Field study and investigation of coefficient of friction between precast concrete blocks and rubble mound foundations-----Influence of felt or sludge upon frictional coefficient

In reference to one project case history,based on analyzing causation which made pile foundation displacement,this article used static principle and drilling technology itself to pull up or bury the steel structural drum. The frictional coefficient:μ=25303.14kN/m~2 between steel structural drum and pebble bed is obtained,which might be reference to similar project.

Both the efficiency factors of the reinforcement groups and the similar frictional coefficient should be considered in counting the anti-pull force of the striped reinforcement.

By eliminating air bubbles in the prestressed passage and paste at certain degree of vacuum (>80%), the vacuum grouting technique can make grouting satiable and compact. So it can make equipped corrugated-plastic-tubes airtight, corrosion-resistant , high strength and small frictional coefficient, reducing the frictional loss of prestress and increasing prestress effect about 10 percent.

The conclusion is as follows:there is no remarkable tribological difference between igneous rocks and sedimentary rocks,but the abrasion modes which are attributed to the connatural property of different rock types affect the frictional coefficient of stone.

The squeezing load is shown to be a decreasing function of the Weissenberg number, while the frictional coefficient is only weakly-dependent on the Weissenberg number.

Bounds on flow rate, frictional coefficient, centre of pressure and time-height relation are obtained and compared with classical case, Gross [1].

These characteristics as affected by various rolling conditions (e.g., thickness ratio and shear yield stress ratio of the raw clad sheet, roll speed ratio, reduction, frictional coefficient, roll radius ratio, etc.) were analyzed systematically.

The similar surface conditions after a relative longer shear-sliding distance on polished surfaces lead to the same steady state frictional coefficient, 0.61, for both finishing surfaces.

In comparison with the untreated SiC nanoparticles, the grafted SiC nanoparticles led to more significant reduction in frictional coefficient and wear rate of epoxy.

Coefficient of friction between precast concrete blocks and rubble mound foundations sometimes with the influence of interlaying material, such as various form removal aids used in precasting of concrete blocks and sludge on foundations. The unitedly fixed frictional coefficients,if they are used in designs,could not meet the actual demand in construction work and may result in slipping of concrtet blocks and subsequent destabilization. Field study and investigation of the influence of felt,which...

Coefficient of friction between precast concrete blocks and rubble mound foundations sometimes with the influence of interlaying material, such as various form removal aids used in precasting of concrete blocks and sludge on foundations. The unitedly fixed frictional coefficients,if they are used in designs,could not meet the actual demand in construction work and may result in slipping of concrtet blocks and subsequent destabilization. Field study and investigation of the influence of felt,which was used as form removal aids,and sludge on the foundation upon the frictional coefficient were carried out. The frictional coefficient was reduced to 0. 517 when felt was employed,while frictional coefficient was reduced to 0. 526 when there was sludge with a density of 12. 75kN/cu. m. lying between concrete blocks and foundations. As a result,frictional coefficient was reduced by 15% and 13% respectively,comparing with the frictional coefficient of 0. 607 when there is no influence of inter layers.

The nonlinear finite element method model for frictional contact analysis of tread rubberblock with rigid road surface is established.The deformation and contact stresses generated while the tread block interacting with the road surface were calculated. The effects of the frictional coefficient and the height of the rubber block on the contact stresses were analyzed.

According to construction of extra large and deep water steel cofferdam of Anqin Yangtze River Highway Bridge,besides the prefabricated parts assembled with large crane ship,the construction method of project symmetry was adopted for the anchor system.It was a key and difficult job for the steel cofferdam to touch rocks and lay a foundation.The cofferdam sank down smoothily and controlled the blade to turn over sand through the calculation of average frictional coefficient of cofferdam at 27.5 kPa and...

According to construction of extra large and deep water steel cofferdam of Anqin Yangtze River Highway Bridge,besides the prefabricated parts assembled with large crane ship,the construction method of project symmetry was adopted for the anchor system.It was a key and difficult job for the steel cofferdam to touch rocks and lay a foundation.The cofferdam sank down smoothily and controlled the blade to turn over sand through the calculation of average frictional coefficient of cofferdam at 27.5 kPa and the sinking coefficient more than 1.25.