Stone Matrix Asphalt (SMA) is a gap-graded mix that is gaining popularity worldwide. Various types of fibers are used as additions in SMA asphalt mixture. However, there is not sufficient information available for the selection of different fibers with regard to different applications of SMA pavement. In this paper, SMA-13 using three different fibers: lignin fiber, polyester fiber and basalt mineral fiber, is used as an example. Based on the Marshall test, Schellenberg Binder Drainage test, Cantabro test, Residential stability test, Freezethaw cycle test, Rutting test and Bending test of small beam of the mixtures, the influences of different fibers on road performance of SMA mixture were investigated. The results show that SMA-13 mixtures using mineral fibers exhibit optimal high temperature and low temperature stability; while SMA mixtures using lignin fibers exhibit optimal water stability.

Gravity load redistribution and collapse resistance of structures following loss of load bearing elements due to natural and manmade hazards significantly depend on the floor response. Effects of floor system modeling on collapse resistance of damaged structures are studied in this paper. In particular, axial and flexural constraints imposed by the floor slab on joists and beams of RC structures is evaluated and characterized. The axial constraint imposed by the slab leads to additional compressive force, enhancing flexural response and in turn load carrying capacity of beams and joists. The flexural constraint can be captured by proper modeling approaches and can help improve the response of floor joists and beams. It is shown that the method by which the floor system is modeled has considerable effects on the floor response following loss of load bearing elements. The effects of modeling techniques on the structural response are also evaluated from an energy point of view. The effects of flexural-axial, as well as torsional cracking of the floor slab are evaluated and characterized.

Due to the natural condition of the sudden temperature drop when the cold wave strikes the north part of China in winter, especially XinJiang province, the asphalt pavement structures need to be compared. Based on the pavement structures of the test road sections andthe domestic major pavement structures in other provinces, seven pavement structures were chosen. The numerical simulation of these seven pavement structures was performed and the force situations were analyzed respectively under the condition of extreme climate environment, which is the condition of cooling 40 °C from 0 °C in winter. The analysis of the temperature-load coupling of these pavement structures from seven different base forms were conducted. The comprehensive comparison was also made, such as stresses and strains at the bottom layer of asphalt, the stresses of the base, the shear stresses of the asphalt layer, and the compressive strains of the top of base, etc., in order to choose the preferred and most adapted asphalt pavement structure form.