【正文】 oor of the structure of the three aspects of the problem of the real simulation of underground structures of the structural optimization of a certain significance. Calculation methods and design e to the Conclusion, it can be used as the structural design of underground structures of reference. Most of the use of underground reinforced concrete structures or steel reinforced 10 concrete structure, the current design specifications related to the probability theory are based on limit state design method, the reliability of indicators to measure the reliability of structural ponents using the design of subexpressions coefficient design. Limit state can be divided into the carrying capacity limit state and serviceability limit state, for the carrying capacity limit state should be met: Cracks in the ground floor of building structures to deal with prevention and treatment. Analysis: (1) Design factors: emphasis on the general design of underground construction works vertical wall panels of the reinforced structure and intensity, the level of neglect of horizontal reinforcement cracking strength. Crosssection of the wall structure due to the particle stress is nonuniform shrinkage stress and thermal stress of concrete efforts to achieve the ultimate tensile strength, caused by the plastic deformation and fracture。 another aspects of underground construction is the future direction of space, largespan, the vertical ponent will be an inevitable increase in crosssection. Therefore, the vertical crosssection configuration to optimize materials and even to improve the underground construction of the space is designed to be taken into account. (4) as a result of largescale development of underground space and underground construction and use of the water requirements of more demanding, long, extrawide development of the underground construction joints or less, regardless of the trend is subslit, regardless of current underground construction joints maximum length of over 800m, long and spacious underground construction specification requirements higher than the conventional approach has solved the structure of superlong concrete shrinkage, temperature, deformation and so on, the ground floor of building largescale crack the case more and more. On the other hand, in order to prevent occurrence of cracks to increase the floor, roof and side wall of the reinforcement, so that the sharp increase in the basement of steel, it is therefore necessary to seal a device able to reduce power consumption Ultra contraction of a long side wall and bottom of the internal force and deformation temperature, effectively improve the problem of cracking of underground construction. 9 (5) as a result of underground construction in the fire reached the bottom of the lift requirements for the highlevel and ultrahighrise building, fire pit at the end of the lift is often deeper than 2m, the largest reach 3m. Conventional reinforced concrete pile cap by inch: the requirements of antipunching greater thickness, and then caused by the lift at the end of the partial concave pits and the requirement of the cap to meet the bending, shear, antipunching conditions, go on local concave The site needs to be integrated with the cap around the basically the same thickness, such as the cap, in the partial concave , the caps into a partial thickness of 6m, the amount of concrete and reinforced caused a significant increase, while the base pit at the bottom of the second excavation deeper than 5m, the safety of the Foundation have been affected. Modern underground structure calculation and analysis of three major aspects: 1) the overall structure of underground construction, including both groundlevel structures with basement soil guitar and pure bination of overall analysis of the soil underground construction bined with the overall analysis of colorectal。 sound insulation and sound absorption of the appropriate use of measures to control the noise level allowed. Building to deal with such as a plete portfolio of interior space and changes in the unity of the material texture and contrast the rich interior colors and harmonization, have helped to create a good internal environment, the elimination of the underground environment on people39。 in the rock should be chosen homogeneous lithology, structure simple, thick stone rock hard to avoid the fault fracture zone, seismic zone and instability, such as the 6 slope. In the plain areas, should pay attention to changes in groundwater level and its direct impact on the burial depth of underground construction, construction measures and construction methods。s cold climate, so in large cities, the development of underground mercial center of the city of Montreal has a few underground mercial center even as a construction area of 810,000 square meters, forming an underground city. In addition, industrialized countries also paid attention to the protection of underground construction to play the traditional style of the city to improve the urban environment, urban space, etc. to expand the positive role played by. For example, the city of Nagoya, Japan in conjunction with urban roads alteration, in the ground layout of the mercial street and parking lot, stay out of the ground in addition to the necessary pedestrians, carriageway, in the central part of the park into a largescale city center. Other factors, such as Tokyo, Osaka and other places are also provided with the underground business street. Another example is the University of the United States a number of historical buildings and structures in order to preserve the unity of style and