Very few studies have been carried out to investigate the durability and swelling behavior of dredged marine materials. To tackle this issue, this study mainly considers the influence of water immersion and thawing-freezing on the stress-strain characteristics and swelling property of 16 designed soil mixes with cement, lime, and Class-F fly ash. The unconfined compressive strength, failure strain, deformation modulus, and their quantitative corelationships are discussed in detail to evaluate the mechanical performance of stabilized materials damaged by water immersion and thawing-freezing. The result reveals that binder type and binder content have an important influence on the position and shape of stress-strain curves, compressive strength, deformation modulus, failure strain, and failure mode. The derived relationships between unconfined compressive strength and deformation modulus/failure strain are quantified, taking into account ageing effects. To quantitatively estimate the strength degradation, a coefficient of strength loss is defined for evaluating the effect of thawing-freezing and water immersion on compressive strength. Moreover, three-stage modes are proposed for depicting satisfactorily the stress-strain curves and swelling-time curves. A combination of relative swelling percent and absolute swelling amount, which can be reduced by chemical stabilization, is used to reasonably describe the swelling potential of stabilized soils.

Few studies have been reported about the effect of high curing temperature on the engineering properties of lime/cement-treated marine soils as alternative materials in road construction. Laboratory tests, including the stress-strain relationship, unconfined compressive strength, tensile strength, deformation modulus, and failure strain, have been systematically investigated to fill this gap. Some useful conclusions were developed from the results and discussions. The strength and modulus increase with cement content, curing time, and curing temperature, leading to a decrease in failure strain. Experimental analysis shows an appropriate lime content of about 3% when using a single lime treatment. Further addition has no beneficial effect in producing an improved construction material. Cement seems to be more effective than lime in speeding up the mechanical performance of problematic soils under high curing temperatures. Different from the strength ratio and modulus ratio, relationships such as UC...

The dredged marine sediments are classified as waste and how to deal with such kind of abandoned materials is a great challenge. The main objective of this experimental work is to provide a novel way to reuse dredged sediment as filling materials in road section. The laboratory dewatering test is performed to model the in situ evaporation and dewatering process of untreated and treated sediment with chemical binder. The impact of binder amount and time is discussed on the change of water content influenced by evaporation. To valorize dredged sediments as roadbed materials, a hydraulic binder is incorporated to investigate its effect on the bearing capacity and strength performance. The suitability of stabilized sediment is assessed based on the obtained mechanical results followed by a detailed discussion on the in situ test roads.

In this study, systematic investigations were conducted to solidify dredged marine sediments using the low-carbon composite binder made by mixing Ordinary Portland and calcium sulfoaluminate cement (OPC–CSA). A series of tests to evaluate physical and mechanical properties of samples, which indicated that the OPC–CSA composite binder could effectively improve the engineering characteristics of solidified dredged marine sediments, such as the immediate California Bearing Ratio (I-CBR) index, unconfined compressive strength, splitting tensile strength, and elastic modulus. In addition, simple models were proposed to correlate the unconfined compressive and splitting tensile strength with the elastic modulus of treated sediments. Importantly, the elastic modulus of treated sediments was defined by the local small-strain sensor method. In addition, the correlation between the strength and the three kinds of failure mode of the specimens was revealed. Lastly, simplified carbon footprint analysis indicated that OPC–CSA composite binder offers potential CO₂ emissions savings of 14%–41%. The laboratory tests have revealed that the mechanical and environmental behaviors of solidified dredged marine sediments meet the environmental and engineering requirements of the standards and regulations. Low-carbon and sustainable OPC–CSA composite binder-solidified dredged marine sediments could be reused as subbase or roadbed infill materials for low traffic.

Most of the previous studies concerning solidification of marine sediments focus mainly on the mechanical properties within the curing time of 90 days, but the long-term (e.g., 360 days) behavior has not been fully appreciated. The current study attempts to address this issue by analyzing the long-term strength and deformation behavior of sediments solidified with cement, lime, and fly ash. A series of unconfined compressive tests were conducted, and the effect of binder amount and binder type is discussed on 360-day cured specimens. It can be found that the increasing amount of cement/lime enhances the mechanical performance of sediments. The fly ash addition plays different roles in cement- and lime-solidified sediments. Fly ash improves the strength and modulus of lime-solidified sediments but weakens the mechanical characteristics of cement-solidified sediments. The test results demonstrate that the lime–fly ash binder is capable of replacing lime and cement–fly ash binder for sediment solidification from the viewpoint of economical cost and good ability to gain strength. The relationships of compressive strength vs. deformation modulus, compressive strength vs. failure strain, and compressive strength vs. tensile strength are quantitatively derived on 360-day cured specimens. The scanning electron microscope image analysis reveals the intrinsic microstructural mechanisms of improvement in the long-term mechanical performance of sediments due to the addition of chemical binders.