The computation of slope stability is always a very important work for researchers and engineers in this field. The one key issue to solve this problem is the searching of critical slip surface. Generally, the searching of critical slip surface is a very typical complicated continuous optimization problem. To solve this problem very well, firstly, combing the artificial immune system algorithm and evolutionary algorithm with continuous ant colony algorithm, one new bionics algorithm for continuous function optimization which is called immunized continuous ant colony algorithm is proposed, seco...