岩石力学与工程学报
巖石力學與工程學報
암석역학여공정학보
CHINESE JOURNAL OF ROCK MECHANICS AND ENGINEERING
2014年
8期
1711-1719
,共9页
李国维%余亮%吴玉财%贺冠军%戴剑%刘龙%阿曼努
李國維%餘亮%吳玉財%賀冠軍%戴劍%劉龍%阿曼努
리국유%여량%오옥재%하관군%대검%류룡%아만노
边坡工程%纤维增强聚合物筋%喷砂筋%预应力%循环荷载%黏结损伤%光栅监测
邊坡工程%纖維增彊聚閤物觔%噴砂觔%預應力%循環荷載%黏結損傷%光柵鑑測
변파공정%섬유증강취합물근%분사근%예응력%순배하재%점결손상%광책감측
slope engineering%FRP bars%sand-coated bars%prestress%cyclic loading%bond damage%fiber Bragg grating sensing
纤维增强聚合物(FRP)可替代钢筋用于边坡加固来解决锚杆耐久性问题。FRP筋模量较小,为限制加固体的前期变形,需对其施加预应力。采用预应力施加装置完成循环加荷,光栅传感技术监测杆体应变,研究预应力施加及循环荷载下喷砂GFRP锚杆的黏结性能。研究表明,施加预应力使锚杆结构承受的过载会导致锚杆体界面黏结力损伤,同级荷载多次循环产生的损伤效应相对于过载的影响可以忽略不计;喷砂GFRP锚杆的黏结力损伤仅受过载的影响,与当前运行荷载无关;喷砂GFRP锚杆体上不同位置的界面剪力,在剪力较小时由黏结力承担,剪力较大时黏结力完全丧失转由摩阻力承担;喷砂GFRP锚杆加固结构承受峰值荷载过大后会导致黏结损伤造成锚固结构松动;预应力喷砂GFRP锚杆结构的超张荷载需超过运行荷载一定量值,以保障运行期锚固力稳定。
纖維增彊聚閤物(FRP)可替代鋼觔用于邊坡加固來解決錨桿耐久性問題。FRP觔模量較小,為限製加固體的前期變形,需對其施加預應力。採用預應力施加裝置完成循環加荷,光柵傳感技術鑑測桿體應變,研究預應力施加及循環荷載下噴砂GFRP錨桿的黏結性能。研究錶明,施加預應力使錨桿結構承受的過載會導緻錨桿體界麵黏結力損傷,同級荷載多次循環產生的損傷效應相對于過載的影響可以忽略不計;噴砂GFRP錨桿的黏結力損傷僅受過載的影響,與噹前運行荷載無關;噴砂GFRP錨桿體上不同位置的界麵剪力,在剪力較小時由黏結力承擔,剪力較大時黏結力完全喪失轉由摩阻力承擔;噴砂GFRP錨桿加固結構承受峰值荷載過大後會導緻黏結損傷造成錨固結構鬆動;預應力噴砂GFRP錨桿結構的超張荷載需超過運行荷載一定量值,以保障運行期錨固力穩定。
섬유증강취합물(FRP)가체대강근용우변파가고래해결묘간내구성문제。FRP근모량교소,위한제가고체적전기변형,수대기시가예응력。채용예응력시가장치완성순배가하,광책전감기술감측간체응변,연구예응력시가급순배하재하분사GFRP묘간적점결성능。연구표명,시가예응력사묘간결구승수적과재회도치묘간체계면점결력손상,동급하재다차순배산생적손상효응상대우과재적영향가이홀략불계;분사GFRP묘간적점결력손상부수과재적영향,여당전운행하재무관;분사GFRP묘간체상불동위치적계면전력,재전력교소시유점결력승담,전력교대시점결력완전상실전유마조력승담;분사GFRP묘간가고결구승수봉치하재과대후회도치점결손상조성묘고결구송동;예응력분사GFRP묘간결구적초장하재수초과운행하재일정량치,이보장운행기묘고력은정。
The durability problem of anchor rods used to reinforce slopes can be solved by substituting fiber reinforced polymer(FRP) bars for steel bars. The FRP bars have small elastic moduli,and therefore should be prestressed in order to limit the deformation of the reinforced slope during its service stage. This paper described the grating sensing technology to be applied to monitor the bond behavior of sand-coated GFRP anchor rod under cyclic prestressing. The results showed that prestressing of the sand-coated GFRP anchor rod led to the damage of rod-mortar interface bonding of the anchor. The effect of repeated load on the bonding was negligible and the effect of the surcharge load was significant. The damage to the bonding of rod-mortar interface of the anchor is dependent only on the surcharge load,and not on the service load. The shear force of the anchor rod is provided by the bonding force and friction;with the bonding force generated at the initial stage,and then changed into friction at the later stage. The excessive peak loading leads to the damage to the bonding and the loosening of the anchor structure. The over tension load of the prestressed anchor rod structure must exceed the service load to an extent in order to ensure a stable anchorage force in the service stage.