季节性冻土地区公路路基动应力测试

Subgrade Dynamic Stress Test on Highway in Seasonal Frozen Soil Area

针对超载及冻土性质引起的路基冻胀翻浆问题，通过现场实测，对G109公路在重型交通车辆作用下，对不同深度、不同载重、不同车速的路基动态响应规律进行了研究，并对公路沿线的路基动态响应状态数据进行了长期观测，以便为室内试验和理论分析提供依据。研究结果表明：同一测点路基动应力极值在竖向上随深度的增加呈明显衰减趋势；车辆超载现象导致路基动应力增长趋势较为明显，对于载重车辆而言，后轮下的动应力响应比前轮增长更为明显；随着车速增加，路基动应力有所变化，其与路面状况相关，应综合考虑车辆冲量和实际路基平整度2个方面；通过对现场车辆的土动应力实测数据统计分析，得到该路段公路路基土动应力取值范围为0～100kPa。

Aimed at frost heaving and frost boiling issues caused by overloading and the nature of seasonal frozen soil, through field measurement on G109 under heavy transport vehicles, the dynamic response of subgrade under the influence of different load, different depths and different speeds was studied, and long term observation data of the dynamic response of the subgrade were collected in order to provide the basis for the laboratory test and theoretical analysis. The results show that subgrade dynamic stress shows a decreasing trend with the increase of depth, and with the increase of vehicle load, subgrade dynamic stress increasing trend is more obvious. The phenomenon is more apparent under the rear axle load than that under the front axle load. In terms of speed, subgrade dynamic stress will change, which is associated with the road conditions, so both impulse and roadbed roughness level should be considered. On-site vehicle soil dynamic stress statistical data show that the range of the dynamic stress is 0-100 kPa.