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高压 3

三峡工程 2

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压力容器技术 2

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Experimental study on concrete box culverts in trenches

Baoguo CHEN, Junjie ZHENG, Jie HAN

《结构与土木工程前沿（英文）》 2009年 第3卷 第1期   页码 73-80 doi: 10.1007/s11709-009-0008-3

摘要： Concrete box culverts are widely used in expressways in mountain areas. Many problems frequently take place due to improperly estimated vertical earth pressures on culverts. The prevailing Chinese General Code for Design of Highway Bridges and Culverts (CGCDHBC) stipulates the computation of the design load on culverts primarily based on the linear earth pressure theory, which cannot accurately describe the variation of the vertical load on culverts in trenches. In this paper, a full-scale experiment and numerical simulation were conducted to evaluate the variation of vertical earth pressures on culvert and soil arching in backfill. The variations of foundation pressure and settlement were also analyzed. The result revealed that the soil arch forms when the backfill on the culvert reaches a certain height. The soil arching effect reduces the stress concentration on the crown of the culvert but it is unstable. The vertical earth pressure on top of the culvert is significantly different from that recommended by the CGCDHBC

关键词： culvert     vertical earth pressure     soil arch     full-scale experiment     numerical simulation    

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Deviation correction strategy for the earth pressure balance shield based on shield–soil interactions

《机械工程前沿（英文）》 2022年 第17卷 第2期 doi: 10.1007/s11465-022-0676-4

摘要： The control system presently used in shield posture rectification is based on driver experience, which is marginally reliable. The study of the related theory is flawed. Therefore, a decision-making approach for the deviation correction trajectory and posture rectification load for an earth pressure balance (EPB) shield is proposed. A calculation model of posture rectification load of an EPB shield is developed by considering the interactions among the cutter head, shield shell, and ground. The additional position change during the shield attitude correction is highlighted. The posture rectification loads and shield behaviors results can be solved by the proposed method. The influences of the stratum distribution (i.e., bedrock height in the upper-soft and lower-hard strata) on shield behaviors and posture rectification loads are analyzed. Results indicated that the increase of pitch angle in the upper-soft and lower-hard strata causes a sharp rise in vertical displacement. The bedrock height increases the magnitudes of the required posture rectification moments when hr/D > 0.5. For a tunnel with hr/D ≤ 0.5, the variation of hr/D has little effect on the posture rectification moments. Finally, the posture rectifying curves based on the theoretical model are compared with the target ones based on the double circular arc interpolation method. The required results can be obtained regardless of the soil–rock compound stratum distribution. The maximum rectification moment in the rock layer is almost 12.6 times that in the soil layer. Overall, this study provides a valuable reference for moment determination and the trajectory prediction of posture rectification in compound strata.

关键词： additional position change     deviation correction trajectory     earth pressure balance shield     mechanical model     posture rectification    

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Upper bound solution to seismic active earth pressure of submerged backfill subjected to partial drainage

《结构与土木工程前沿（英文）》 2021年 第15卷 第6期   页码 1480-1493 doi: 10.1007/s11709-021-0776-y

摘要： In waterfront geotechnical engineering, seismic and drainage conditions must be considered in the design of retaining structures. This paper proposes a general analytical method to evaluate the seismic active earth pressure on a retaining wall with backfill subjected to partial steady seepage flow under seismic conditions. The method comprises the following steps: i) determination of the total head, ii) upper bound solution of seismic active earth thrust, and iii) deduction for the earth pressure distribution. The determination of total head h(x,z) relies on the Fourier series expansions, and the expressions of the seismic active earth thrust and pressure are derived by using the upper bound theorem. Parametric studies reveal that insufficient drainage and earthquakes are crucial factors that cause unfavorable earth pressure. The numerical results confirm the validity of the total head distribution. Comparisons indicate that the proposed method is consistent with other relevant existing methods in terms of predicting seismic active earth pressure. The method can be applied to the seismic design of waterfront retaining walls.

关键词： seismic active earth pressure     partial seepage flow     pore pressure     anisotropy     upper bound theorem    

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Experimental study on the stratum applicability and mechanisms of bubble–slurry for earth pressure balance

《结构与土木工程前沿（英文）》   页码 1387-1399 doi: 10.1007/s11709-023-0005-y

摘要： Soil conditioning is essential for addressing the stratum applicability problem of earth pressure balance (EPB) shields. Under high water pressures, EPB shields spew water and soil when excavating coarse-grained strata. Typically, foam combined with polymers and slurry is used to solve spewing. However, in current techniques, slurry, foam, and the other agents are mixed with soil separately, their synergistic effect is seldom realized. In this study, an anionic surfactant was used to foam in bentonite slurry to form bubble–slurry to maximize the synergy between bubbles and slurry. The slump, volume stability, and permeability test of bubble–slurry-conditioned sand was conducted to examine the conditioning effect, and the stratum applicability of bubble–slurry was determined from the perspective of permeability. It was found that the conditioning effect of bubble–slurry in coarse gravel soil was excellent and could expand the applicability of EPB shields. The main stabilization mechanism of bubble–slurry is that bentonite particles provide a space barrier for bubbles. And three seepage modes of bubble–slurry-conditioned sand were innovatively defined, and the occurrence conditions of the three seepage modes were analyzed according to the permeability coefficient of sand, initial dynamic shear force of bubble–slurry, and hydraulic gradient.

关键词： EPB shield     bubble–slurry     soil conditioning     stability     permeability    

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Coulomb-type solutions for passive earth pressure with steady seepage

WANG Junjie, CHAI Hejun, LIN Xin, XU Jiamei

《结构与土木工程前沿（英文）》 2008年 第2卷 第1期   页码 56-66 doi: 10.1007/s11709-008-0001-2

摘要： Present paper deals with the computing of passive earth pressure acting on the vertical rigid retaining wall supporting the soil mass subjected to water seepage. The basic assumptions of Coulomb’s theory and the 2-dimensional steady flow function are used. Three Coulomb-type solutions for the passive earth pressures are presented for the walls provided with three different drainage systems respectively. Based on the general solutions, the variations of the critical inclination of the failure surface and the coefficient of passive earth pressure with increasing the effective friction angle of the soil mass, the soil/structure friction angle, and the water/soil unit weight ratio are discussed. Two tables with values of the coefficients of passive earth pressure for Cases 1 and 3 respectively are also presented.

关键词： function     coefficient     Coulomb-type     effective friction     different drainage    

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Experimental study on working parameters of earth pressure balance shield machine tunneling in soft ground

ZHU Hehua, LIAO Shaoming, XU Qianwei, ZHENG Qizhen

《结构与土木工程前沿（英文）》 2008年 第2卷 第4期   页码 350-358 doi: 10.1007/s11709-008-0051-5

摘要： Deep sedimentary deposits of soft clays are widely distributed in coastal areas as well as many interior major cities in China. In order to study the stratum adaptability of earth pressure balance (EPB) shield machine tunneling in such types of soft ground, model tests of tunneling excavation, using the running tunnel of the Shanghai Metro Line M8 as a background, are carried out with different over burden ratios, opening rates of cutter head, driving speeds and rotation speeds of screw conveyor. Based on the test results, the interrelationships between chamber pressure and mucking efficiency, mucking rate and driving speed, thrust force and torque are obtained. The influences of tunnel depth, opening rate of cutter head and driving speed on thrust force and torque are revealed. Such findings can not only facilitate establishing relationships between shield working parameters and soil properties, but also serve as a guide for the design and construction of shield tunnel in soft ground.

关键词： construction     different     coastal     conveyor     excavation    

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Identification of abnormal operating conditions and intelligent decision system

Xiuliang LI, Junjie JIANG, Hongye SU, Jian CHU

《机械工程前沿（英文）》 2011年 第6卷 第4期   页码 456-462 doi: 10.1007/s11465-011-0224-0

摘要：

In earth pressure balance (EPB) shield construction, the “plastic flow state” is difficult to form using the soil dug in the capsule because it can cause three abnormal operating conditions, including occlusion, caking in the capsule, and spewing at the outlet of the dump device. These abnormal operating conditions can, in turn, trigger failure in tunneling, cutter-device damage, and even catastrophic incidents, such as ground settlement. This present paper effectively integrates the mechanism of abnormal operating conditions and knowledge of soil conditioning, and establishes a uniform model of identifying abnormal conditions and intelligent decision support system based on the belief rule-base system. The model maximizes knowledge in improving the soil, construction experience, and data to optimize the model online. Finally, a numerical simulation with specific construction data is presented to illustrate the effectiveness of the algorithm.

关键词： earth pressure balance (EPB) shield machine     soil pressure cabin     abnormal operating condition     belief rule-base system    

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高压多晶X射线衍射方法的发展及其在地球深部研究中的应用 Review

张莉, 苑洪胜, 孟悦, 毛河光

《工程（英文）》 2019年 第5卷 第3期   页码 441-447 doi: 10.1016/j.eng.2019.02.004

摘要：

下地幔占地球体积一半以上。在高温高压下对下地幔真实组分所开展的矿物学和岩石学实验是了解深部地幔演化过程的必要途径。激光加热的金刚石对顶压砧（laser-heated diamond anvil cell, LHDAC）是开展这类高温高压实验最常用的工具，实验产物通常包括从上百纳米到数微米尺寸不一的大量晶粒所组成的多相集合体。这些下地幔相的晶体结构往往不能在卸压后保存下来，因此必须对它们进行原位表征。相对于同步辐射光源设备中可用的聚焦X射线光斑尺寸（3~5 μm），晶粒尺寸要小一个量级，所得到的X射线衍射（X-ray diffraction, XRD）图谱通常显示为衍射斑点和衍射环的混合。由于多相衍射峰重叠严重，粉晶X射线衍射法无法对新相和弱相进行鉴定，因此采用传统XRD技术测定高温高压下多相混合物非常困难。我们最近在高压研究中所发展的同步辐射多晶X射线衍射法可以通过测定多相组合中成千上百个晶粒各自的晶面取向，使多相体系中单晶的指标化成为可能。一旦完成指标化，多晶混合物中的每一个晶粒都可以看作是单晶。因此，我们可以同时确定多相体系中新相和弱相的晶体结构。随着这一新方法的发展，我们开辟了深下地幔高温高压条件下的结晶学新领域。本文阐述了多相体系研究中的关键技术挑战，并通过高压多相X射线衍射法的成功应用实例，论证了该方法的独特能力。

关键词： 高压     同步辐射X射线     多晶     金刚石对顶压砧     矿物学     岩石学     地球内部    

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Solutions for a completely saturated porous elastic solid with impeded boundaries

CHEN Yunmin, LING Daosheng, ZHU Bin, CHENG Zehai

《结构与土木工程前沿（英文）》 2007年 第1卷 第3期   页码 322-328 doi: 10.1007/s11709-007-0042-y

摘要： Analytical solutions are presented for the consolidation of a semi-infinite stratum and a finite soil layer with an impeding layer located on the surface subjected to a vertical point loading. The Laplace transform and the Hankel transform are used with respect to time and the radial coordinate, respectively. Solutions of other distributed loadings, including the circular loading, can be easily obtained by integrating those of the point loading. The consolidation degree, excess pore water pressure, vertical total stress, and the shear stress of the consolidating layer are analyzed in this study. The consolidation rate decreases with the increase in the thickness of the impeding layer. Stresses of the consolidating layer vary during the consolidation due to the coupling of the excess pore water dissipation and the soil skeleton deformation. Further, the Mandel-Cryer effect is also analyzed in this study.

关键词： coupling     vertical     pressure     excess     distributed    

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The effect of texture and irrigation on the soil moisture vertical-temporal variability in an urban artificial

Xiaofeng ZHANG,Xu ZHANG,Guanghe LI

《环境科学与工程前沿（英文）》 2015年 第9卷 第2期   页码 269-278 doi: 10.1007/s11783-014-0672-y

摘要： Soil moisture variability in natural landscapes has been widely studied; however, less attention has been paid to its variability in the urban landscapes with respect to the possible influence of texture stratification and irrigation management. Therefore, a case study was carried out in the Beijing Olympic Forest Park to continuously monitor the soil in three typical profiles from 26 April to 11 November 2010. The texture stratification significantly affected the vertical distribution of moisture in the non-irrigated profile where moisture was mostly below field capacity. In the profile where irrigation was sufficient to maintain moisture above field capacity, gravity flow led to increased moisture with depth and thus eliminated the influence of texture. In the non-irrigated sites, the upper layer (above 80 cm) exhibited long-term moisture persistence with the time scale approximating the average rainfall interval. However, a coarse-textured layer weakened the influence of rainfall, and a fine-textured layer weakened the influence of evapotranspiration, both of which resulted in random noise-like moisture series in the deeper layers. At the irrigated site, frequent irrigation neutralized the influence of evapotranspiration in the upper layer (above 60 cm) and overshadowed the influence of rainfall in the deeper layer. As a result, the moisture level in the upper layer also behaved as a random noise-like series; whereas due to deep transpiration, the moisture of the deep layer had a persistence time-scale longer than a month, consistent with characteristic time-scales found for deep transpiration.

关键词： moisture vertical distribution     moisture temporal variation     texture stratification     irrigation     meteorological forcing     urban landscape    

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锚碇沉井基础施工期安全监控技术

冯兆祥,王锦国,王建

《中国工程科学》 2010年 第12卷 第4期   页码 68-72

摘要：

针对泰州大桥南锚沉井基础的结构特点和施工方法，设计了施工安全监控方案。施工期监测成果分析表明：沉井下沉初期沉井底部刃脚附近水平方向的拉应力较大，将此项物理量作为下沉的控制指标，有效指导了沉井施工；侧壁土压力分布随入土深度呈先增加后减小规律。

关键词： 沉井     控制指标     下沉     侧壁土压力    

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DX桩桩周土应力场分布的模型试验研究

唐松涛,陈立宏,袁希雨

《中国工程科学》 2012年 第14卷 第1期   页码 105-112

摘要：

通过室内小比尺的模型试验，可以进一步为确定DX桩沉降计算公式提供必要的依据。在小型模型试验箱中，通过采用杠杆加砝码的装置对22 mm桩径的DX桩在砂土中进行研究，测定单桩的桩顶荷载-桩顶位移曲线，确定承载力，并与相同情况下的直孔桩进行对比；同时，利用微型土压力盒测定土中应力变化，研究荷载在土中的传递规律。试验结果表明，DX桩的承载力及沉降特性明显优于直孔桩；承力盘在上部和下部时，DX桩尽管承载力相差不大，但是盘在下部时会增大桩端附近土体的应力；两个承力盘的DX桩，两盘受力比较一致，且盘受力的影响范围，在竖

关键词： DX桩     土压力盒     应力量测    

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Effect of earth reinforcement, soil properties and wall properties on bridge MSE walls

《结构与土木工程前沿（英文）》 2021年 第15卷 第5期   页码 1209-1221 doi: 10.1007/s11709-021-0764-2

摘要： Mechanically stabilized earth (MSE) retaining walls are popular for highway bridge structures. They have precast concrete panels attached to earth reinforcement. The panels are designed to have some lateral movement. However, in some cases, excessive movement and even complete dislocation of the panels have been observed. In this study, 3-D numerical modeling involving an existing MSE wall was undertaken to investigate various wall parameters. The effects of pore pressure, soil cohesion, earth reinforcement type and length, breakage/slippage of reinforcement and concrete strength, were examined. Results showed that the wall movement is affected by soil pore pressure and reinforcement integrity and length, and unaffected by concrete strength. Soil cohesion has a minor effect, while the movement increased by 13–20 mm for flexible geogrid reinforced walls compared with the steel grid walls. The steel grid stresses were below yielding, while the geogrid experienced significant stresses without rupture. Geogrid reinforcement may be used taking account of slippage resistance and wall movement. If steel grid is used, non-cohesive soil is recommended to minimize corrosion. Proper soil drainage is important for control of pore pressure.

关键词： mechanically stabilized earth walls     precast concrete panels     backfill soil     finite element modeling     earth reinforcement    

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Reliability analysis of the control system of large-scale vertical mixing equipment

YANG Mingjin, LI Xiwen, LI Shaoping, YANG Shuzi

《机械工程前沿（英文）》 2008年 第3卷 第2期   页码 133-138 doi: 10.1007/s11465-008-0037-y

摘要： The control system of vertical mixing equipment is a concentrate distributed monitoring system (CDMS). A reliability analysis model was built and its analysis was conducted based on reliability modeling theories such as the graph theory, Markov process, and redundancy theory. Analysis and operational results show that the control system can meet all technical requirements for high energy composite solid propellant manufacturing. The reliability performance of the control system can be considerably improved by adopting a control strategy combined with the hot spared redundancy of the primary system and the cold spared redundancy of the emergent one. The reliability performance of the control system can be also improved by adopting the redundancy strategy or improving the quality of each component and cable of the system.

关键词： composite     redundancy     monitoring     vertical     technical    

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Performance of vertical axis water turbine with eye-shaped baffle for pico hydropower

Zhuohuan HU, Dongcheng WANG, Wei LU, Jian CHEN, Yuwen ZHANG

《能源前沿（英文）》 2022年 第16卷 第4期   页码 683-696 doi: 10.1007/s11708-020-0689-9

摘要： A series of inline pico hydropower systems, which could be used in confined space, especially for water distribution networks (WDNs), was designed and investigated. The turbine with an eye-shaped vertical water baffle was developed to evaluate the hydraulic performance. A three-dimensional dynamic mesh was employed and the inlet velocity was considered as the inlet boundary condition, whereas the outlet boundary was set as the outflow. Then, numerical simulations were conducted and the standard turbulence model was found to be the best capable of predicting flow features through the comparison with the experimental results. The effects of the opening diameter of the water baffle and installation angle of the rotor on the flow field in the turbine were investigated. The results suggested that the water baffle opening at = 30 mm and the rotor at a 52° angle could achieve the highest efficiency of 5.93%. The proper eye-shaped baffle not only accelerates the fluid flow and generates positive hydrodynamic torque, but also eliminates the flow separation. The scheme proposed in this paper can be exploited for practical applications in the water pipelines at various conditions and power requirements.

关键词： vertical axis water turbine     eye-shaped     vertical water baffle     pico hydropower    

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标题 作者 时间 类型 操作

Experimental study on concrete box culverts in trenches

Baoguo CHEN, Junjie ZHENG, Jie HAN

期刊论文

Deviation correction strategy for the earth pressure balance shield based on shield–soil interactions

期刊论文

Upper bound solution to seismic active earth pressure of submerged backfill subjected to partial drainage

期刊论文

Experimental study on the stratum applicability and mechanisms of bubble–slurry for earth pressure balance

期刊论文

Coulomb-type solutions for passive earth pressure with steady seepage

WANG Junjie, CHAI Hejun, LIN Xin, XU Jiamei

期刊论文

Experimental study on working parameters of earth pressure balance shield machine tunneling in soft ground

ZHU Hehua, LIAO Shaoming, XU Qianwei, ZHENG Qizhen

期刊论文

Identification of abnormal operating conditions and intelligent decision system

Xiuliang LI, Junjie JIANG, Hongye SU, Jian CHU

期刊论文

高压多晶X射线衍射方法的发展及其在地球深部研究中的应用

张莉, 苑洪胜, 孟悦, 毛河光

期刊论文

Solutions for a completely saturated porous elastic solid with impeded boundaries

CHEN Yunmin, LING Daosheng, ZHU Bin, CHENG Zehai

期刊论文

The effect of texture and irrigation on the soil moisture vertical-temporal variability in an urban artificial

Xiaofeng ZHANG,Xu ZHANG,Guanghe LI

期刊论文

锚碇沉井基础施工期安全监控技术

冯兆祥,王锦国,王建

期刊论文

DX桩桩周土应力场分布的模型试验研究

唐松涛,陈立宏,袁希雨

期刊论文

Effect of earth reinforcement, soil properties and wall properties on bridge MSE walls

期刊论文

Reliability analysis of the control system of large-scale vertical mixing equipment

YANG Mingjin, LI Xiwen, LI Shaoping, YANG Shuzi

期刊论文

Performance of vertical axis water turbine with eye-shaped baffle for pico hydropower

Zhuohuan HU, Dongcheng WANG, Wei LU, Jian CHEN, Yuwen ZHANG

期刊论文