寒冷地区水泥稳定多孔玄武岩碎石路面基层力学性能研究

Study on the mechanical properties of cement stabilized porous basalt crushed stone pavement subgrade in cold areas

在建张尚高速路段挖方石料以多孔玄武岩为主,为节约矿产资源和工程成本,拟采用水泥稳定该碎石作为高速公路路面基层材料。经查阅资料,在寒冷地区应用水泥稳定多孔玄武岩碎石作为路面基层材料在国内外研究中都没有相关工程案例。为探究该材料作为张尚高速路面基层的可用性,进行了原材料各项性能试验并制备3%、4%和5%不同水泥剂量多孔玄武岩碎石试件,进行无侧限抗压强度试验和冻融循环试验探究该材料的力学性能。实验表明:多孔玄武岩碎石材料的吸水率和含水率远超普通碎石材料;软弱颗粒含量、压碎值和磨耗值均比较大,但仍满足路面基层原材料规范要求;5%水泥稳定材料满足路面基层强度规范要求,但经5次冻融循环后力学性能有明显下降。

According to the actual situation that the excavation stone of the under-construction Zhang Shang Expressway section is mainly porous basalt,in order to save mineral resources and project cost,it is proposed to use cement stabilized this gravel as the highway pavement subgrade material.After reviewing the data,there is no relevant engineering case in domestic and international research on the application of cement-stabilized porous basalt gravel as pavement base material in cold areas.In order to investigate the usability of this material as the pavement subgrade of Zhang Shang Expressway,various performance tests of raw materials were conducted and porous basalt crushed stone specimens with different cement contents of 3%,4%and 5%were prepared,and lateral limit compressive strength tests and freeze-thaw cycle tests were conducted to investigate the mechanical properties of this material.The experiments showed that the water absorption and water content of porous basalt crushed stone were much higher than those of ordinary crushed stone;the content of weak particles,crushing value and abrasion value were relatively large,but still met the requirements of raw material specifications for pavement subgrade;5%cement stabilized the material to meet the requirements of pavement subgrade strength specifications,but the mechanical properties decreased significantly after five freeze-thaw cycles.