查询词典 span roof

The top coal fracture is described distinctly under the condition of different roof span and mining technology parameters. Through orthogonal experiment of numerical simulation, the rational pretreatment span of hard roof is determined, and the rational working resistance of support is selected also. As a result: the hard roof is effectively controlled not only to protect the working face but also to promote the caving of hard top coal to increase the recovery ratio.

在有效控制坚硬顶板的基础上，利用数值模拟正交试验法，研究了采高、采放比、支架阻力、放煤步距等工艺参数对顶煤压裂效果的影响规律，从而对工作面工艺参数进行优化；并根据实验所得放煤方式对块体顶煤的适应性规律，选择&两硬&综放面的放煤工艺，从而形成了系统、完善的&两硬&条件综放工艺。

The trial results show that with the disposal of induced caving roof by presplitting blasting and induced caving roof blasting, about 17.8 m in thickness of rock cushion is successfully formed in the inferior abandoned stope, which can bring down the harm of dashing blast of an explosion caused by roof collapse; apparent run-through flaws arise between presplitting blasting holes, and controllable caving is formed in the roof, abrupt collapse of large area roof is prevented, the productional safe surroundings of underground mining is improved; eventually, the resources' reclamation rate is improved from about 70% to 84.6%, and the dilution rate is abated from 25%40% to below 15%, so efficiently withdrawing is actualized.

试验结果表明：采用预裂爆破与诱导崩顶爆破的方法，通过对顶板的诱导崩落处理，成功地在下方采空区形成了厚度为17.8 m左右的岩石缓冲垫层，有效地降低顶板冒落带来的冲击气浪危害；在预裂孔间产生明显的贯通裂隙，从而在顶板上形成诱导可控崩落，防止顶板大面积的突然垮落，改善地下开采安全生产环境；最终资源的回收率由70%左右提高到84.6%，贫化率由25%~40%降低到15%以下，实现了资源的高效回收。

And tonight is my first time on c-span, which is a channel i obviously always watch when i couldn"t stand the sensationalism and demagoguery of pbs and qvc. if i still couldn"t fall asleep after watching c-span, there is c-span 2 and c-span 3. thank you very much.

今晚是我第一次来到c-span频道，通常当我无法忍受pbs和qvc的鼓吹与煽动时我就会选择看你们的频道（pbs的节目以主观著称，qvc则是购物频道，说这段的时侯镜头给了下面人一个特写，莫非是这两个频道的老板？

The stretching influence on the near trusses should be considered when using the stretching-twice method, and the construction is hard to be controlled. The Harbin exhibition sports center with a 128m support span, attached to a deep design calculation of the super-large span prestress truss string structure, stretching once in tension bed method is brought forward for the bottom cable of the single truss string structure. From calculation research on the friction force between the tension bed and the truss string structure, the friction influence is considered for the displacement method of the middle of span, with the action of the fixed cable stress. This method, with vertical displacement of the middle of span as its main control target for prestress stretching, is successfully applied in the prestress stretching construction of the project.

二次张拉需考虑张拉对相邻桁架的影响，施工控制难度大，本文结合哈尔滨会展体育中心支座跨度128m的超大跨度预应力张弦桁架结构的深化设计计算，提出了单榀张弦桁架下弦拉索胎架一次张拉法施工方法，通过对张拉阶段胎架与张弦桁架间摩擦力的计算研究，定量索力下跨中位移法考虑摩擦力影响，以跨中竖向位移作为预应力张拉的主要控制指标，成功地完成了该工程预应力张拉施工。

So far,a limited number of research papers are related to dynamic response of long-span flexible roofs.Gymnasium roof is a special topic of long-span flexible roof structures,a-nd it is important to study on wind load and gust loading factor in the field of engineering and research.

目前国内外对大跨度柔性屋盖的风振响应研究很少，本文研究的体育馆屋盖结构的风荷载及风振系数作为大跨度柔性屋盖结构的一个专题，具有重要的工程应用价值和学术研究意义。

In this paper, the wind tunnel test of large span roof structures' dynamic wind loads have been discussed systematically, the modal decomposition method and time domain method, which was combined with the result to calculate the wind-induced vibration responses and equivalent static wind loads of (non-large-deformation) large span roof structures are also studied at the same time, and some engineering-valuable conclusions are summarized.

本文正是在这种背景下，依托武汉体育中心游泳馆屋盖的风洞试验研究，对现有的大跨屋盖结构的风荷载及风致响应计算方法做了一定的改进，在风致响应理论在实际工程中的应用上得到了一些有工程价值的结论。

Main product:The Roll-Forming M/C for bolting corrugated sheet,boltless corrugated sheet,C-section/Z-section purlin,Roof Sheet special for Latticed Frame,Floor Decking Sheet,Roll Shutter Sheet,Binding Angle Sheet,Tile-Roof Sheet,Large-Span Roof Sheet,etc.

主要产品：锁螺钉瓦板、无钉隐藏式瓦板、C型及Z型檩条、网架专用及大跨度屋面板、楼面钢承板、卷帘门板、包角板、琉璃瓦板、大跨度拱形屋面板成型设备及其各种配套设备和彩板安装专用工具等。

Summary of the geographical and climatic conditions constrained mainly in greenhouse Structural optimization design of the status quo, such as the span, chiropractors, lighting roof angle, the light roof shape, After the wall structure and roof structures for different areas in greenhouse construction provide reference information.

综述了地域和气候约束条件下日光温室主要结构优化设计的研究现状，如跨度、脊高、采光屋面角、采光屋面形状、墙体结构和后屋面结构等，为不同地区日光温室建造提供参考信息。

According to the material and disposition,the roof of common steel roof truss mill building divides into steel purlin roof and roof without purlin.

普通钢屋架结构厂房的屋盖根据屋面材料和屋面布置情况，可分为无檩屋盖和有檩屋盖。

On the anslysis of factory with steel purlin roof and factory with roof without purlin,the practicability of steel purlin roof with strengthened longitudinal horizontal brace replaces roof without purlin is evaluated.

在对有檩屋盖和无檩屋盖厂房结构分析对比的基础上，评价用纵向水平支撑加强后的有檩屋盖代替无檩屋盖的可行性。

Foods high in this vitamin include oily fish such as salmon, tuna and, and fish liver oils.

维生素D含量高的食物包括诸如大麻哈鱼、金枪鱼和鲭鱼之类的油鱼以及鱼肝油。

We need you to cosign our public letter demanding that press intimidation cease immediately, and that all charges be dropped.

我们需要您cosign我们的公共信，要求记者立即停止恐吓，并要求所有收费下降。