The European and American Dadi Technology Group Co., Ltd. and Shanghai Shujiu Information Technology Co., Ltd. form a consortium with advanced 3D ground penetrating radar equipment and rich radar data processing and analysis capabilities and experience. Road subgrade quality assessment and other services, including:● Underground cavity detection report;
Urban roads are the lifeblood of the city. Sudden accidents such as road collapse, especially the collapse of arterial roads, will not only cause traffic jams, but also cause accidents such as car crashes and human deaths, causing huge social impact. The road pavement collapse accidents are mainly caused by the existence of hidden dangers of roadbed diseases. Therefore, how to ensure the safety of roadbeds has become an important issue for road managers. With the development of the city, the underground pipelines and subways under the roads are becoming more and more dense. Deep foundation buildings such as underground parking lots around roads are also becoming denser. This has brought unprecedented hidden dangers to the safety of the roadbed.
GPR is a non-destructive testing technology that can be safely used in urban roads. Loose working conditions, no need to close traffic, strong adaptability, strong anti-interference ability, and high detection accuracy and resolution. The rapid development of 3D ground penetrating radar based on antenna array technology has opened up a new one-dimensional space for ground penetrating radar. At the same time, radar data processing technology, especially hole recognition technology, has also made great progress. Therefore, the ground penetrating radar has achieved a very good effect in detecting the underground cavity of the road, and it has become a solution for the prevention of urban road surface collapse.
Based on a vehicle-mounted high-resolution 3D ground penetrating radar system , combined with cavity recognition and analysis software, a technical platform is established. By periodically and rapidly detecting and evaluating urban road subgrades, it is possible to grasp the distribution and extent of roadbed diseases in time to prevent vicious accidents such as road subsidence. occur.
Our complex owns the GeoScopeTM 3D ground penetrating radar designed by the 3D-Radar company in the United States. Compared with the traditional single-channel or several-channel pulsed ground penetrating radar systems widely used in the market, the characteristics of this radar system are mainly two points: the use of innovative frequency stepping radar technology and antenna array technology. A set of high-resolution 3D underground imaging detection systems. This system has been tested and verified in many places in Europe and the United States. It can display and locate, mark, and mark targets such as underground hollows, collapses, underground pipelines, etc. in real time, without returning to the office for data processing and then returning to the site. Greatly improve detection efficiency.
The GeoScopeTM ground penetrating radar antenna system consists of a pair of air-coupled butterfly monopole antennas. Unlike traditional pulsed ground penetrating radar antennas, this ultra-wideband butterfly monopole antenna has a series of continuous frequencies, and its coverage ranges from 100MHz to 3GHz. In actual work, it can collect from 100MHz to 3GHz without replacing the antenna. The frequency data can meet the requirements of different depth measurements and high resolution.
This detection system is equipped with two antenna arrays, an air-coupled antenna for fast measurement, and a ground-coupled antenna as a supplement to the air-coupled antenna array for high-speed data acquisition. The two antenna arrays can be used together to scan quickly without losing detailed features. Both sets of antenna arrays contain a uniform antenna array size. The antenna arrays are arranged at equal intervals of 7.5cm to ensure lateral measurement resolution. The number of antennas is not less than 20, and a single survey can collect 20 survey lines at the same time, which not only greatly improves the survey efficiency, but also realizes real-time 3D imaging. The advantages of 3D imaging in the detection of underground structural defects are obvious. At the same time, it can accurately analyze the thickness of road structural layers, humidity, areas with high water content, cavity locations and sizes.
3DR-Examiner data processing software
方便使用注释功能：为其后生成的报告，数据的用户信息有助于确认有问题的区域。 ● Easy to use annotation function: For the reports generated later, the user information of the data helps to identify the problem areas.
为大量数据处理而设计：100GB数据量的多文件项目可以轻松处理。 ● Designed for large-scale data processing: Multi-file projects with 100GB data volume can be easily processed.
直观的用户图形界面可以迅速浏览带有地理位置的大面积数据： ● Intuitive user graphical interface can quickly browse large area data with geographic location:
a, users can quickly extract useful information from the data;
b, support for importing maps and pictures with geographic locations;
c, help users locate the processed data;
自动层界面跟踪：采用了先进的空间层跟踪算法，只要鼠标在其中一个通道断面上一点，软件便可以自动跟踪所有通道的分层界面。 ● Automatic layer interface tracking: The advanced spatial layer tracking algorithm is adopted. As long as the mouse is on the cross section of one channel, the software can automatically track the layered interface of all channels.
3DR-Analyzer Disease Identification Software
病害自动识别功能提高分析效率：自动抽出疑似空洞区域，极大提高了雷达图像的病害分析效率和精度。 ● Automatic disease identification function improves analysis efficiency: Automatically extract suspected hollow areas, which greatly improves the efficiency and accuracy of disease analysis of radar images.
道路沥青层厚度自动分析：能自动分析沥青层的介电常数，取代传统取芯标定计算介电常数的方法，精确检测道路沥青面层厚度，真正做到无损检测。 ● Automatic analysis of road asphalt layer thickness: It can automatically analyze the dielectric constant of the asphalt layer, instead of the traditional core calibration method to calculate the dielectric constant, accurately detect the thickness of the road asphalt surface layer, and truly achieve non-destructive testing.
3DR-CMP Subgrade Quality Evaluation Software
基于CMP探测方法：与常规收发一体式天线的探地雷达探测方式不同， CMP探测方法是将收发天线阵列以一定的距离按中心线对称排列的一种探测手段。 ● Based on the CMP detection method: Different from the conventional ground penetrating radar detection method of the integrated transmitting and receiving integrated antenna, the CMP detection method is a detection method in which the receiving and transmitting antenna array is symmetrically arranged along a center line at a certain distance.
路基质量自动分析与评价：基于采集到的探测数据形成探地雷达时间剖面图，在时间剖面图上标出雷达波的同向轴追踪线，计算各层的厚度和对应的介电常数。 ● Automatic analysis and evaluation of roadbed quality: Based on the collected detection data, a time-lapse profile of the ground penetrating radar is formed. The time-axis profile of the radar wave is marked, and the thickness of each layer and the corresponding dielectric constant are calculated. Based on the correlation curve between the dielectric constant of the roadbed material and its compactness and water content, the quality of the roadbed is evaluated.
Detection example one
On November 2, 2013, a road collapse occurred at the exit of a certain road in the outer ring road of a city. The collapsed pavement is about 50 square meters in size, and the deepest is about 3 meters. Highway administration units implemented emergency repairs in a timely manner.
Since the site is located above Metro Line 2, there have also been collapses in the surrounding area. In order to grasp the distribution of the hollow in the lower part, on November 15, we conducted a preliminary inspection on the periphery of the subsidence. It is found that there is still a large area of hollow around the collapse, and it is close to the outer ring road. The site of the collapse accident and the newly discovered hole are located above the rail transit of Line 2 and there is a tendency to extend to the main ring road. To this end, we propose to conduct a comprehensive inspection of the outer ring road and the surrounding ramp areas in the area above Line 2 rail transit.
Detection example two
In November 2013, a large amount of water was found on the pavement at the west side of a road (pile number 93K) in a certain city's outer ring road due to a broken water pipe. The road administration unit commissioned us to test the subgrade of the lower road around the pipeline in order to formulate a reasonable maintenance plan.
According to the test results, in the affected sections, there are high aquifers at 0.8m, 1.5m, and 2.7m below the outer ring roads, which are distributed about 20 meters around the water pipe. The distribution of high aquifers at 0.8m, 1.5m, and 2.7m below the inner ring road is about 8 meters to the left and right of the water pipe.
Relevant maintenance units grouted and reinforced the high water-containing area of the upper part of the water pipe based on our inspection results. We re-examined this area after grouting.
The results of the re-examination showed that the abnormal phenomenon of high water content had disappeared, and a new cavity was found. The area of the top of the cavity was 3.25 square meters, which was located under the reinforced concrete slab. The construction policy re-grouted this cavity, the grouting volume reached 4m³, and the height of this cavity was reversed to about 1.2m.
Detection example three
A longitudinal crack with a length of about 100 meters appeared in the middle of a certain section of a city, and a half-dipping road to the north of the crack appeared a slight dip on the side facing the sidewalk. After a site survey, this section of the road is adjacent to a construction site in the north, and there is a deep foundation pit in the lower part. In order to investigate the causes of cracks and pavement slopes, commissioned by the Municipal Facilities Management Center and the developer of the construction site, we used a 3D ground penetrating radar to perform a non-destructive detection of the road.
a. A total of 5 hollows and 2 looses were found in the lower part of the crack section;
b. 2 suspected holes were found adjacent to the non-motorized lane and the sidewalk on the south side;
c. Hollow and loose are caused by the deep foundation pit construction on the construction site and the shear failure of the soil subgrade.
European and American land, Yantai company, several long company profile
Europe and the United States Dadi Technology Group is mainly engaged in the introduction of the world's most advanced civil engineering testing equipment, while providing customers with professional and high-quality product after-sales service and related testing (inspection) services. The company was founded in 1987 and is headquartered in Hong Kong. It has offices in Guangzhou, Beijing, Shanghai, Nanjing, Chengdu, Xi'an, Wuhan, Shenzhen, Shenyang, Fuzhou and Jinan. At present, the company has many professors and professor-level senior engineers. PhD, Master, and more than 160 employees with professional degrees. With the rapid development of the Chinese economy, with the efforts of all the staff of the group company, the European and American Dadi Technology Group has developed from a single sales company of geotechnical test equipment to a set of instrument sales, installation and commissioning, fault repair, lease, and spare parts supply. As well as personnel training, technical consulting and engineering testing (testing) services in one integrated professional group company. Europe and the United States Dadi Technology Group maintains extensive contacts with many foreign manufacturers, often invites foreign experts to teach in China, and sends company technical personnel to foreign manufacturers for training every year, so that we can provide customers with more professional and quality services for civil engineering Engineering testing provides comprehensive application solutions.
Guangzhou Yantai High-tech Engineering Consulting Co., Ltd. is a subsidiary of European and American Dadi Technology Group, which specializes in civil engineering innovation technology testing (inspection) and consulting services. The company was established in August 2001. It mainly applies the world's advanced and high-quality testing (inspection) instruments and equipment provided by the European and American land, fully utilizes the capabilities of advanced testing methods and methods, and carries out civil engineering testing, geotechnical engineering testing, and technology. Consulting and equipment cooperation and leasing. Yantai company has a group of high-quality technical personnel, including well-known experts in the industry and senior technical staff who have engaged in related work for many years in professional fields. Adhering to the corporate culture of "integrity, professionalism, innovation and sharing" and the corporate philosophy of "creating value for customers", we provide customers with high-tech and high-quality civil engineering testing (inspection) and consulting services.
Shanghai Shujiu Information Technology Co., Ltd. was established in October 2008. Mainly engaged in the research and development of new technologies and products for road and bridge inspection / monitoring and services. The R & D team is mainly composed of doctors, masters and bachelors who have returned to China after studying in Japan, Germany, New Zealand and other countries. They have professional backgrounds in cross-industry such as civil inspection, computer automation, applied mathematics, image processing and software engineering. The company's main products include a three-dimensional radar-based automatic roadbed disease analysis system, a PCA road disease automatic analysis system, and a bridge structure safety real-time assessment and early warning system. The main services provided include roadbed disease detection and data analysis services, pavement disease detection and data analysis services, and real-time assessment services for the safety of small and medium beam bridges. Shanghai Shujiu Information Technology Co., Ltd. has borrowed from Japan's hole detection technology since 2012, and independently developed a 3D-Radar radar-based hole recognition technology based on this. With the support of the road administration unit, it has passed a series of field tests and verifications. Established the recognition model of the hollow / void / looseness of the roadbed and established a practical operation process. In the past two years, commissioned by the highway management unit, nearly 20 projects have been tested.