共查询到19条相似文献，搜索用时 0 毫秒
1.
为探究钢-地质聚合物混凝土(geopolymer concrete, GPC)栓钉连接的界面抗剪性能,对4组栓钉连接的钢-混凝土试件进行推出试验,分析其破坏模式、荷载-滑移曲线、抗剪承载力以及延性等力学性能,得到混凝土类型、GPC抗压强度以及栓钉直径对界面黏结性能的影响规律。结果表明：GPC试件中栓钉表现出剪断破坏,与普通混凝土试件破坏形态一致,GPC翼板无明显裂缝,整体性较好;GPC栓钉抗剪承载力与普通混凝土栓钉试件相近,刚度偏低,但具有更好的延性;提高GPC抗压强度和栓钉直径可有效提高栓钉的抗剪承载力和刚度。基于实测结果,提出栓钉连接的钢-GPC抗剪承载力计算公式和界面黏结-滑移本构模型。 相似文献
2.
为了研究新型全装配式剪力墙结构体系中水平接缝的可行性及抗震性能,制作了2个试件并分别进行单调加载试验与低周反复加载试验.在试验的基础上研究了该全装配式剪力墙的荷载-位移曲线、承载能力、延性性能、抗侧刚度、钢筋应变、连接钢框的应变分布以及连接钢框与内嵌边框之间的相对滑移等.试验结果表明:试件具有较好的承载能力及延性,位移延性系数达3.7以上;在整个试验过程中,除受压端外,连接钢框中的正应力及剪应力远小于其屈服强度;试件受压端内嵌边框与连接钢框之间发生了一定的相对滑移,达1.13 mm,而受拉端二者之间未发生明显的相对滑移.该全装配式剪力墙结构体系的水平接缝安全可靠,抗震性能良好,方案可行. 相似文献
3.
《实验室研究与探索》2016,(10):7-11
通过聚丙烯纤维锂渣混凝土试件的中心拉拔试验,试验中聚丙烯纤维掺量分别为0、0.6、0.9、1.2、1.5 kg/m~3,锂渣替代水泥(质量百分数分别为0%、10%、20%、30%),共20组60个尺寸为150 mm的立方体拉拔试件。研究聚丙烯纤维锂渣混凝土与HRB500钢筋的黏结性能,分析聚丙烯纤维掺量和锂渣掺量对黏结性能的影响,并探索拉拔试件模具的制作方法。结果表明:聚丙烯纤维掺量与极限黏结强度大致成正比;随着锂渣掺量的增大,极限黏结强度呈"减小-增大-减小"的走势,锂渣掺量为20%时达到最大值;纤维掺量为0.9 kg/m~3、锂渣掺量为20%时为较优配合比,比无锂渣无纤维试件的极限黏结强度提高了32.7%。 相似文献
4.
使用通用有限元软件ABAQUS分析了钢材屈服强度、方钢管厚度、UHPC强度对高强方钢管约束UHPC短柱轴压性能的影响。首先使用ABAQUS对已有的普通钢管约束混凝土试验进行计算,结果与试验值基本一致。在此基础上建立了高强方钢管约束UHPC短柱模型,对比了不同参数下构件荷载-位移曲线、荷载-纵向应变曲线的变化特征。研究表明:构件前期刚度受混凝土强度影响很小,但由于增加混凝土强度使构件套箍系数降低,工作曲线下降段斜率增大,延性下降。钢管屈服强度的提高对构件的延性有很大改善,但对极限承载能力影响较小。核心混凝土强度是影响高强钢管约束UHPC短柱承载能力的主要因素,由于钢管不直接承担纵向荷载,仅对混凝土产生材料性能上的影响,钢管约束混凝土应看做混凝土的一种。 相似文献
5.
为研究疲劳荷载对钢桁腹-混凝土组合外接式节点静力性能的影响,设计并制作了3个1∶3节点模型,分别进行了静载破坏试验和疲劳后静载破坏试验,获得了节点破坏模式、荷载-位移曲线及节点板荷载-应变曲线,研究了节点屈服荷载、极限荷载、节点刚度及延性系数等力学性能指标的变化.试验结果表明：节点板是组合节点受力关键构件,节点板破坏是外接式节点的典型破坏模式;疲劳荷载对节点屈服前的受力性能影响较小,但对节点屈服后的受力性能影响显著;与仅承受静载的试件相比,未疲劳破坏试件的极限承载力减小4%,延性系数减小28%,有疲劳破坏试件的极限承载力减小25%,延性系数减小52%;疲劳裂纹引起了节点板应力重分布,增大了无疲劳裂纹区域的应变,且应变增长率随着与疲劳裂纹距离的增加而减小. 相似文献
6.
利用有限元软件ABAQUS对纯钢框架试件、冷弯薄壁型钢组合墙体试件、钢框架-冷弯薄壁型钢组合墙体试件、覆双面OSB板的钢框架-冷弯薄壁型钢组合墙体试件进行水平低周往复荷载作用下研究,分析了试件的滞回曲线、骨架曲线、抗侧刚度、延性和耗能等。结果表明,钢框架与冷弯薄壁型钢组合墙体有明显的组合效应;冷弯薄壁型钢组合墙体能明显增强钢框架结构的承载力、刚度、延性和耗能能力;覆双面OSB板钢框架-冷弯薄壁型钢组合墙体结构抗震性能较不覆板的钢框架-冷弯薄壁型钢组合墙体结构抗震性能好。 相似文献
7.
针对仿古建筑双梁-柱节点力学性能较差的问题,将其与黏滞阻尼器相结合,形成附设黏滞阻尼器的仿古建筑双梁-柱节点。为研究该类型试件的力学性能,共设计4个节点试件,包括1个仿古建筑单梁-柱节点对比试件和3个典型仿古建筑双梁-柱节点试件,其中2个试件为设置黏滞阻尼器的试件,1个为未设置黏滞阻尼器的试件,进行正弦波荷载快速往复加载试验,分析加载全过程中试件的破坏特性、破坏模式及钢筋应变变化,并对其恢复力曲线、骨架曲线及承载力等力学性能指标进行分析。结果表明：附设黏滞阻尼器可显著改善双梁-柱节点的力学性能,试件滞回曲线更为饱满,双梁-柱节点的极限承载能力提升16.4%～18.1%,延性系数提升13.5%～15.0%,骨架曲线下降段更为平缓。 相似文献
8.
采用Ansys有限元软件对8根不同锈蚀率的FRP片材加固钢筋混凝土梁的受弯性能进行数值分析,研究纵筋锈蚀率对FRP加固梁的裂纹开展、破坏模式、承载能力以及延性和变形能力的影响.研究结果表明:低钢筋锈蚀率的梁发生受压区混凝土压碎破坏;中等锈蚀率的梁钢筋屈服后,钢筋与混凝土界面发生黏结滑移,最后FRP剥离破坏;高锈蚀率的梁钢筋没有达到屈服强度便发生黏结滑移,最后发生受压区混凝土压碎破坏.钢筋锈蚀越严重,FRP加固钢筋混凝土梁的承载力降低得越多.试件RCB-1(锈蚀率为0)的承载力为115 kN,而试件RCB-7(锈蚀率为20%)的承载力仅为42 kN.与FRP加固未锈蚀的钢筋混凝土梁相比,FRP加固锈蚀钢筋混凝土梁的变形能力较高.试件RCB-1和试件RCB-7的最大跨中挠度分别为20 mm和35 mm,而试件RCB-5(锈蚀率为10%)的最大跨中挠度达到了60 mm. 相似文献
9.
大骨料混凝土在双轴压应力状态下的变形和强度试验研究 总被引：1，自引：0，他引：1
利用大连理工大学自行研制改造的液压伺服静、动态三轴试验系统对不同骨料级配和尺寸的混凝土试件在双向压荷载作用下的变形和强度特性进行了试验研究.试验所用试件有3种:采用大坝原级配最大骨料粒径为80 mm的立方体试件以及相应的湿筛混凝土试件,尺寸分别为250mm×250mm×250 mm,150 mm×150 mm×150 mm和100 mm×100 mm×100 mm.试验过程中,测得了所有试件两个加载方向的应力和应变,以及未加载方向上的侧向变形,并根据试验结果,系统地探讨了不同级配混凝土的双轴抗压强度、极限变形、应力-应变曲线以及破坏形态的变化规律,发现大骨料混凝土在双轴压作用下的极限强度和变形能力要比相应的湿筛小骨料混凝土提高的更多,最后分别在主应力空间和主应变空间建立了不同级配混凝土的破坏准则,这为水工大体积混凝土按多轴强度理论进行设计提供了试验依据. 相似文献
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11.
Experimental study on bonding properties between steel strand and concrete at cryogenic temperatures
To study the bonding properties between steel strand and concrete at room and cryogenic temperatures, a series of center pullout experiments were conducted on 96 bonding anchorage specimens at the lowest temperature of-165 ℃. The impacts on the bonding property of such parameters as the temperature, concrete strength, the relative concrete cover thickness, and the relative anchorage length were analyzed. The test results indicate that the changes in temperature have a clear effect on the bonding property between steel strand and concrete. As the temperature decreases, the bond stress, which corresponds to a 1 mm slip of steel strand in relation to concrete, and the ultimate bond strength initially increase and subsequently decrease at the inflection point of-80 ℃. The impact of the concrete strength on the bonding property, as shown by the tensile strength and the moisture content interaction, indicates that the bond stress vs concrete strength curve initially increases and later decreases with a decrease in temperature; the bond stress vs concrete cover thickness curve linearly increases, but the bond stress vs anchorage length curve linearly decreases at first and finally levels off. 相似文献
12.
By using semisolid joining technique,the bonding of stainless steel and semisolid aluminum alloy is successfully realized.The relationships between interracial shear strength and solid fraction of aluminum alloy,bonding pressure and time of keeping pressure were studied by the method of orthogonal experiment.The interfacial structure and the fracture structure of the bonding plate are studied by means of optical microscope (OM) and scanning electron microscope (SEM).The results show that there is the best solid fraction between the solid phase line and the liquid phase line of the semisolid aluminum alloy,with the increase of bonding pressure and pressure time,the interfacial shear strength increases rapidly,and then with further increase of bonding pressure and pressure time,the shear strength rises little.Along the interface,solid phase and liquid phase bond with stainless steel by turns because of the different diffusion ability.So,a new type of non-equilibrium diffusion interfacial structure is constructed at the interface of stainless steel and aluminum alloy,compound mechanism of plastic and brittle fracture interface was formed at the shear fracture interface. 相似文献
13.
钢桥面环氧沥青铺装的界面行为 总被引：2，自引：0，他引：2
通过引入一个新参数膜劲度,在部分共同作用原理的基础上,建立了描述钢桥面环氧沥青混凝土铺装复合梁在负弯矩作用下的界面行为模型,用以分析钢-环氧沥青混凝土之间的界面滑移与应变.推导了弹性工作状态下复合梁的界面滑移与应变的表达式,编制了数值计算程序并用2根复合梁进行了校核.然后采用该程序分析了界面滑移与应变沿复合梁纵向的分布特征,以及铺装层中的最大拉应力、层间剪应力对材料参数的敏感性.结果表明,界面效应削弱了钢桥面铺装复合梁的整体抗弯刚度;中低温条件下,采用劲度更大的粘结层材料有利于改善沥青铺装层的受力;粘结层的损伤累积将加剧沥青铺装层的破坏. 相似文献
14.
李海斌张晓波石林爽张曼婷 《福建工程学院学报》2021,(4):360-364
采用固体渗剂包埋渗法对Ti-6Al-4V钛合金进行硼-稀土共渗处理,并利用超声振动空蚀机研究分析试样在去离子水中的空蚀性能。结果表明,硼-稀土共渗在Ti-6Al-4V合金表面获得均匀致密的表面渗层。表面渗层具有很高的显微硬度,与基体冶金结合,其主要由TiB2、TiB化合物层和B原子固溶于α-Ti的扩散层构成。稀土元素La的添加,提高渗硼效率,使试样表面渗层厚度增加,显微硬度显著提高,材料的抗空蚀性能得到显著改善。 相似文献
15.
根据内置CFRP圆管的方钢管高强混凝土的特点,通过引入混凝土强度折减系数和等效约束折减系数,将内置CFRP圆管的方钢管高强混凝土等效为内置CFRP圆管的圆钢管高强混凝土。进而,在统一强度理论的基础上,推导出内置CFRP圆管的方钢管高强混凝土轴压构件的强度承载力。通过引入整体稳定系数,推导出内置CFRP圆管的方钢管高强混凝土轴压中长柱的稳定极限承载力公式。将该公式的计算结果与试验结果进行了比较,结果表明该理论公式是正确可行的。理论公式以期能为工程应用提供帮助。 相似文献
16.
Improving the Fatigue Performance of the Welded Joints of Ultra-Fine Grain Steel by Ultrasonic Peening 总被引：2，自引：0，他引：2
Contrast tests were carried out to study the fatigue performance of the butt joints treated by ultrasonic peening, aiming at the improvement of ultrasonic peening treatment(UPT) on welded joints of a new material. The material is a new generation of fine grain and high purity SS400 steel that has the same ingredients as the traditional low carbon steel. The specimens are in two different states:welded and ultrasonic peening conditions. The corresponding fatigue testing data were analyzed according to the regulation of the statistical method for fatigue life of the welded joints established by International Institute of Welding(IIW). Welding residual stress was considered in two different ways: the constant stress ratio R = 0.5 and the Ohta method. The nominalstress-number (σ-N) curves were corrected because of the different plate thickness compared to the standard and because there was no mismatch or angular deformation. The results indicated that: 1 ) Compared with the welded specimens, when the stress range was 200 MPa, the fatigue life of the SS400 steel specimens treated by ultrasonic peening is prolonged by over 58 times, and the fatigue strength FAT corresponding to 106 cycles is increased by about 66％; 2) As for the SS400 butt joint ( single side welding double sides molding) , after being treated by UPT, the nominal S-N curve (m = 10) of FAT 100 MPa(R =0.5) should be used for fatigue design. The standard S-N curves of FAT 100 MPa (R = 0.5, m = 10) could be used for fatigue design of the SS400 steel butt joints treated by ultrasonic peening. 相似文献
17.
Influences of Randomly Distributed Wall THickness of Beverage Can on Its Strength and Stiffness 总被引：1，自引：0，他引：1
This paper describes the research undertaken on the strength and stiffness of fluctuation on the wall thickness of steel beverage cans using the Monte-Carlo stochastic finite element method.Sample distributions were firestly assumed and then proven using the data observations of the wall thickness.the APDL language was then applied,and the stresses and displacements of the can were calculated by using the ANSYS software.It is concluded that the structureal reliability of a steel-making beverage can be estimated accurately. 相似文献
18.
ZHU Yuan-sheng 《重庆大学学报(英文版)》2007,6(1):50-54
Geotextile tube technology has been increasingly used in dykes. In this work reinforcement theory and circle method were employed to examine the allowable tensile limit of the geotextile tube and the stability factor of the slip surface of the dyke. The formulas to calculate the layer-to-layer spacing and size of geotextile tubes applied to double prism dykes were deduced. The application of these formulas was illustrated by several examples. The calculation results indicate that unequal spacing arrangement is more economical than equal spacing and the layer number of required geotextile tubes decreases with the increase of allowable tensile strength of the geotextile. 相似文献
19.
INTRODUCTION Creep is an internal characteristic of concrete under long-term load. A long time has elapsed since the first discovery of concrete creep in 1907 by Hatt. Many researches have been devoted to this complex problem ever since. However, despite major suc-cesses, the creep phenomenon is still far from being fully understood, even though the phenomenon has occupied some of the best minds in the field, such as Glanville, Dischinger, Troxell, Pickett, Neville, etc. Creep phenome… 相似文献