Limited Information Level in Reinforced Concrete Buildings
If the level of knowledge obtained from the buildings for which performance analysis will be made is limited according to TBDY 15.2.4 , the knowledge level coefficient is taken as 0.75. Information level coefficients are used to calculate the capacity of reinforced concrete members in the performance analysis (linear or non-linear) of existing buildings.
15.2.4. Limited Knowledge Level in Reinforced Concrete Buildings
15.2.4.1 - Building Geometry: The structural system plan relay of the building will be obtained with the field study. It is used as an aid in architectural projects, if any, in the work of the building. The information obtained should include the location and material of all reinforced concrete elements and partition walls on each floor, their axial clearances, heights and dimensions, and should be sufficient for the calculation model of the building. The foundation system will be determined by a sufficient number of inspection pits to be opened inside or outside the building. Short columns and similar negativities in the building will be recorded in the floor plan and sections. The relationship of the building with neighboring buildings (detached, adjacent, with / without joints) will be determined.
15.2.4.2 - Element Details:It is assumed that the amount and details of reinforcement in reinforced concrete elements meet the minimum reinforcement conditions at the time the building was built. In order to verify this assumption or to determine the realization rate, the reinforcement will be determined by stripping the concrete cover of 5% of the curtains and columns, at least one on each floor. Concrete cover of one beam from each floor will be stripped in order to determine the reinforcement. Stripping should be done in the middle third of the span of the length of columns and beams. The stripped surfaces will then be covered with high strength repair mortar. In addition, the number and placement of transverse and longitudinal reinforcement in 20% of the walls and columns whose concrete cover is not stripped will be determined by reinforcement detection devices. The reinforcement realization coefficient, which expresses the ratio of the existing reinforcement in the reinforced concrete walls and columns to the minimum reinforcement, will be determined. This coefficient used in determining the wall and column capacities cannot be greater than 1. This coefficient will be applied to all other walls and columns for which reinforcement has not been determined, and the possible reinforcement amounts will be determined. Only reinforcement required under vertical design loads will be used for beams.
15.2.4.3 - Material Properties: From columns or curtains on each floor TS EN 12504-1At least three concrete samples will be taken in accordance with the conditions specified in. The strength values obtained by testing the cores whose length and nominal diameter are equal to each other and 100 mm can be used to determine the current strength of concrete without applying any coefficient. In converting the test results obtained from cores with different length / diameter ratios, appropriate conversion coefficients should be taken as basis. If the total number of samples is three, the lowest compressive strength obtained from the samples will be taken as the current concrete strength without statistical evaluation. If the number of samples is more than three, the greater of the (mean minus standard deviation) value and (0.85 times average) value obtained from the samples will be taken as the current concrete strength. It will be checked whether the smallest value is a statistically deviating result by evaluating the difference between the smallest value and the average of the remaining results among the test results of a group of concrete samples. For this purpose, when evaluating the sample results in the group, if the lowest single value is lower than 75% of the average of the remaining results, this sample is not considered. Reinforcement classAs described in 15.2.4.2 , the stripped surfaces will be determined by visual inspection, the characteristic yield stress of the steel of this class will be taken as the current steel strength. In this examination, the elements with corrosion in the reinforcement will be marked in the plan and this will be taken into account in the element capacity calculations.
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