基于长方体盒型的异型纸盒曲面及曲拱结构变换

对多种常见纸包装曲面及曲拱结构设计进行了调查统计,讨论了3种基于长方体盒型的异型纸盒曲面及曲拱结构变换方式,并给出了由造型设计尺寸来计算其平面展开尺寸的必要参数,得出了适用于这些变换方式下的尺寸计算公式,有利于曲拱及曲面结构的计算机辅助设计算法的发展。

无筋拱肋双曲拱承载能力评定方法

以某无筋拱肋双曲拱桥为工程背景,通过技术状况检查和荷载试验确定桥梁截面检验系数。分别采用旧桥承载能力评定规程及考虑拱实际开裂的方法,对无筋拱肋双曲拱的承载能力进行评定,并对评定结果进行了对比分析。结果表明:考虑拱实际开裂的方法评定无筋拱肋双曲拱桥的承载力较按评定规程方法评定的承载能力低,评定结果更符合实际。

混凝土双曲拱桥病害与加固研究

结合结构特点对混凝土双曲拱桥的常见病害进行深入的病因分析与研究,同时针对维修加固及改建方法进行详细阐述,对混凝土双曲拱桥的病害防治具有积极意义。

汉语声调的时长与汉语声调曲拱、音高的相关性讨论

通过对近十几年来用语音实验的手段,研究现代汉语声调的研究材料进行统计分析,考察汉语声调的时长特征与汉语声调的曲拱和音高特征的相关性。

汉语声调的时长与汉语声调曲拱、音高的相关性讨论

通过对近十几年来用语音实验的手段研究现代汉语声调的研究材料进行统计分析,考察汉语声调的时长特征与汉语声调的曲拱和音高特征的相关性。

声调感知的三个基本问题——载调单位、北京话上声的本质特征和曲拱调的阶段性

本文将北京话的16个单字音作为实验语料,通过改变音高和时长参数重新合成刺激音。以此为基础,通过三个感知实验(①改变单字音声调曲线前100ms的音高;②上声调下降段改为低平调;③声调曲线前100ms之后的音高等分合成),系统考察了10位北京人的听感表现。结果表明:改变单字音声调曲线前100ms的音高,不会对声调曲线的调类感知产生明显影响;北京话上声的开头下降段改为平调也不会影响到感知,再次证明了北京话上声的本质特征是“低平调”;上升调和下降调改换为几个音高阶段的组合后被听成原调的比率仍然较高,合成字音的音高分段数量越多,自然度就越高。

混凝土顶升法施工技术研究

结合抚顺皇家海洋世界跨线桥110m提篮式双曲钢管混凝土拱施工,介绍了顶升法泵送混凝土的施工和质量控制方法;并依据混凝土顶升的施工原理、顶升压力,分析了影响因素,改进了混凝土配合比;采取设置止回装置和排气溢流孔等方法,解决了钢管拱混凝土一次顶升的难题。

基于语音实验的湖南茶陵城关镇方言声调研究

采用语音实验的方法研究了茶陵城关镇方言的单字调。研究认为,今茶陵城关镇方言有5个单字调,古入声今已归阴去,各调类调值分别是:阴平341、阳平524、上声51、阴去43、阳去45。研究还认为:声调的时长与声调调型尤其是与声调的曲拱密切相关。

论英语语调结构与信息结构的关系

英语语调结构和信息结构是独立于音系学、句法学和语义学之外的两个相互关联的语法层面,语调结构在很大程度上影响信息结构的构成,反之亦然。本文从语调结构构成的三要素(语调曲拱、断句和凸显)入手阐述了语调结构的功能,并在此基础上进一步探讨了语调结构与信息结构之间的相互关系。

普通话声调调素的音高实验

通过实验方法研究普通话单字调调素的音高,得出调素的音区特征和曲拱特征。实验发现:普通话声调包含三个调素,分别是高音区调素H、中音区调素M和低音区调素L,普通话四个声调用调素表示为阴平HHH、阳平MHH、上声LLH、去声HML。调素有曲拱,每个调素都是平拱,各声调的曲拱样态由平拱组合而成。

在野建筑学 五号宅营造记

宁波慈溪五号宅的设计用了将近2年多时间,从绘制柯宅的初稿时就开始了这个设计过程,建筑师试图根据现实的施工条件去回应一直思考的一些问题。五号宅是曲线结构系列里的第一个住宅,这个系列使得建筑师的思考逐步清晰——如何在当今建筑主体实践以及教育都堕入精致的产品主义圈套中时,还能保持一份在野建筑学的野味及清气。

文革桥维修加固工艺优化及安全性验算

对湖南省澧县文革桥的结构损坏情况进行的分析,阐述了维修加固的设计原则及有关施工工艺优化方案,通过对施工工艺安全性进行验算,表明工艺优化方案合理可行。

新城大桥钢管砼拱桥成桥施工技术探讨

新城大桥全桥长1 270m,引桥为6跨一联30mT梁,主跨为中承式钢管砼提蓝拱,边跨为变截面钢筋砼双曲拱。主要介绍主桥部分施工工艺及主要技术方案等情况。

Seismic Deformation and Seismic Resistance Analysis of Shapai Roller Compacted Concrete Arch Dam Based on Field Monitoring and Dynamic Finite Element Method

Shapai Roller Compacted Concrete(RCC) Arch Dam is the highest RCC arch dam of the 20th century in the world with a maximum height of 132m,and it is the only concrete arch dam near the epicentre of Wenchuan earthquake on May 12th,2008.The seismic damage to the dam and the resistance of the dam has drawn great attention.This paper analyzed the response and resistance of the dam to the seismic wave using numerical simulations with comparison to the monitored data.The field investigation after the earthquake and analysis of insitu data record showed that there was only little variation in the opening size at the dam and foundation interface,transverse joints and inducing joints before and after the earthquake.The overall stability of the dam abutment resistance body was quite good except a little relaxation was observed.The results of the dynamic finite element method(FEM) showed that the sizes of the openings obtained from the numerical modeling are comparable with the monitored values,and the change of the opening size is in millimeter range.This study revealed that Shapai arch dam exhibited high seismic resistance and overload capacity in the Wenchuan earthquake event.The comparison of the monitored and simulated results showed that the numerical method applied in this paper well simulated the seismic response of the dam.The method could be useful in the future application on the safety evaluation of RCC dams.

Mechanical response of continuously reinforced concrete pavement on foam concrete interlayer for two-way curved arch bridge

In order to research the mechanical response of continuously reinforced concrete pavement on foam concrete interlayer for a two-way curved arch bridge, the elliptical vehicle load is translated into the rectangular load based on the equivalence method. Then, a three-dimensional finite element model of the whole bridge is established. The reliability of the model is verified. Additionally, the mechanical response of continuously reinforced concrete pavement under vehicle loading is analyzed. Finally, the most unfavorable loading conditions of tensile stress, shear stress and vertical displacement are determined. The results show that the most unfavorable loading condition of tensile stress, which is at the bottom of continuously reinforced concrete pavement on the two-way curved arch bridge, is changed compared with that on homogeneous foundation. The most unfavorable loading condition of shear stress at the top is also changed. However, the most unfavorable loading condition of vertical displacement remains unchanged. The tensile stress at the bottom of about 1/4 span of the longitudinal joint, the shear stress at the top of intersection of transverse and longitudinal joint, together with the vertical displacement at the central part of longitudinal joint, are taken as design indices during the structural design of continuously reinforced concrete pavement on the two-way curved arch bridge. The results are helpful for the design of continuously reinforced concrete pavement on unequal- thickness base for the two-way curved arch bridge.

The Stability Study of Globe Transportation Center of Beijing Capital International Airport

The stability of long span steel arch structure of globe transportation center (GTC) in the Beijing Capital International Airport was studied. Different objective models such as single arch model, composite arch model and global structural model were introduced to analyze the structural stability by means of the finite element technique. The eigen buckling factor of the steel arch structure was analyzed. The geometrical nonlinearity, elastic-plastic nonlinearity and initial imperfection were taken into account in the investigation of the structural buckling, and the nonlinearity reduction factors for the steel arch structure were discussed. The effects of geometrical nonlinearity and initial imperfection on the structural buckling are light while the effect of material nonlinearity is quite remarkable. For a single steel arch, the dominant buckling mode occurs in out-of-plane of arch structure. The out-of-plane buckling factor of the composite steel arch is greater than that of the single steel arch while the in-plane buckling factor of the former is somewhat less than that of the latter. Moreover, the webs near the steel arch feet have the lowest local buckling level and the local buckling is more serious than the global buckling for the global structure.

Cyclic behavior test of a new double-arch steel gate

A new double-arch structure for the gate used as tidal barrage and sluice was adopted in Caoe River Dam in China. It was a spatial structure made up of the right arch, the invert arch, the chord, etc., and was designed to bear bilateral loads. To research the cyclic behavior of the new double-arch structure, a scale-model cyclic test was conducted. First, the test setup and test method were presented in detail, and according to the test results, the cyclic behavior and failure characteristics of this structure were discussed. Then by analyzing the test cyclic envelope curve, it was found the curve was divided into three stages: the elastic stage, the local plastic stage and the failure stage at the local yield point and structural yield point. The gate model has local yield strength and structural yield strength, with both their values being bigger than that of the designing load. Therefore, the gate is safe enough for the projects. At last, dynamic property of the gate was analyzed considering additional mass of the water. It was found that the tidal bore shock would not cause resonance vibration of the gate.

In-Plane Creep Buckling of Concrete-Filled Steel Tubular Arches

The creep-induced deformation of the arch rib of concrete-filled steel tubular （CFST） arches under a sustained load can increase the bending moment, which may lead to earlier stability failure called creep buckling. To investigate the influences of concrete creep on the buckling strength of arches, a theoretical analysis for the creep buckling of CFST circular arches under distributed radial load is performed. The simplified Arutyunyan-Maslov （AM） creep law is used to model the creep behavior of concrete core, and the creep integral operator is introduced. The analytical solutions of the time-dependent buckling strength under the sustained load are achieved and compared with the existing formula based on the age-adjusted effective modulus method （AEMM）. Then the solutions are used to determine the influences of the steel ratio and the first loading age on the creep buckling of CFST arches. The results show that the analytical solutions are of good accuracy and applicability. For CFST arches, the steel ratio and the first loading age have significant influences on creep buckling. An approximate log-linear relationship between the decreased degrees of the creep buckling strength and the first loading age is found. For the commonly used parameters, the maximum loss of the buckling strength induced bv concrete creen is close to 40%

疑问和陈述语气与边界调

从语料的听辨试验结果看到,疑问在离开上下文后有不同强度。本文用声学数据论述关于普通话回声问边界调的以下看法:疑问语气和陈述语气由短语的边界音节携带,汉语有边界调;边界调为重音节时,疑问 F_0曲拱的斜率比陈述的大,或音阶比陈述的高,或者同时满足这两个条件;疑问的边界调 F_0曲拱,无论阴平、阳平、上声和去声,都保持其单字调调型不变;疑问边界调的时长比其陈述的长,但疑问及陈述的边界调时长都不一定比其前音节的长。合成实验结果证明,疑问语气和陈述语气的区分只能来自边界调。辨认测验结果证实,F_0曲拱斜率和音阶是边界调的声学关联物,具有变换语气作用,疑问的边界调时长是伴随的。本文指出,短语末的边界调为轻声音节时,其声学关联物仍是 F_0曲拱的斜率和音阶,疑问的时长总比陈述的长。我们认为,疑问的"高"是相对于陈述的而言,它的"高"是因为其边界调F_0曲拱的斜率相对大和(或)音阶相对高。疑问的边界调要比陈述的"重"。