Engineering Properties Of Residual Soil Research Articles

Stabilization of Residual Soil from Wastewater Treatment Plant by using Bio-Enzyme (Terrazyme)

In India, the foremost important prerequisite for a project is performance criteria, economic feasibility and serviceability. The Traditional methods are laborious and don’t seem to be economically viable. Therefore, there is a need to innovate other ways to ensure serviceability as well as economic viability. In this Study, the effects on residual soil’s engineering properties due to bio enzymes are discussed. The soil stabilization with Terrazyme may be a well-established technique that became predominant worldwide due to its performance. There are numerous bio-enzymes that are used for the stabilization of soil like Terra-Zyme, Fujibeton, Renolith, Perma-Zyme, etc. These enzymes are demonstrated to be effective and economical. One among the main advantages of bio-enzymes is that they’re eco-friendly. Once we mix this terrazyme with different types of soils it modifies/improves the soil engineering and index properties. The effectiveness of Terrazyme relies on the quantity of addition, type of soil, and conditions on fields. The utilization of terrazyme for residual soils isn’t well known. In this study, Residual soils obtained from waste water treatment plant is used and its properties were found by conducting tests, it was found that the residual soil was not suitable for any engineering purposes as its UCS was less and it had high water content, hence it was treated with terrazyme in different dosages to supplement the properties of residual soil and obtain its optimum. Treating residual soil with terrazyme improves engineering properties of residual soil to great extent such that UCS of residual soil increased by 250% by adding 2% of terrazyme.

Indexing the engineering properties of residual soils in the southern slopes of Mashhad, NE Iran

Residual soils are weathering products of rocks that are commonly found under unsaturated conditions. The properties of residual soils are a function of the degree of weathering. A series of index properties, engineering properties and geophysics survey examinations were performed on residual soils from two major geological formations in Iran. In the present research, the index properties of residual soils in the south of Mashhad city in Iran are investigated. Natural and artificial trenches were analyzed for evaluating the weathering profiles and collecting soil samples. Disturbed and undisturbed samples were obtained from each of the soil profile horizons resulting from weathering of different parent rocks. Subsequently, physical properties and mechanical properties of the soil samples were determined in accordance with ASTM standards. Also, the mineralogical composition, chemistry, and texture of the soil were evaluated in 51 profiles. The field observations showed the difference in the weathering profile of residual soils deposited on various rocks (igneous, sedimentary, and metamorphic). These profiles mainly consisted of two horizons including residual soil on top and saprolite at the bottom. The results of laboratory tests and geotechnical data showed that the properties of residual soil samples change by depth. Moreover, depending on the type of origin rock, the properties are different in various types of residual soils. In most of the samples, the moisture content of soil horizons was also increased by depth. Based on the unified soil classification (USCS), the soils of the upper horizons appeared to be classified as ML (Lean silt) and CL (Lean clay) while the soils of the lower horizons (saprolite zone) fall in SC (clayey sand), SM (silty sand), and SW (well-graded sand) classes. Moreover, the results demonstrated that the particle size of the soil was increased by depth. Comparison of results of the geotechnical tests showed that properties of residual soils are changed by variations of depth, weathering level, and type of parent rock. Considering the concentration of the number of lines and the concentration of the points of intersection, the length and dimension fractal of lineaments in the southeastern part of the study area, it is evident that this zone possesses weathering severity and soil thickness. Fieldwork data from this zone have also verified the severity of weathering conditions. The analysis of lineaments trends in different parts of the study area indicated that the lineaments with the NW-SE trend have a strong effect on weathering development. The weathering depth depends on the orientation of bedding joints with respect to the slope in the study area. Slope inclination and soil thickness are controlled by weathering and erosion processes.

Microbially induced carbonate precipitations to improve residual soil at various temperatures

Microbial induced carbonate precipitation (MICP) has emerged recently as a new approach of green and sustainable soil improvement technique. The main aim of this study was to determine the most suitable temperature for MICP to improve tropical residual soil. The physical and engineering properties of residual soil used in the study were determined through several laboratory experiments. A urease active strain of Sporosarcinapasteurii obtained from American Type Culture Collection (ATCC) was used to trigger the carbonate precipitation. Experimental parameters such as curing temperature, treatment duration and bacteria to cementation reagents ratios were evaluated. The results show that the optimum temperature for MICP treatment of residual soil is 55°C. It was also found that at this optimum temperature, specimens treated with bacteria and cementation reagents in proportion of 2:1 produces the highest strength improvement ratio of 1.27 relative to untreated sample and calcite content of 1.09% after 7-day curing. The shear strength of the treated soil also increases with the increase in treatment durations as the 7 days curing produces higher strength improvement for all the experimental conditions. The specimens cured under the atmospheric temperature recorded the lowest calcite content and hence the lower shear strength improvement ratio. Moreover, the experimental results obtained from this study also can be used as a guide in the future bio-geotechnology researches and lead to further scope in geotechnical applications.

Engineering properties of residual soils in part of Southwestern Nigeria: implication for road foundation

The impact of roads on the socioeconomic development and progress of any country cannot be quantified. A geotechnical investigation of subsoils along Isinbode–Ara road, stretching in southeastern to northwestern direction of 7 km distance within Ekiti State, Southwestern Nigeria, was carried out. This investigation follows the British Standard Institution, such as moisture content, particle size distribution, specific gravity, Atterberg limit, compaction, consolidation and California bearing ratio. Results of investigation showed that the moisture content, specific gravity, liquid limit, plastic limits and plasticity index ranged from 7.2–25.9%; 2.64–2.77; 24.0–61.1%; 19.2–26.2% to 4.35–38.90%, respectively. Grain size distribution showed the fine and coarser fractions range from 13.0–66.5% to 32.6–84.8%, respectively. The maximum dry density and its optimum moisture content ranged from 1.48–2.07 g/cm3 to 11.3–30.3%, respectively. Soaked CBR results ranged from 3 to 44%. Two classes of subsoils, namely A-2-4 and A-2-6 (granular materials) and A-6 and A-7-6 (clayey soils), were identified and rendered suitable and unsuitable road construction materials, respectively. This investigation revealed that the subsoils are poor road construction materials due to its fine fractions and plasticities, which should be put into consideration during its foundation design and construction stages.

Improvement of Engineering Properties of Residual Soil of Tuff Breccia by Electro-Kinetic Method

This paper presents the results of an experimental study that was conductedto improve engineering properties of residual soil of tuff breccia by applying the electrokinetic method. The soil samples were taken from a slope in a high susceptible landslide area in the Kulon Progo, Yogyakarta, Indonesia. The electro-kinetic experiments were conducted using a clear glass tank of 60 cm 30 cm 30 cm size, a 13 V power pack to supply the voltage, and aluminum electrodes. The results showed that the pH value of anolyte decreased while that of catholyte increased during the treatment. The Atterberg’s limits of all soil samples decreased, while the shear strengths increased. XRD and SEM analyses indicated that there were no mineral changes after electro-kinetic experiments. However, the soil structure changed and became denser. The increased soil strength after electro-kinetic treatment would likely improve stability of natural slopes.

Characteristics and engineering properties of residual soil of volcanic deposits

Residual soil knowledge of volcanic-sedimentary rock products provides important information on the soil bearing capacity and its engineering properties. The residual soil is the result of weathering commonly found in unsaturated conditions, having varied geotechnical characteristics at each level of weathering. This paper summarizes the results of the research from the basic engineering properties of residual soil of volcanic-sedimentary rocks from several different locations. The main engineering properties of residual soil such as specific gravity, porosity, grain size, clay content (X-Ray test) and soil shear strength are performed on volcanic rock deposits. The results show that the variation of the index and engineering properties and the microstructure properties of residual soil have the correlation between the depths of weathering levels. Pore volume and pore size distribution on weathered rock profiles can be used as an indication of weathering levels in the tropics.

Effect of stabilizers on the shear strength of residual soil

In this paper, chemical stabilizer was used for soil characteristics improvement. Styrene Butadiene Rubber (SBR) polymer and lime is effectively used as an inexpensive and easily applied material for soil stabilization and its response performance was evaluated. This research studied improving the engineering properties of Residual soil by mixing it with varying percentages of chemical stabilizer. An evaluation of the effectiveness and performance of SBR and Lime as a soil stabilizer was performed over a series of laboratory tests for geotechnical soil properties. Residual soil used in this study was lateritic soil. The soil was mixed with various amounts of stabilizer for polymer (SBR) {2.5, 5, 10 and 12.5 %} and for lime {1.25,2.5,5 and 10%} by weight and then compacted at the optimum moisture content (OMC) and maximum dry unit weight (MMD). The original soil and the stabilized samples were subjected to unconfined compression test to determine their strength at different curing times (7,14 and 28 day). The results showed a reduction in the plasticity index. The results showed an increase in strength.

Hydraulic Conductivity of Residual Soil-Cement Mix

In Malaysia, although there are several researches on engineering properties of residual soils, however study on the hydraulic conductivity properties of metasedimentary residual soils is still lacking. Construction of containment walls like slurry wall techniques can be achieved with hydraulic conductivity of approximately 5 x 10-7cm/sec. The objectives of the study were to determine the physical properties of metasedimentary residual soils and to determine the influence of 1%, 3%, 5% and 10% of cement on hydraulic conductivity parameters. The coefficient of hydraulic conductivity of the soil naturally and soil-cement mixtures were determined by using the falling head test. According to the test, the hydraulic conductivity of the original soil was 4.16 x 10-8 m/s. The value decreases to 3.89 x 10-8 m/s, 2.78 x 10-8 m/s then 6.83 x 10-9 m/s with the addition of 1%, 3% and 5% of cement additives, respectively. During the hydration process, cement hydrates is formed followed by the increase in pH value and Ca(OH)2 which will alter the modification of pores size and distribution. When the quantity of cement increases, the pores size decrease. But, the addition of 10% cement gives an increased hydraulic conductivity value to 2.78 x 10-8 m/s. With 10%, the pore size increase might due to flocculation and agglomeration reaction. The generated hydraulic conductivity values will indirectly become a guide in the preliminary soil cement stabilization to modify the properties of the soil to become more like the properties of a soft rock.1. Introduction

Factors Affecting Improvement in Engineering Properties of Residual Soil through Microbial-Induced Calcite Precipitation

AbstractStudies of soil improvement by microbial-induced calcite precipitation (MICP) have focused primarily on fine sand. This paper explores the viability of the MICP technique for improving the engineering properties of a typical tropical residual soil. A species of Bacillus, B. megaterium, was used to trigger calcite precipitation. Four variables were considered in this study: the concentration of B. megaterium, the concentration of the cementation reagent, the treatment duration, and the flow pressure of the cementation reagent. The results show that the improvement in the engineering properties of the MICP-treated residual soils is comparable to those of treated fine sands. The preferable treatment conditions for the soil studied are B. megaterium concentration of 1×108 cfu/mL, cementation reagent concentration of 0.5 M, flow pressure of 1.1 bar of the cementation reagent, and treatment duration of 48 h. Using this combination of parameters, the obtained shear strength increase and hydraulic conduct...

Variability of residual soil properties

Rainfall-induced slope failures are commonly observed in residual soil. Due to weathering, the residual soil properties vary with depths, especially in tropical countries, such as: Singapore. Therefore, it is important to characterize the properties of residual soil with depth. Index properties, soil–water characteristic curve and saturated and unsaturated shear strength tests were carried out on residual soils from sedimentary Jurong Formation, Bukit Timah Granite and Old Alluvium in Singapore. The variations of residual soil properties in Singapore were determined from the laboratory test results and evaluated as a function of soil inherent variability. Typical, upper and lower bounds of soil properties for the residual soils in Singapore were described using confidence interval approach and coefficient of variation (COV) in this paper. The variations in residual soil properties can be incorporated in design based on risk or reliability approach. The COV of index and engineering properties of residual soils in Singapore indicate that residual soils from Bukit Timah Granite and Old Alluvium are coarser than residual soil from sedimentary Jurong Formation. The particle size distribution of residual soil from Old Alluvium is more uniform than that from Bukit Timah Granite. On the other hand, the particle size distribution of residual soil from Bukit Timah Granite is more uniform than that from sedimentary Jurong Formation. The shear strengths of residual soils from Bukit Timah Granite and Old Alluvium are higher than that from sedimentary Jurong Formation.

Engineering properties of residual soil derived from granite : Huang, Z L; Huang, C Proc International Conference on Engineering Problems of Regional Soils, Beijing, 11–15 August 1988P598–601. Publ Beijing: International Academic Publishers, 1989

Engineering properties of residual soil derived from granite : Huang, Z L; Huang, C Proc International Conference on Engineering Problems of Regional Soils, Beijing, 11–15 August 1988P598–601. Publ Beijing: International Academic Publishers, 1989

Indexing the engineering properties of residual soils : Vaughan, P R; Maccarini, M; Mokhtar, S M Q J Engng GeolV21, N1, 1988, P69–84

Indexing the engineering properties of residual soils : Vaughan, P R; Maccarini, M; Mokhtar, S M Q J Engng GeolV21, N1, 1988, P69–84

Indexing the engineering properties of residual soil

Abstract The geological study of the formation and structure of in situ residual soils is well advanced; the study of the engineering properties of these soils much less so. In particular, no methods exist whereby mechanical properties can be related to geological descriptions, or to simple index tests, as is done for sedimentary soils. The methods for sedimentary soils are inappropriate for residual soils, yet no alternatives have been developed. Most residual soils are weakly bonded, and they may have widely varying void ratios. A laboratory study of how these two features influence engineering behaviour is being conducted, based mainly on the testing of an artificial material in which both can be varied under control. Initial results from this study show that engineering behaviour depends on the void ratio of the soil related to that which the soil can have in the un-bonded ‘de-structured’ state. This indicates that it is useful to index the in situ void ratio of residual soils in relation to void ratio in the de-structured state, in a manner similar to the indexing of sands by relative density or of sedimentary clays by liquidity index. Simple methods whereby this may be done are suggested and discussed.

Engineering properties of residual soils from South-Central region of Brazil. 12F, 2T, 6R : VARGAS, M THEMAG ENGEN. SAO PAULO, BR PROC. 2ND INT. CONGRESS, LAEG, SAO PAULO, PAPER IV-PC-5, V1, 1974, 26P

Engineering properties of residual soils from South-Central region of Brazil. 12F, 2T, 6R : VARGAS, M THEMAG ENGEN. SAO PAULO, BR PROC. 2ND INT. CONGRESS, LAEG, SAO PAULO, PAPER IV-PC-5, V1, 1974, 26P