随着《建筑法》及相关法令、法规的颁布实施，建筑市场已日趋成熟，在保证工程质量的前提下，业主一般都想在有限的投资内追求最为理想的工程实体，满足自身的使用功能。而承包商为了自身的生存，订立合同时往往是保本微利，具体施工时通常利用工程的各种条件，在合同外的部分 With the promulgation and implementation of the “Construction Law” and related laws and regulations, the construction market has matured. Under the precondition of ensuring the quality of the project, the owners generally want to pursue the ideal engineering entity within a limited investment to satisfy their own functions . The contractor for their own survival, the conclusion of the contract is often a small profit and loss, the specific construction of the project usually use a variety of conditions, the contract outside the part