US artist Richard Serra, whose gigantic steel sculptures made him one of the most important and successful sculptors in the world, has died at the age of 85, his lawyer John Silberman confirmed to dpa on Tuesday evening. According to US media reports, Serra died in the state of New York as a result of pneumonia. Most of Serra’s works, many of them based on models made in Germany, are large and weigh several tons. He has created sculptures for more than 100 public places, from Philadelphia and St Louis in the US to São Paulo in Brazil, and German cities including Bochum and Kassel. However, he …