Survival Uses for Bamboo
There are 1575 species of bamboo worldwide and of those 1575 species, 110 are known to be edible. However, bamboo contains high levels of cyanogenic glycosides or free hydrogen cyanide. Boiling the shoots on the edible plants however, will remove the toxin but the effort put forth to determine which plant is edible versus the gain to you may not be worth the effort and some may not consider bamboo a viable food source in some cases.
You essentially would have to be an expert to determine which species is edible and then boil it enough to remove the toxin. In any survival situation you have to weigh outcome versus effort, for example if you burn 1,000 calories hunting down food that only provides 300 calories then you are probably better off conserving your calories.
Shelter Building
Bamboo is ideal material for a shelter. The bamboo is easily harvested and plentiful. The poles are consistent in weight and size and a shelter can be built quickly. The poles can be lashed together using vines or cordage to make sleeping platforms as well. Bamboo can be used to build permanent structures.
Water
Many species of bamboo contain potable water in their hollow joints. Simply bore a hole in a section and drain the water. The sections between the joints can be used to store and carry water as well. Cut off the top of a section to access the hollow chamber, fill with water then plug the hole with a wooden plug and attach cordage to the joint so it can be carried over your shoulder.
A bamboo section can be filled with water and placed near heat to allow the water inside to pasteurize or even boil in some cases for purification. Green bamboo will hold up under high heat long enough to heat the water. You can also use the sections as cooking pots to brew up a quick tea or cook a meal in.
Split a bamboo pole to create rain gutters to channel water off a shelter or vegetation. Once the shelter is built, split the poles and attach several inches below the roofline for water collection.
Fire
Before using for firewood, split the sections to ensure there are not any chambers full of water. The water can boil inside the chambers and cause the section to explode from the expanding steam. Dried bamboo makes an ideal fire spindle for creating a friction fire because the fibrous material creates an ember quickly.
Tools/Weapons
Slender poles make ideal fishing spears. Split the end in to prongs and sharpen then place small pegs between the prongs to hold apart and lash securely. Use as fishing poles as well. Use heavier poles for animal spears or as a self-defense weapon. The slender poles make ideal hunting arrows and long bows can be made from the bamboo as well.
Lash large poles together to make a raft. Bamboo because of the hollow and typically air-filled chambers makes it extremely buoyant, so it is able to float and hold considerable weight. If you make the raft big, enough you can make a sleeping platform and lash poles in to a teepee to provide shelter on the raft.