现浇连续箱粱支架的预压控制方法

介绍了高速公路现浇连续箱梁施工工艺及施工难点，提出了一种高速公路现浇连续箱梁模板支架实用预压控制方法，并结合实例对该方法进行了验证。     

现浇连续箱粱支架的预压控制方法

介绍了高速公路现浇连续箱梁施工工艺及施工难点,提出了一种高速公路现浇连续箱梁模板支架实用预压控制方法,并结合实例对该方法进行了验证.     

等高度预应力混凝土连续箱梁支架预压分析

以湖南某地项目二标段一座等高度预应力连续箱梁桥为例,介绍了连续箱梁支架预压的要求、预压荷载、加载范围及加载操作过程,提出了在加载过程操作中应注意的问题,为连续箱梁支架预压施工提供参考。     

支架法现浇连续箱梁的支架施工控制

文章简述了支架法现浇连续箱梁的施工控制和方法,结合观庄互通式立交A匝道桥工程,分析了现浇连续箱梁的支架工程施工的控制特点,总结出该桥在支架工程施工中应注意的问题及控制经验。     

钢管桩支架在和龙高架桥现浇箱梁中的应用

和龙高架桥现浇箱梁经过方案比较选用钢管桩支架施工.钢管桩基础以零沉降控制,免预压,施工中整体监控.支架通过吊蓝设备由下至上进行拆卸.钢管桩支架在表土为软质地基中使用充分发挥了优势,支架体现了较高可靠性,取得理想效果.     

连续箱梁的钢支架施工方法

该文介绍了现浇钢筋混凝土连续箱梁的钢支架施工方法,特别提出单点法支架预压,有效地效少了工作量和缩短了工期;文中对连续箱梁混凝土现浇的方法作了探讨,有效地防止了钢筋混凝土连续箱梁裂缝过大质量通病。     

大、变截面普通钢筋砼箱梁施工要点分析

通过简要分析(16 18 16)m现浇变截面箱梁的施工，对此种结构的施工、监理重点环节予以提出，并在施工中加以重视。     

现浇混凝土箱梁支架预压技术

工程概况 某桥主箱梁为等高2.8m斜腹板预应力钢筋混凝土箱梁,单箱双室大挑臂整体断面形式。主桥宽32.5m。主桥断面如图1所示。主梁支架体系采用F630钢管桩,排距6m,列距5＋4＋3＋3＋3＋4＋5m布置;承重横梁采用I40b工字钢双拼;纵梁采用14道贝雷架;分配梁采用I20工字钢间距500mm。     

软基上搭满堂支架现浇连续箱梁的施工

现浇箱梁因其整体性好，外形美观，可做成复杂形状，广泛地应用于高速公路跨线桥和城市道路高架桥。介绍了广珠东线某立交的一段现浇连续箱梁桥的施工，探讨了如何保质保量地在软基上搭满堂支架来现浇连续箱梁。     

钢管桩支架在和龙高架桥现浇箱梁中的应用

和龙高架桥现浇箱梁经过方案比较选用钢管桩支架施工。钢管桩基础以零沉降控制,免预压,施工中整体监控。支架通过吊篮设备由下至上进行拆卸。钢管桩支架在表土为软质地基中使用充分发挥了优势,支架体现了较高可靠性,取得理想效果。     

浅谈支座设计

浅析支座的工作原理、几种类型和布置方式。     

回归趋势添加法及其在隧道监控量测数据处理中的应用

基于回归分析理论和指数平滑加权理论,提出回归趋势添加法．以隧道地表下沉实测数据为例,采用回归趋势添加法,对监控量测数据进行处理．分析结果表明：回归趋势添加法除可确定隧道现场监控量测频率外,还能预测数据发生突变的时间,解决现有数据处理手段不能有效地对隧道监测数据产生突变的情形进行及时预警的问题．该方法较其他方法操作更加简单,反馈信息更为准确,对隧道现场监控量测数据进行预测、预警具有明显的优越性．     

整体式贝雷梁支架在现浇系杆拱桥上的应用

研究了采用贝雷梁作为支架进行系杆拱桥现浇施工的方法;对共用钢管桩支撑的整体式贝雷梁支架进行理论模拟,并结合现场加载试验研究了施工支架的分析计算方法及变形;通过对施工后支架的实际变形和理论变形的比较进一步验证了理论模型的正确性。研究表明,利用这种整体式支架进行系杆拱桥的施工是可行的。     

浅析爆破方法在隧道施工中的应用

灌溉输水洞是一个长为735.542 m的隧道,受区域构造影响施工工区形成了以断层为主的围岩地质条件。结合此工程的实际情况,详细分析了隧道开挖方法及控制爆破技术,并给出了岩爆地段的特殊施工技术,为类似工程的施工提供了一定的借鉴作用。     

谈沥青评价方法的应用

通过试验中的实例 ,对温度敏感性的各项技术指标进行了简要介绍 ,剖析了各项指标所代表的具体涵义 ,指出了引用这些指标的实际意义     

A new algorithm for non-newtonian flow and its application in mould filling process

The simulation of injection molding process requires a stable algorithm to model the molten polymer with non-isothermal non-Newtonian property. In this paper, a staggered and iterative scheme is particularly designed to solve the velocity-pressure-temperature variables. In consideration of the polymer characteristic of high viscosity and low thermal conductivity, the non-Newtonian momentum-mass conservation equations are solved by the Crank-Nicolson method based split (CNBS) scheme, and the energy conservation equation with convective character is discretized by the characteristic Galerkin (CG) method. In addition, an arbitrary Lagrangian Eulerian (ALE) free surface tracking and mesh generation method is introduced to catch the front of the fluid flow. The efficiency of the proposed scheme is demonstrated by numerical experiments including a lid-driven cavity flow problem and an injection molding problem.     

GTM法在路面施工中的应用

结合GTM法技术在张石高速公路中的实践应用,介绍GTM法的设计原理、施工工艺和质量控制体系,尤其是对施工过程质量控制点和沥青路面最大密实度标准研究分析,有效地降低了工程施工费用;提高了路面的服务寿命。     

搁浅船舶扳正过程计算方法

为了研究搁浅船舶的打捞, 计算了船舶扳正过程中搁坐力和纵倾角的变化, 分析了船舶舱室内的自由液面在搁浅船舶扳正过程中的作用。根据搁浅船舶的受力特点, 建立了其力学模型。针对传统搁坐力计算方式的缺点, 利用GHS软件模拟搁浅船舶的扳正过程, 并以某搁浅船舶为例, 求解该过程中各搁坐点的搁坐力、总搁坐力、横倾角和纵倾角。通过仿真模拟, 比较了船舶不同搁浅状态的扳正过程, 分析了搁坐点位置、吃水、船体型线和船舶重力分布对搁浅船舶受力和姿态的影响。分析结果表明: 搁坐点位置相对分散或船体吃水较深时, 船体的纵倾角变化相对较小, 变化量为其他类型的0.1%~2.0%;搁坐点关于船舯非对称产生的总搁坐力变化量相对搁坐点关于船舯对称产生的总搁坐力较小, 前者变化量为后者的35%~65%;舱室内自由液面的存在加大了搁浅船舶打捞的难度, 因此, 在制定打捞方案时应该着重考虑其影响; 施工过程中也应控制搁浅船舶翻转的速度, 避免阻碍扳正工作或对船舶产生进一步的破坏。     

A comprehensive evaluation method for kinematic accuracy of space manipulator based on analytic hierarchy process

The kinematic accuracy of space manipulator determines whether the spacecraft performs normally or not. Problems pertaining to structural deformation have received increased attention in recent times. In the space manipulator systems, flexible arms and joints can induce drastic dynamic instabilities. In applications such as the space station, kinematic error due to structural deformation can jointly affect the performance characteristics. And it is crucial for accuracy control of space manipulator to establish a precision index. Here we analyze the dynamics characteristic of flexible space manipulator considering the hysteresis of harmonic reducer based on method of nonconstraint boundary modal. For the sake of describing the output accuracy, we integrate the method of analytic hierarchy process(AHP) to establish a comprehensive evaluation index. A numerical simulation is performed to analyze the nonlinear dynamic characteristics of space manipulator with harmonic reducer. With the analysis of accuracy assessment, the relation among the hysteresis angle, rigidity and output accuracy is revealed. Considering the elastic modulus of flexible space manipulator and the hysteresis angle of harmonic reducer, we conduct an evaluation of output characteristics of flexible space manipulator with the proposed comprehensive evaluation index. The accuracy evaluation of output characteristics based on the proposed comprehensive evaluation index is implemented in the initial stage of space manipulator’s design, which can not only solve the problems existing in the design but also save cost savings for ground tests. The results can be used in designing and optimizing future space manipulators, which may provide valuable references for design and thermal control of the space manipulator.     

Topology optimization design and strength analysis of the hoist bracket for rescue helicopters

The hoist bracket links the rescue hoist with the helicopter cabin, and its structure design greatly affects the operation convenience and safety of the hoistman and lifeguard in the rescue process with a helicopter.This paper firstly builds the force model of the hoist and bracket, and gives five kinds of typical working conditions as the design ones of the bracket. Then this paper puts forward a design process of the hoist bracket based on the topology optimization and strength analysis with the 3D modeling and finite element analysis. This design process can make the bracket’s structure lightweight by achieving the optimal material layout under the conditions of maximizing the static stiffness or minimizing the compliance of the bracket. And this improves the dynamic performance of the helicopter, and reduces the fuel consumption and cost under the strength constraints. Finally,taking the design of the hoist bracket used in a rescue helicopter as an example, this paper illustrates the proposed model and method. The analysis results show that the mass of the hoist bracket decreases by 12.5% while the static stiffness of the hoist bracket is achieved. The optimization design results meet the strength requirements of the hoist.