There are a few that are mostly solid at the base of the culm. This chart has a nice description of the typical sizes and characteristics of many species. Notice that the largest diameter species with solid culms described here is the clumping Bambusa stenostachya, which can reach a base diameter of 6 inches and a height of 70 feet. Bambusa burmanica is somewhat more modest, at 4 inches and 50 feet. Another candidate would be Dendrocalamus strictus, which can apparently get to be about 5 inches. The Guaduas from South America are also pretty solid at the base and get to about 4 inches diameter... These are all pretty tropical species, so depending on where you are located they may or may not be easy to find. From memory they all tend to be on the thorny side too If you are in a more temperate or cold climate you might be able to find a running bamboo with solid culms but I'm not aware of any that reach a pretty large diameter.