This report presents information on the characterization of cementitiously stabilized layers and the properties that influence pavement performance. It also contains recommended performance-related procedures for characterizing these layers and performance-prediction models for incorporation into the mechanistic–empirical pavement analysis methods. Individual chapters highlight pavement distresses of hot-mix asphalt pavements and concrete pavements, laboratory tests and model development, and model calibration. The material contained in the report will be of immediate interest to state materials, pavement, and construction engineers and others involved in the different aspects of pavement design and construction.

Characterization of Cementitiously Stabilized Layers for Use in Pavement Design and Analysis

Investigation of soil stabilization using chitosan biopolymer

This paper presents a case history of the leakage behavior during dewatering tests in the gravel strata of an excavation pit of a metro station in Hangzhou, China. The groundwater system at the tes...

Characteristics of groundwater seepage with cut-off wall in gravel aquifer. I: Field observations

Various applications of biopolymer-based soil treatment (BPST) in geotechnical engineering have been implemented in recent years, including dust control, soil strengthening and erosion control. Despite BPST methods can ensure the effectiveness of engineering while meeting environmental protection requirements, BPST technology requires further validation in terms of site applicability, durability, and economic feasibility. This study aims to provide a state-of-the-art review and future prospective of BPST. Current biopolymer types, engineered and assessed in laboratory scales, are described along with site implementation attempts. The effect of biopolymers on soil behavior is reviewed with regard to geotechnical engineering application and practice, including soil consistency limits, strength parameters, hydraulic conductivity, soil-water characteristics, and erosion control. The economic feasibility and sustainability of BPST application in ground improvement and earth stabilization practices is discussed. This review postulates biopolymers to be a promising new, environmentally friendly ground improvement material for geotechnical and construction engineering practice.

https://koasas.kaist.ac.kr/bitstream/10203/276070/1/000559046300002.pdf

Review on biopolymer-based soil treatment (BPST) technology in geotechnical engineering practices

Micro-structural analysis of strength development in low- and high swelling clays stabilized with magnesium chloride solution — A green soil stabilizer

Because of the high cost of quality construction materials, transportation engineers are often forced to seek alternative designs using substandard materials, commercial construction aids, alternative pavement materials, and innovative design practices. Nontraditional soil stabilization additives are being marketed as viable solutions for stabilizing marginal materials as a low-cost alternative to traditional construction materials. Nontraditional additives are diverse in their composition and the way they interact with soil. Unfortunately, little is known about their interaction with geotechnical materials and their fundamental stabilization mechanisms. The objective of this research was to advance current understanding of the chemical and physical bonding mechanisms associated with selected nontraditional stabilizers. The research consisted of conducting qualitative analyses of hypothesized stabilization mechanisms, examining historical literature for supporting documentation, and performing laboratory experiments to improve the understanding of how these nontraditional additives stabilize soils. Laboratory experiments included image analyses, physical characterization, and chemical analyses to determine the primary constituents of the mineral, soil, stabilizer, and stabilized soil composite. The focus of this effort was to provide insight into the proposed mechanisms by using the laboratory data to examine proposed mechanisms from the historical literature and to provide additional hypotheses for the interaction between nontraditional additives and different soil types.

Stabilization Mechanisms of Nontraditional Additives

Matting systems are used for temporary applications on soft soils to reduce ground pressure exerted by aircraft, heavy equipment, vehicles, and construction material. They have been used for military airfields, construction platforms, and similar applications. Previous evaluation studies of matting systems have typically consisted of full-scale testing, with only a limited amount of numerical modeling found in the literature. This paper presents results of full-scale accelerated testing of 21 test sections encompassing five matting systems, five soil-support conditions, and two aircraft loadings. One of the soil-support conditions was instrumented and tested in conjunction with three matting systems and one aircraft loading. Three-dimensional finite-element modeling was performed on the instrumented sections using the measured test data for calibration. Good matches of measured soil stresses were obtained with the model for two of the mats, whereas the model underpredicted stresses in the third mat. Modeling of the type performed in this paper was capable of correctly ranking the performance of the matting systems modeled relative to the full-scale test results.

Full-Scale Instrumented Testing and Three-Dimensional Modeling of Airfield Matting Systems

Laboratory evaluations were performed on several commercially available, rigid polyurethane foam (RPF) products to determine the suitability of using these materials for stabilization of base materials or as base replacement materials for full-depth portland cement concrete (PCC) pavement repairs. RPF specimens were prepared and tested to evaluate the compressive strength, reactivity, and density of several foam products. Additional tests were performed to determine the influence of aggregate size on the compressive strength and reactivity of the RPF materials as binders for aggregate. Results indicate that high-density RPF materials alone can provide compressive strengths similar to well-compacted soil or aggregate and may be applicable as base replacement materials. Results also indicate that further work is necessary to improve stone-on-stone contact and to reduce the amount of RPF necessary to create foam-aggregate composites for base stabilization. From these tests, field tests were recommended to verify that RPF materials generate sufficient strength to resist consolidation and prevent failure under traffic loads when placed in full-depth PCC pavement repairs.

Laboratory Investigation of Rigid Polyurethane Foams for Repair of PCC Pavements

: Pavement research and development in the military and civilian sectors have never been more necessary nor more visible than at the present time There are a number of reasons that point to the urgent need to accelerate the research and development efforts Some of the reasons that delineate this need include: the deterioration of our Nation's transportation infrastructure, increased congestion of our airports, proposed aircraft development of unprecedented size, depletion of paving materials and increased expense of existing pavement materials, and the increased dependence of our Nation's military on US bases to project forces for regional conflicts The objectives were to be achieved by evaluating the field performance of candidate materials through laboratory characterization and field test evaluations Additional areas of interest included in the investigation were the environmental impact of using the new or waste materials in pavement systems, the effect of these materials on the performance of the pavement including the maintenance and life-cycle cost of the pavement, and potential constructibility problems associated with their use

/pdf/material-utilization-in-military-pavement-systems-mumps-510gjnjayr.pdf

Material utilization in Military Pavement Systems (MUMPS) Program, FY 95

Blends of Type III Portland cement and select polymer emulsions were tested as potential soil stabilizers for airfield applications. The aim was to study increasing the early strength and curing time of emulsion polymer stabilization using blends of emulsion and Portland cement. Portland cement-stabilized specimens were prepared as conventional stabilizer controls. Each of the additives were added to a manufactured silty sand and compacted by a gyratory compactor at the optimum moisture content of 5% for the unmodified soil. Compacted specimens were cured in a controlled temperature and humidity environment for a maximum of 28 days. Samples were prepared at equivalent emulsion solids content of 2.75%. Portland cement was used at 6 and 9% dry weight for the control specimens and at 3% for the samples containing polymer/cement combinations. Stress-strain measurements were performed to determine the unconfined compressive strength and toughness under both wet and dry conditions. Results indicate that combinations of Type III Portland cement and polymer emulsions produce specimens with similar strengths and higher strains at yield compared to Type I and Type III cement alone. Cure time behavior indicates that the polymer-Type III soil cement blends build strength at a similar rate as Type III cement alone, yet may not have reached ultimate physical properties after 28-day cure times.

J Kent Newman

Papers

Stabilization Mechanisms of Nontraditional Additives

Full-Scale Instrumented Testing and Three-Dimensional Modeling of Airfield Matting Systems

Laboratory Investigation of Rigid Polyurethane Foams for Repair of PCC Pavements

Material utilization in Military Pavement Systems (MUMPS) Program, FY 95

Stabilization of Silty Sand Using Blends of Polymer Emulsions and Hydraulic Cement for Airfield Construction