Smart system for safe and optimal soil investigation in urban areas

This paper discusses the challenges and diffculties experienced during soil investigation in urban areas using drilling machines and soil sampling.The focus is on the consequences of a lack of data on the subsoil profile and presence of utilities,which could cause major accidents with severe economic and social losses,resulting in constriction activities being delayed and urban services being disrupted.This paper describes certain accidents related to soil investigation in Qatar and their consequences,as well as the lessons learned from these accidents.In order to meet the challenges of soil investigation in urban areas,this paper presents a solution based on smart tech-nology,which includes:(i)a geotechnical information system with update data concerning the soil profile,soil surface,utilities locations,and water table level;(ii)tools for data management,analysis,and visualization;and(iii)a user interface that allows authorities,com-panies,and citizens to access authorized data via a graphic interface,update data,and send messages and alerts in the case of any inci-dent occurring.Finally,the paper presents a promising perspective for the development of smart drilling devices,which record data related to the functioning of a drilling machine and transmit data to the smart soil investigation system.

Study on Relative Soil and Water Conservation Benefits of Ridge Tillage in Different Terrain Conditions in the Black Soil Area of Northeast China

Ridge tillage, which is a very common and important tillage measure in the black soil area of northeast China, has some soil and water conservation bene- fits, but has little attention. It is very important to explore the spatial distribution of the ridge direction of the arable land and its soil and water conservation benefits in different terrain conditions in the black soil area. So Binxian County of Heilongjiang Province was selected as the study area, and 168 field investigation units were ex- tracted by stratified sampling method and investigated. According to equations of slope gradient factor and slope gradient in ridge direction, and based on the soft- ware of Arcmap, SPSS and Excel, the investigation data of soil and water loss in Binxian County were analyzed and counted, The results show that in plain, hilly and mountainous areas, the average ground slope gradients are 1.92°, 6.20° and 8.27° respectively, and the average slope gradients along ridge direction are 1.33°, 4.52°and 6.45° respectively, which account for about 70%, 73% and 78% of the average ground slope gradients in the same terrain condition; the relative quantities of soil erosion in the present ridge tillage condition account for about 55%, 69% and 67% respectively of that in down-slope ridge tillage conditions, so the present ridge tillage has obviously relative soil and water conservation benefits. Based on these results, the reasons of the present ridge tillage status were analyzed, and some reform measures were proposed. The results could not only help to comprehend the spatial distribution and soil and water conservation benefits of ridge tillage in the black soil area of Northeast China, but also provide scientific references for the layout of local soil and water conservation measures.

Effects of heavy metal pollution on farmland soils and crops:A case study of the Xiaoqinling Gold Belt,China

This paper focuses on the heavy metal enrichment and heavy metal pollution degree associated with mining activities in some crops and the soils of different parent materials in the Xiaoqinling Gold Belt.According to the geochemical analysis results of the soils observed in the gold belt,the soils are most highly enriched in Pb,followed by Cr,Cu,and Zn.Furthermore,they are relatively poor in Hg,Cd,and As.It is also shown that the heavy metals in all kinds of soils have the same geochemical characteristics in the gold belt.As for the crops(such as corn and wheat)in the gold belt,Zn and Cu are the most abundant elements,followed by Pb and Cr.Meanwhile,Hg,Cd,and As were found to have relatively low concentrations in the crops.The heavy metals in wheat and corn have the same geochemical characteristics in the gold belt in general.Compared to the aeolian loess soils and the crops therein,heavy metals are more enriched in diluvial and alluvial soils and the crops therein.As shown by relevant studies,the Hg,Pb,Cd,Cu,and Zn pollution are mainly caused by mining activities.Corn and wheat in the gold belt have a high tendency of risk exposure to heavy metal pollution since they are mostly affected by mining activities and feature high background values of heavy metal concentrations.Furthermore,wheat is more liable to be enriched in heavy metals than corn is grown in all types of soils.The Hg pollution in soils leads to Hg accumulation,increasing the risk of Hg uptake in crops,and further affecting human health.This study will provide a scientific basis for the control and management of heavy metals in farmland soils of mining areas.

Experimental study on self-burrowing dual anchor soft probe

This study focuses on the development and testing of a bio-inspired self-burrowing dual anchor soft probe for potential geotechnical applications.Dual anchor refers to the form of movement in soils in which some bivalve molluscs adopted by alternately generating anchoring effects in the soil through shell expansion and fluid-filled feet.By mimicking this mechanism,this study used pneumatic artificial muscles as soft actuators and developed an autonomous burrowing probe.The structure and the performance of the actuators and the probe were investigated and optimized.The burrowing-out process of the dual anchor probe was not a simple upward movement.Instead,it rose in the inflation phase and slipped downward in the deflation phase.The difference between the two was a stride in one single step.In the sands with relative densities of 30%,50%,and 80%,the total slips accounted for 18.8%,19.6%,and 26.9%of the total upward movements,respectively.Thus,the entire movement process showed a reciprocating upward trend.The burrowing process could be divided into a restricted stage and a free stage according to whether shear failure occurs in the overlying soil layer.When the soil density was high,the initial stage of burrowing was in a restricted stage.The amount of rise and slip were at a low level and increased slowly as the number of cycles increased.When the burrowing process was in the free stage,the increase was basically stable at a high value and accompanied by small slips.