保护层厚度对H型钢混凝土闸墩承载能力的影响研究

发布时间：2018-06-17 03:03

本文选题：型钢混凝土 + 闸墩　；参考：《广西大学》2014年硕士论文

【摘要】：闸墩是水利水电工程泄水建筑物的重要组成部分,闸墩结构的安全直接影响着整个水利枢纽的安全。随着我国水利水电事业的发展,越来越多的大型水利水电工程开工建设,泄水建筑物的泄流量、工作水头也越来越大,闸墩受到闸门推力的作用也越来越大,单纯采用普通钢筋混凝土结构已经很难满足大推力闸墩结构的安全要求。预应力闸墩在泄水建筑物闸墩中的应用,在一定程度上解决了这个问题,但预应力闸墩存在预应力锚索在提高闸墩刚度方面作用不大、施工工艺比较复杂以及工期长等不足,仍然不能彻底解决大推力闸墩的安全问题。本论文根据型钢混凝土结构具有承载能力高、刚度大、延展性好的特点,结合工程实际提出了一种利用型钢混凝土技术在墩体和牛腿支座处配置一定H型钢的新型闸墩结构,也就是H型钢混凝土闸墩,并重点开展了保护层厚度对H型钢混凝土闸墩承载能力的影响研究。本论文利用大型通用有限元软件ANSYS来进行闸墩的承载能力分析,从闸墩的位移、应力、裂缝的分布以及承载能力等方面,论证型钢混凝土闸墩的合理性,在此基础上重点分析了保护层厚度对H型钢混凝土闸墩承载能力的影响,根据闸墩结构和型钢混凝土的特点,保护层厚度范围采用300mm-600mm,分别研究了300mm、400mm、500mm以及600mm四种不同保护层厚度闸墩的承载能力,通过研究分析得出如下结论：(1)在相同配钢量的情况下,闸墩在达到其极限承载能力之前,型钢混凝土闸墩各个部位的位移、应力、裂缝的分布和常规钢筋混凝土闸墩相近；闸墩达到极限承载能力状态时,型钢混凝土闸墩荷载比常规钢筋混凝土闸墩荷载稍大。说明型钢能代替常规钢筋混凝土闸墩墩体扇形分布的受力钢筋和牛腿支座中的纵向受力钢筋,并且型钢在闸墩内所占的空间小,有利于型钢混凝土闸墩在大推力闸墩中的应用。(2)闸墩在达到其极限承载能力之前,保护层厚度对闸墩的混凝土以及型钢各个部位的位移分布没有明显影响；闸墩达到其极限承载能力状态时,不同保护层厚度的闸墩其极限位移有所不同,随混凝土保护层厚度的增加闸墩的极限位移先增加后减小,保护层厚度为400mm的闸墩,混凝土以及型钢的极限位移位移最大。(3)H型钢在其进入屈服状态前,保护层厚度对H型钢的各个部位的应力分布无明显影响,但是对型钢屈服后的应力有一定的影响,闸墩达到其极限承载能力状态时,保护层厚度为400mm的型钢屈服长度最长,应力也最大；混凝土的应力在荷载作用的不同阶段下分布以及大小相近。(4)保护层厚度对H型钢混凝土闸墩各个部位的裂缝分布以及发展无明显影响,在荷载作用的整个过程中,闸墩的裂缝分布范围以及裂缝的发展速度相近,闸墩的裂缝主要由混凝土材料的性能决定。(5)保护层厚度对H型钢混凝土闸墩结构的极限承载能力有着较大的影响,混凝土保护层厚度从300mm增加到600mm时,承载能力先增加后减小,保护层厚度为400mm的闸墩承载能力最高。
[Abstract]:The pier is an important part of the discharge structure of water conservancy and hydropower project. The safety of the pier structure directly affects the safety of the whole water conservancy project. With the development of water conservancy and hydropower development in China, more and more large water conservancy and hydropower projects have been built, the discharge of the discharge buildings and the head of the working water are becoming larger and larger, and the gate piers are pushed by the gate. The effect of force is becoming more and more big, it is difficult to meet the safety requirements of the structure of large thrust pier simply using ordinary reinforced concrete structure. The application of the prestressed pier in the sluice pier of the discharge building has solved this problem to a certain extent, but the prestressed anchorage cable has little effect on improving the rigidity of the pier. The safety of large thrust piers can not be solved thoroughly. This paper has the characteristics of high bearing capacity, large stiffness and good ductility in this paper. A steel concrete technique of use type steel concrete technique is put forward to configure a certain type of H steel at pier body and leg support according to the engineering practice. The new type of pier structure is the H type steel concrete sluice pier, and the influence of the thickness of the protective layer on the bearing capacity of the H type steel concrete sluice pier is emphatically studied. This paper uses the large general finite element software ANSYS to analyze the bearing capacity of the pier, from the displacement of the pier, the stress, the distribution of the crack and the bearing capacity, and so on. On the basis of this, the influence of the thickness of the protective layer on the bearing capacity of the H steel concrete sluice pier is emphatically analyzed. According to the characteristics of the pier structure and the type steel concrete, the thickness range of the protective layer is 300mm-600mm, and the bearing capacity of the four different protective layers of the protective layer of 600mm and the 300mm, 400mm, 500mm and the thickness of the thickness of the protective layer are studied respectively. Through the research and analysis, the following conclusions are drawn: (1) in the case of the same amount of steel, the displacement, stress and distribution of the cracks are close to the conventional reinforced concrete pier before the pier reaches its ultimate bearing capacity. When the pier reaches the limit bearing capacity state, the load ratio of the type steel concrete sluice pier is conventional. The load of the reinforced concrete sluice pier is slightly larger. The explanatory steel can replace the conventional Reinforced Concrete Sluice Piers and the longitudinal force steel in the supporting bar and the leg support, and the space of the type steel in the pier is small, which is beneficial to the application of the steel concrete sluice pier in the large thrust pier. (2) the pier has reached its ultimate bearing capacity. Before, the thickness of the protective layer has no obvious influence on the displacement distribution of the concrete of the pier and the different parts of the steel. When the pier reaches its ultimate bearing capacity, the ultimate displacement of the pier with different thickness of the protective layer is different. With the thickness of the concrete protective layer, the limit displacement of the pier increases first and then decreases, the thickness of the protective layer is 4. The maximum displacement displacement of the pier, concrete and type steel in 00mm is the largest. (3) the thickness of the protective layer has no obvious influence on the stress distribution in each part of the H steel before it enters the yield state, but it has a certain influence on the stress after the yield of the steel type steel. When the pier reaches its limit bearing capacity state, the thickness of the protective layer is 400mm of the type steel. The length of the yield is the longest and the stress is the greatest. The stress of concrete is distributed and the size is close to the different stages of the load. (4) the thickness of the protective layer has no obvious influence on the distribution and development of the cracks in each part of the H type steel concrete sluice pier. In the whole process of the load action, the distribution of the cracks in the pier and the speed of the crack development The cracks of the pier are mainly determined by the performance of the concrete material. (5) the thickness of the protective layer has a great influence on the ultimate bearing capacity of the H type steel concrete sluice pier structure. When the thickness of the concrete protective layer is increased from 300mm to 600mm, the bearing capacity increases first and then decreases, and the bearing capacity of the pier with the thickness of the protective layer is the highest for the pier of 400mm.
【学位授予单位】：广西大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV662.2

【参考文献】