“大筋緛短,小筋弛长”与运动神经元病相关性初探

“大筋緛短,小筋弛长”系外感湿邪,湿酿化热,煎熬阴津,筋脉失养所致。历代医家对大筋和小筋所指部位存在疑议,亦未点明緛短及弛长的具体表现。笔者结合现代疾病,从病因病机、临床表现、辨治方药及其机制角度对“大筋緛短,小筋弛长”与运动神经元病(MND)的相关性进行探究,发现“大筋緛短,小筋弛长”或为MND最早的文献记载。大筋緛短系上运动神经元损伤,表现为肌张力增高、腱反射亢进等,以整个肢体为主,呈痉挛性;小筋弛长系下运动神经元损伤,表现为肌肉萎缩、肌张力降低、腱反射减弱甚或消失等,以肌群为主,呈迟缓性。“大筋緛短,小筋弛长”既可共同亦可独立出现。

加筋土桥台筋带最大拉力试验研究

通过室内大比例模型试验,研究自重作用下加筋土桥台的最大筋带拉力的变化规律。加筋土桥台最大筋带拉力作用线的上部是离面板约为墙高0.2倍左右距离的垂直顶面的直线,下部渐渐向面板靠拢,近似为一条以面板顶点为极点的对数螺旋线。最大筋带拉力上部(垂线段)较大,下部渐小。基于试验结果与现场实测结果,提出最大筋带拉力与对应最大筋带拉力作用线距面板的水平距离成正比的计算模型。与其他理论及实验结果的比较表明,该计算模型对最大筋带拉力的预测能有效地反映刚性面板影响,能更准确地预测实际的最大筋带拉力,其预测值与实测结果的误差只有14%,而其他理论预测值与实测结果的误差均大于50%。

双面加筋路堤的地震动力响应分析

双面加筋路堤作为加筋土挡土墙的一种衍生结构,沿袭了加筋土挡土墙优良的抗震性能,被广泛应用于道路建设工程,然而国内外关于双面加筋路堤的抗震设计还不够完善,采用的基于极限平衡法的抗震设计仍存在诸多问题。采用基于PLAXIS软件的有限元分析方法,对双面加筋路堤进行了较为全面的动力特性分析,结果表明,地震作用下双面加筋路堤的各层筋材最大内力分布、单侧面板侧移形式及路面沉降形式同单一的加筋土挡土墙表现形式相似;通过对不同宽高比结构筋材内力的分析得出,在地震作用下,加筋区及非加筋区之间存在第二潜在破裂面发育的可能。基于单自由度强迫振动理论及数值分析结果,建立了整体最大筋材内力与地震动及结构参数的关系。

膝部“大筋”“小筋”之我见

曲泉定位与取穴法,《灵枢·本输》曰:“辅骨之下,大筋之上也,屈膝而得之”,《黄帝明堂经》[1]192补充“小筋下陷者中”。对于阴谷,《灵枢·本输》曰:“辅骨之后,大筋之下,小筋之上也,按之应手,屈膝而得之”,《黄帝明堂经》[1]203表述与此类同。历代多沿用,此示古人以膝部“辅骨”“大筋”“小筋”为定取二穴的重要标志。“辅骨”为“挟膝两侧之骨”[2],此处专指内辅骨,现代一般认作股骨下端的内侧髁与胫骨上端的内侧髁组成的骨突[3-4],但“大筋”“小筋”鲜有完备解释。本文旨在探讨古代“大筋”“小筋”对应的现代解剖学膝部相关结构。

阴谷穴与曲泉穴定位探讨

[目的]厘清阴谷与曲泉两穴的准确定位。[方法]查阅相关古籍、教材、著作及文献,比较分析古籍原文中关键词“膝内辅骨”“大筋”“小筋”“之下”“之上”的含义,并从经脉循行规律、局部解剖特点、临床实际运用方面,考证各种定位的合理性。[结果]有别于现代文献,不同古籍文献对两穴的位置记载较统一,“膝内辅骨”指股骨内上髁和胫骨内侧髁两部分,“大筋”“小筋”分别指半腱肌和半膜肌,“之下”“之上”分别指外侧和内侧。当阴谷穴定位“在膝后区,腘横纹上,半腱肌肌腱外侧缘”,曲泉穴定位在“膝部,腘横纹内侧端,半腱肌内缘凹陷中”时,两穴的定位既符合经典古籍描述,又符合经脉循行规律、局部解剖特点和临床实际运用,并且两穴定位之间相互印证,没有矛盾。[结论]阴谷与曲泉的上述定位较其他定位更为合理,更有利于指导临床运用。

滚装码头护舷布置与优化

滚装码头是与靠泊船舶密切相关的一种码头类型,滚装船吃水浅,上层结构高大,舷侧设置有用以保护船身的凸出的钢质护舷材,易造成防冲板及码头前沿护轮坎等损坏,大于3000 GT的大中型滚装码头往往布置有辅助靠泊平台,采用侧靠导向、正向丁靠方式靠泊。本文针对滚装船特有的船型特点及靠泊方式进行了分析研究,以湛江港徐闻港区南山作业区客货滚装码头0#泊位为实例,针对性地提出了与之相适应的护舷布置方案,为类似工程提供参考借鉴。

Properties and calculation of normal section bearing capacity of RC flexural beam with skin textile reinforcement

In order to overcome the wide crack of ordinary reinforced concrete (RC) at service stage which affects the service performance and durability of structures,a kind of concrete structure with skin textile reinforcement is proposed,namely a part of concrete cover of RC members is replaced by textile reinforced concrete (TRC).The flexural experimental results indicate that when the reinforcement ratios of steel bars are constant,compared with control beams,the average value of crack loads of the beams,whose reinforcement ratios of textile are 0.018%,0.036% and 0.055%,increases by 15.5%,20.4% and 31.1%,respectively,the average value of yield loads respectively increases by 12.5%,19.9% and 21.1% and the average value of ultimate loads respectively increases by 8.5%,26.0% and 44.0%,respectively.Considerable reduction in cracks width and spacing is observed for specimens with a TRC layer,and when the beams yield,the maximum crack width of the beam with textile stuck no sand and the beam with textile stuck sand is reduced by around 60% and 70%,respectively.Surface treatment of textile and mixing polypropylene fiber into fine grained concrete contribute to enhance the service performance of the flexural element.Embedding U-shaped hoop has almost no effect on the control of the crack width.Finally,the calculation method of ultimate bearing capacity of this flexural component with TRC layer was presented.Comparison between the calculated and the experimental values reveals satisfactory agreement,and the maximum error is no more than 6%.

Analysis of Thermal Bridge Impact in a Hotel Building for the Eight Brazilian Bioclimatic Zones

This article aims to present an analysis of the influence of thermal bridges on reinforced concrete structural systems regarding energy performance of the envelope of a commercial building located in the bioclimatic zones 1 to 8 in Brazil, using computer simulation. The method used to achieve this goal includes the following steps： （1） definition and configuration of the base case; （2） definition and configuration of the reference model; （3） optimization of energy modeling; （4） energy modeling and comparison of consumption between the base case and the reference model. Main results showed that thermal bridges in reinforced concrete interfere on the building＇s energy performance and that the impact is related to the WWR （window-to-wall ratio） on the building. For hotel buildings with WWR from 30% to 45%, thermal bridges imply a decrease in estimated consumption, which can reach 10%, depending on the bioclimatic zone. For 60% WWR, the non-consideration of thermal bridges can represent up to 5% of increase in estimated consumption, depending on the Brazilian bioclimatic zone.

Tensile bond anchorage properties of Australian 500N steel bars in concrete

In order to investigate the tensile bond anchorage properties of Australian 500N steel bars in concrete, 111 pullout tests were conducted. The precise bond slip values have been gained by using the laser displacement sensor with high resolution, including the complete bond-slip curves. How the main anchorage factors such as concrete strength, bar diameter （8, I0, 12, 16, 20, 24, 28, 32 and 36 mm） the concrete covered, embedded length and transverse reinforcement influencing the bond anchorage properties was studied under tensile condition. The process of the tensile force-slip failure for Australian 500N reinforcing steel can be divided into five stages： elastic stage, local slip stage, slip in ascent stage, slip in descent stage and remnant stage. The formula for calculating the tensile bond strength of Australian 500N reinforcing bar in concrete was proposed according to the test results, including the consistent model for tensile bond-slip relationship.

Construction of a Butterfly Web Bridge

A new type of bridge called ＂butterfly web bridge＂ is under construction in Japan. In a butterfly web bridge, the butterfly-shaped web forms a structure that exhibits behavior similar to a double Warren truss. The 80 MPa concrete is used for the butterfly web which has a precast plate with a thickness of 150 mm. As butterfly web is a concrete material, reinforcement provided by prestressing tendons is needed on the tension side. Moreover, the 150 mm plate has no re-bars but is reinforced by steel fibers. This bridge, named Takubogawa Bridge, is a highway bridge and has 10 spans including the 87.5 m maximum span length. Takubogawa Bridge is constructed by flee cantilevering method. The butterfly web enables the construction speed of cantilevering to be advanced about 50% compared with conventional cast-in-situ method and can meet the requirement of light weight and low maintenance.

Comparative Analysis of High-Rise Reinforced Concrete Structures According to International Seismic Design Codes

The field of earthquake engineering and seismology is of great importance to structural engineers around the world. The location, size and consequences of an earthquake are variable depending on several conditions. Surface conditions, boundary/fault type, distance from the boundary and hypocenter are all elements that dictate the outcome of a seismic event. The paper presents a comparison of seismic provisions of two seismic design codes--EC8 （Eurocode 8） and IBC （International Building Code） 2006, to a high-rise reinforced concrete building. The building is irregular and composes of 20 floors. The equivalent lateral force analysis was performed using the well-known structure program--ETABS （Extended 3D Analysis of Building Systems）. Based on the analysis results （inter-storey index, global damage index, storey displacement, inter-storey drift ratio and base shear）, EC8 was found to be conservative when compared with IBC 2006. The conclusion is that for the design and analysis of high-rise reinforced concrete buildings with certain irregularity, EC8 provisions were considered to be conservative.

Design and construction of high and large span cast-in-place reinforced concrete cantilever flowering frame beam

The high and large span cast-in-place reinforced concrete cantilever structure of the office building of some court, which is located I-steel at the cantilever and used steel pipe scaffold as the support, has guaranteed the frame body and structure security by the frame body calculating, on-site test and reasonable construction order.

Interaction between Engineering Structures and Environment, Illustrated on the Examples of Bridges in Montenegro

The basic goal of this paper is to point out the importance of design shaping as well as the key parameter of the great interaction between the structure and natural environment. However, experiences confirm the fact that the most successful structures, the bridges also, have not got that attribute because of their grandiosity but per their great integration in the nature that is environment. Beside the basic function, that is the usage to man, their integrations in the environment greately enrich the ambience. The old stone bridges are mostly well integrated in the natural environment. In the period of large building, it did not take care of the parameters （the bridges of steel, concrete and prestressed concrete）, but great attention was paid to records referring to spans and complicated forms. The author thinks it is necessary to take care about integration of all building structures in the environment, especially bridges. As a good example of successful creation, simplicity of form, and especially good integration in the natural surroundings are three bridges from Montenegro, one of them is old stone bridge, others are reinforced-concrete and steel bridges.

经外奇穴二白穴统考

二白穴首载于《窦太师针经》,穴意:“二”为数词,意为一穴两处,“白”为可见的颜色,肺之色也,属秋季,其性沉降、肃杀、收敛。接收来自郄门之地部经气,以作收敛止痛之用。定位:在前臂前区,腕掌侧远端第一条实长横纹上4寸,桡侧腕屈肌腱的两侧;主治:痔疮,脱肛,痔漏或痛或痒或下血,里急后重等及肛肠类疾病术后疼痛;操作:针灸、推拿、针刀、穴位贴敷、揿针、埋线等。

Field study on performance of new technique of geosynthetic-reinforced and pile-supported embankment at bridge approach

Vehicle bumps at a bridge approach caused by the differential settlement between a bridge and an adjacent backfill embankment are one of the most difficult problems in geotechnical engineering. Large vehicle bumps make drivers uncomfortable and cause large impact loads on vehicles and the bridge abutment. A new ground-improvement technique called fixed-geosynthetic-reinforced and pile-supported embankment(FGT embankment) was developed and used to alleviate vehicle bumps at a trial bridge-approach site located in central China. To distribute the differential settlement between the bridge and adjacent backfill embankment over a long transition zone, the following three techniques were used at the trial bridge-approach site:(a) the FGT embankment,(b) conventional geosynthetic-reinforced and pile-supported embankment(CT embankment), and(c) geosynthetic-reinforced embankment without piles(GR embankment). The performance of all three techniques in the field trial was investigated by field measurements involving earth pressure cells, geosynthetic deformation sensors, and settlement gauges. The FGT and CT embankments exhibited better performance than the GR embankment. Compared with the CT embankment, the FGT embankment was more effective at ground improvement. At an elevation of 4.0 m from the base of the embankment, the pressures below the geosynthetic were smaller than those above the geosynthetic at the closest measurement point. The difference between the pressures between above and below the geosynthetic tended to increase with the embankment height.