表面设置防火涂料高强混凝土的高温爆裂

Explosive Spalling of High Strength Concrete Coated with Fire Retardation Coating at High Temperatures

通过4组28d抗压强度为82.6MPa且外包不同厚度非膨胀型隧道防火涂料的高强混凝土试块的高温试验,研究了其爆裂状况随防火涂料厚度的变化情况.结果表明:当防火涂料厚度为20mm时,高强混凝土试块均未发生高温爆裂,试块表面所经历的最高温度仅369～405℃;当防火涂料厚度为10mm时,高强混凝土试块均发生了较剧烈的高温爆裂.与其他方法相比,采用非膨胀型隧道防火涂料不仅可有效抑制高强混凝土的高温爆裂,同时施工方便、适应性好.

With the extensive use of high strength concrete（HSC） and frequent occurrence of fire in recent years,it is necessary to find a feasible measure to inhibit explosive spalling of HSC at high temperature. Four groups of HSC specimens with 28 d cubic compressive strength of 82.6 MPa and coated with non-intumescent tunnel fire retardation coating were tested at elevated temperatures,and the influence of thickness of the coating on the explosive spalling of HSC was investigated.Test results show that：（a）the specimens coated with fire retardation coating with a thickness of 20 mm do not spall at high temperatures,and the maximum surface temperatures of these specimens are only 369 -405℃;and（b）the specimens coated with the coating with a thickness of 10 mm spall to a great extent.In comparison with other measures, non-intumescent tunnel fire retardation coating is not only effective for inhibition of explosive spalling of HSC at elevated temperatures,but also convenient for construction and feasible for various situations.