Thermo-hydro-mechanical-air coupling finite element method and its application to multi-phase problems

In this paper, a finite element method （FEM）-based multi-phase problem based on a newly proposed thermal elastoplastic constitutive model for saturated/unsaturated geomaterial is discussed. A program of FEM named as SOFT, adopting unified field equations for thermo-hydro-mechanical-air （THMA） behavior of geomaterial and using finite element-finite difference （FE-FD） scheme for so/l-water-air three-phase coupling problem, is used in the numerical simulation. As an application of the newly proposed numerical method, two engineering problems, one for slope failure in unsaturated model ground and another for in situ heating test related to deep geological repository of high-level radioactive waste （HLRW）, are simulated. The model tests on slope failure in unsaturated Shirasu ground, carried out by Kitamura et al. （2007）, is simulated in the framework of soil-water-air three-phase coupling under the condition of constant temperature. While the in situ heating test reported by Munoz （2006） is simulated in the same framework under the conditions of variable temperature hut constant air pressure.

论合宪性推定之司法方法

合宪性推定的司法方法区别于一般法律的推定。合宪性推定方法为挑战制定法违宪的当事人设置了一种责任负担,要求其提出充足的证据来证明制定法"明显违宪",否则将推定该制定法合乎宪法。合宪性推定在很大程度上是法律问题,而不是纯粹的事实问题,虽然也离不开事实。合宪性推定在司法实践中同样具有特殊的消解疑难案件的功能。

比例原则的中国宪法规范基础新论——以宪法第33条为中心

要实现比例原则的司法适用,需首先为其在宪法文本中找到规范基础。比例原则的本质应是"公民与国家之间权利义务的对称性",由此提出并论证以中国宪法第33条为比例原则的规范基础。法院可在判决中,通过该条款进行合宪性法律解释,为运用比例原则说明理由。以此为起点,比例原则的司法适用还有待于推动进一步的宪政改革,明确比例原则的司法技术定位,以及案例指导制度、司法解释制度的跟进。

政治角色年龄资格设计引论

政府一旦确定了某种政治角色的年龄资格,就势必将公众划分为符合与不符合这一资格的两个部分。这意味着其中一部分将因此能不能获得承担此种政治角色从而增加收益或减少利益受损的机会。进言之,政治角色年龄资格的设计实际上体现的是政府在不同群体间对政治资源或利益的分配。在现代民主政制中,这无疑是涉及权利平等与公平的宪政价值能否实现的大事。由此,对政治角色年龄资格设计的方式及考量因素,进而对政治角色年龄资格设计的合宪性,必须给以足够的重视。

Finite Element Simulation of Flexible Roll Forming with Supplemented Material Data and the Experimental Verification

Flexible roll forming is a promising manufacturing method for the production of variable cross section products. Considering the large plastic strain in this forming process which is much larger than that of uniform deformation phase of uniaxial tensile test, the widely adopted method of simulating the forming processes with non-supplemented material data from uniaxial tensile test will certainly lead to large error. To reduce this error, the material data is supplemented based on three constitutive models. Then a finite element model of a six passes flexible roll forming process is established based on the supplemented material data and the original material data from the uniaxial tensile test. The flexible roll forming experiment of a B pillar reinforcing plate is carried out to verify the proposed method. Final cross section shapes of the experimental and the simulated results are compared. It is shown that the simulation calculated with supplemented material data based on Swift model agrees well with the experimental results, while the simulation based on original material data could not predict the actual deformation accurately. The results indicate that this material supplement method is reliable and indispensible, and the simulation model can well reflect the real metal forming process. Detailed analysis of the distribution and history of plastic strain at different positions are performed. A new material data supplement method is proposed to tackle the problem which is ignored in other roll forming simulations, and thus the forming process simulation accuracy can be greatly improved.

Characterization of transient groundwater flow through a high arch dam foundation during reservoir impounding

Numerous deep underground projects have been designed and constructed in China, which are beyond the current specifications in terms of scale and construction difficulty. The severe failure problems induced by high in situ stress, such as rockburst, spalling, damage of deep surrounding rocks, and timedependent damage, were observed during construction of these projects. To address these problems, the dynamic design method for deep hard rock tunnels is proposed based on the disintegration process of surrounding rocks using associated dynamic control theories and technologies. Seven steps are basically employed：（i） determination of design objective,（ii） characteristics of site, rock mass and project, and identification of constraint conditions,（iii） selection or development of global design strategy,（iv）determination of modeling method and software,（v） preliminary design,（vi） comprehensive integrated method and dynamic feedback analysis, and（vii） final design. This dynamic method was applied to the construction of the headrace tunnels at Jinping II hydropower station. The key technical issues encountered during the construction of deep hard rock tunnels, such as in situ stress distribution along the tunnels, mechanical properties and constitutive model of deep hard rocks, determination of mechanical parameters of surrounding rocks, stability evaluation of surrounding rocks, and optimization design of rock support and lining, have been adequately addressed. The proposed method and its application can provide guidance for deep underground projects characterized with similar geological conditions.

英美司法审查制度之比较

由于历史的原因,英美两国的司法审查制度存在着千丝万缕的联系,但是,宪政制度的不同,却也造成了它们之间的差异。这种差异从两国司法审查的范围、程度、方法以及起诉资格的限制等方面就可以看出。然而,随着世界范围内对人权保障的逐步加深,两国的司法审查制度也呈现出相同的发展趋势,那就是建立一套范围更广、程度更深、方法更统一、限制更少的司法审查制度。

First-order gradient damage theory

Taking the strain tensor, the scalar damage variable, and the damage gradient as the state variables of the Helmholtz free energy, the general expressions of the firstorder gradient damage constitutive equations are derived directly from the basic law of irreversible thermodynamics with the constitutive functional expansion method at the natural state. When the damage variable is equal to zero, the expressions can be simplified to the linear elastic constitutive equations. When the damage gradient vanishes, the expressions can be simplified to the classical damage constitutive equations based on the strain equivalence hypothesis. A one-dimensional problem is presented to indicate that the damage field changes from the non-periodic solutions to the spatial periodic-like solutions with stress increment. The peak value region develops a localization band. The onset mechanism of strain localization is proposed. Damage localization emerges after damage occurs for a short time. The width of the localization band is proportional to the internal characteristic length.

论合宪性解释规则的司法适用路径

合宪性解释规则包括单纯解释规则、冲突规则和保全规则。单纯解释规则与冲突规则在司法裁判中混淆适用的问题需要阐明“宪法何时出场”,而两者的界定也明确了合宪性解释作为独立解释方法的基本立场。合宪性解释保全规则与合宪性审查具有异质性,违宪疑虑作为宪法事实的客观存在导致了保全规则出现在司法裁判中的必然性。合宪性解释在不同涉宪情形下适用路径不同,其能够为推动宪法实施和合宪性审查的制度建构提供具体司法路径,与具体审查的程序衔接则赖于最高人民法院宪法解释请求权的启动。

他律型方法的立法运用与规范设置——以备案审查制度为例

他律型立法方法是立法机关审查地方立法的方法,是加强备案审查的结果,旨在维护我国法制统一。他律型立法方法在立法实践中针对不同的审查内容,分别设置了合宪性审查、合法性审查和合法规性审查三种审查模式。这三种审查模式共同构建起我国特色的复合审查体制。他律型立法方法的规范适用,应当遵循职权法定的规则,为不同他律主体提供明确的审查范围,同时也应当按照程序法定规则的指引,要求他律主体依法履行备案审查,实现法律体系内部的稳定、统一。

合宪性推定的正当性

合宪性推定是宪法审查中一种重要方法。其最初起源于美国,尔后逐渐被德国、日本、澳大利亚等法治国所采用。国内目前对于合宪性推定方法的认识尚有不足,在一定程度上影响了宪法审查制度的有效运作。对于合宪性推定方法的借鉴,不在于简单移植,重点在于从一般原理的角度来探求其所存在的正当性基础。从人权价值、规范体系、经济理性等多角度对合宪性推定的正当性进行论证,可发现合宪性推定是一种原理性的宪法方法,根基于宪法的最高性、法官的经济理性、人权的目的性、国家权力的手段性等。合宪性推定的正当性论证,在折射出目前宪法方法的贫瘠的同时,也有助于摆脱宪法文本浪漫主义的方法论困境,进而体现出宪法方法兼具政治与法律的特性。