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It is well known that the prefabricated vertical drain (PVD) installation process generates a significant soil disturbance around PVD. This disturbed zone significantly affects the rate of settlement and excess pore pressure dissipation. However, the characteristics of these zones were still uncertain and difficult to quantify; there remains large discrepancy among researchers. This study aims to develop a simple analytical solution for radial consolidation analysis of PVD-installed deposit considering mandrel-induced disturbance.

The proposed solution takes into account the nonlinear distributions of both horizontal hydraulic conductivity and compressibility toward the drain. The proposed solution was applied to analyze field behavior of test embankment in New South Wales, Australia.

Both effects significantly increased the time required to achieve a certain degree of consolidation. The effect of hydraulic conductivity on the consolidation rate was more significant than the effect of compressibility variation. And, the increased compressibility in the soil-disturbed zone due to mandrel installation significantly increased vertical strain of the PVD-improved soil deposit. The predicted results using the proposed analytical solution were in good agreement with the field measurements.

A geotechnical engineer could use the proposed analytical solution to predict consolidation behavior of drainage-installed ground.

Consolidation behavior of PVD-installed ground could be reasonably predicted by using the proposed solution with considering variations of both hydraulic conductivity and compressibility due to PVD installation.

This paper aims to analyse the effect of soft soil grouting on the deformation of the closed shield tunnel with the measured data.

Combining the measured data of vertical, horizontal and convergence deformation of the adjacent tunnel during the grouting construction in foundation pit engineering, the influence of grouting on metro tunnel in soft soil area is analyzed.

The researches indicate that early grouting has the main effect on the horizontal displacement of the tunnel; Due to the disturbing effect of the uninterrupted grouting construction on the soil and the transfer pressure of the rheological soil to the bottom of the tunnel, the tunnel is obviously lifted; And the convergence deformation of the tunnel increases caused by the overburden pressure in the vertical direction, so that the tunnel appears the phenomenon of staggered seam, large opening of bolted joint, damaged segment even leakage of water.

The study based on the field monitoring data is rarely reported, especially the topic about inadvertent grouting in soft soil area is likely to cause severe deformation of adjacent metro tunnel.

The purpose of this paper is to investigate the effects of climate smart agriculture knowledge transfers. As well as to examine the application of climate-smart agricultural (CSA) knowledge such as conservation agriculture, irrigation systems, integrated soil fertility management, bioenergy and agroforestry by smallholder farmers in Kenya.

The study applied comparative research methodology to compare climate smart agriculture knowledge application between smallholder participants in farmer field schools (FFS) and no FFS participation. This study used household data from 759 randomly selected rural agricultural households in three counties in Kenya. The study applied multivariate probit model to estimate CSA knowledge application by farmers who participated in field trainings and non-FFS participation farmers.

This study established that climate smart agriculture knowledge transfer through FFS increases farmers’ application of critical aspects of climate smart agriculture knowledge practices such as irrigation system, conservation agriculture and soil and water conservation. Such aspects have been noted as effective interventions against adverse climate change effects such as persistent droughts and flooding and soil infertility. Further findings illustrated that farmers who received CSA knowledge transfers applied agricultural insurance to mitigate rising climatic risks on their farms. Knowledge transfer interventions targeting affordability through subsidizing agricultural insurance are probable and more cost-effective measures that can be used to reduce smallholder farmers’ exposure to climate change-related risks.

This study provides information that was previously unknown about climate smart agriculture knowledge transfers and application among farmers who participated in field trainings and non-FFS participation farmers by using empirical data.

The purpose of this paper is to describe cost effective structural design procedures to support catalytic reactors used in hydrocarbon industry. Three case studies are presented using various reactor models. Modularization and transportation challenges are also discussed. The scope of the paper is limited only to the structural and construction aspects. The chemical and mechanical designs are not covered in this paper.

Finite element strategies are developed to model load transfer to reactor’s supports and to simulate soil/structure interaction. Fictitious nodes are generated at bolt locations to transfer the reactor’s loadings from the skirt to the pile cap. Soil-pile interaction is modeled using horizontal and vertical springs along the pile embedded length. Flexible supports are used at the bottom of the piles to stimulate the end bearing of the soil bed. The approach is demonstrated for several case studies of reactors support system.

The described algorithm is accurate and computationally efficient. Furthermore, the procedure can be used in practice for design catalytic reactor support.

The paper provides very useful guidelines that can be utilized in practice for design of catalytic reactor supports system. The procedure is cost effective and computationally efficient.

Extensive efforts were made in the past to develop economical procedures for catalytic reactors design. Much of the work focused on the process and mechanical aspects of catalytic reactors. Very limited work addressed the structural design aspects. Furthermore, no guidelines are available in current codes of practice.

The purpose of this paper is to evaluate the co-seismic and post-seismic behaviors of an existed soil-foundation system in an actual alternately layered sand/silt ground including pore water pressure, acceleration response, and displacement et al. during and after earthquake.

The evaluation is performed by finite element method and the simulation is performed using an effective stress-based 2D/3D soil-water coupling program DBLEAVES. The calculation is carried out through static-dynamic-static three steps. The soil behavior is described by a new rotational kinematic hardening elasto-plastic cyclic mobility constitutive model, while the footing and foundation are modeled as elastic rigid elements.

The shallow (short-pile type) foundation has a better capacity of resisting ground liquefaction but large differential settlement occurred. Moreover, most part of the differential settlement occurred during earthquake motion. Attention should be paid not only to the liquefaction behavior of the ground during the earthquake motion, but also the long-term settlement after earthquake should be given serious consideration.

The co-seismic and post-seismic behavior of a complex ground which contains sand and silt layers, especially long-term settlement over a period of several weeks or even years after the earthquake, has been clarified sufficiently. In some critical condition, even if the seismic resistance is satisfied with the design code for building, detailed calculation may reveal the risk of under estimation of differential settlement that may give rise to serious problems.

The New Zealand (NZ) Government's commitment to a sustainable, low‐emissions energy future may be met, in part, by expanding bioenergy systems fuelled by short‐rotation forestry through utilising lower quality land affecting soil organic matter content and soil CO₂ flux. The purpose of this paper is to investigate the carbon sequestration potential of a range of soil conditioners in order to minimise or offset carbon emissions due to ground disturbance.

Seven soil conditioners are evaluated using incubation chambers to measure the affect of their incorporation within three NZ soil types on soil respiration.

Charcoal is found to produce a distinct and significant carbon sequestering trend, as did newspaper and whey. Conversely, vegetable oil, paper mill pulp, biodiesel and methanol showed overall carbon emitting trends.

The research is limited as only CO₂ is monitored within the incubation chambers rather than the whole gaseous carbon profile. No microbial observations are conducted.

The investigation concludes that of the conditioners observed, charcoal, newspaper and whey warrant further observation as carbon sequestration soil conditioners.

The study forms part of the foundations within the development of soil conditioners specifically designed for carbon sequestration.

The New Zealand (NZ) Government's commitment to a sustainable, low emissions energy future may be met, in part, by expanding bioenergy systems fuelled by short rotation forestry through utilising lower quality land affecting soil organic matter content and soil CO₂ flux. The purpose of this paper is to investigate the carbon sequestration potential of a range of soil conditioners in order to minimise or offset carbon emissions due to ground disturbance.

Seven soil conditioners are evaluated using incubation chambers to measure the affect of their incorporation within three NZ soil types on soil respiration.

Charcoal is found to produce a distinct and significant carbon sequestering trend, as do newspaper and whey. Conversely, vegetable oil, paper mill pulp, biodiesel and methanol showed overall carbon emitting trends.

The research is limited as only CO₂ is monitored within the incubation chambers rather than the whole gaseous carbon profile. No microbial observations are conducted.

The investigation concluded that of the conditioners observed, charcoal, newspaper and whey warrant further observation as carbon sequestration soil conditioners.

The paper forms part of the foundations within the development of soil conditioners specifically designed for carbon sequestration.

The shield tunnels closely constructed near the foundations have an inevitable influence on the structures, even results in the large settlement or uplift of the structures.

The comparison of structural deformation of three different foundations is presented based on the field monitoring data.

Shield tunnelling parameters vary for the different types of foundations. For the long pile foundations, the recommended speed is 3 to 4 cm/min, the grouting pressure is about 0.3 MPa and the grouting rate ranges from 150 to 180.

The study based on the field monitoring data is rarely reported, especially the topic about the structural deformation of different types of the foundations.

The purpose of this paper is to develop new constitutive models to predict the soil deformation moduli using multi expression programming (MEP). The soil deformation parameters formulated are secant (Es) and reloading (Er) moduli.

MEP is a new branch of classical genetic programming. The models obtained using this method are developed upon a series of plate load tests conducted on different soil types. The best models are selected after developing and controlling several models with different combinations of the influencing parameters. The validation of the models is verified using several statistical criteria. For more verification, sensitivity and parametric analyses are carried out.

The results indicate that the proposed models give precise estimations of the soil deformation moduli. The Es prediction model provides considerably better results than the model developed for Er. The Es formulation outperforms several empirical models found in the literature. The validation phases confirm the efficiency of the models for their general application to the soil moduli estimation. In general, the derived models are suitable for fine‐grained soils.

These equations may be used by designers to check the general validity of the laboratory and field test results or to control the solutions developed by more in‐depth deterministic analyses.

The purpose of this paper is to develop an appropriate machine learning model for predicting soil compaction degree while also examining the contribution rates of three influential factors: moisture content, electrical conductivity and temperature, towards the prediction of soil compaction degree.

Taking fine-grained soil A and B as the research object, this paper utilized the laboratory test data, including compaction parameter (moisture content), electrical parameter (electrical conductivity) and temperature, to predict soil degree of compaction based on five types of commonly used machine learning models (19 models in total). According to the prediction results, these models were preliminarily compared and further evaluated.

The Gaussian process regression model has a good effect on the prediction of degree of compaction of the two kinds of soils: the error rates of the prediction of degree of compaction for fine-grained soil A and B are within 6 and 8%, respectively. As per the order, the contribution rates manifest as: moisture content > electrical conductivity >> temperature.

By using moisture content, electrical conductivity, temperature to predict the compaction degree directly, the predicted value of the compaction degree can be obtained with higher accuracy and the detection efficiency of the compaction degree can be improved.