Discussion of "Forms and sand transport in shallow hydraulic fractures in residual soil"

published_or_final_versio

Discussion of "Forms and sand transport in shallow hydraulic fractures in residual soil"

published_or_final_versio

Numerical simulation of pressure-controlled cavity expansion process in clay at constant volumetric expansion rate

published_or_final_versio

Twelve-month observational study of children with cancer in 41 countries during the COVID-19 pandemic

Introduction Childhood cancer is a leading cause of death. It is unclear whether the COVID-19 pandemic has impacted childhood cancer mortality. In this study, we aimed to establish all-cause mortality rates for childhood cancers during the COVID-19 pandemic and determine the factors associated with mortality. Methods Prospective cohort study in 109 institutions in 41 countries. Inclusion criteria: children <18 years who were newly diagnosed with or undergoing active treatment for acute lymphoblastic leukaemia, non-Hodgkin's lymphoma, Hodgkin lymphoma, retinoblastoma, Wilms tumour, glioma, osteosarcoma, Ewing sarcoma, rhabdomyosarcoma, medulloblastoma and neuroblastoma. Of 2327 cases, 2118 patients were included in the study. The primary outcome measure was all-cause mortality at 30 days, 90 days and 12 months. Results All-cause mortality was 3.4% (n=71/2084) at 30-day follow-up, 5.7% (n=113/1969) at 90-day follow-up and 13.0% (n=206/1581) at 12-month follow-up. The median time from diagnosis to multidisciplinary team (MDT) plan was longest in low-income countries (7 days, IQR 3-11). Multivariable analysis revealed several factors associated with 12-month mortality, including low-income (OR 6.99 (95% CI 2.49 to 19.68); p<0.001), lower middle income (OR 3.32 (95% CI 1.96 to 5.61); p<0.001) and upper middle income (OR 3.49 (95% CI 2.02 to 6.03); p<0.001) country status and chemotherapy (OR 0.55 (95% CI 0.36 to 0.86); p=0.008) and immunotherapy (OR 0.27 (95% CI 0.08 to 0.91); p=0.035) within 30 days from MDT plan. Multivariable analysis revealed laboratory-confirmed SARS-CoV-2 infection (OR 5.33 (95% CI 1.19 to 23.84); p=0.029) was associated with 30-day mortality. Conclusions Children with cancer are more likely to die within 30 days if infected with SARS-CoV-2. However, timely treatment reduced odds of death. This report provides crucial information to balance the benefits of providing anticancer therapy against the risks of SARS-CoV-2 infection in children with cancer

Solution of the bearing capacity problem by the slip line method Vol.

The authors have derived the bearing capacity factor Nq on sloping ground based on the slip line method and have verified it using finite difference analysis. The bearing capacity factor Nγ on sloping ground is obtained by an iterative finite difference solution of the slip line equations, and the results are close to those from laboratory testing. Design figures for Nγ on sloping ground are prepared for rapid engineering use. For earthquake loading, the authors have applied the concept of equivalent horizontal acceleration and have derived Nq and Nγ based on slip line analysis.The authors have derived the bearing capacity factor Nq on sloping ground based on the slip line method and have verified it using finite difference analysis. The bearing capacity factor Nγ on sloping ground is obtained by an iterative finite difference solution of the slip line equations, and the results are close to those from laboratory testing. Design figures for Nγ on sloping ground are prepared for rapid engineering use. For earthquake loading, the authors have applied the concept of equivalent horizontal acceleration and have derived Nq and Nγ based on slip line analysis.Department of Civil and Environmental Engineerin

Pressure-controlled cavity expansion in clay

Experimental studies and numerical simulation of experiments were conducted on pressure-controlled cavity expansion in clay. The modified Cam-clay model was used to describe the clay behaviour. The experimental data are in good agreement with the simulation results, indicating that the adopted numerical simulation procedure is a plausible and reliable technique to study the fundamental behaviour of pressure-controlled cavity expansion. A new parameter, cavity aspect ratio (CAR), was defined to better describe the cavity shape. Different phenomena during the cavity expansion process are thus studied numerically, and the results are presented in this paper. © 2006 NRC Canada.published_or_final_versio

Making of environmentally-friendly bricks using dredged marine clay

Theme: Environmental Geotechnics for Sustainable DevelopmentSession - Reuse of Waste: no. 16

Soil improvement using compaction grouting: a laboratory investigation on the confining pressure and injection rate in completely decomposed granite

Laboratory compact grouting was performed using a modified triaxial test on Hong Kong CDG (completely decomposed granite) soils to investigate the effect of effective confining pressure and grout injection rate on the compact grouting effect. In this study, compaction grouting was simulated by expanding a latex balloon inside a triaxial sample using de-aired water. When the balloon is expanded, it first needs to overcome the effect of the confining pressure of the soil; further expansion will compact and density the surrounding soil. The compact grouting effect can be control by measuring the total void ratio change during injection and the following consolidation. The injection rate was controlled by a GDS using a volume control technique. The results of the experiments showed that the effective confining pressure on soil specimen plays an important role in the effect of compaction grouting, and the injection rate has an effect on the rate of excess pore pressure dissipation but minor effect on soil density. © 2007 Taylor & Francis Group.link_to_subscribed_fulltex