Hello bridge guys,
I'm going to assess a 20 years old post tensioned bridge of which the concrete deck was cast in-situ with travelling gantry attached to cantilever ends.
My question is, after 20 years have gone, is the creep induced by the weight of the gantry still "significant"? I mean is...
In designing transverse prestress in top slab of a box girder, do I have to consider the bending stiffness of the webs which !0 stops the tob slab from "free elastic shortening" and 2) picks up "some prestress load effect" reducing prestressing force in the slab betweem the webs?
Hello,
I am doing the design check of a multi-span steel composite box girder viaduct but struggle to get elastic buckling analysis done.
To check the stability of the bare steel section under self weight of fresh concrete (i.e a steel trough supporting wet conrete), I set up a 3D model formed...
I am going to do a quick analysis for a steel box girder of 20 ft wide top flange, 14-2/3ft bottom flange and 8 ft deep.
The bridge is of 11 spans (each span approx. 165 ft long) and several spans are curved in plan on a radius of 1000 ft. Over each pier, the box is strengthened with a plate...
When I did my FE course at university, I was taught how to do FE formulation (e.g. transforming a PDE into a weak form, defining primary/secondary variables) but not how to apply the results to real engineering problems.
For instance, I know how to solve FE equations to find out say shear...
Is it possoble to do secant bored piled walls on the side slopes of embankment AND a diaphragm wall in the centre of the embankment??
The embankment is 10m wide and 6m high??
I am going to do the preliminary design of a RC arch bridge (pinned at both ends) and would like to know the vert and horiz reactions and bending moment at the apex (Is it equal to zero??) if the arch is subject to a vertical UDL. I don't need an exact value but want to know the "order of...
Three weeks ago, I read a trade newspaper which reported a foundation contractor put some kind of steel sleeve over the top, say 6m, of the bore piles so that the pile would not impose any stress on the top layer of soil. Unfortunately, I can’t remember what it is now.....
Dose anybody know...
I found from some bridge design codes assume the effective length of a column to be 0.85 (say) x physical length if the bottom end is fixed against horiz movement and rotation and the top is restrained from any horiz movement but not the rotation (i.e. a pinned joint). However, I don’t...
When I learnt prestressed beam design at college, the section properties (e.g. I value) of the girder don’t change with time or construction stage on which equations or inequalities for the estimations of prestress force and I value are formed.
However, the current problem is a beam and slab...
The problem I have is pile foundations for a bridge. The bridge has to span over a 12m wide moat and the slopes/banks on both sides are 8m height at 35 degrees. In addition, the site constraint includes that the construction of piles must not stabilize or loosen the soil slope.
Could any...
For the purpose of preliminary design, is there any simple equation which can be used to work out the torsional moment of a curved bridge deck (in plan) if both ends are torsionally restrained.
What I know is that the BM on the bridge is approx equal to w x (arc length)^2 /8.
Another equation...
Can anybody give me some guidance about the design of orthotropic deck design to BS 5400:3?
I have a look at 9.10.2 which deals with the design of stiffened flange and it seems that effect of buckling of the steel plate is not taken into accout...............
I got a compsoite box girder (steel closed box with concrete slab on top) which may cantilever from the pier at about 6m.
Could any body tell me how to minimize the effects of deflection and vibration. Can I install dampers or struts of which the ends are loaded against the tip of the box and...
Classic bending stress for a beam is My/I and the stress at both extremities are not zero. However, for some reasons, I want to make the (equivalent) stress/strain at the soffit is zero so it makes me more easy input them into a bridge analysis program. Can I use parallel axis theorem to...
HILTI produces a chemical grout (e.g. HIT-HY 150) which is able to bond the new steel bars to the existing concrete. However, this product is applicable to concrete structure, does any body there is manufacture has a similar chemical grout for masonry structure?
I’m going to replace a 2 span masonry arch by a steel girder and the span of each arch is about 10m (about 33ft). The existing arches carry two railway tracks which are supported by a layer of 550mm (or 1’9”) thick and 8m (or 26’) wide ballast. Could anybody propose a program for removal and...
I am doing a steel railway bridge which carries 2 heavy rail tracks and spans over 3 tracks at 7.5m below the bottom of the bridge (in the midspan region). For a span / depth ratio of 10, the steel truss might be 8m deep.
Could any bridge guys propose some practical solution of erecting this...
