RC Frame Contractors London are the perfect partners for any construction project. Their experience and expertise ensures the successful completion of your building project. Whether you are looking for a new build or a restoration, they will work with you to create your dream home.
Shear walls
RC Frame Contractors London offer shear walls as a way of strengthening a structure’s lateral resistance against extreme wind and earthquakes. They can be made from steel plates, light-framed plywood, or even braced wood. The goal of shear wall design is to strengthen the building while minimizing fatalities and structural damage. They can be built on-site, or installed into existing structures per the specifications of the structural engineer.
Shear walls can be designed according to the American Concrete Institute Building Code, which specifies design procedures for moderate to low seismic risk. The ACI SP-36 equation can be used to estimate the moment capacity of a rectangular shear wall.
Several research studies have been conducted to understand the behavior of shear walls. Generally, low-rise shear walls have been studied, while high-rise shear walls have not. However, a few studies have investigated high-mid-rise shear walls.
A study by Rasoolinejad and Bazant investigated the structural performance of scaled-down shear walls at 1/10 scale. They tested 11 scaled-down reinforced concrete shear walls to investigate various parameters. They found that the tested specimens showed behavior similar to a large-scale shear wall prototype.
Another study by Sotomura and Mara analyzed the behavior of reinforced concrete shear walls with openings. They also investigated the effects of diagonal reinforcement on the hysteretic response of the walls. They found that the use of diagonal reinforcement improved the hysteretic response of the shear walls.
Similarly, Aktan and Hanson analyzed the cyclic responses of slender reinforced concrete shear walls. They found that a shear wall with a shear-span ratio of approximately 1.5 showed the least predictable behavior. Interestingly, a shear-span ratio of about 2 is dominated by flexure.
One of the earliest studies on modeling reinforced concrete shear walls was done by Yuzugullu in 1972. The study examined the monotonic behavior of a shear wall-frame system. He found that the flexural capacity of a wall was overestimated by about 3%, and he developed an approximate equation to compute the flexural capacity of a shear wall.
It is important to know the maximum shear and moment values, as well as the maximum and minimum ductility classes for a structural wall. These factors can be used to predict the seismic response of RC shear walls.
Calculations and design
Choosing the best RC frame contractors London for your next project can be a daunting task. With all the competition vying for your hard earned cash, it’s important to choose wisely. Here are some things to consider before making your final decision. One thing to remember is that you need to take the client’s requirements into account to ensure you’re getting the best possible results. A lot of work goes into ensuring that the best RC frames are delivered on time and in budget. Having a reputable RC frame supplier in London will allow you to have peace of mind that you’re not getting subpar workmanship.
The best RC frame contractors London has to offer will make sure that your design and construction projects are done right the first time around. Using a reputable company will help you ensure that your project is completed in a timely fashion while preventing the dreaded RC frame fire. A reputable firm will also ensure that your RC projects are well built and the materials are of the highest quality. In fact, you may have already guessed it, but a good RC frame supplier will even do a complete RC re-caulking of your frame if need be.
Curing methods
RC frame contractors in London need to understand the curing methods in order to provide the best quality of reinforced concrete. The right curing method can improve the strength, permeability and durability of the concrete. The proper curing process prevents the evaporation of water and therefore strengthens the material.
A variety of curing methods are used to achieve the desired result. The main objective of curing is to replenish the moisture lost from the surface of the concrete. While using wet curing techniques, the concrete surface is kept wet to ensure adequate hydration. Other methods include sprinkling water on the surface of the concrete, applying plastic sheeting over fresh concrete or submerging the concrete in water.
During curing, the temperature gradient between the concrete core and the surface is maintained at around 20-25 Celsius. This gradient is a key factor in achieving the desired properties of hardened materials. It allows early removal of formwork and also improves strength.
Direct electric curing has been used on a commercial scale for in-situ casting and precast elements. This method is now becoming more popular in the Western world. In Russia, it has been in use since 1933.
Using a special rig, it is possible to perform a fair comparison of the effects of SC and EC. Moreover, it is possible to monitor the evolution of temperature inside the specimen during the curing process.
The electrical data collected during the curing process was automatically logged. Voltage was recorded at 5000 Hz.
The average resistance of the f35 and f70 specimens was smaller during the constant temperature phase than the f00. This is because the amplitude of the voltage waveform was lower. The averaged resistance of the f35 and f70 was also smaller during the rise in temperature phase than the f00.
In order to examine the effect of different curing methods on compressive strength, an extensive experimental campaign was carried out. The specimens were tested in various applications including indirect tension, bending and compression tests. Besides, scanning electron microscopy was conducted with Energy-Disperse X-ray spectroscopy.
The results of these tests were used to assess the residual tensile response. The flexural strength of the specimens with electric curing was eight times smaller than the flexural strength of the steam cured specimens.
Ground movements and subsidence
During construction, one of the main issues is the movement of soil around deep excavations. There are various methods used for predicting ground movements. They can be based on numerical and semi-empirical methods.
In London, the topsoil is dominated by clay. Therefore, the foundations of the buildings are very important to understand. The most common cause of foundation movement is leaking drains. However, there are other factors such as re-grading work, nearby loads, and extreme weather events that can affect the foundations of a building.
A simple present condition survey can help provide information about the types of movement. The results can be useful in determining the extent of movement and the possible reoccurrence. It is also helpful in assessing the possibility of damage to the surrounding structures.
A number of studies have investigated the effect of trench position, building weight and stiffness on the soil-structure interaction. This study has led to a better understanding of the soil-structure interaction problem. The findings include the fact that shrinkable clay soils are different from non-shrinkable soils and therefore have a different behaviour during subsidence.
In Ireland, the most commonly used form of subsidence monitoring is crack width monitors. These consist of two plates fixed at either side of a crack. These readings are taken over a defined period of time and allow the movement to be measured quantitatively. The result is an assessment of the potential reoccurrence of a crack.
There are also fast design tools that can be used to assess the potential damage to the surrounding structures. These tools should also take into account the three-dimensional nature of the problem. These tools will also consider distortions close to a corner.
If the movement is significant, then demolition may be required. The Building Research Establishment (BRE) provides indicative values for tilting of low-rise buildings. They range from the maximum acceptable tilt to the maximum unacceptable tilt.
The Institute of Structural Engineers (ISO) defines subsidence as “an unconnected loading that occurs as a result of a change in conditions.” They are able to identify horizontal tensile strains and angular distortion.
