for different curing period. Figure 4.70: Multi-stage permanent deformation curves of soil 2 at MC, (for 50 psi UCS) Figure 4.71: Multi-stage permanent deformation curves of soil 2 at MC;( for 150 psi UCS) Figure 4.72: Multi-stage permanent deformation curves of soil 3 at MC,( for 50 psi UCS) Figure 4.73:Multi-stage permanent deformation curves of soil 3 at MC;( 150 psi UCS) Figure 4.74: Multi-stage permanent deformation curves of soil 5 at MC,( for 50 psi UCS) Figure 4.75: Multi-stage permanent strain curves of soil 5 at MC,( for 150 psi UCS) Figure 4.80: Multi-stage strain rate versus permanent strain with skakedown limits for soil 5 at MC, (for 50 psi UCS) Figure 4.82: Dielectric values of soil 1 at different moisture contents (7 day curing period) separates the good materials from the materials that are moisture susceptible. Figure 4.83: Dielectric values of soil2 at different moisture contents (7 day curing period) Figure 4.84: Dielectric values of soil 3 at different moisture contents (7 day curing period) Figure 4.85: Dielectric values of soil 4 at different moisture contents (7 day curing period) Figure 4.86: Dielectric values of soil-5 at different moisture contents (7 day curing period) Figure 1: resilient modulus of soil 1 at 14% moisture content Figure 2: resilient modulus of soil 1 at 17% moisture content Figure 11: resilient modulus of soil 4 at 35% moisture content Figure 12: resilient modulus of soil 4 at 39% moisture content Figure 13: resilient modulus of soil 5 at 42% moisture content Figure 14: resilient modulus of soil 5 at 46% moisture content Figure 15: resilient modulus of soil 5 at 52% moisture content Figure 16: Multi-stage permanent deformation of soil 2 at MC2 Figure 17: Multi-stage permanent deformation of soil 2 at MC3 Figure 18: Multi-stage permanent deformation of soil 3 at MC, Figure 19: Multi-stage permanent deformation of soil 3 at MC3 Figure 20: Multi-stage permanent deformation of soil 5 at MC> Figure 21: Multi-stage permanent deformation of soil 5 at MC3 Figure 23: Shakedown charts of soil 2 at 2 psi confining stress Figure 24: Shakedown charts for soil 3 at 4 psi confining stress
