The Port de Port-au-Prince is the largest seaport in Haiti, and is essential to the country's economy. The Haiti earthquake severely damaged the Port, which disrupted the transport of cargoes into Haiti that were vital to the country's emergency response and post-earthquake recovery. Major contributors to this damage were widespread soil liquefaction, the poor performance of batter piles, and the poor pre-earthquake condition of many components of the Port's waterfront structures. Immediately after the earthquake, a U.S. military task force was deployed to the port to perform emergency repairs needed to reestablish cargo throughput. These repairs restored a significant cargo-throughput capacity at this small but vital seaport within weeks after the earthquake.

The results of several current research programs related to the behavior of dented and corrosion-damaged tubular brace members and their repair is presented. Investigations were conducted involving large-scale testing and analytical studies. The analytical studies invo[ved assessing the ability of several dl~erent methods of analysis, including simple engineering calculations and more sophisticated nonlinear jinite element analysis, to predict damaged and repaired member behavior. The results of the test programs indicated that a significant amount in member deterioration could occur due to either dent or corrosion damage. The extent of the abili~of a repair to reinstate a damaged member to its original design strength was found to depend on the extent of the &mage. The accuracy and reliability of the analytical methods to predict damaged member behavior are illustrated.

This paper presents the results of a study related to predicting the residual strength of dent-damaged steel tubular bracing members in offshore platforms. Damaged specimens experimentally tested in the laboratory were analyzed to predict their ultimate capacity using different analysis methods. These methods include: beam-column formulations; moment-axial load unity check equations; moment-thrust-curvature methods in conjunction with numerical integration; and nonlinear finite element analysis. The reliability and accuracy of these methods was evaluated by comparing the predicted ultimate capacity of 56 dent-damaged specimens with their measured experimental response. This database of test specimens consisted of both small- and large-scale members with dent-damage ranging in depth from 1% to 30% of their diameter, and diameter-to-thickness ratios (Oft) of 26 to 121. The ability of the analytical methods to accurately predict ultimate capacity was found to depend on the extent of dent-damage. The non-linear finite element method was found to provide the most accurate prediction of member capacity. However, the method of choice for routine analysis is the use of unity check equations that have been calibrated for dent-damaged tubular strength prediction. These equations are easy to use and are shown to provide a reasonable estimate of the capacity of damaged members. Introduction At present, there are approximately 3,800 offshore platforms in the U.S. waters, with the majority being in the Gulf of Mexico and the rest scattered along the coast of California and in the Cook Inlet of Alaska1. The average age of these structures is roughly 15 years, with over one-fourth having an age beyond their 20 year designed service life2. As the number of older platforms continues to grow, the oil and gas industry has become increasingly aware of the liability associated with operating an aging offshore infrastructure. Exposure to liability, especially environmental, is becoming an especially large burden for the industry as insurance premiums escalate to balance the risk of platform failure and the subsequent high costs associated with loss of live, environmental devastation, and wasted resources. The financial costs associated with the shut-down, removal, and replacement of these aging platforms with more sophisticated structures are, however, equally prohibitive, and complicated with strict regulatory and environmental requirements. As a result, the oil and gas industry has developed a strong desire to rehabilitate its existing offshore infrastructure, resulting in the need for the development and verification of methods and techniques necessary to assess platform integrity, to strengthen and repair weakened elements, and to extend safe operational life. As part of this maintenance and rehabilitation process, the structural integrity and physical condition of the platform must be thoroughly evaluated before any decisions are made about the safe operation of the structure. This is especially challenging since the assessment of the structural capacity of the platform is complicated by the existence of any deterioration or damage of individual structural elements. Examples of such damage or deterioration typically found in older offshore structures includes global or local corrosion due to environmental exposure, fatigue cracking from continuous wave loading, and dent-damage of structural members due to collision or impact. Despite the ability of the jacket to tolerate a limited number of damaged or missing members, the accumulation of damage reduces the structural integrity of the platform and inherently increases the probability of its failure. Thus, decisions regarding the safety a

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Historically, the seismic design of topsides structures like marine loading arms and cargo transfer hose towers has been done inconsistently and to a wide array of design codes and requirements. The root of this problem has been a forced reference to conventional building codes like the UBC or ASCE 7, which are poorly suited for marine structures and particularly to these kinds of installations. ASCE 61-14 has taken the first steps towards creating appropriate standards for seismic design of topsides structures. However, more needs to be done, and designers have learned valuable lessons about shortcomings that remain in the first edition of the new standard. This paper outlines the problems with existing seismic design codes and makes recommendations for changes to include in ASCE 61-19.