近期由于浙江沿海限制生态功能保护区和自然保护区内的矿产资源开采,导致温岭地区集料供应紧缺,为了实现市政道路造价和性能双优,在设计阶段进行相关集料替代研究,经必选确定辉绿岩进行玄武岩的替代,本研究结合工程案例,选取了构造深度和摆值两个指标,以辉绿岩沥青磨耗层的抗滑和耐磨性能进行分析。首先以为了实现更好的抗磨耗性能,以及后期的抗滑效为原则,选取了磨耗层专用级配,对原材料进行了检测,同时对配合比设计进行了研究,确定了适用的矿料级配,确定了最佳沥青用量;混合料方面进行了辉绿岩和玄武岩所制备的沥青混合料的性能对比,并拟合其抗滑性能的衰减曲线;最后通过室内外试验分析施工现场沥青路面构造深度和摆值的检测结果,结果显示辉绿岩沥青磨耗层是满足路面抗滑要求的。 Recently, due to the limited exploitation of mineral resources in the ecological function reserve and nature reserve along the coast of Zhejiang Province, the aggregate supply in Wenling area is in short supply. In order to achieve the double optimization of municipal road cost and performance, relevant aggregate substitution research is carried out at the design stage. After selection, diabase is selected to replace basalt. In this study, combined with engineering cases, structural depth and swing value are selected as two indicators. This paper focuses on the research on the skid resistance and wear resistance of the anti sliding pavement of diabase asphalt pavement. Firstly, in order to achieve better anti wear performance and later anti slip effect, a special grading for the wearing layer was selected, and raw materials were tested. At the same time, the mix design was studied to determine the suitable mineral aggregate grading and the optimal asphalt dosage; In the aspect of mixture, the performance of asphalt mixture prepared by diabase and basalt is compared, and the attenuation curve of its anti sliding performance is fitted; Finally, through indoor and outdoor tests to analyze the detection results of the construction site asphalt pavement structure depth and swing value, the results show that the diabase asphalt wearing course meets the requirements of pavement anti sliding.
近期由于浙江沿海限制生态功能保护区和自然保护区内的矿产资源开采,导致温岭地区集料供应紧缺,为了实现市政道路造价和性能双优,在设计阶段进行相关集料替代研究,经必选确定辉绿岩进行玄武岩的替代,本研究结合工程案例,选取了构造深度和摆值两个指标,以辉绿岩沥青磨耗层的抗滑和耐磨性能进行分析。首先以为了实现更好的抗磨耗性能,以及后期的抗滑效为原则,选取了磨耗层专用级配,对原材料进行了检测,同时对配合比设计进行了研究,确定了适用的矿料级配,确定了最佳沥青用量;混合料方面进行了辉绿岩和玄武岩所制备的沥青混合料的性能对比,并拟合其抗滑性能的衰减曲线;最后通过室内外试验分析施工现场沥青路面构造深度和摆值的检测结果,结果显示辉绿岩沥青磨耗层是满足路面抗滑要求的。
辉绿岩,沥青磨耗层,构造深度,摆值
Qinghao Zhu
Shanghai Construction Design & Research Institute Co., Ltd., Shanghai
Received: Jun. 11th, 2023; accepted: Jul. 2nd, 2023; published: Jul. 13th, 2023
Recently, due to the limited exploitation of mineral resources in the ecological function reserve and nature reserve along the coast of Zhejiang Province, the aggregate supply in Wenling area is in short supply. In order to achieve the double optimization of municipal road cost and performance, relevant aggregate substitution research is carried out at the design stage. After selection, diabase is selected to replace basalt. In this study, combined with engineering cases, structural depth and swing value are selected as two indicators. This paper focuses on the research on the skid resistance and wear resistance of the anti sliding pavement of diabase asphalt pavement. Firstly, in order to achieve better anti wear performance and later anti slip effect, a special grading for the wearing layer was selected, and raw materials were tested. At the same time, the mix design was studied to determine the suitable mineral aggregate grading and the optimal asphalt dosage; In the aspect of mixture, the performance of asphalt mixture prepared by diabase and basalt is compared, and the attenuation curve of its anti sliding performance is fitted; Finally, through indoor and outdoor tests to analyze the detection results of the construction site asphalt pavement structure depth and swing value, the results show that the diabase asphalt wearing course meets the requirements of pavement anti sliding.
Keywords:Diabase, Asphalt Wearing Course, Structural Depth, Pendulum Value
Copyright © 2023 by author(s) and beplay安卓登录
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市政道路表面通常会铺筑磨耗层,其作用是为轮重的反复作用提供功能层,抗滑耐磨性决定路面的运行状况和行车安全。以往玄武岩碎石多作为粗骨料使用,但随着开采量的限制,玄武岩碎石单价大幅上涨,运输距离超出可接受范围,更有甚者会造成工程延误 [
本次研究依托实体工程,即温岭市横峰大道工程,该项目西接疏港公路向东敷设,城市主干路双向6车道,西侧跨越VII级航道江厦大港、下穿市域轨道S1线,东侧跨越VII级航道前洋河,总长1.075 km,红线宽度为50 m,设计时速50 km/h。工程所处浙江台州沿海,为了环保的推进,相关部分对沿海区域矿山资源进行了限制开采的措施,随之区域内玄武岩集料出现一定程度的短缺和匮乏,周边可供替代的有辉绿岩和石灰岩等。
经初步调研发现该地区及其周边的石灰石集料的强度无法达标,因此考虑在沥青路面使用辉绿岩进行沥青磨耗层的设计,磨耗层设计厚度为4 cm。严格原材料选择和配合比设计施工前进行。虽然替代玄武岩可以显着节省施工成本,但辉绿岩的硬度和耐久性与玄武岩相比存在一定的劣势 [
以提高磨耗层沥青混凝土的高温稳定性为目标,尽可能的降低车辙病害的出现,这次工程项目和本次试验研究均选取了上海城建日沥特种沥青公司生产的SBS改性沥青。它的主要技术指标经检测后如表1所示。其性能均满足规范 [
测试项目 | SBS改性沥青 |
---|---|
针入度(25℃, 100 g, 5 s) (0.1 mm) | 51.3 |
软化点(℃) | 78.2 |
延度5℃ (cm) | 34.2 |
135℃粘度(Pa∙s) | 2.40 |
177℃粘度(Pa∙s) | 0.77 |
表1. 试验和项目用SBS改性沥青主要技术指标
经过筛选,最终选用了浙江省仙居采石场的辉绿岩碎石。质地坚硬,强度高,不含杂质,风化颗粒,形状规则,呈立方体。是一种优质玄武岩代替骨料,其他的添加剂选取了为硅酸盐水泥。
来料粗骨料样品送实验室进行筛分试验,为了实现更好的抗磨耗性能,以及后期的抗滑效果,适当增加粗集料的用量,且添加少量水泥取代一半的矿粉,以此为原则研发新型沥青路面WS-13抗滑磨耗层(Wearing Surface-13),结合项目现有集料的合成级配如图1所示,其中红线为下限,蓝线为上限,绿线为本次合成的WS-13实际用到的级配。
图1. 沥青路面WS-13抗滑磨耗层级
选择3.5%~5.5%的5种沥青混合料配制马歇尔试验用沥青混合料,经过常规的马歇尔试验结果最终确定最佳沥青混合比为4.8%。
两种集料均出现在本次试验中,即辉绿岩和玄武岩,选用同样的WS-13级配制备生成沥青混合料。采用铺砂法检测路面磨耗层的结构深度,两种混合料的结构深度衰减曲线如图2所示。
图2. 两种混合料构造深度及其拟合情况
构造深度检测结果经过拟合得出多形式拟合置入图中。从趋势线可以看出,当累计作用达35~38万次之后,辉绿岩和玄武岩的WS-13混合料都趋向于平缓,从趋势线来看两者表现出差距稳定在0.5 mm左右,在100万次以内,辉绿岩WS-13的构造深度可达0.65 mm,这是满足规范 [
选用摆氏仪测定摆值,经试验结果绘制两种混合料摆值衰减曲线如图3所示。
图3. 两种混合料摆值拟合及其拟合情况
两种沥青混合料的摆值检测结果与构造深度有很大的差异。但其差值基本上是一致的,均在5~15个BPN之间。这是在加载次数已经足够大时,由于辉绿岩的强度略低于玄武岩,摆值衰减速度较快,差值最大时可达15 BPN,但标准荷载作用次数由20万次左右时,两者差距仅5BPN,辉绿岩WS-13达到了68 BPN,满足规范 [
为了对比室内外效果差异,研究选取了利用试验段进行实际检测。抗滑性能测试点为试验段现场选取,采用手工铺沙法测定构造深度和摆值仪方法测定抗滑性能。试验结果如图4和图5所示。
图4. 磨耗层表面摆值检测值
图5. 磨耗层表面构造深度检测值
从图4可以看出工程试验段所有断面的摆值的检测显示抗滑值BPN最大值为68左右,最小值为66左右,均大于规范要求 [
基于温岭市横峰大道路沥青路面磨耗层示范工程,试验研究结果如下:
1) 实现更好的抗磨耗性能,以及后期的抗滑效果,适当增加粗集料的用量,且添加少量水泥取代一半的矿粉,经过合理的配合比设计,研究者提出了WS-13级配的概念,以应对辉绿岩替代玄武岩的沥青磨耗层成为专用级配;
2) 在结构深度衰减规律分析中,WS-13辉绿岩与玄武岩沥青混合料结构深度的深度衰减率基本一致,衰减与路面材料压实程度有关,辉绿岩作为集料通过合理设计是可以满足沥青路面的抗滑要求;摆值中两种沥青混合料的衰减率在加载初期均较高,后期逐渐减慢并趋于稳定。两者相差不大,WS-13辉绿岩达到了68BPN,整体测试可以满足设计要求。
3) 通过现场示范路段的防滑值和结构深度检测结果可以看到,随机选取的三个断面的防滑值和结构深度检测结果的平均值为高于规范要求值,说明用辉绿岩替代防滑涂料的防滑沥青路面也能满足现场的要求。
朱庆浩. 辉绿岩替代型沥青磨耗层的试验研究Experimental Investigation on Asphalt Wearing Course Substituted by Diabase[J]. 土木工程, 2023, 12(07): 949-954. https://doi.org/10.12677/HJCE.2023.127108