A laser screed is far more than a simple "mechanical trowel." It is an integrated construction platform that combines precision mechanical engineering, laser measurement and control technology, hydraulic transmission, and intelligent control. Its core working principle involves a rotating laser transmitter set up around the job site, which creates an absolutely level (or pre-set sloped) optical reference plane. A laser receiver mounted on the screeding head captures this signal in real-time and relays height information to the machine's control system (the brain). This system then commands the hydraulic servo system (the muscles) to raise or lower the screeding head, maintaining it precisely at the design elevation.
01.Cracking is inherent to the nature of concrete
Occurs with in hours after concrete placement, while it is still in a plastic state. The rate of surface moisture evaporation exceeds the rate of water bleeding from within, causing capillary tension and volumetric shrinkage at the surface. The concrete has very little strength at this stage and cannot resist this shrinkage, leading to irregular, shallow, map-pattern cracks.
Causes: This is the most common cause. After concrete hardens, unhydrated free water within gradually evaporates, causing the cement paste gel to shrink. This shrinkage is restrained by aggregates, reinforcement, or the sub-base, generating tensile stress within the concrete. Cracks appear when this stress exceeds the concrete's capacity. They are typically through-cracks.
02.Prevent and control concrete cracking to create a complete and intact floor.
Optimizing Concrete Mix Proportions:Material Quality ControlRaw Material Selection: Ensure that materials such as cement, crushed stone, and sand meet standards to prevent inadequate concrete strength or poor shrinkage due to material quality issues.Mix Design: Strictly design the mix according to specifications, control the water-cement ratio, and avoid mix deviations that could affect concrete performance.
03.Construction Process Improvement
After pouring, perform secondary vibration (before initial setting) and mechanical tamping (before final setting) in a timely manner to reduce internal voids. 1. Using a laser screed for construction can reduce the number of construction joints, improve flatness to 1.3mm (traditional 4.1mm), and reduce shrinkage stress.
Cover the insulation material (such as plastic sheeting) immediately after final solidification and continue to moisturize and cure for no less than 14 days to avoid cracks caused by sharp temperature differences
When the technical advantages of the laser screed are combined with scientific reinforcement and joint design, optimized low-shrinkage mix designs, and timely, perfect curing practices, we can systematically and maximally control the risk of concrete cracking, ultimately creating a high-quality floor that is not only mirror-flat but also complete and durable.
If you want to know more about Shandong HWAON Machinery Technology Co., Ltd. or have any questions, please feel free to contact us:
• Tel: +8619053785911
• Email: hwaonmachine@gmail.com
• Website: www.hwa-on.com
