Experimental Research On High Strength Foamed Concrete And Study On Bond-slip Behavior Of Light Steeland Foamed Concrete

In the construction industry to green,energy conservation direction of the development of the general trend,the self-insulating shear wall system of straw board light steel high strength foam concrete(shear wall)has been developed.The advantages of foamed concrete and light steel keel wall column system have been synthesized,and the system has high bearing capacity and good thermal insulation performance.In order to give full play to the above advantages of shear wall,it was necessary to ensure that light steel and high strength foam concrete work together so that the composite structure could function as a whole.The cooperative work was based on the good bond between light steel and high strength foam concrete.This paper was based on the research of Zhu Songsong,a research group.The high strength foamed concrete(HSC)was developed and applied to the bond-slip test.The bond-slip relationship between C section galvanized cold-formed thin-walled steel and high-strength foamed concrete was deeply explored.The main contents and conclusions of this paper are as follows:The foam concrete developed in this paper,with dry density of 721kg/m~3,had a compressive strength of 5.00MPa and a thermal conductivity of 0.14W/(m·K),which was equivalent to the A10~A12 level specified by JG/T266-2011 foamed concrete,and its thermal conductivity was equivalent to grade A06,which was more obvious than that of ordinary foam concrete.Referring to the traditional bond-slip test method and according to the existing research results of composite shear wall,15 monotonic loading specimens and 9 repeated loading specimens were designed in this paper.The main consideration was the compressive strength of foam concrete and anchorage length of open hole of C section steel(considering the factors of opening hole number and anchoring length),the splicing mode of C section steel section and the number of self-tapping nails(self-tapping on both sides of C section steel)were mainly considered.Total number of nails five factors affecting the number of nails.The main conclusions were as follows:The influence of different influencing factors on the average characteristic bond strength was analyzed,among which,the two structural measures of opening crimping hole and inserting self-tapping nail increase greatly.The monotonous loading mathematical model and the repeated loading skeleton curve model were established,and the critical anchorage length calculation formula was obtained by using the anchorage reliability analysis method.It was proved that the use of C section steel opening edge hole technology and the implantation of self tapping nail could effectively guarantee the yield of C section steel.The joint work of the former C section steel,straw board and foam concrete avoids the fact that the plane section assumption caused by bond slip was not applicable in theory.In this paper,Abaqus finite element software was used to simulate the monotone loading specimen of C section steel,reveal the mechanism of C section steel opening,study the effect of foam concrete as shear joint,and analyze the parameters on the basis of shear stiffness theory.