摘 要
此次设计的二级公路全长2576.542m，设计车速60km/h，双向两车道，无中央分隔带。
该设计首先根据远景设计交通量确定公路等级及相关技术规范和标准，并通过对当地地形、气候、水文、地质等资料的收集，并且在此基础上进行路线方案论证与比选，选择出合理的设计方案，确定了线路的平面布置；结合当地的具体情况以及本地区的未来发展计划，合理确定平曲线、竖曲线的半径及缓和曲线长度的选用；按照行车安全舒适、线形美观流畅的原则对平、纵线形进行了合理的组合。横断面设计严格按照技术标准及根据当地实际情况绘制，确定了路基宽度、高度及边坡坡度及路拱和超高，并且对路面结构层材料、排水等进行了设计。
本设计说明书较为系统地讲述了该二级公路的设计方案、水文地质条件、原理及步骤，共设十章。主要内容包括：路线方案的拟订和选择、平面设计、纵断面设计、横断面设计、路基设计、路面设计、排水设计、概算、专题等。
关键词：二级公路；平面设计；纵断面设计；横断面设计；路基设计
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Abstract
The design of the Secondary Road is 2576.542m.The design speed is 60km/h and did not set up the central of separation strip.
According to the design of highway traffic vision and determine the level technical specifications and standards, and based on the local terrain, climate, hydrology, geology, as well as data collection. Then, based on route project argumentation and selection to select the reasonable design scheme and determine the line layout; combined with local specific situation and the region's future development plan, then reasonable vertical plane curve, the curve radius and the length of the curve; according to the traffic safety and comfortable, the principle of linear beautiful fluent, the reasonable vertical alignment. Cross-sectional design is according to the technical standards and strict according to local actual condition, so we can determine the roadbed width, height and slope and road arch and high. And the pavement structure layer materials, drainage, etc.
The design manual systematically tells the design of the Secondary Road scheme, hydrogeological conditions, principles and steps of ten chapters. Main contents include: route and choose the scheme design, graphic design, longitudinal and transverse design, roadbed design, design, drainage design, project budget, etc.
Keywords:：Secondary Road；Planar Design；Longitudinal Design；Cross-sectional Design；Roadbed Design
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目 录
第一章 绪 论 .......................................................................................................................... 1 1.1 选题意义 ......................................................................................................................... 1 1.2 中国公路发展概况 ......................................................................................................... 1 1.3 工程概况 ......................................................................................................................... 1 1.4 本文研究内容 ................................................................................................................. 1 第二章 路线方案的拟定和选择 .............................................................................................. 3 2.1 交通量的预测 ................................................................................................................. 3 2.2 方案的确定和选择 ......................................................................................................... 3
2.2.1 选线原则 ...................................................................................................................... 3 2.2.2 方案比选 ...................................................................................................................... 4
2.3 定线 ................................................................................................................................. 4 第三章 道路平面设计 .............................................................................................................. 5 3.1 概述 ................................................................................................................................. 5 3.2 平面线形设计 ................................................................................................................. 5 3.3 直线 ................................................................................................................................. 6 3.4 圆曲线 ............................................................................................................................. 6 3.5 缓和曲线 ......................................................................................................................... 7 3.6 平面线形要素 ................................................................................................................. 8 3.7 曲线主点桩号的确定 ....................................................................................................10 3.8 逐桩坐标的计算 ............................................................................................................ 11 3.9 行车视距 ........................................................................................................................13 第四章 纵断面设计 .................................................................................................................15 4.1 纵坡及坡长设计 ............................................................................................................15
4.1.1 坡长设计的一般要求 ....................................................................................................15 4.1.2 最大纵坡 .....................................................................................................................15 4.1.3 最小纵坡 .....................................................................................................................16 4.1.4 合成坡度 .....................................................................................................................16
4.2 竖曲线 ............................................................................................................................17
4.2.1 竖曲线最小半径和最小长度的确定 ...............................................................................17
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4.2.2 竖曲线计算 ..................................................................................................................18
4.3 道路平纵线形组合设计 ................................................................................................20 第五章 横断面设计 .................................................................................................................21 5.1 路肩 ................................................................................................................................21 5.2 路拱横坡度 ....................................................................................................................21 5.3 超高及加宽计算 ............................................................................................................22
5.3.1 加宽过渡 .....................................................................................................................22 5.3.2 超高值计算 ..................................................................................................................23
第六章 路基设计 .....................................................................................................................27 6.1 路基设计要求 ................................................................................................................27 6.2 路基类型 ........................................................................................................................27 6.3 路基设计内容 ................................................................................................................27
6.3.1 路基宽度 .....................................................................................................................28 6.3.2 路基高度 .....................................................................................................................28 6.3.3 路基边坡 .....................................................................................................................28 6.3.4 路基压实 .....................................................................................................................29
6.4 路基附属设施 ................................................................................................................29
6.4.1 取土坑与弃土堆 ...........................................................................................................29 6.4.2 护坡道与碎落台 ...........................................................................................................30
6.5 路基土石方计算和调配 ................................................................................................30
6.5.1 土石方计算 ..................................................................................................................30 6.5.2 土石方调配 ..................................................................................................................31
第七章 路面设计 .....................................................................................................................33 7.1 路面的选择确定 ............................................................................................................33 7.2 轴载分析 ........................................................................................................................33
7.2.1 以设计弯沉值和沥青路面沥青层层底拉应力为设计指标 ...............................................33 7.2.2 以半刚性基层层底拉应力作为设计指标 ........................................................................35
7.3 设计指标的确定 ............................................................................................................36
7.3.1 拟定路面结构 ..............................................................................................................36 7.3.2 确定土基回弹模量 .......................................................................................................36
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7.3.3 设计弯沉值和结构强度系数 .........................................................................................36
7.4 路面结构厚度计算 ........................................................................................................38 7.5 竣工验收弯沉值和层底拉应力计算 ............................................................................39 第八章 排水设计 .....................................................................................................................41 8.1 概述 ................................................................................................................................41 8.2 路基排水 ........................................................................................................................41
8.2.1 边沟 ............................................................................................................................42 8.2.2 排水沟 .........................................................................................................................42
8.3 路面排水 ........................................................................................................................43 第九章 工程概预算 .................................................................................................................45 9.1 概述 ................................................................................................................................45 9.2 概预算编制 ....................................................................................................................45 9.3 概算的计算 ....................................................................................................................46 第十章 专题：灌浆法处理软土地基 .....................................................................................47 10.1 项目概况 ......................................................................................................................47 10.2 灌浆加固机理 ..............................................................................................................47 10.3 灌浆设计 ......................................................................................................................48
10.3.1 灌浆设计的基本要求 ..................................................................................................48 10.3.2 灌浆施工....................................................................................................................49
10.4 特殊情况下的技术处理 ..............................................................................................50 10.5 注浆效果的检验与评价 ..............................................................................................51 结 论 .......................................................................................................................................53 参考文献 ...................................................................................................................................54 致 谢 .......................................................................................................................................55
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