Where retaining walls are of masonry construction, movement joints must be included. Failure to do so could lead to cracks in the retaining wall that weaken its structural integrity and could eventually lead to its failure.
Important points about retaining walls
Don't forget to include movement joints in the wall and use piers on either side to increase strength at the movement joint position. If you're using two separate brick skins in stretcher bond, you have to provide reinforcement by tying them together.
Concrete expansion joints are particularly important where there have been consecutive concrete pours and are also useful when laying concrete within an area bordered by walls or buildings or if objects such as manhole covers need to be incorporated.
For counterfort walls, expansion joint spacing shall be a maximum of 32 feet on centers. For soldier pile and soldier pile tieback walls with concrete fascia panels, expansion joint spacing should be 24 to 32 feet on centers.
Expansion joints are important for preventing cracks within concrete. Concrete is most susceptible to cracks after being poured, because it shrinks slightly as it dries, and then expands or contracts depending on the ambient temperature. Expansion joints are only required when the concrete meets another structure.
X-FOAM is ideal for use as an expansion, contraction, and/or isolation joint in swimming pool decks, curb and gutter work, floor slabs, pavement patch repair, sidewalks, driveways, plazas, parking decks, highways, and airport runways.
Large Gaps and Expansion Joints (Over 1/4″)
All sections should be measured before the filling process. Materials for large concrete gaps and expansion joints include: Non-Sag Caulk: Thick, easy-to-control caulk ideal for larger areas. It requires smoothing but stays in place and works well with a backer rod.
Some builders uses a thumb rule stating that the retaining wall's thickness should be at least one-tenth of the wall's height as a quick reference for residential applications. For instance, 0.4 feet (4.8 inches) of thickness might be the beginning point if the wall is 4 feet high.
A general rule of thumb is to place a joint every 2 or 3 feet per one inch of the slab's thickness. For example, if the concrete slab is 4 inches thick, you can have a slab 8 to 12 feet long before requiring an expansion joint.
Concrete surfaces that support large trucks, heavy machinery, or steady traffic need concrete rebar reinforcement, and any structural concrete, like walls in buildings, should definitely include rebar.
Movement joints in internal walls are not normally necessary for single dwellings unless the walls are straight and unbroken and over 6m long, in which case the block manufacturer's recommendations should be adopted. This may include the use of bed joint reinforcement in the courses above and below window openings.
Attachment can be made with construction adhesive, nails or staples. Be sure that the top of the Expansion Joint is at the top of the intended concrete pour. Expansion Joint material includes a built-in “tear-off” strip. Place “tear-off” strip facing up if caulking is desired after concrete hardens.
An average value for the coefficient of thermal expansion of concrete is about 10 millionths per degree Celsius (10x10-6/C), although values ranging from 7 to 12 millionths per degree Celsius have been observed.
Expansion (or isolation) joints are recommended to be used to isolate different concrete elements or other structural items that abut one another, such as intersecting pavements, inlets, manholes, light poles or bollards, or sidewalk against curb & gutter.
A retaining wall without a footing may experience settlement, leaning, or failure over time. Footings help distribute the weight of the wall and its load, preventing excessive pressure on the soil and ensuring long-term stability.
Expansion joints in walls at 30 m maximum intervals. (If the walls are panel walls between columns at not more than 9 m centres no joints are necessary.) Control joints over centre of openings may be given at half the spacing of expansion joints.
JOINT SPACING
When spacing out joint cuts, the general rule of thumb is that each joint should be around 2-3 times the thickness of the slab, but in feet.
Having the right amount of expansion joints between concrete slabs is essential, but large openings exposed to the elements can cause many different problems over the lifetime of the concrete. For this reason, it's important to fill or seal your expansion joints.
A.: When it first dries, concrete shrinks and undergoes structural alterations that make some of the shrinkage irreversible. Thus, even if it is later resaturated, the initial drying shrinkage isn't fully recovered.
Where retaining walls are of masonry construction, movement joints must be included. Failure to do so could lead to cracks in the retaining wall that weaken its structural integrity and could eventually lead to its failure.
Any reinforced wall or walls over 4 ft. (1.2 m) in height or with slopes or other surcharges above the wall will need a toe drain. In all cases wall rock is located within the cores of the block and a minimum of 12 in. (300 mm) behind the block.
Poured cement walls are hard to beat when it comes to their strength. They are durable and offer more flexural and compressive strength than block walls. Constructing a solid structure that offers as much water resistance as possible is imperative. No matter how bad the climate gets.
You want to clean cracks, at least one quarter to 1/2″ deep. With cracks that or more than a 1/4 deep. You can fill with silica sand, play sand, or backer rod.
Generally speaking, expansion joints should be no farther apart than 2 to 3 times (in feet) the total width of the concrete (in inches). So for a 4‑inch thick concrete slab, expansion joints should be no more than 8 to 12 feet apart.
First, the gap is cleaned of any debris. Then, if the gap is large enough, a backer rod is added to support the caulk. If the gap is smaller, a backer rod is unnecessary and can be filled only using a polymer caulk.