Effect of Combined Stresses on Fiber- Epoxy Composite Curved Pipe

The aim of this research is to study the behavior of fiber epoxy composite curve pipe under internal pressure and bending moment. The specimens made from woven roving (Mat) fiber glass pipes and epoxy composite with 50% volume fraction are used to manufacturing curved pipe. The experimental work included manufacturing pipe specimens by vacuum bag technique. Pipe specimens were having 100mm inner diameter, 450 mm length of curvature center line of curve pipe with (43 degree) and two wall thickness are 4 and 3 mm. The test rig was designed and performed to study the effect of internal pressure and bending moment on the composite pipes. Also, the tensile test of the samples was done. The analytical expression solution has been accomplished to determine the strain, stress, for hoop and longitudinal direction. It is evident that the hoop stress for woven roving fiber composite pipe was more than longitudinal stress by almost (14%). The maximum internal pressure in the case of internal pressure only was more than compared to the combined internal pressure with bending moment by almost (115%). The most dangerous region is found in the inner arc of the curved pipe (intrude) area.

Research on Risk Management of Gongbei Tunnel Engineering Excavation Team

Gongbei tunnel is the key project of Hong kong-Zhuhai-macao bridge Zhuhai connecting line. The tunnel adopts frozen Curve pipe curtain digging method. In order to ensure the safety of Gongbei tunnel engineering, the rsik management of tunnel excavation team has studied. It has studied on the relevancy between on the organizational structure, rules and regulations, education and training, assessment of rewards and punishments of construction team. Then it make sure the best relevancy risk to plan the risk prevention and controlling measures. Finally, the safety management strategy has targeted to the Excavation team. After practical application, the excavation team of Gongbei tunnel has achieved all-round and focused risk management, which has guided the implementation of the excavation work.

Feasibility Analysis and Status of Shallow Pipe-Jacking Technology in Urban Drainage Systems

Considering the current domestic situation that there is no provision for shallow pipe-jacking (with overburden soil layer not thicker than 3 m and 1.5 times of the pipe external diameter) in the existing water supply and drainage pipeline engineering design and construction specifications, a comprehensive analysis and discussion, based on the actual domestic condition, is made on the feasibility of shallow pipe-jacking technology in urban drainage systems. The problems confronting the shallow pipe-jacking technology theory research are also analyzed and the research status of shallow curve pipe-jacking technology is introduced.