风化岩层锚杆临界锚固长度原位试验研究
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摘要
通过在大连地区典型的强风化板岩和强化辉绿岩中开展锚杆现场拉拔试验,分析该风化岩层中锚杆锚固段长度对极限抗拔承载力及锚固段与风化岩层界面间剪应力规律的影响,研究了大连地区典型风化岩层锚杆的临界锚固长度。结果表明,强风化板岩和强化辉绿岩界面的剪应力极限值基本一致;试验短锚杆具有较高的承载力,而长锚杆的极限抗拔承载力增加十分有限,仅仅依靠增长锚固段长度来获得更高的极限抗拔承载力是不合理的;锚杆基本试验应充分考虑锚固段长度的影响;实际工程中,强风化板岩和强化辉绿岩的锚杆临界锚固长度可取3.5m和4.0m。本文的研究结论对大连地区及风化岩层地区的锚杆设计,都具有很好的学术研究价值和工程应用价值。
The on-site pull-out test of bolts was performed in typical weathered slate and reinforced diabase in the Dalian area. The length of the anchoring section of the anchored rock in the weathered rock layer was analyzed for the ultimate pull-out capacity and the interface between the anchor section and the weathered rock formation. Based on the influence of stress law,the critical anchoring length of bolts of typical weathered rock in Dalian was studied. The results show that limit shear stress on the interface between grouting body and strongly weathered rock of slate and diabase. The short anchors possess high bearing capacity,and the increase of ultimate uplift bearing capacity of long anchor was very limited. It was not reasonable to obtain higher anti uplift capacity by increasing anchorage length only. Basic test of anchor should fully consider the effect of anchorage length. The value of critical anchorage length of anchor in the strongly weathered rock of slate and diabase could be determined to 3.5 m and 4.0 m respectively. Research conclusions of this article have great value in academic research and engineering application for anchor design in Dalian city and region of weathered rock.
The on-site pull-out test of bolts was performed in typical weathered slate and reinforced diabase in the Dalian area. The length of the anchoring section of the anchored rock in the weathered rock layer was analyzed for the ultimate pull-out capacity and the interface between the anchor section and the weathered rock formation. Based on the influence of stress law,the critical anchoring length of bolts of typical weathered rock in Dalian was studied. The results show that limit shear stress on the interface between grouting body and strongly weathered rock of slate and diabase. The short anchors possess high bearing capacity,and the increase of ultimate uplift bearing capacity of long anchor was very limited. It was not reasonable to obtain higher anti uplift capacity by increasing anchorage length only. Basic test of anchor should fully consider the effect of anchorage length. The value of critical anchorage length of anchor in the strongly weathered rock of slate and diabase could be determined to 3.5 m and 4.0 m respectively. Research conclusions of this article have great value in academic research and engineering application for anchor design in Dalian city and region of weathered rock.
引文
[1]黄子平,Einar Broch,吕明.水电站地下厂房洞室顶拱的形成与锚固[J].岩石力学与工程学报,2005,24(8):1348-1354.
[2]周勇,朱彦鹏.框架预应力锚杆支护结构中锚杆长度的研究[J].地下空间与工程学报,2008,4(3):406-410.
[3]张金龙,徐卫亚,徐飞,等.深卸荷变形拉裂岩体锚索预应力损失规律研究[J].岩石力学与工程学报,2009,28(S1):3965-3970.
[4]张发明,刘汉龙,赵维炳.预应力锚索加固岩质边坡的设计实例[J].岩土力学,2000,21(2):177-179.
[5]康红普,王金华,林健.煤矿巷道锚杆支护应用实例分析[J].岩石力学与工程学报,2010,29(4):649-664.
[6]马海春,胡崔可锐,查甫生,等.锚杆受力特点理论研究[J].地下空间与工程学报,2016,12(S1):44-48.
[7]刘永权,刘新荣,杨忠平,等.不同类型预应力锚索锚固性能现场试验对比研究[J].岩石力学与工程学报,2016,35(2):275-283.
[8]陈昌富,梁冠亭,汤宇,等.锚杆锚固体与土体界面特性室内测试新方法[J].岩土工程学报,2015,37(6):1115-1122.
[9]郭锐剑,堪文武,段建,等.考虑界面软化特性的土层锚杆拉拔受力分析[J].中南大学学报:自然科学版,2012,43(10):4003-4009.
[10]Kim N,Park J,Kim S.Numerical Simulation of Ground Anchors[J].Computers and Geotechnics,2007,34(6):498-507.
[11]Phillips S H E.Factors Affecting the Design of Anchorages in Rock[R].London:Cementation Research Ltd.,1970.
[12]Kilic A,Yasar E,Atis C D.Effect of Bar Shape on the Pullout Capacity of Fully Grouted Rock Bolts[J].Tunnelling and Underground Space Technology,2003,18(1):1-6.
[13]徐前卫,朱合华,金方方,等.软弱破碎岩体中锚杆抗拔受力机理及试验研究[J].地下空间与工程学报,2011,7(5):830-835.
[14]张幼振,石智军,张晶.岩石锚杆锚固段荷载分布试验研究[J].岩土力学,2010,31(S2):184-188.
[15]曾宪明,赵林,李世民,等.锚固类结构杆体临界锚固长度与判别方法试验研究[J].岩土工程学报,2008,30(S1):404-409.
[16]张洁,尚岳全,叶彬.锚杆临界锚固长度解析计算[J].岩石力学与工程学报,2005,24(7):1134-1138.
[17]龙照,赵明华,张恩详,等.锚杆临界锚固长度简化计算方法[J].岩土力学,2010,31(9):2991-2995.
[18]GB50086-2015,岩土锚杆与喷射混凝土支护工程技术规范[S].
[19]GB 50330-2013,建筑边坡工程技术规范[S].
[20]JGJ/T 401-2017,锚杆检测与监测计算规程[S].
[2]周勇,朱彦鹏.框架预应力锚杆支护结构中锚杆长度的研究[J].地下空间与工程学报,2008,4(3):406-410.
[3]张金龙,徐卫亚,徐飞,等.深卸荷变形拉裂岩体锚索预应力损失规律研究[J].岩石力学与工程学报,2009,28(S1):3965-3970.
[4]张发明,刘汉龙,赵维炳.预应力锚索加固岩质边坡的设计实例[J].岩土力学,2000,21(2):177-179.
[5]康红普,王金华,林健.煤矿巷道锚杆支护应用实例分析[J].岩石力学与工程学报,2010,29(4):649-664.
[6]马海春,胡崔可锐,查甫生,等.锚杆受力特点理论研究[J].地下空间与工程学报,2016,12(S1):44-48.
[7]刘永权,刘新荣,杨忠平,等.不同类型预应力锚索锚固性能现场试验对比研究[J].岩石力学与工程学报,2016,35(2):275-283.
[8]陈昌富,梁冠亭,汤宇,等.锚杆锚固体与土体界面特性室内测试新方法[J].岩土工程学报,2015,37(6):1115-1122.
[9]郭锐剑,堪文武,段建,等.考虑界面软化特性的土层锚杆拉拔受力分析[J].中南大学学报:自然科学版,2012,43(10):4003-4009.
[10]Kim N,Park J,Kim S.Numerical Simulation of Ground Anchors[J].Computers and Geotechnics,2007,34(6):498-507.
[11]Phillips S H E.Factors Affecting the Design of Anchorages in Rock[R].London:Cementation Research Ltd.,1970.
[12]Kilic A,Yasar E,Atis C D.Effect of Bar Shape on the Pullout Capacity of Fully Grouted Rock Bolts[J].Tunnelling and Underground Space Technology,2003,18(1):1-6.
[13]徐前卫,朱合华,金方方,等.软弱破碎岩体中锚杆抗拔受力机理及试验研究[J].地下空间与工程学报,2011,7(5):830-835.
[14]张幼振,石智军,张晶.岩石锚杆锚固段荷载分布试验研究[J].岩土力学,2010,31(S2):184-188.
[15]曾宪明,赵林,李世民,等.锚固类结构杆体临界锚固长度与判别方法试验研究[J].岩土工程学报,2008,30(S1):404-409.
[16]张洁,尚岳全,叶彬.锚杆临界锚固长度解析计算[J].岩石力学与工程学报,2005,24(7):1134-1138.
[17]龙照,赵明华,张恩详,等.锚杆临界锚固长度简化计算方法[J].岩土力学,2010,31(9):2991-2995.
[18]GB50086-2015,岩土锚杆与喷射混凝土支护工程技术规范[S].
[19]GB 50330-2013,建筑边坡工程技术规范[S].
[20]JGJ/T 401-2017,锚杆检测与监测计算规程[S].