Predicting resilient modulus of fine-grained subgrade soils considering relative compaction and matric suction

The rapid development of industrialization, urbanization, and population of the society augments the rising amount of municipal solid waste (MSW). With the advantage of considerably reducing mass and volume of solid wastes and generating energy, the incineration is a widely used treatment method for MSW. During the incineration process, the organic substances contained in the wastes are combusted, and the massive residues are remained. Of the incineration residues, bottom ash takes up to 80–90%, and the remainders are fly ash along with air pollution control residues. Dealing with the municipal solid waste incineration (MSWI) bottom ash in a sustainable manner is the primary principle. Significantly, MSWI bottom ash has been successfully utilized in diverse beneficial applications in recent decades, especially in civil engineering applications. This paper investigates the mechanical properties and validity of MSWI bottom ash as applicable substitutes of conventional subgrade materials. For this reason, a series of direct shear and CBR tests are performed on specimens with different water contents and dry densities.

Section: Introductionmentioning

confidence: 99%

Mechanical Properties of Municipal Solid Waste Incinerator (MSWI) Bottom Ash as Alternatives of Subgrade Materials

Huang

Shi

et al. 2020

“…erefore, the matric suction and relative compaction should be incorporated in prediction models of resilient modulus. A new model by Zhang et al [20] is expressed as…”

Section: Resilient Modulus Modelsmentioning

confidence: 99%

“…With the concern to unsaturated soils, an increasing number of efforts were made (e.g., [16,[19][20][21][22][23][24]) to predict the resilient behaviour of subgrade soils, which are more accurate than those generally referring to unsaturated soils as saturated soils due to simplicity. e proposed experimental and theoretical methods broaden the knowledge of unsaturated soil in predicting the response.…”

Section: Introductionmentioning

confidence: 99%

A Review on the Resilient Response of Unsaturated Subgrade Soils

Chu

2020

Considering the great contribution of subgrade modulus to the overall performance of roads or railways, it is crucial to provide the best prediction of resilient modulus for their foundations. Incorporating the seasonal variation of moisture content, the resilient modulus variation of unsaturated soils will be accurately predicted. This paper aims to introduce and discuss the knowledge about resilient response of unsaturated soils and emphasize the effects of humidity. A literature review on resilient response of unsaturated soils is presented based on the previous studies. The affecting factors (i.e., wetting and drying, moisture content, and matric suction) were discussed. The prediction model development of the resilient response of unsaturated soils was presented. The limitations and advantages of the model were analyzed and compared. It reveals that the current models were limited regarding stress conditions, moisture content, matric suction, and soil types, and further studies are still needed to achieve a better understanding of resilient response of unsaturated soils.

“…e self-consolidation time of silt is long, which leads to large consolidation settlement and obvious deformation after loading [1][2][3][4]. e conventional methods of soft soil treatment include displacement method, drainage method, dynamic consolidation method, or combined consolidation method [5][6][7][8][9]. Alternative methods, which depend on dry jet mixing piles or cement fly-ash gravel (CFG) piles for driveway drainage, are relatively expensive.…”

Section: Introductionmentioning

confidence: 99%

Shear Behaviors of the Intersurface between Rice Straw Rope and Dredger Fill Silt: Experimental and Mechanism Studies

Chen

Shi

et al. 2020

The further development of land reclamation, port waterway, and wharf construction brings about proper treatments of dredger fill silt, while huge amounts of rice straw set aside in China argument rational disposal every year. Therefore, rice straw is bundled up as ropes, which represent as drainage body and reinforcement, to make eco-friendly treatment for dredger fill silt. This paper investigates the mechanical properties and validity of rice straw rope as certain treating material of dredger fill silt through a series of pull-out test, mass loss test, and tension test on specimens with different water contents and dry densities. The results reveal that peak value of interfacial shear strength rises with the increase of normal stress at the same immersion time, and in particular, it rises by up to 250.0% when the normal stress is 40 kPa. The tensile force of rice straw rope increases slowly with the rise of tensile displacement, and the failure mode changes from brittle to ductile with the rise of immersion time, which witnesses first rapid back slow degradation trend. The proper interfacial shear strength, tensile force, and reasonable degradation rate of rice straw rope make it ideal in drainage and consolidation of dredger fill silt.