The Ituango dam is an embankment dam that is currently under construction on the Cauca River in Colombia. The largest hydroelectric power plant in Colombia’s history. Three large diversion tunnels used to divert the water from the river around the construction site during construction collapsed as a result of heavy rainfalls. The nearly completed pump house had to be flooded to accommodate premature water build-up in the reservoir. These tunnels would need to be permanently sealed. “Pre-stoppers” would need to be constructed in place to serve as bulk heads between which would ultimately be excavated and back-filled with concrete to permanently seal the tunnels. Additional to standard anti-washout properties, the grout had to withstand swiftly flowing water and exhibit an extended working time at temperatures above 32 degrees C. A custom grout was developed for this application. In the end, hundreds of grout micropiles were tremied, consuming more than 1,650 tons of grout, to produce...
The ACI 562-16 Repair Code is primarily intended for the Licensed Design Professional for providing the requirements necessary for assessing and designing repairs and rehabilitation of existing concrete structures.
The Avalon Mall parking facility is a four level above grade structure, consisting of three suspended parking levels (approximately 7,750sq.m. each) and one on-grade parking level connected to the existing mall with a new pedestrian bridge. RJC was the structural engineer of record. During construction of the parking structure extensive cracking of the suspended parking garage slabs was noted at two of the 24 pours. RJC undertook a visual assessment of the parking slabs in question to determine the extent of the noted cracking and determined over 750lin.m. of cracks ranging in size from 0.5mm to 6.5mm in width. Following the visual assessment destructive testing of the concrete was undertaken to determine its in-situ properties as well as to understand the full extent of the cracking.
High Traffic Commercial/Light Industrial applications including light manufacturing, warehouse/big-box stores and high traffic retail applications present their own unique challenges in concrete repair. This presentation will review concrete repair options that a focused on those application that may require both fast application/turnaround time and strength/use durability for forklifts and trucks. High Traffic Commercial/Light Industrial applications including light manufacturing, warehouse/big-box stores and high traffic retail applications present their own unique challenges in concrete repair. This presentation will review concrete repair options that a focused on those application that may require both fast application/turnaround time and strength/use durability for forklifts and trucks. While there are many option for quick repair that can be open to use in a matter of hours, it is important to acknowledge he potential limitations of these options over the long term.
This video will illustrate an example of how various sections of ACI 562 are applied in the execution of a complex repair project, the repurposing of a historic train deck into a transportation hub for light rail trains and busses. Methods of evaluation and analysis, as guided by ACI 562, will be presented with a discussion of how these provisions lead to various repair approaches presented to the owner.
The presentation, through case studies, talks about emergency response services for structural issues encountered during construction of new design projects. Among other examples is an eleven story precast parking structure. The contractor observed significant diagonal faulted cracking of L-beams (supporting double-tee sections) near bearing locations, few days after pouring topping slab. In addition, inverted-tee girders were observed to be supported on cracked corbels at other locations. A quick turn around was required to mitigate any immediate life safety hazard posed by the structural distresses and buy time for thorough investigation, non-destructive testing, analyses, and repair design. Another example is a seven story precast parking structure. The structure was under construction and reportedly erected out of plumb. Poor concrete placing practices and poor weld detailing led to widespread cracking in multiple structural elements throughout the structure...
This video will discuss how the requirements of ACI 562-16 are used in the evaluation and repair of parking structures. It will take participants through a representative garage project, utilizing Design Example 1 from the Guide to the Use of ACI 562 as the basis. Evaluation and design considerations will be discussed relative to the Repair Code as well as QA/QC and the Engineers' Role during construction.
As long as there is concrete there will be concrete cracks. There is no shortage of repair methods for cracked concrete but the challenge is to find the right one that meets your specific needs. This product demonstration will cover polyurethane injection for leak mitigation. The area of focus will be understanding why concrete cracks, when to use polyurethane or epoxy injection, safety and equipment required for injection work, and lastly, the injection process itself.
Presentation will discuss Vision 2020 (Development, Successes and Challenges) as well as items which still need to be completed. This portion of the presentation will be followed by an overview of the presenter's perspective on the future needs for the concrete repair industry. All attendees will be invited to participate in a workshop to develop a complete list of industry needs (consensus if possible).
Due to improper design or implementation sometimes Part of the New projects are re-executed or repaired. Islamabad - Rawalpindi BRTS (Bus Rapid transit System) Consisted of 20 Stations Covering around 23 km path connecting twin cities. Each station Roof Consisted of ACP Sheets Fixed on Aluminum Frame with Steel supports. The joints of ACP sheets were filled by Silicon but improper materiel and workmanship caused leakage in joints. Total length of joints was over 400,000 RFT. Leakage was invariably from almost every area.