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1.
张良清 《福建林业科技》2013,40(2):179-181,205
以省道S204线将乐段孙坊至铁岭公路(孙铁公路)改扩建加宽工程为例,分析林区公路改扩建中加宽路基结合部产生沉降变形的主要原因,并提出基底加固、开挖台阶和土工织物应用以及填筑压实等处置对策。  相似文献   

2.
公路改扩建设计的技术问题探讨   总被引:1,自引:0,他引:1  
杨林  单炜  佴磊 《森林工程》2007,23(5):53-55
对旧路进行加宽改扩建是提高道路通行能力、改善车辆运行条件、降低运输成本的有效途径之一。本文结合我国旧路改扩建的现状及工程实践,对公路改扩建工程的详细调查,公路的路线平面线形、纵断面线形的设计方法,路基加宽方式的选择,新旧路面结构设计与补强,及桥梁设计中的关键技术进行了系统的分析,提出了道路设计详细调查、路线、路基路面、桥梁工程设计中的注意事项,保证公路改扩建工程的设计质量的工程措施,结论表明在旧路加宽改扩建工程中,对旧路进行系统的调查和设计中的平、纵、横线形及路基路面结构的综合设计是十分重要的,为提高旧路改扩建设计质量进行了有益的探索。  相似文献   

3.
阐述高等级公路改扩建工程的定义、方式和特点,论述国内外施工技术和理论研究现状,找出我国季冻地区高等级公路改扩建工程技术理论与实践亟待解决的问题,对新旧路基差异沉降、结合部破坏等路基稳定性问题提出今后需要开展的研究工作。  相似文献   

4.
阐述了旧路路基拓宽的加宽方式和拓宽过程中遇到的常见问题,并对一些具体问题的处理措施作了详细介绍。  相似文献   

5.
随着国家实行村村通公路以来,我国乡村公路得到了大力发展。但是随着农村经济的发展,原有的部分公路已经不能满足日益增长的交通需要,需要对原有的农村公路进行改造加宽,在对农村公路路基进行改造的过程中,做好其施工技术及质量控制是关键。  相似文献   

6.
新老路基结合部是公路拓宽与施工中的技术难题之一,本文介绍永大公路路基拓宽工程中,新老路基结合部的情况,并提出了施工对策。  相似文献   

7.
本文结合某公路维修改造工程项目高填方路堤沉降的路基加固处理方案,针对采用灌浆法加固路基进行了介绍和探讨,可为今后公路改造项目提供参考。  相似文献   

8.
采用二维有限元数值计算方法对刚性桩网复合地基加固拓宽道路下软土地基的工作性状进行系统分析。利用经现场实测数据合理性验证过的数值计算模型,分别改变桩网复合地基体系中桩体与加筋体的几何、材料力学条件,考虑不同地基处理方式和加筋布置形式,以路堤顶面新老拼接结合部的横坡改变率为差异沉降控制指标,进行设计参数敏感性量化分析。结果表明:当老路堤下地基稳定后仅对新地基加固时,不同地基加固方式对加宽路堤表面差异沉降影响很大;仅单层布置的加筋效果不明显,而采用底部多层加筋时对差异沉降的抑制效果较好,路堤顶部多层加筋可增强新老搭接处的整体强度。基于新老路堤表面横坡改变率的差异沉降控制指标进行影响因素分析,研究结论可为刚性桩网复合地基在拓宽道路工程中实现控沉功能性设计提供参考。  相似文献   

9.
本文通过对林区公路天然软土地基稳定与沉降的计算、分析,阐明了路基在填筑过程中及完工后的稳定情况,选择合理的填筑速度和稳定加固措施,从而保证路堤在施工过程中和完工后的稳定.  相似文献   

10.
为了保证市政道路旧路改造工程的耐久性,针对城市道路改造工程中会出现的旧路路况评价、旧路病害处治以及加铺结构设计方案等问题开展研究,提出了适用于市政道路的旧路路况评价方法、旧路病害处治对策以及结构补强与功能恢复的路面加铺结构设计方案,为相关的市政工程提供了良好的技术支持。  相似文献   

11.
文中根据工程实例,利用监测数据,采用规范法和拐点法详细地分析了经过处理后的软土地基在路堤填土分级加载过程中的稳定性.通过两种方法的对比分析得出一致的结论,即湿地软土地基在路堤填土分级加载过程中是稳定的,而且是与工程实际相符的.有效地控制了施工加载过程和指导施工,为今后湿地软土地基稳定性控制提供参考.  相似文献   

12.
Determining the physical and mechanical properties of soil and its behavior for engineering projects is essential for road construction operations. One of the most important principles in forest road construction, which is usually neglected, is to avoid mixing organic matter with road materials during excavation and embankment construction. The current study aimed to assess the influence of organic matter on the physical properties and mechanical behaviors of forest soil and to analyze the relation between the amount of organic matter and the behavior of forest soil as road material. A typical soil sample from the study area was collected beside a newly constructed roadbed. The soil was mixed with different percentages of organic matter(control treatment, 5, 10, and 15% by mass) and different tests including Atterberg limits, standard compaction, and California bearing ratio(CBR) tests were conducted on these different soil mixtures. The results showed that soil plasticity increased linearly with increasing organic matter.Increasing the organic matter from 0%(control) to 15%resulted in an increase of 11.64% of the plastic limit and 15.22% of the liquid limit after drying at 110 ℃. Also,increasing the organic matter content reduced the soil maximum dry density and increased the optimum moisture content. Increasing the organic matter from 0 to 15% resulted in an increase of 11.0% of the optimum moisture content and a decrease of 0.29 g/cm~3 of the maximum dry density. Organic matter decreased the CBR, which is used as the index of road strength. Adding 15% organic matter to the soil resulted in a decrease of the CBR from 15.72 to 4.75%. There was a significant difference between the two drying temperatures(60 and 110 ℃) for the same organic matter mixtures with lower water content values after drying at 60 ℃. The results revealed the adverse influence of organic matter on soil engineering properties and showed the importance of organic matter removal before excavation and fill construction.  相似文献   

13.
Cost estimation is probably the most decisive factor in the process of computer-aided, preliminary planning for low-volume road networks. However, the cost of construction is normally assumed to be route-independent for a specific project area, resulting in sub-optimal layouts. This is especially true for mountainous terrain and in areas with unstable subsoil. Here, we present a model for more accurately estimating spatial variability in road life-cycle costs, based on terrain surface properties as well as geological properties of the subsoil. This parametric model incorporates four structural components: embankment, retaining structures, pavement, and drainage and stream-crossing structures. It is linked to a geo-database that allows users to derive location-specific parameter values as input. In applying this model, we have demonstrated that variability in costs ranges widely for mountainous areas, with the most expensive construction being approximately five times greater there than on more favorable sites. This variability strongly affects the optimal layout of a road network. First, when location-specific slope gradients are considered, costs are reduced by about 17% from those calculated via currently available engineering practices; when both slope gradient and geotechnical formations are included, those costs are decreased by about 20%. Second, the length of the road network is increased by about 4% and 10% respectively, compared with current practices.  相似文献   

14.
孔令玉  龚莉 《森林工程》2007,23(3):34-36
对季冻区旧路改扩建工程路基拓宽中,容易出现破坏现象的成因进行了分析,重点结合了季冻区的已建或在建的改扩建工程的施工经验,对季冻区的路基拓宽的特殊性进行了技术分析。  相似文献   

15.
Forest roads require important design specifications to ensure all-season access for various vehicles. Long and heavy log trucks can face serious maneuvering problems on forest roads due to insufficient amount of area to the left for road widening on horizontal curves. In order to provide safe and continuous shipment and transportation,appropriate curve widening areas should be provided for long vehicles along horizontal curves. In this study, a statistical model was developed to provide curve-widening solutions for long trucks(e.g., those with 18 wheels) considering various curve radius and deflection angles. The dynamic curve widening feature of Plateia 2013 program was employed to calculate curve widening for the specified vehicle. During the solution process, nine different horizontal curve diameters from 10 to 50 m(by 5 m intervals)and 17 different deflection angles from 90° to 170°(by 5°intervals) were evaluated to run horizontal curve-widening analysis. Using a multiple regression model, we made suitable predictions about curve widening. The curvewidening areas decrease as the horizontal curve radius increases, while increasing the deflection angle on horizontal curves increases curve widening areas. Clearly, the computer-based dynamic curve widening model developed in this study can be effectively used in determining optimum widening for horizontal curves by evaluating the number of alternatives that fit geometrical specifications and vehicle types.  相似文献   

16.
根据林区道路修建的有关信息 ,建立了基于GIS技术的林区道路路线方案设计流程 ,在此基础上 ,应用层次分析法 ,建立林区道路路线方案优化的层次结构模型 ,对影响林区道路选线的多因素进行了综合分析 ,提出了基于GIS技术林区道路选线方案优化流程。该方法将对林区道路的修建提供一定参考价值  相似文献   

17.
本文主要介绍了填石路堤施工的材料、机械要求和有关的技术要求。通过在厚大公路上的应用 ,证明填石路堤在山区公路中是一种经济合理的形式  相似文献   

18.
易文  胡伟勋 《森林工程》2005,21(2):47-48
填方是路基的一种基本形式,其质量关系到整条道路的质量,不同路段填方应采取不同的处理措施,以保证其强度。  相似文献   

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