The Capacity Properties And Design Method Of Short-bolts Expansive Stressed Grouted Clamp

Clamp using traditional structure with long bolts has the drawbacks ofcomplicated steel structure and cumbersome assembly process. Based on previousresearch of clamps using traditional long bolts structure, this paper introduces ashort-bolts expansive stressed grouted clamp considering the different mechanism ofself-stress formation between traditional stressed grouted clamp and expansivestressed grouted clamp. And the following research works are carried out:Firstly, a research on the capacity properties of short-bolts expansive stressedgrouted clamp is carried out. By model experiments, expansive pressure and slipstress of short-bolts expansive stressed grouted clamp are obtained. Then they arecompared with the data got from previous model experiments for traditional structureclamp of the same size. Judging from the two clamp capacity properties of expansivepressure and slip capacity, the short-bolts clamp has a better performance than theclamp with traditional structure, thus it is more suitable for offshore constructionrepair and structure reinforcement.Secondly, the slip stress of short-bolts expansive stressed grouted clamp is testedunder different slenderness ratios and the relationship between slip stress andslenderness ratios is studied. In the experiment, slenderness ratios were chosen as1.02,1.30,1.67and3.33for the slip stress test. According to the test results, the slip stresschanges are very small and can be considered substantially constant within theslenderness ratio range of1.02~1.67. But, the slip stress reduces obviously when theslenderness ratios increases to3.33. The result has certain guiding significance forconnecting length design of clamps in practical engineering application.Thirdly, the design method of the short-bolts expansive stressed grouted clamp is summarized and determining factors for each basic size are listed. A set of practicaldesign procedure is sorted out for the short-bolts clamp structure. The core principlesof the design method are based on the checks on slip capacity, member crushing andstructural strength, associated with the experiment data and previous designexperience as reference. It established a good foundation for such clamp repairtechnique in practical engineering application.Based on the experimental results of short-bolts clamp, it has a betterperformance than clamp with traditional structure both in expansive pressure and slipstress, and is more suitable for offshore repair and reinforcement. In addition, thestudy of short-bolts clamp design method has laid a solid foundation for theengineering applications of expansive stressed grouted clamp.