Abstract:

Calculating foundation deformation by using chord modulus is a China's self-innovation technology. It corrected the faults in compression modulus and various calculation models.,and improved the calculated result. The calculation is based on physical indicators of soil and by software; therefore it is also a simplest method. According to it the goal that to control the deformation in the foundation design specification can be reached. Also, taking region differences and micro-structure differences of soil into consideration, the software can calculate the collapse of different types of loesses considering the factors such as the footing area, foundation pressure, adjacent footing influence and so on, thus assessing the quantitative loess collapsibility. During almost the same time when the chord modulus is being researched; it is also researched in the calculation of metal material deformation in USA, which has replaced method of calculating nonlinear elastic deformation by using the Young’s modulus and was then introduced in China's related specifications.These facts should give us an important inspiration for technology update to use chord modulus in code for design of building foundation. The paper is going to summarize the chord modulus and further clarify this views.

Key words: chord modulus, Young’s modulus, foundation deformation, metal material deformation, technology update