我国北方新生代玄武岩地下水化学特征及其成因——以河北省张北县为例

为了进一步了解我国北方新生代玄武岩地下水的赋存规律和形成演化机理,以河北省张北县玄武岩地下水为研究对象,在野外采集地下水样、测定水化学和同位素组成的基础上,利用统计分析、离子比例系数、氢氧同位素、反向地球化学模拟等方法,对区内玄武岩地下水的水化学形成机制进行了研究。结果表明:沿地下水径流方向,研究区内玄武岩地下水中多数离子质量浓度呈现增大趋势,补给区的地下水化学类型以HCO₃-Ca·Mg为主,TDS质量浓度多小于500mg/L,排泄区地下水中阴离子以Cl^-和SO₄^2-为主,阳离子以Na⁺为主,TDS质量浓度多大于1 400mg/L;研究区地下水补给来源为当地大气降水;硅铝酸盐、岩盐、硫酸盐的风化溶解是地下水中离子的主要来源;溶滤作用、阳离子交替吸附作用和农业施肥等人类活动影响是控制地下水化学形成的主要作用。     

Seismic response for an isosceles triangle hill subjected to anti-plane shear waves

Acta Geotechnica - This paper presents an exact, analytical solution to the boundary value problem of the anti-plane (SH) waves scattering by an isosceles triangle hill on an elastic half-space by...     

Coupled thermal–hydraulic modeling of artificial ground freezing with uncertainties in pipe inclination and thermal conductivity

Acta Geotechnica - Artificial ground freezing (AGF) has been widely used as a temporary soil stabilization and waterproofing technique in geotechnical practices (e.g., tunnel construction). Many...     

Kinematic responses of a pipe pile embedded in a poroelastic soil to seismic P waves

Acta Geotechnica - In this paper, the kinematic responses of a pipe pile embedded in a poroelastic soil layer with rigid substratum under time-harmonic seismic P waves are studied with analytical...     

Predicting tunnel squeezing using support vector machine optimized by whale optimization algorithm

Acta Geotechnica - The squeezing behavior of surrounding rock can be described as the time-dependent large deformation during tunnel excavation, which appears in special geological conditions, such...     

Strengthening mechanisms in cement-stabilized kaolinite revealed by cross-scale nanoindentation

Acta Geotechnica - The macroscale mechanical properties of cement-stabilized soil have been widely reported, but the microscale behavior remains largely unexplored. This paper presents the first...     

A unified constitutive model for cemented/non-cemented soils under monotonic and cyclic loading

Acta Geotechnica - In this paper, an elastoplastic constitutive model is proposed to uniformly describe the mechanical behavior of cemented/ non-cemented soil under different loading conditions. A...     

DEM studies on the effect of particle breakage on the critical state behaviours of granular soils under undrained shear conditions

Acta Geotechnica - A number of discrete element analyses of undrained triaxial shear tests on crushable assemblies are performed using 3-dimensional particle flow code (PFC3D). The undrained shear...     

Effects of reinforcement ratio on seismic performance of hypothetical stations determined by full-scale central column tests

Bulletin of Earthquake Engineering - The reinforcement ratio of central column member has remarkable effect on the seismic behaviour of double-box stations. To investigate the effects of...     

Numerical simulation of deep-hole resistivity anomaly caused by drilling construction in Xinfengjiang geoelectric station

The Xinfengjiang reservoir in Guangdong Province, is one of the large reservoirs that have triggered earthquakes of magnitude greater than 6. Numerous earthquakes have occurred since the impoundment of the reservoir, making it one of the most active seismic zones in south China. In 2015, a set of deep-hole resistivity anomalies was observed in the Heping geoelectric station in Dongyuan county, located near the Xinfengjiang reservoir. After a field investigation, we found that a planned well drilling construction of new measuring channels was being carried out during that corresponding period of time. After careful comparison and analysis on the basis of the collected raw data, we had a reason to believe that drilling construction, rather than the inducement of the Xinfengjiang reservoir, was the main culprit for those unusual georesistivity values. So as to verify the above conjecture, we constructed a series of 3D finite element models based on the geological and hydrological information around Heping station and analyzed the drilling disturbances, respectively. Some significant conclusions were finally drawn according to the precise numerical simulation. This study gives a good example by combining numerical simulation with engineering practice as a way to understand the root cause of georesistivity anomalies in reality.