山区公路高填方涵洞减载方法及试验研究

提出了高填方涵洞加筋减载方法及加筋桥减载概念,用模型试验证明了高填方涵管加筋减载的有效性、加筋减载的合理布筋方式、影响加筋减载效果的因素。试验结果表明,应用加筋桥减载结构可在高填方涵洞上方形成一个结构明确而较稳定的卸荷结构-“加筋桥”,通过加筋桥的承载作用,有效地把涵顶的垂直土压力传递到涵台外的填土上,从而达到减载目的。采用数值模拟计算方法研究了加筋减载的力学机理,通过现场试验证明了加筋减载的良好效果。试验研究结果表明,高填方涵管加筋减载方法具有机理明确、施工操作简便、质量易于保证,安全可靠的特点。这种减载方法不但适用于高填方涵洞,而且适用于其他各种填埋式地下洞室的减载。

LOAD REDUCTION METHOD AND EXPERIMENTAL STUDY FOR CULVERTS WITH THICK BACKFILLS ON ROADWAYS IN MOUNTAINOUS REGIONS

Presented in this paper are a method of reinforcement load reduction for highway culverts under high fills and a new concept of reinforcement load reduction bridge.In the presented method,a bridge consisting of reinforcements and a ditch filled with unpacked soil and packed soil around the ditch are built over the culvert to reduce the vertical earth pressure on the top of the culvert.The mechanism of reinforcement load reduction bridge results from the deflection and anchorage action of the reinforcements,i.e.,as the soil is filled on the top of the culvert,the reinforcements will deflect and the vertical earth pressure is borne by the deflected reinforcements and then transported to the packed soil around the ditch through the anchorage action of the reinforcements.The effect of reinforcement load reduction is demonstrated by model and field tests of a concrete slab.