CAJ | 학술논문

湿喷混凝土技术逐渐被应用于高寒矿区破碎岩体巷道支护中，而温度对湿喷混凝土强度发展起着关键作用。针对吉林金英金矿寒区湿喷混凝土支护中遇到的喷层强度低、易开裂等问题，综合研究了温度、水泥掺量、水灰比对喷层强度发展响应规律，采用SEM对湿喷混凝土微观形貌进行观察。结果表明：温度低于10℃时，湿喷混凝土早期强度显著降低，温度高于16℃时，有利于后期强度增长；水泥掺量存在临界区间，掺量大于临界区间后，湿喷混凝土强度有显著增长；水灰比对不同龄期强度发展呈互补关系，低水灰比有利于早期强度提高，高水灰比更有利于后期强度的发展；温度是影响湿喷混凝土微观结构本质因素，内部初始孔隙率及骨料界面黏结强度裂化直接影响湿喷混凝土宏观力学性能；温度低于10℃时，骨料界面因热胀系数不同易产生微裂缝。通过优化配比、改进工艺，使金英金矿日喷射量达40 m3，湿喷支护返修率降低80%。
습분혼응토기술축점피응용우고한광구파쇄암체항도지호중，이온도대습분혼응토강도발전기착관건작용。침대길림금영금광한구습분혼응토지호중우도적분층강도저、역개렬등문제，종합연구료온도、수니참량、수회비대분층강도발전향응규률，채용SEM대습분혼응토미관형모진행관찰。결과표명：온도저우10℃시，습분혼응토조기강도현저강저，온도고우16℃시，유리우후기강도증장；수니참량존재림계구간，참량대우림계구간후，습분혼응토강도유현저증장；수회비대불동령기강도발전정호보관계，저수회비유리우조기강도제고，고수회비경유리우후기강도적발전；온도시영향습분혼응토미관결구본질인소，내부초시공극솔급골료계면점결강도열화직접영향습분혼응토굉관역학성능；온도저우10℃시，골료계면인열창계수불동역산생미렬봉。통과우화배비、개진공예，사금영금광일분사량체40 m3，습분지호반수솔강저80%。
The wet shotcreting technology has been gradually applied to roadway support of fractured rock mass in extremely cold mining areas, and the temperature is critical to the strength development of wet shotcreting. This paper has introduced the low strength of spray layer, likely cracking and other problems occurred to wet shotcreting support in cold regions of Jinying Gold Mine, studied the rules of influence of temperature, cement content and water-cement ratio on the strength of spray layer, and adopted SEM to observe the microstructure of wet shotcreting. The results show that the initial strength of wet shotcreting reduces significantly when the temperature is below 10 °C, and the temperature above 16 °C is quite beneficial to the long-term strength increase; there is a critical range of cement content, and when the cement content is greater than the threshold, the strength of wet shotcreting in-creases significantly;the different water-cement ratios have a complementary effect on the strength de-velop ment of different ages, because the low water-cement ratio helps increase the initial strength, while thehigh ratio helps increase the long-term strength;the temperature plays an essential role in the microstructure of wet shotcreting, and inner initial porosity and aggregate interface bonding strength cracking directly affects the macro-mechanical properties of wet shotcreting; when the temperature is lower than 10 °C, the aggregate interface intends to have microcracks due to different coefficients of thermal expansion; the daily spray amount has reached 40 m3 and the repair rate of wet shotcreting support reduced by 80%in Jinying Gold Mine by improving mixture ratio and technology.