摘要
为了明确沥青路面裂缝的影响范围,采用落锤式弯沉仪(FWD),对路面结构损坏状况和强度状况进行全面评估,并提出了一种半刚性基层沥青路面裂缝损伤状态及影响范围的确定方法,即对裂缝两侧一定范围进行弯沉检测,根据检测点距离裂缝的距离及其弯沉值所绘制的弯沉曲线准确判断裂缝影响范围及其损伤状态。对横向裂缝、单独裂缝等表面裂缝弯沉变化情况以及带不同病害程度下弯沉响应分析,发现裂缝对弯沉的影响范围为距离缝中心±50 cm范围,且弯沉值随着荷载增大而增大;裂缝中心处被认为影响最为严重,超出该范围后裂缝对于弯沉的影响数值逐渐降低。对裂缝处的当量回弹模量进行分析,发现裂缝会明显影响沥青路面的当量模量使其处于较高的水平,但不同的裂缝位置所测得的当量回弹模量衰减程度大相径庭,从养护处置角度思考,进行道路改造时不能简单采用当量模量平均值,应该考虑最薄弱环节的处理方法。该方法解决了目前沥青路面裂缝影响范围外观观测判定不准的问题,为道路路面养护维修决策制订提供精准、有效、经济的依据。
In order to clarify the influence range of asphalt pavement cracks,the damage and strength statuses of pavement structure are comprehensively evaluated by using FWD.A method for determining the damage status and influence range of semi-rigid base asphalt pavement cracks is proposed,that is,to detect the deflection on a certain range on both sides of the crack,and to accurately judge the influence range and damage status of the crack according to the deflection curve drawn by the distance between the detection point and the crack and deflection values.The deflection changes of surface cracks such as lateral cracks and individual cracks and the deflection response under different disease degrees are analyzed.It is found that(1)the influence range of the crack on the deflection is within±50 cm from the crack center,and the deflection value increases with the increase of load;(2)the crack center is considered to have the most serious influence,and the influence of cracks on deflection gradually decreases beyond this range.The analysis result of the equivalent modulus resilience at cracks shows that(1)cracks will obviously affect the equivalent modulus of asphalt pavement to make it at a higher level,but the measured attenuation of the equivalent modulus of different crack positions are quite different;(2)from the perspective of maintenance and disposal,the average value of the equivalent modulus cannot be simply used when carrying out road reconstruction,and the treatment method of the weakest link should be considered.This method solves the current problem of inaccurate determination of the appearance of the influence range of asphalt pavement cracks,and provides a accurate,effective and economical basis for road pavement maintenance decision-making.
作者
李霖
江睿南
LI Lin;JIANG Rui-nan(China Academy of Transportation Science,Beijing 100029,China)
出处
《公路交通科技》
CAS
CSCD
北大核心
2021年第7期17-21,共5页
Journal of Highway and Transportation Research and Development
关键词
道路工程
弯沉值
无损检测
等距测定
裂缝
road engineering
deflection value
nondestructive testing
isometric determination
crack
