This paper is the first of a set of linked publications on the PISA Joint Industry Research Project, which was concerned with the development of improved design methods for monopile foundations in offshore wind applications. PISA involved large-scale pile tests in overconsolidated glacial till at Cowden, north-east England, and in dense, normally consolidated marine sand at Dunkirk, northern France. The paper presents the characterisation of the two sites, which was crucial to the design of the field experiments and advanced numerical modelling of the pile–soil interactions. The studies described, which had to be completed at an early stage of the PISA project, added new laboratory and field campaigns to historic investigations at both sites. They enabled an accurate description of soil behaviour from small strains to ultimate states to be derived, allowing analyses to be undertaken that captured both the serviceability and limit state behaviour of the test monopiles.

中文翻译：

---

PISA桩测试和分析的地面特征

本文是PISA联合工业研究项目的一系列关联出版物中的第一篇，该出版物涉及海上风电应用中单桩基础的改进设计方法的开发。PISA在英格兰东北部的考登（Cowden）进行了超固结的冰层，在法国北部的敦刻尔克（Dunkirk）进行了密集，通常固结的海沙中的大规模桩试验。本文介绍了这两个位置的特征，这对现场实验的设计和桩-土相互作用的高级数值建模至关重要。所描述的研究必须在PISA项目的早期阶段完成，为这两个地点的历史调查增加了新的实验室和野外活动。他们可以准确地描述从小应变到最终状态的土壤行为，