The Research On CMMR Strengthened RC Axial Loading Member

Composite mortar laminate reinforced with mesh reinforcement (CMMR) is a new kind of material used in the strengthening of R.C. structure. The facture of CMMR includes three processes. First the surface of the strengthened concrete member is made rough, and then steel mesh is spread on the rough concrete surface, last composite mortar is rendered on it.The writer of this thesis made an experimental investigation into axial compressed RC members strengthened with CMMR, which include 9 specimens strengthened with CMMR under one-off load, 4 specimens strengthened with CMMR under secondary load, 2 contrast specimens not strengthened and 1 contrast specimens strengthened with pure composite mortar. The main intention of the experiment is to investigate the rule and the degree in which the stress level index, the section shape, the strength of concrete, the amount and strength of the vertical and horizontal steel mesh bar affect the working performance and ultimate load carrying capacity of the strengthened axial compressed RC member. The most and the least steel mesh amount is also determined in the experiment. In the experiment the strain of concrete, steel bar, steel mesh, composite mortar and the ultimate load carrying capacity are tested. The result indicates that CMMR can increase the working performance and ultimate load carrying capacity of axial compressed RC members greatly.In order to scale the degree in which different factors affect the ultimate load carrying capacity of axial compressed RC members strengthened with CMMR, restrict coefficient λ is defined to scale the restrict degree of horizontal steel mesh bar. Besides finite element software ANSYS is used to analyze the correlation between λ and different factors, then applied calculate method of λ is put forward.At the end an integrated formula is brought forward to calculate the ultimate load of axial compressed RC member strengthened with CMMR. Facture technique is also included.