基于贯入阻力测试系统的聚氨酯混凝土压实时机确定方法

为了解决实际工程中聚氨酯混凝土因强度形成影响因素多而导致压实时机难以确定的问题，提出一种便捷直观的压实时机确定方法。首先针对自主研发的聚氨酯混凝土设计了一种贯入阻力测试系统，将容许空隙率（1.5%~4.0%）作为压实效果评价标准，通过重复性试验确定可压实贯入阻力范围值，提出以聚氨酯混凝土贯入阻力量化其固化反应程度的方法，进一步建立以催化剂用量为唯一可控因素的施工可压实时间预测模型。试验结果表明：在温度、湿度及催化剂用量代表性组合的试验条件下，当聚氨酯混凝土的贯入阻力在可压实贯入阻力值范围（0.20 kN±0.03 kN）内时，其马歇尔试件空隙率可满足容许空隙率（1.5%~4.0%）范围要求，相应的可压实时间预测模型相关系数高（R²=0.89）且差异性极显著。工程实例验证了该方法的可行性及可靠性。

Determination of Polyurethane Concrete Compaction Timing Based on Penetration Resistance Test System

Determining the polyurethane concrete compaction timing is difficult owing to factors that affect strength formation during construction. In this study, a convenient and intuitive method was developed for determining the compaction timing. First, a penetration resistance test system was designed, and the allowable void ratio (1.5%-4.0%) was used as the evaluation standard for the compaction timing effect. The repeatable test was performed to determine the range of the compaction timing penetration resistance. A method for quantifying the degree of curing reaction was established using the penetration resistance of polyurethane concrete, and a compaction timing prediction model was developed with the catalyst amount as the only variable. Test results show that under the test conditions of a representative combination of temperature, humidity, and catalyst amount. When the penetration resistance of polyurethane concrete is within the range of the compressible penetration resistance (0.20 kN±0.03 kN), the void ratio of its Marshall test specimen meets the requirements of the allowable void ratio (1.5%-4.0%). The corresponding compaction timing prediction model has a high correlation coefficient (R²=0.89) and a significant difference. Finally, the feasibility and reliability were verified using an engineering example.