萍州大桥8#墩钢板桩围堰施工方案计算及土弹簧简化计算方法研究

发布时间：2018-04-10 18:50

本文选题：围堰 + 钢板桩　；参考：《湘潭大学》2015年硕士论文

【摘要】：钢板桩围堰是最常见的防水围堰形式,尤其在水下承台、水下墩(台)身施工中,它不仅可以作为封底混凝土的模板,而且能和混凝土共同作用起到防水作用,在围堰施工中还可以作为挡水结构。在钢板桩围堰施工方案计算中,传统的计算方法采用的简化计算模型,土层间距一般取经验值,少有文献报道研究。本文以萍洲大桥8#墩围堰为工程背景,采用Midas/Civil和Abaqus CAE等软件,对围堰施工方案进行设计和受力计算,计算内容主要包括钢板桩“踢脚”失稳计算、钢板桩围堰抗管涌计算、封底混凝土厚度计算、钢板桩结构计算、内支撑结构计算、强度刚度验算和压杆失稳计算等。本文中所使用的方案计算方法方便快捷,是现今施工中常用的计算方法。本方案设计中土层间距经验取值为1m,本文通过改变土弹簧计算中的土层间距,得到不同的弹簧系数K值,作用到计算模型中而得到了多种不同计算结果,与有限元分析软件所建模型进行对比,并得出结论。主要的研究内容如下:(1)在实际工程中,一般采用简化计算的方法进行施工方案设计。这种计算方法方便快捷,因此被广泛使用。本文采用此类计算方法对萍洲大桥8#墩围堰进行设计和受力计算,把土体简化成一个具有弹性系数的弹性支撑。(2)在模型简化过程中,土层间距的取值采用的经验值,本文通过对此值进行改变,采用六个对照组并与有限元模型进行对比,发现简化计算在一定程度可以反映结构的实际受力情况,但取值过大或过小会对结果造成不良的影响。(3)通过对照组中得出在进行简化计算的过程中,对土弹簧K值进行取值时,土层间距不可过大,也不宜过小,取0.5、1.0、1.5都比较接近模拟值。从本文中可以看出应力值随间距增大而增大同,弯矩值随间距增大而增大,位移随间距增大而增大,剪力随间距增大而增大。
[Abstract]:Steel sheet pile cofferdam is the most common waterproof cofferdam, especially in the underwater pile cap, underwater pier (platform) construction, it can not only be used as the bottom concrete template, but also can work with concrete to play a waterproof role.In the construction of cofferdam, it can also be used as a water retaining structure.In the calculation of the construction scheme of steel plate pile cofferdam, the simplified calculation model is adopted in the traditional calculation method, and the interval between the soil layers is generally taken as the empirical value, which is seldom reported in the literature.In this paper, based on the engineering background of the cofferdam of Pinzhou Bridge, using Midas/Civil and Abaqus CAE software, the design and stress calculation of cofferdam construction scheme are carried out. The calculation contents mainly include the calculation of "kick foot" instability of steel sheet pile and the calculation of pipe bore resistance of steel plate pile cofferdam.The bottom concrete thickness calculation, plate pile structure calculation, internal support structure calculation, strength and stiffness check calculation and compression rod instability calculation and so on.The calculation method used in this paper is convenient and quick, and it is commonly used in construction nowadays.The empirical value of soil spacing is 1 m in the design of this scheme. By changing the interval between soil layers in the calculation of soil springs, different spring coefficients K are obtained, and many different calculation results are obtained by acting on the calculation model.The model is compared with the finite element analysis software, and the conclusion is drawn.The main research contents are as follows: (1) in practical engineering, the simplified calculation method is generally used to design the construction scheme.This calculation method is convenient and fast, so it is widely used.This paper uses this kind of calculation method to carry on the design and the force calculation to the piers cofferdam of Pinzhou Bridge, and simplifies the soil mass into an elastic bracing with elastic coefficient.By changing this value, using six control groups and comparing with the finite element model, it is found that the simplified calculation can reflect the actual stress of the structure to a certain extent.However, too large or too small value will have a bad effect on the result.) in the control group, it is concluded that in the process of simplified calculation, the interval between soil layers should not be too large or too small when the K value of soil spring is taken.The values of 0.5 ~ 1.0 ~ (-1) U ~ (1.5) are close to the simulated values.It can be seen from this paper that the stress value increases with the increase of spacing, the moment value increases with the increase of spacing, the displacement increases with the increase of spacing, and the shear force increases with the increase of spacing.
【学位授予单位】：湘潭大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U445.556

【共引文献】