This paper reviews five field assessments of the cathodic protection of coated steel pipelines buried in soils of an average resistivity of 4300 V cm, performed using the close interval survey (CIS) technique and incorporating the instant off potential (IOP) method to measure any voltage drop. Multiple current sources were identified in the surveys, and simultaneous interruption of all the current sources was achieved using synchronised switches. The results presented here highlight the importance of incorporating the IOP method when performing CIS in order to quantify the voltage drop factor and thus improve the interpretation of potential measurements. Unexpected field situations encountered when performing the CIS technique are discussed and the practicality of using corrosion coupons is analysed.

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The cathodic protection (CP) of on-grade coated steel storage tanks deployed on reinforced concrete slabs in soils of 20-30 kΩ cm resistivity was evaluated for two different time periods 9 years apart. The required CP current was calculated and the ohmic drop was measured using the instant-off potential method. The resulting polarisation shift is a useful indicator of the level of protection afforded and whether the potential criterion or the polarisation shift criterion is fulfilled. It was also noted that the greater the ground resistivity, the less corrosive the environment for an on-grade steel structure.

Dissipative zones buildings, in which plastic hinges or plastic strains occur during, for instance, seismic episodes, have been studied for many different types of steel fuse elements. Stainless steel (SS), has attracted attention in this regard due to its high ductility and further studies are needed to determine its performance and usefulness as fuses. The use of SS in the construction industry has represented an advance due to its already known anticorrosive properties in addition to its strength and ductility. However, recent research on cyclic plasticity shows that SS has significant hardening properties, which can be exploited in the use of this material in structural elements to support cyclic loads, such as those occurring during earthquakes. The cyclic plasticity models in SS have been studied with some applications (fatigue, low‐cycle fatigue and extremely low cycle fatigue). Several studies carried out cyclic tests to obtain experimental data, which have been used for numerical models with the utilisation of a combined numerical model of kinematic/isotropic hardening. These studies recommend models to simulate the behaviour of SS under a cyclic load. This work presents an experimental study of the cyclic behaviour of SS when subject to low and extremely low cycle fatigue. Several protocols on tests such as companion, multiple step and arbitrary tests were carried out. The results inferred from the experimental program provide hardening parameters used to study one example of dissipative zones of eccentrically braced frames (EBFs).

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