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Maximum Punching Capacity of Flat SlabesEurocode 2 assesses the maximum punching shear resistance by limiting the nominal shear stress at the periphery of the load to a value equal to the web-crushing limit of beams with shear reinforcement. However, experimental investigations revealed that in most cases the failure occurs at a lower load level once the compression zone at the column face crushes. Furthermore, Eurocode 2 overestimates the maximum shear punching capacity for slabs including stirrups compared to the capacity of slabs including double-headed studs according to construction approvals. To verify the maximum punching shear capacity according to Eurocode 2, at the Institute of Structural Concrete, RWTH Aachen University a punching test on a slab including stirrups as shear reinforcement was conducted and, in addition, tests from literature were evaluated.

Eurocode 2 and the corresponding National Annex were introduced in Germany in 2012. Most of the design provisions for these new standards were adopted from Model Code 1990 and provide a new design approach for ground slabs and footings. For the fib Model Code for Concrete Structures 2010, the punching shear design concept has been revised and introduced in Swiss standard SIA262:2013. This paper presents in detail the design equations for determining the punching capacity according to Eurocode 2, the German National Annex to Eurocode 2, fib Model Code 2010 and SIA 262:2013. Parametric studies have been used to examine the influence of the main parameters (shear span‐depth ratio, effective depth, longitudinal reinforcement ratio and concrete compressive strength) on the punching shear resistance of footings. To quantify the level of safety and the efficiency, the design provisions are compared with systematic test series.

In most countries, for the production and execution of concrete structures with textile reinforcement, building owners must have a general approval (e.g., “abZ” in Germany) or an individual license (e.g., “ZiE” in Germany). Therefore, it is quite common for building authorities to request experimental tests that evaluate the ultimate limit state (ULS) and the serviceability limit state (SLS). However, these experimental tests are detailed, time-consuming and expensive. A practical and simple design model would help to reduce the number of tests needed and would offer structural planners a useful tool. An important aspect is that such design model must fulfil a set of reliability requirements in order to guarantee an adequate safety standard. To this end, probabilistic calculations are required. For the setup of such model, different parameters must be considered, namely the effective depth d and the tensile failure stress of the textile ft for the concrete compressive strength fc. This article presents the probabilistic calculations needed to attain a general safety factor γT that satisfies all the safety requirements for the textile reinforcement of concrete structures with bending load.

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