Strength Properties and Prediction Model of Cement-Solidified Clay Considering Organic Matter and Curing Temperature

Abstract

Cement-solidified clay (CSC) is an important filler material in land reclamation projects. Its strength is greatly affected by its organic matter content and curing temperature. This work reports an experimental study of the unconfined compressive strength (UCS) of CSC with respect to its initial water content w, cement incorporation ratio Aw, organic matter content Co, curing temperature T, and curing duration. A model (UCSOT) for predicting the UCS of CSC is established considering the influence of organic matter and curing temperature. A procedure to implement the model is proposed, and the accuracy of the model is verified. The results show that for a given curing duration, UCS decreases with increases in Co and w, and increases with increases in T and Aw. The influence of organic matter on the UCS is greatly affected by Aw, with a threshold of Aw = 15%. High-temperature curing increases the early and ultimate strengths of CSC, and organic matter increases this temperature sensitivity. Multiple regression characterization using cement content, w, and Co as independent control parameters accurately reflects the UCS at the reference temperature. On this basis, the UCSOT model established here considering the influence of organic matter and curing temperature has universal applicability.

Strength Properties of Cement-Solidified Dredged Sludge Affected by Curing Temperature

“…High curing temperature can accelerate the cement hydration, which accumulates more strength in reinforced material, and lead to a higher early and long-term strength. These conclusions are confirmed by the measured data [28,[42][43][44][45]. However, few studies have focused on the long-term behavior of cementstabilized clays at different temperatures.…”

“…When predicting the strength of CSC in practical projects, the independent variables Co and T corresponding to organic matter content and curing temperature can be considered, re- In addition, Figure 4b,c shows that, for a given C o (or C HA ) and curing age, the RCT values at different curing temperatures are similar, which indicates that the reduction degree of organic matter on the strength of CSC is not affected by the temperature. When predicting the strength of CSC in practical projects, the independent variables C o and T corresponding to organic matter content and curing temperature can be considered, respectively [43].…”

Effect of Organic Matter Components on the Mechanical Properties of Cemented Soil

“…As shown in Figure 9, a linear relationship was observed between the average structure factor and the unconfined compressive strength, represented by Equation ( 9). Additionally, a polynomial relationship was found between the average shape factor and the unconfined compressive strength, represented by Equation (10). Therefore, the unconfined compressive strength of cemented soil can be predicted based on the average structure factor and average shape factor.…”

“…Wang et al [9] used the limiting water content and the compressive strength as the evaluation indexes, investigated the influence law of the change of the content of the organic matter on the characteristics of the cement curing dredged sludge, and analyzed the mechanism of its action through microscopic experiments such as scanning electron microscopy. Cao et al [10] investigated the effect of organic matter content on the strength of cemented soil. As a result, the strength of cemented clay decreased with the increase of organic matter content, and based on this test and past data, a strength model suitable for predicting the strength of cemented soil with different organic matter contents was established.…”

Influence of fault forms on the evolution of concrete damage patterns in tunnels

“…Such a topographical environment will lead to an unfavorable geological environment, such as rock creep and hydrodynamic seepage (Bai et al, 2021;Bai et al, 2022). The deep buried headrace tunnel is prone to produce fault dislocation due to thermal hydraulic coupling effects (Bai et al, 2019;Cao et al, 2022). Jinping II Hydropower Station is located in the western mountainous region of China, with complex geological conditions such as faults, joints, and fissures development and rock fragmentation.…”