The Impact Studies Of Steel Sectional Form On Steel Reinforced Concrete Pier Carrying Capacity

The pier of discharge structure in hydro power project is the key structure to support and ensure the radial gate running safely under the water thrust loads. With the development of hydropower in China, more and more large hydro power station under construction, the corresponding discharge structure Discharge for increasing, working head constantly increasing, the pier suffered loads are increasing. By the limit of Project layout and investment, the size of pier is impossible unrestricted increasing, the conventional reinforced hasn’t meet the requirements on stiffness and load capacity in operating reliable. Therefore, it is necessary to seek a new pier structure to ensure the radial gate operating reliable at high thrust. Based on the characteristics of steel reinforced concrete, the new steel reinforced concrete pier structure proposed with steel reinforced instead of steel sector, and the impact studies carried out in the form of beam cross section influcing on the steel reinforced concrete the pier carrying capacity.In this paper, combined the proposed practical projects, using the finite element method to establish two nonlinear finite element model of ordinary reinforced concrete pier and steel reinforced concrete pier in the same displacement boundary and load conditions. Through comparative analysis of the two pier shows, the tensile stress decreasing trend from a nearby bracket, the inhibitory effect of crack development, and ultimate bearing capacity joint verification of the rationality of the steel reinforced concrete pier.This paper studies the applicability of T-beam, H-beam, channel steel, box beam in the steel reinforced concrete pier, studied the effects of beam cross-section in the form of steel reinforced concrete pier carrying capacity, reached the following conclusions:(1)To both sides of the gate retaining normal operating conditions as a basis for design loads were overloaded load calculated the maximum configuration of T-shaped steel pier ultimate bearing capacity for 4.5 times the normal operation of the design load, H-beam concrete pier, box-shaped steel ultimate bearing capacity of concrete steel reinforced concrete pier and pier slots are less than T-shaped steel pier, compared with T ultimate bearing capacity of steel reinforced concrete pier were reduced by 3.78%,7.33% and 20.44%. From the point of view of ultimate bearing capacity, T-section steel is more suitable for steel reinforced concrete pier.(2) By pier displacement analysis concluded that different sections of the form of the overall deformation of steel reinforced concrete pier close. Bracket bearings and piers downstream appear to downstream relative displacement, and on the side of the pier tail appear larger displacement along the pier height direction. During normal operating conditions, T-beam, H-beam, box-beam, channel steel concrete pier maximum displacement was 0.91mm,0.87mm,0.93mm,0.87mm.(3)From the crack distribution and development of pier to judge, steel in the form of concrete cracking and crack development impact is not obvious, when the load is 0.58 times the normal load, the configuration of the T-shaped steel, H-beam, box beam and channel steel of the pier are in the bracket bearing surface and the pier force intersects corners point first crack. With increasing load, the force bearing bracket body surface and the pier at the intersection of the rear seat bracket to crack development.(4)T-beam, H-beam, channel steel, box beam steel reinforced concrete in vivo Gate Pier monotonic loading process is arranged along the beam direction displacement monotonically increasing (downstream), where the piers and the steel bracket bearing deformation maximum junction. Thickness direction along the pier, piers and corbels bearing steel junction within the largest displacement and deformation.(5)T-beam, H-beam, channel steel, box beam steel reinforced concrete within the first pier of the load at yield were 2.9,2.75,2.83,2.67 times normal operating conditions the design load, ultimate load were 4.5,4.33,3.58,4.17 times the normal design load operating conditions, indicating that the worst ductility trough steel reinforced concrete pier.