角洞水库大桥——钢筋混凝土箱形拱桥设计

摘要

角洞水库大桥为广(州)惠(州)高速公路小金口至凌坑段的重要桥梁，跨越惠州市角洞水库区，桥址位于角洞水库两岸两个突出的山嘴之间。桥址区域属丘陵地貌、地势起伏、木林茂盛、植被良好。

根据基本设计资料，初步拟定了连续梁桥、连续刚构桥和拱桥三个方案。经综合比较，最终选择拱桥为设计方案。全桥由一跨跨越水库的拱桥及两端引桥组成，拱桥的净跨径为120m，矢跨比为1/7。主拱圈截面采用箱形截面，拱上建筑为全空腹式，腹孔墩为钢筋混凝土柱式墩，腹孔及引桥上部结构均采用标准跨径13m的预制空心板，墩、台均采用桩基础。

主拱采用悬链线作为拱轴线，运用“五点重合法”确定拱轴系数。根据确定的拱轴系数查阅公路桥涵设计手册—拱桥(上册)相关表格计算主拱各截面内力，完成主拱验算。下部结构，桩基础采用m法计算桩基内力与位移，计算截面配筋，确定单桩容许承载力，验算地基承载力。

经验算，各项指标均满足设计要求。

关键词：拱桥拱轴系数矢跨比桩基础

Abstract

JiaoDong reservoir Bridge is a important bridge of Xiaojinkou to Lingkeng of GuangHui highway,which acrossing the reservoir of HuiZhou City.The bridge is located between tow protruding gaps.Bridge site belong to hilly ground,and the surface relief is fluctuate,forests is thick, vegetation is fine.

Based on the design data,drawing up three projects which are continuous beam bridge,continuous rigid-frame bridge,and arch epared with the projects overall,and then choosed the project of arch bridge.The bridge is consisted of arch brigde that acrossed the reservoir by a single-span and the approach bridge.The length of the arch bridge’s clear span is 120 miters,and rise-span ratio is first seven.The main arch ring section is box section,spandrel structure adopt to open spandrel pier column which are made of reinforced concrete,approach bridge main beam adopt to precast cellular stab bridge that standard span is 13 miters,pier and abutment used to pile foundation.

The arch axis of main arch is catenarian line,then determine the arch axis coefficlent by the method of five points-comebine.Based on the arch axis coefficlent refered to corresponding forms which in the Design Handbook of Highway Bridge and Culverts,calculating sectional stress of main arch ring,then finished the verify of arch bridge.Calculating the pile shaft internal force and displancements by the method of “m”.Arranged the reinforcements for the piles,determined the pile bearing capacity,checked bearing capacity of foundation soil. These indexes are conform to design code by calculating finally.

Keywords: arch bridge arch axis coefficlent rise-span ratio pile foundation

目录

第一章桥型方案比选 (1)

1.1设计桥型的确定 (1)

1.2方案比选 (1)

第二章推荐方案尺寸拟定 (4)

2.1方案简介 (4)

2.2截面尺寸拟定 (4)

2.3桥面铺装 (5)

2.4主要材料 (5)

2.5施工方式 (5)

第三章拱上建筑计算 (6)

3.1 腹孔上部结构恒载计算 (6)

3.1.1空心板毛截面几何特性计算 (6)

3.1.2空心板自重 (7)

3.1.3桥面系自重 (7)

3.2盖梁计算 (8)

3.2.1盖梁恒载内力计算 (8)

3.2.2盖梁上的可变荷载计算 (10)

3.3盖梁内力计算 (20)

3.3.1各截面弯矩计算 (20)

3.3.2各截面剪力计算 (21)

3.3.3各截面内力汇总 (22)

3.3.4内力组合 (23)

3.4截面配筋设计与承载力校核 (25)

3.4.1正截面抗弯承载能力计算 (25)

3.4.2腹筋与箍筋设计 (29)

3.4.3斜截面抗剪能力验算 (31)

3.4.4盖梁裂缝宽度验算 (34)

第四章腹孔立柱设计 (36)