共查询到20条相似文献,搜索用时 62 毫秒
1.
灰色模型在路堤沉降预测中的应用 总被引:1,自引:0,他引:1
本文以Lagrange插值法和等维新息模型为基础,建立了路堤沉降预测的非等时距等维新息模型.通过实例分析,证明了该方法的可行性. 相似文献
2.
3.
灰色Verhulst模型预测软土地基建筑物的沉降 总被引:19,自引:0,他引:19
根据软土地基建筑物的沉降特性;用Verhulst模型方法建立建筑物沉降量预测模型,能运用较少的沉降观测数据建立起可靠性很好的预测模型 ,具有理论和实践意义。 相似文献
4.
高速公路粉喷桩复合地基的沉降预测不仅可以反映路基的沉降发展趋势,而且可以通过预测的沉降量来反映出路基的加固效果及稳定性,为后续工序的开展提供指导。以某高速公路粉喷桩复合地基预压期的监测结果为例,运用改进的灰色模型建立非等时距的GM(1,1)预测模型,并用后验差法对其预测精度进行检验。结果表明,改进的灰色模型的预测精度较高,能作为粉喷桩复合地基沉降预测的一种方法。 相似文献
5.
6.
根据软土地基建筑物的沉降特性;用Verhulst模型方法建立建筑物沉降量预测模型,能运用较少的沉降观测数据建立起可靠性很好的预测模型,具有理论和实践意义. 相似文献
7.
非等时距加权灰色预测模型及其在形变预报中的应用 总被引:1,自引:0,他引:1
本文根据变形观测数据有时出现非连续性的特点以及各期观测数据对建模的作用不同,提出了非等时距加权灰色预测模型,用以弥补等时距灰色预测模型处理此类数据的困难,实例分析表明,模型预测值和实测值吻合相当好。 相似文献
8.
由于深基坑工程数量激增,施工造成的坍塌等事故屡屡发生,所以深基坑施工中的变形预测非常重要。采用灰色理论建立适当的模型,并将该模型应用到实际工程中,得出以下的结论:(1)灰色GM(1,1)模型、等步距及非等步距GM(1,1)模型的建模条件;(2)将灰色理论应用到工程实例中,所取得的结果较为理想,可以进一步在类似工程中推广使用;(3)由于等步距灰色模型与非等距模型相比误差小很多,因而较易推广于实际工程中,同时,在实测值和预测变形精度上,非等步距灰色模型均较滞后,应当谨慎应用。 相似文献
9.
灰色系统理论成功地解决了许多信息不完全的预测问题,并得到了广泛的应用。灰色模型的建立,是以等时距原始数据作为前提条件的。由于在实际应用时所获取的数据往往不是等时距的,难以建立其预测模型。为了克服灰色模型以上缺点,对灰色模型进行了改进,建立了不等时矩的灰色预测模型,并应用于某电厂烟囱基础沉降预测中。结果表明:改进灰色预测模型精度好。 相似文献
10.
灰色理论在路基沉降预测中的应用及其改进 总被引:1,自引:0,他引:1
系统介绍了灰色理论预测模型在路基沉降预测中的应用,并对灰色模型进行了改进,建立了五个灰色理论预测模型,通过模型预测值与实测值比较,得出灰色理论预测模型适合于沉降过程曲线发展缓慢的软土路基沉降预测,而采用灰数等维递补动态预测模型和改进的灰色模型具有更高的预测精度。 相似文献
11.
12.
Fernando Moreu Billie F. Spencer Jr. Doug A. Foutch Sandro Scola 《Structure and Infrastructure Engineering》2017,13(2):273-286
To increase profitability, add capacity and comply with new federal regulations on bridge safety, North American railroads are exploring means to improve the management of their bridge networks. Current maintenance, repair and replacement (MRR) decisions are informed by bridge inspections and ratings, which recommend observing the response of bridges under trains. However, an objective relationship between bridge responses and the associated impact to railroad operations has yet to be established. If the consequences of MRR decisions could be better determined, then the railroads could more effectively allocate their limited resources. Chief bridge engineers from different Class I railroads provided the values of displacements and assessment used to develop this paper. Researchers monitored displacements from over 50 train crossing events and related them to decisions on operations and maintenance. This paper develops an approach for consequence-based management of bridge networks for making network MRR decisions, employing fragility curves to relate service condition limit states to transverse displacement. The operational costs associated with these service conditions can estimate the total costs of a given MRR policy. In this way, optimum MRR decisions can minimise the total network costs. This framework provides a consistent approach for the prioritisation of railroad bridge MRR decisions. 相似文献
13.
Xin LIANG Qian-gong CHENG Jiu-jiang WU Jian-ming CHEN 《Frontiers of Structural and Civil Engineering》2016,10(4):488-498
The research on the mechanism of pile-soil-cap-goaf interaction and settlement of high-speed railway bridge located in mined-out area is still relatively rare. By taking the pile group of Guanshandi bridge foundation in Hefei- Fuzhou high-speed railway as the prototype, a model test is carried out. According to the similarity theory, the similar constant is derived and the similar model material is determined. Meanwhile, three types of data including the bearing behavior of piles, and the settlement law, and soil among piles are investigated. It can be found that: the influence of goaf on the bearing capacity of pile is inversely to the loading degree, the larger of loading degree, the smaller impact of goaf on the bearing capacity. There is no negative side friction can been found in pile body and the degree of downward tendency for the barycenter of side friction layout is obvious for piles in goaf. Although the bearing ratio of soil resistance under cap is relatively large, the cap effect is suggested be ignored considering the characteristic of goaf. There is a maximum critical value for the uneven settlement of pile group in goaf, and when the value is reached, the uneven settlement stop growing anymore. In addition, the formula for calculating bearing capacity and settlement of pile group in goaf based on test results, theory analysis and related standard is established. 相似文献
14.
15.
16.
17.
在对成都粘土流变本构模型进行研究的基础上,应用Burgers体模型对成—绵—乐高速铁路成都牛龙路一带地基土建立目标函数。运用分层迭代反演土层的粘-弹性参数,以实测地基沉降为基础,对观测后期沉降进行预测,并与后续观测记录对比,从而验证了Burgers模型可在一定精度下满足沉降预测的要求,为本工程安全运营提供指导,并为同类研究提供了依据。 相似文献
18.
19.
以高铁桥墩边地铁基坑围护设计为研究对象,借助有限元程序分析基坑开挖过程中对高铁桥墩桩基础的变形影响,对后期施工监测提出了理论指导意见,以期保证施工安全,杜绝安全事故隐患。 相似文献
20.
对桩基础的承载能力进行了分析,深入地讨论了桩的负摩阻问题和群桩应力现象,对如何有效地进行桩基础设计提出自己的看法,解决了桥梁桩基础设计的相关问题。 相似文献