摘要
随着我国经济迅猛发展,中国融入全球经济的步伐也越来越快。中国工业化步伐正在以世界罕见的速度迈进,因此需要修建大量的土木工程,为了保证各项工程的实施,大量的支挡结构得到了广泛的应用。挡土墙是防止土体坍塌的挡土结构,是支挡结构重要形式之一。重力式挡土墙由于其就地取材、施工简单、刚度大、成本低的优点,应用最为广泛。
虽然重力式挡土墙应用非常广泛,但其计算过程非常复杂。目前,大多仍采用手算、查表或直接套用挡土墙标准图集等方法来进行挡土墙设计计算,工作量很大,且无法灵活选择挡土墙的类型及断面,因此,开发一套适用的重力式挡土墙计算软件,是非常必要的。
在众多编程语言中,Visual Basic 2008完全采用面向对象的编程技术,为开发Windows应用程序、Web应用程序提供了最迅速、最简捷的方法。它不仅功能强大而且简单易学,并且可以完全兼容Windows7/XP/Vista等操作系统,很适合软件开发,被人们广泛应用。
本文首先探讨了库仑主动土压力系数、朗肯主动土压力系数以及《建筑地基基础设计规范》(GB 50007-2002)附录L中采用的主动土压力系数的差别与联系,并利用MATLAB对主动土压力系数Ka常用表达式中的影响参数进行分析,得出各参数影响程度的大小;然后利用MATLAB比较了按照《建筑地基基础设计规范》(GB 50007-2002)附录L中采用的主动土压力系数计算时的主动土压力和该规范中主动土压力系数不考虑均布荷载影响、把均布荷载折算为土层厚度计算时的主动土压力这两者之间的差值大小;利用MATLAB比较了在朗肯条件下用黏性填土主动土压力常用计算公式计算的主动土压力和用《建筑地基基础设计规范》(GB 50007-2002)附录L中采用的主动土压力系数计算的黏性填土主动土压力这两者之间的差值大小;最后根据地基基础、挡土墙的相关规范、规程、图集以及一些参考文献,分析了重力式挡土墙设计的计算过程,将挡土墙的计算过程公式化,然后用Visual Basic 2008编程,开发出一套比较完善的重力式挡土墙计算软件。该软件涵盖了多种形式挡土墙的多种工况,设计过程清晰易懂,通用性较强,便于广大设计人员使用。该软件可以通过计算机代替设计人员进行大量的计算和验算,设计人员只需根据计算机的计算结果进行断面修改和尺寸调整,这样可以显著地提高工作效率。
With China's rapid economic development, the pace of China's integration into the global economy is faster and faster. The pace of industrialization in China is rare speed into the world, so we require the construction of a large number of civil engineering. In order to ensure the implementation of various projects, a large number of retaining structure have been widely used. As an important form of retaining structure, retaining wall is to prevent the collapse of soil. Due to the advantages of its use of local materials, simple construction, high rigidity and low cost, gravity retaining wall is the most widely used.
Although gravity retaining wall is widely used, but its calculation is very complicated. Look-up table, hand-counting and standard atlas are still the most popular methods for retaining wall design.These methods need heavy workload, and can’t flexibly select retaining wall’s type or cross-section. So it is very necessary for us to develop a calculation software of gravity retaining wall.
In many programing languages, Visual Basic 2008 fully adopt object-oriented programming techniques, providing a fastest and most simple way for Windows application program and Web applications program. It is not only powerful but also easy to learn, and can be fully compatible with Windows 7/XP/Vista and other operating systems. As it is suitable for development of software, it has been widely applied by people.
Firstly, Differences of Coulomb active earth pressure coefficient, Rankine active earth pressure coefficient, and the active earth pressure coefficient in "Building Foundation Design Code" (GB 50007-2002) Appendix L are discussed. The parameters in the commonly used expression of active earth pressure coefficient Ka are analyzed with MATLAB, and the degree of influence of each parameter is done. Secondly, according to active earth pressure coefficient in "Building Foundation Design Code" (GB 50007-2002) Appendix L ,and in the use of it ,then we get the results of active earth pressure. The active earth pressure coefficient does not consider the influence of uniform load, the uniform load is converted into the soil thickness, then we get the results of active earth pressure. We compare the difference between the results of the two active earth pressure with MATLAB. Under the Rankine, we get the results of active earth pressure of cohesive backfill with the commonly used calculation formulas. Under the Rankine, we get the result of active earth pressure of cohesive backfill with active earth pressure coefficient in"Building Foundation Design Code"(GB 50007-2002) Appendix L. We compare the difference between the results of the two active earth pressure with MATLAB. Finally, according to the relevant codes and atlas of foundation and retaining wall and some references, a analysis of the gravity retaining wall design calculation process is made. The calculation process is formulated, In turn,these are programmed with Visual Basic 2008, then we get a gravity retaining wall calculation software. The software includes many conditions of a variety forms of retaining wall, and the design process is clear and understandable, and usefulness is universal. So,it is easy to use for the general designers. The software can be designed by computer instead of a large number of personnel in the calculation of checking. The designers simply make the amendments of section and the adjustments of size according to the results of the computer, and this can significantly improve the work efficiency.
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