南方山区高填方圆管涵受力特性离心模型试验研究

发布时间：2018-03-09 10:47

本文选题：南方山区　切入点：高填方　出处：《长安大学》2015年硕士论文　论文类型：学位论文

【摘要】：涵洞结构是公路工程中必不可少的构造物之一,公路工程中涵洞结构物平均3~4座/公里。在山区高速公路的修建中,高填方圆管涵工程的数量更多,但高填方圆管涵的设计计算方法与施工技术至今仍不完善,导致设计计算结果与圆管涵实际受力相差很大,工程中圆管涵病害不断发生。只有对圆管涵、填土、地基与基础共同作用机理认识清楚,准确设计计算圆管涵结构所受荷载,才可使计算结果与实际情况相符,确保高填方圆管涵的合理受力与正常使用以及设计的可行性、经济性、实用性。在对包茂高速沿线自然地理特征及工程地质资料进行收集、整理、分析的基础上,针对南方山区软土分布广泛、沟谷地形复杂、圆管涵填土高度较大等特点,在综合考虑填土高度、地基土模量、沟谷地形、减荷措施等因素的基础上,采用离心模型试验方法,研究不同工况下高填方圆管涵的受力特性,得出的主要研究成果有:(1)平地中出现等沉面的最低填土高度为6.0m,等沉面范围一般在5.6m~8.2m,据此认为圆管涵顶填土高度大于6.0m即可界定为高填方涵洞;(2)平地中涵顶填土高度在15m~50m,涵周土压力及涵洞结构应力较大。建议填土高度15m~20m、20m~40m、40m~50m分别在涵顶铺设50cm~75cm、75cm~100cm、100cm~125cm的EPS板;(3)平地中涵顶填土高度20m,地基土模量大于15MPa,涵洞易发生破坏,建议在涵顶铺设50cm~75cm的EPS板,以减小涵顶土压力;(4)沟谷宽度大于5倍的涵洞跨径,沟谷坡度大于45°,涵顶填土高度超过20m,建议在涵顶铺设50cm~100cm的EPS板,以减小涵顶土压力;(5)通过离心模型试验研究,得出多因素影响条件下高填方圆管涵垂直土压力及土压力集中系数的回归公式;(6)基于研究成果,提出了南方山区高填方圆管涵设计计算方法与施工技术建议。论文成果为南方山区高填方圆管涵设计与施工提供了科学依据,具有重要的理论意义与工程应用价值。
[Abstract]:Culvert structure is one of the essential structures in highway engineering. The average culvert structure in highway engineering is 3 ~ 4 / km. In the construction of highway in mountainous area, the number of high-filled circular pipe culvert engineering is even more. However, the design and calculation method and construction technology of high fill circular pipe culvert are still not perfect, which leads to a great difference between the design and calculation results and the actual force of circular pipe culvert, and the disease of circular pipe culvert occurs constantly in engineering. Only for circular pipe culvert, fill soil, The mechanism of interaction between foundation and foundation is well understood. Only when the load of circular pipe culvert structure is designed and calculated accurately, can the calculation result accord with the actual situation, and ensure the reasonable force and normal use of high fill circular pipe culvert, as well as the feasibility of design. Economy and practicability. On the basis of collecting, arranging and analyzing the natural geographical characteristics and engineering geological data along Baomao Expressway, aiming at the characteristics of the wide distribution of soft soil in the southern mountainous area, the complicated topography of the gully and the high fill height of the circular pipe culvert, etc. Based on the comprehensive consideration of such factors as the height of the fill, the modulus of the foundation soil, the topography of the gully and the measures of load reduction, the mechanical characteristics of the high filled circular pipe culvert under different working conditions are studied by the centrifugal model test method. The main research results obtained are as follows: 1) the minimum fill height of equal-settlement surface in flat land is 6.0 m, and the average equal settlement surface range is 5.6 m ~ 8.2 m. It is considered that the top fill height of circular culvert culvert is more than 6.0 m, which can be defined as the top fill of high fill culvert / culvert. The soil pressure around the culvert and the stress of culvert structure are larger than 15m ~ 50m. It is suggested that the fill height of the culvert is 15m ~ 20m ~ 20m ~ 20m ~ 40m ~ 40m ~ 50m, respectively, and the culvert is liable to be destroyed by laying 50cm ~ 75cm ~ 75cm ~ (75) cm ~ (-1) ~ 100cm ~ (-1) cm ~ (-1) EPS plate with 125cm ~ (12) cm ~ (-1)) height of the culvert in flat ground, and the modulus of the foundation soil is more than 15MPa, and the culvert is liable to damage. It is suggested to lay 50 cm / 75 cm EPS plate on the top of the culvert to reduce the soil pressure of the culvert top and to reduce the span of culvert with a width of more than 5 times. The slope of the culvert is more than 45 掳, the height of the culvert top fill is more than 20 m, and the EPS plate of 50 cm / 100 cm is recommended to be laid on the top of the culvert. In order to reduce the soil pressure of culvert top, the regression formula of vertical earth pressure and the concentration coefficient of earth pressure of high filled circular pipe culvert under the condition of multi-factor influence is obtained by centrifugal model test. This paper puts forward the design calculation method and construction technology suggestion of high filled circular pipe culvert in southern mountainous area. The results of this paper provide scientific basis for the design and construction of high filled circular pipe culvert in southern mountainous area, and have important theoretical significance and engineering application value.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U449.83

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