Railway monitoring<\/strong> involves tracking and recording potential ground displacement caused by underground works, to ensure that conditions remain within acceptable limits.<\/p>\n[\/et_pb_blurb][\/et_pb_column][et_pb_column type=”2_5″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_image src=”https:\/\/www.optimum-te.com\/wp-content\/uploads\/2025\/01\/investigations-et-acquisitions-de-donnees.png” title_text=”investigations et acquisitions de donnees” align=”center” _builder_version=”4.27.0″ _module_preset=”default” width=”100%” width_tablet=”100%” width_phone=”100%” width_last_edited=”on|phone” module_alignment=”right” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” global_colors_info=”{}”][\/et_pb_image][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=”4.27.0″ _module_preset=”default” locked=”off” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” header_3_text_color=”#000000″ custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22,%22header_text_color%22,%22header_text_color%22%93}”]<\/p>\n
The importance of data collection for trenchless feasibility studies<\/h3>\n
[\/et_pb_text][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” text_text_color=”#000000″ width=”100%” custom_margin=”||20px||false|false” custom_padding=”||||false|false” locked=”off” global_colors_info=”{}”]<\/p>\n
With the exception of structural monitoring, which takes place during the works construction phase, investigations and data collection should be carried out prior to the detailed trenchless feasibility study (G2 PRO mission). This allows the trenchless engineer to fully understand the project\u2019s environment and propose the most suitable and reliable solution.<\/p>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ module_id=”topographie” _builder_version=”4.27.0″ _module_preset=”default” background_color=”gcid-primary-color” background_enable_image=”off” width=”100%” max_width=”1920px” module_alignment=”center” custom_padding=”50px||50px||false|false” top_divider_style=”curve” top_divider_color=”#FFFFFF” top_divider_height=”30px” top_divider_flip=”vertical” locked=”off” global_colors_info=”{%22gcid-052ae396-db0a-47fc-9945-06590b33bb77%22:%91%22top_divider_color%22%93,%22gcid-primary-color%22:%91%22background_color%22%93}”][et_pb_row _builder_version=”4.27.0″ _module_preset=”default” custom_margin=”||||false|false” custom_padding=”||0px||false|false” animation_style=”fade” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” header_font=”|800||on|||||” header_text_color=”#FFFFFF” header_2_text_color=”#FFFFFF” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_after=” content: %22%22;|| display: inline-block;|| width: 40px;|| height: 7px;|| background-color: #FFC000;||\t\tmargin-bottom:20px” locked=”off” global_colors_info=”{}”]<\/p>\n
Topography<\/h2>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”2_5,3_5″ _builder_version=”4.27.0″ _module_preset=”default” custom_margin=”||||false|false” custom_padding=”0px||0px||false|false” animation_style=”fade” global_colors_info=”{}”][et_pb_column type=”2_5″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_image src=”https:\/\/www.optimum-te.com\/wp-content\/uploads\/2025\/01\/topographie.png” title_text=”topographie” align=”center” _builder_version=”4.27.0″ _module_preset=”default” width=”90%” width_tablet=”100%” width_phone=”100%” width_last_edited=”on|tablet” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” module_alignment_tablet=”center” module_alignment_phone=”center” module_alignment_last_edited=”off|tablet” global_colors_info=”{}”][\/et_pb_image][\/et_pb_column][et_pb_column type=”3_5″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” header_3_text_color=”#FFFFFF” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22,%22header_text_color%22,%22header_text_color%22%93}”]<\/p>\n
Essential data for every trenchless feasibility study<\/h3>\n
[\/et_pb_text][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” text_text_color=”#FFFFFF” width=”100%” custom_margin=”||20px||false|false” custom_padding=”||||false|false” locked=”off” global_colors_info=”{}”]<\/p>\n
To correctly design a trenchless project, it is essential to have an accurate topographical survey along the entire length of the crossing path (low points, high points, changes in elevation, reliefs, etc.).<\/p>\n
Surveys are taken to give the coordinates for each point (X, Y, and Z), using either GPS or drones, based on a predefined reference system specific to each region and\/or country. This generates a representation of the project area, known as the Digital Terrain Model (DTM), which indicates all existing features and level variations: roads, pavements, ditches, trees, buildings, railways, rivers, natural terrain, etc. Based on the DTM, the trenchless engineer can then create the most reliable plans, profiles, and crossing sections possible.<\/p>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=”4.27.0″ _module_preset=”default” custom_margin=”50px||0px||false|false” custom_padding=”0px||0px||false|false” locked=”off” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” text_font=”|700|||||||” text_text_color=”#ffffff” text_font_size=”21px” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22%93}”]<\/p>\n
Topography at a glance<\/p>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”1_2,1_2″ _builder_version=”4.27.0″ _module_preset=”default” background_color=”gcid-e37a376b-a469-4c45-85bd-2260b0f2478d” custom_margin=”10px||||false|false” custom_padding=”20px|30px|20px|30px|true|true” border_radii=”on|10px|10px|10px|10px” locked=”off” global_colors_info=”{%22gcid-e37a376b-a469-4c45-85bd-2260b0f2478d%22:%91%22background_color%22%93}”][et_pb_column type=”1_2″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_blurb use_icon=”on” font_icon=”||fa||900″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|600|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” min_height=”25px” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
In what context ?<\/p>\n
[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”||fa||900″ icon_color=”#FFFFFF” icon_placement=”left” image_icon_width=”6px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”|||0px|false|false” image_icon_custom_padding=”9px|||14px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px|20px|false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22icon_color%22,%22icon_color%22%93}”]<\/p>\n
For all feasibility studies<\/p>\n
[\/et_pb_blurb][\/et_pb_column][et_pb_column type=”1_2″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_blurb use_icon=”on” font_icon=”||fa||900″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|600|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”0px||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Why?<\/p>\n
[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”||fa||900″ icon_color=”#FFFFFF” icon_placement=”left” image_icon_width=”6px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”|||0px|false|false” image_icon_custom_padding=”9px|||14px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px|20px|false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22icon_color%22%93}”]<\/p>\n
To ensure the trenchless project corresponds to the precise site conditions<\/p>\n
[\/et_pb_blurb][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ module_id=”recensement” _builder_version=”4.27.0″ _module_preset=”default” background_color=”#FFFFFF” background_enable_image=”off” width=”100%” max_width=”1920px” module_alignment=”center” custom_padding=”50px||90px||false|false” top_divider_style=”curve” top_divider_color=”gcid-primary-color” top_divider_height=”30px” locked=”off” global_colors_info=”{%22gcid-052ae396-db0a-47fc-9945-06590b33bb77%22:%91%22top_divider_color%22%93,%22gcid-primary-color%22:%91%22background_color%22,%22top_divider_color%22%93}”][et_pb_row _builder_version=”4.27.0″ _module_preset=”default” custom_margin=”||||false|false” custom_padding=”||0px||false|false” animation_style=”fade” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” header_font=”|800||on|||||” header_text_color=”#FFFFFF” header_2_text_color=”gcid-primary-color” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_after=” content: %22%22;|| display: inline-block;|| width: 40px;|| height: 7px;|| background-color: #FFC000;||\t\tmargin-bottom:20px” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22,%22header_2_text_color%22%93}”]<\/p>\n
Network detection<\/h2>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”2_5,3_5″ _builder_version=”4.27.0″ _module_preset=”default” custom_margin=”||||false|false” custom_padding=”0px||0px||false|false” animation_style=”fade” global_colors_info=”{}”][et_pb_column type=”2_5″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_image src=”https:\/\/www.optimum-te.com\/wp-content\/uploads\/2025\/02\/LE-ST-Reseaux-istock.png” title_text=”LE ST – R\u00e9seaux – istock” align=”center” _builder_version=”4.27.0″ _module_preset=”default” width=”90%” width_tablet=”100%” width_phone=”100%” width_last_edited=”on|tablet” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” module_alignment_tablet=”center” module_alignment_phone=”center” module_alignment_last_edited=”off|tablet” global_colors_info=”{}”][\/et_pb_image][\/et_pb_column][et_pb_column type=”3_5″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” text_text_color=”#000000″ width=”100%” custom_margin=”||20px||false|false” custom_padding=”||||false|false” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22,%22header_text_color%22%93}”]<\/p>\n
In addition to topography, the identification of existing underground networks is a critical point for trenchless works, particularly in urban and peri-urban areas.<\/p>\n
Specific regulations establish the legal framework for planning and carrying out construction works near existing underground networks. As such, every OPTIMUM engineer is trained and certified as a designer of underground structures (AIPR certification – Authorization for Works Near Networks)..<\/p>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=”4.27.0″ _module_preset=”default” custom_margin=”20px||0px||false|false” custom_padding=”||0px||false|false” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” header_3_text_color=”#000000″ custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22,%22header_text_color%22,%22header_text_color%22%93}”]<\/p>\n
Existing underground networks: A key challenge for trenchless works<\/h3>\n
[\/et_pb_text][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”gcid-secondary-color” icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#000000″ body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Before the feasibility studies are carried out, all operators with underground networks within a predefined area are notified of potential trenchless works.<\/p>\n
[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”gcid-secondary-color” icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#000000″ body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
The operators are then required, within a few weeks, to confirm the presence or absence of their networks in the area.<\/p>\n
[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”gcid-secondary-color” icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#000000″ body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
If present, the operators must provide georeferenced plans of their networks.<\/p>\n
[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”gcid-secondary-color” icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#000000″ body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Each network is then repositioned on the base maps collected during the topographic survey to ensure that the networks are correctly located.<\/p>\n
[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”gcid-secondary-color” icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#000000″ body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
The networks are classified into three categories, A, B, and C, based on the accuracy and degree of certainty of their location. Underground works can only proceed if all networks are classified as A, meaning they are located with an accuracy of 50cm.<\/p>\n
[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”gcid-secondary-color” icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#000000″ body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
If the networks are classified as B or C, additional on-site investigations must be carried out.<\/p>\n
[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”gcid-secondary-color” icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#000000″ body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
The trenchless engineer can, therefore, be certain during the design phase, of the precise location of the various networks and so ensure that the crossing profile avoids and maintains an dadequate distance from all existing underground networks.<\/p>\n
[\/et_pb_blurb][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=”4.27.0″ _module_preset=”default” custom_margin=”40px||0px||false|false” custom_padding=”0px||0px||false|false” locked=”off” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” text_font=”|700|||||||” text_text_color=”gcid-primary-color” text_font_size=”21px” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22,%22text_text_color%22%93}”]<\/p>\n
Network detection at a glance<\/p>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”1_2,1_2″ _builder_version=”4.27.0″ _module_preset=”default” background_color=”gcid-22313caf-a0bd-4f98-adb7-e9887f0bf068″ custom_margin=”10px||||false|false” custom_padding=”20px|30px|20px|30px|true|true” border_radii=”on|10px|10px|10px|10px” locked=”off” global_colors_info=”{%22gcid-22313caf-a0bd-4f98-adb7-e9887f0bf068%22:%91%22background_color%22%93}”][et_pb_column type=”1_2″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_blurb use_icon=”on” font_icon=”||fa||900″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|600|||||||” body_text_color=”#000000″ body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” min_height=”25px” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
In what context ?<\/p>\n
[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”||fa||900″ icon_color=”gcid-primary-color” icon_placement=”left” image_icon_width=”6px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#000000″ body_font_size=”16px” image_icon_custom_margin=”|||0px|false|false” image_icon_custom_padding=”9px|||14px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px|20px|false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22icon_color%22,%22icon_color%22,%22icon_color%22%93}”]<\/p>\n
Mandatory for all trenchless projects<\/p>\n
[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”||fa||900″ icon_color=”gcid-primary-color” icon_placement=”left” image_icon_width=”6px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#000000″ body_font_size=”16px” image_icon_custom_margin=”|||0px|false|false” image_icon_custom_padding=”9px|||14px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px|20px|false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22%93}”]<\/p>\n
Critical for projects in urban, peri-urban and high density network areas<\/p>\n
[\/et_pb_blurb][\/et_pb_column][et_pb_column type=”1_2″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_blurb use_icon=”on” font_icon=”||fa||900″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|600|||||||” body_text_color=”#000000″ body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Why?<\/p>\n
[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”||fa||900″ icon_color=”gcid-primary-color” icon_placement=”left” image_icon_width=”6px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#000000″ body_font_size=”16px” image_icon_custom_margin=”|||0px|false|false” image_icon_custom_padding=”9px|||14px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px|20px|false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22%93}”]<\/p>\n
To ensure the most reliable trenchless project design<\/p>\n
[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”||fa||900″ icon_color=”gcid-primary-color” icon_placement=”left” image_icon_width=”6px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#000000″ body_font_size=”16px” image_icon_custom_margin=”|||0px|false|false” image_icon_custom_padding=”9px|||14px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px|20px|false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22%93}”]<\/p>\n
To guarantee the integrity of existing networks<\/p>\n
[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”||fa||900″ icon_color=”gcid-primary-color” icon_placement=”left” image_icon_width=”6px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#000000″ body_font_size=”16px” image_icon_custom_margin=”|||0px|false|false” image_icon_custom_padding=”9px|||14px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px|20px|false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22,%22icon_color%22%93}”]<\/p>\n
To ensure smooth running of the trenchless construction phase<\/p>\n
[\/et_pb_blurb][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ module_id=”investigations-geotechniques” _builder_version=”4.27.0″ _module_preset=”default” background_color=”gcid-primary-color” background_enable_image=”off” width=”100%” max_width=”1920px” module_alignment=”center” custom_margin=”||||false|false” custom_padding=”50px||50px||false|false” top_divider_style=”curve” top_divider_color=”#FFFFFF” top_divider_height=”30px” top_divider_flip=”vertical” bottom_divider_color=”gcid-primary-color” bottom_divider_height=”30px” bottom_divider_flip=”vertical” locked=”off” global_colors_info=”{%22gcid-052ae396-db0a-47fc-9945-06590b33bb77%22:%91%22top_divider_color%22%93,%22gcid-primary-color%22:%91%22background_color%22,%22top_divider_color%22,%22background_color%22%93}”][et_pb_row _builder_version=”4.27.0″ _module_preset=”default” background_color=”RGBA(255,255,255,0)” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” animation_style=”fade” border_radii=”off|5px|5px||” locked=”off” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.27.0″ _module_preset=”default” custom_padding=”||0px||false|false” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” header_font=”|800||on|||||” header_text_color=”gcid-primary-color” header_2_text_color=”#FFFFFF” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_after=” content: %22%22;|| display: inline-block;|| width: 40px;|| height: 7px;|| background-color: #FFC000;||\t\tmargin-bottom:20px” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22,%22header_text_color%22%93}”]<\/p>\n
Geotechnical investigations<\/h2>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”3_5,2_5″ _builder_version=”4.27.0″ _module_preset=”default” module_alignment=”center” custom_margin=”0px||||false|false” custom_padding=”0px||0px||false|false” animation_style=”fade” locked=”off” global_colors_info=”{}”][et_pb_column type=”3_5″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” text_text_color=”#FFFFFF” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22%93}”]<\/p>\n
Geotechnical investigations are essential for determining the mechanical characteristics of the ground to be crossed. They are crucial for the detailed feasibility study (G2 PRO mission) and are generally carried out after the preliminary study (G1 ES \/ PGC mission).<\/p>\n
Each trenchless project is unique and requires a tailored programme of geotechnical investigations, based on the site context and the anticipated crossing technique. It is, therefore, essential that the programme is developed by a specialist trenchless engineer, who will pinpoint the exact position of each borehole, as well as the type, depth and tests to be conducted on-site.<\/p>\n
A provisional laboratory testing programme is also prepared by the trenchless engineer ahead of the campaign. It is important though to adjust this programme once the actual site conditions are known, i.e., after the borehole sampling, to avoid unnecessary tests and to ensure that no critical information is overlooked for the subsequent stages of analysis.<\/p>\n
[\/et_pb_text][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” text_font=”|600|||||||” text_text_color=”#FFFFFF” custom_margin=”20px||0px||false|false” custom_padding=”||5px||false|false” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22%93}”]<\/p>\n
Geotechnical investigations are typically a combination of the following:<\/p>\n
[\/et_pb_text][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Core drills<\/strong>, to obtain undisturbed samples<\/p>\n[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Destructive boreholes<\/strong>, to assess soil consistency<\/p>\n[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Excavations<\/strong>, to evaluate the size and quantity of large elements that exceed borehole dimensions<\/p>\n[\/et_pb_blurb][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” text_text_color=”#FFFFFF” custom_margin=”20px||0px||false|false” custom_padding=”||5px||false|false” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22%93}”]<\/p>\n
Some boreholes may also be equipped with piezometers to measure fluctuations in the water table level over time.<\/p>\n
[\/et_pb_text][\/et_pb_column][et_pb_column type=”2_5″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_image src=”https:\/\/www.optimum-te.com\/wp-content\/uploads\/2025\/01\/Investigations-geotechniques.png” title_text=”Investigations g\u00e9otechniques” align=”center” _builder_version=”4.27.0″ _module_preset=”default” width=”90%” module_alignment=”center” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” global_colors_info=”{}”][\/et_pb_image][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=”4.27.0″ _module_preset=”default” custom_margin=”0px||||false|false” custom_padding=”0px||60px||false|false” animation_style=”fade” locked=”off” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” text_text_color=”#FFFFFF” custom_margin=”20px||0px||false|false” custom_padding=”||5px||false|false” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22%93}”]<\/p>\n
When combined with geophysical testing, these geotechnical tests enable a reliable soil model and an interpretive geotechnical profile to be created, both of which are essential to accurately design the trenchless crossing.<\/p>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”2_5,3_5″ _builder_version=”4.27.0″ _module_preset=”default” custom_margin=”0px||||false|false” custom_padding=”0px||60px||false|false” animation_style=”fade” border_radii=”on|10px|10px|10px|10px” locked=”off” global_colors_info=”{}”][et_pb_column type=”2_5″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_image src=”https:\/\/www.optimum-te.com\/wp-content\/uploads\/2025\/01\/investigations-geotechnique.png” title_text=”investigations geotechnique” align=”center” _builder_version=”4.27.0″ _module_preset=”default” width=”80%” module_alignment=”center” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” global_colors_info=”{}”][\/et_pb_image][\/et_pb_column][et_pb_column type=”3_5″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” text_text_color=”#FFFFFF” header_3_text_color=”#FFFFFF” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22,%22header_text_color%22,%22header_text_color%22%93}”]<\/p>\n
Most common in-situ tests<\/h3>\n
[\/et_pb_text][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Soil permeability<\/strong>: This is a key parameter in trenchless work as it helps determine how easily fluid can move through a formation. This is particularly important if a fluid is being used for excavation, e.g., in HDD and Microtunnelling<\/p>\n[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Pressiometric tests<\/strong>: These tests measure the mechanical parameters (limit pressures, creep pressures), which characterise the consistency of the ground at a specific point<\/p>\n[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Penetrometer tests<\/strong> (Cone Penetration Test \/ Standard Penetration Tests): These provide similar information to pressiometric tests. CPT, however, has the advantage of continuously testing the soil. It is also less sensitive to operator precision and can evaluate liquefaction potential<\/p>\n[\/et_pb_blurb][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=”4.27.0″ _module_preset=”default” custom_margin=”0px||||false|false” custom_padding=”0px||60px||false|false” animation_style=”fade” border_radii=”on|10px|10px|10px|10px” locked=”off” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” header_3_text_color=”#FFFFFF” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22,%22header_text_color%22,%22header_text_color%22%93}”]<\/p>\n
Laboratory tests for granular soils (sand or gravel) include<\/h3>\n
[\/et_pb_text][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Grain size or sedimentometry<\/strong>: Measures the size of the soil particles<\/p>\n[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Atterberg limits<\/strong>: Measures the clay content of materials and provides a good indication of their stickiness or swelling potential<\/p>\n[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Methylene blue test<\/strong>: In addition to grain size and sedimentometry, this test helps assess the stickiness or swelling potential of clay<\/p>\n[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Triaxial \/ Shear tests<\/strong>: These measure the intrinsic parameters of a soil, including the angle of friction and cohesion<\/p>\n[\/et_pb_blurb][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”3_5,2_5″ _builder_version=”4.27.0″ _module_preset=”default” custom_margin=”0px||||false|false” custom_padding=”0px||||false|false” animation_style=”fade” border_radii=”on|10px|10px|10px|10px” locked=”off” global_colors_info=”{}”][et_pb_column type=”3_5″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” text_text_color=”#FFFFFF” header_3_text_color=”#FFFFFF” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22,%22header_text_color%22,%22header_text_color%22%93}”]<\/p>\n
Laboratory tests for rocky soils include<\/h3>\n
[\/et_pb_text][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Compressive strength tests<\/strong>, which can be measured directly (UCS) or indirectly (Franklin): It is advisable that both measurements be combines to ensure the true strength of the rock matrix is assessed, rather than the strength of the cementation of an existing fracture plane<\/p>\n[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Tensile strength<\/strong> (Brazilian test), which helps evaluate the rock’s drillability<\/p>\n[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Abrasion and hardness test<\/strong> (Cerchar test)<\/p>\n[\/et_pb_blurb][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” text_text_color=”#FFFFFF” header_3_text_color=”#FFFFFF” custom_margin=”15px||||false|false” global_colors_info=”{}”]<\/p>\n
These rock tests help estimate potential drilling or tunnelling challenges, anticipate the type of tools required, and assess their wear and tear during the construction phase.<\/p>\n
[\/et_pb_text][\/et_pb_column][et_pb_column type=”2_5″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_image src=”https:\/\/www.optimum-te.com\/wp-content\/uploads\/2025\/02\/LE-ST-Inv-geotech-3.png” title_text=”LE ST – Inv g\u00e9otech 3″ align=”center” align_tablet=”center” align_phone=”center” align_last_edited=”on|desktop” _builder_version=”4.27.0″ _module_preset=”default” width=”70%” module_alignment=”right” module_alignment_tablet=”center” module_alignment_phone=”center” module_alignment_last_edited=”on|phone” global_colors_info=”{}”][\/et_pb_image][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ module_id=”investigations-geophysiques” _builder_version=”4.27.0″ _module_preset=”default” background_color=”#FFFFFF” background_enable_image=”off” width=”100%” max_width=”1920px” module_alignment=”center” custom_padding=”70px||70px||false|false” top_divider_style=”curve” top_divider_color=”gcid-primary-color” top_divider_height=”30px” locked=”off” global_colors_info=”{%22gcid-052ae396-db0a-47fc-9945-06590b33bb77%22:%91%22top_divider_color%22%93,%22gcid-primary-color%22:%91%22background_color%22,%22top_divider_color%22%93}”][et_pb_row _builder_version=”4.27.0″ _module_preset=”default” custom_margin=”||||false|false” custom_padding=”||0px||false|false” animation_style=”fade” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” header_font=”|800||on|||||” header_text_color=”#FFFFFF” header_2_text_color=”gcid-primary-color” custom_margin=”||0px||false|false” custom_padding=”0px||0px||false|false” custom_css_after=” content: %22%22;|| display: inline-block;|| width: 40px;|| height: 7px;|| background-color: #FFC000;||\t\tmargin-bottom:20px” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22,%22header_2_text_color%22%93}”]<\/p>\n
Geophysical investigations<\/h2>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”2_5,3_5″ _builder_version=”4.27.0″ _module_preset=”default” custom_margin=”||||false|false” custom_padding=”0px||0px||false|false” animation_style=”fade” global_colors_info=”{}”][et_pb_column type=”2_5″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_image src=”https:\/\/www.optimum-te.com\/wp-content\/uploads\/2025\/01\/OFFRE-Calculs.png” title_text=”OFFRE – Calculs” align=”center” _builder_version=”4.27.0″ _module_preset=”default” width=”90%” width_tablet=”100%” width_phone=”100%” width_last_edited=”on|tablet” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” module_alignment_tablet=”center” module_alignment_phone=”center” module_alignment_last_edited=”off|tablet” global_colors_info=”{}”][\/et_pb_image][\/et_pb_column][et_pb_column type=”3_5″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” header_3_text_color=”#000000″ custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22,%22header_text_color%22,%22header_text_color%22%93}”]<\/p>\n
A valuable addition to geotechnical investigations<\/h3>\n
[\/et_pb_text][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” text_text_color=”#000000″ width=”100%” custom_margin=”||20px||false|false” custom_padding=”||||false|false” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22,%22header_text_color%22,%22header_text_color%22%93}”]<\/p>\n
Geophysical investigations are a valuable addition to geotechnical investigations in complex geotechnical or geological contexts and for large-scale structures.<\/p>\n
These investigations help complement data gathered in a borehole-specific and destructive manner and allow for the geotechnical profile to be precisely refined over the entire crossing length. The results can also help refine or complete the geotechnical investigation programme, particularly by targeting areas where anomalies have been detected.<\/p>\n
The geophysical investigation programme is usually established during the preliminary feasibility study (G1 PGC mission) and then adapted according to the project specifics: site conditions, trenchless crossing depth, the degree of accuracy required.<\/p>\n
Various data acquisition methods exist, such as electrical or seismic techniques, and should be selected based on the specificities of each site as well as the depth of investigation needed for the project.<\/p>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ module_id=”auscultation” _builder_version=”4.27.0″ _module_preset=”default” background_color=”gcid-primary-color” background_enable_image=”off” width=”100%” max_width=”1920px” module_alignment=”center” custom_margin=”||||false|false” custom_padding=”50px||50px||false|false” top_divider_style=”curve” top_divider_color=”#FFFFFF” top_divider_height=”30px” top_divider_flip=”vertical” bottom_divider_color=”gcid-primary-color” bottom_divider_height=”30px” bottom_divider_flip=”vertical” locked=”off” global_colors_info=”{%22gcid-052ae396-db0a-47fc-9945-06590b33bb77%22:%91%22top_divider_color%22%93,%22gcid-primary-color%22:%91%22background_color%22,%22top_divider_color%22,%22background_color%22%93}”][et_pb_row _builder_version=”4.27.0″ _module_preset=”default” background_color=”RGBA(255,255,255,0)” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” animation_style=”fade” border_radii=”off|5px|5px||” locked=”off” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.27.0″ _module_preset=”default” custom_padding=”||0px||false|false” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” header_font=”|800||on|||||” header_text_color=”gcid-primary-color” header_2_text_color=”#FFFFFF” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_after=” content: %22%22;|| display: inline-block;|| width: 40px;|| height: 7px;|| background-color: #FFC000;||\t\tmargin-bottom:20px” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22,%22header_2_text_color%22%93}”]<\/p>\n
Railway monitoring<\/h2>\n
[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”3_5,2_5″ _builder_version=”4.27.0″ _module_preset=”default” module_alignment=”center” custom_margin=”0px||||false|false” custom_padding=”0px||20px||false|false” animation_style=”fade” locked=”off” global_colors_info=”{}”][et_pb_column type=”3_5″ _builder_version=”4.27.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.0″ _module_preset=”default” text_text_color=”#FFFFFF” header_2_text_color=”#FFFFFF” custom_margin=”||0px||false|false” custom_padding=”||20px||false|false” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22header_text_color%22%93}”]<\/p>\n
Trenchless works always result in a modification of ground conditions. The extent of this modification will vary, depending on the trenchless technique being used, the site context, and the depth of the installation. Crossings under existing structures, such as railway lines, require special attention and specific measures to ensure that underground works do not cause any surface disruption.<\/p>\n
[\/et_pb_text][et_pb_blurb use_icon=”on” font_icon=”E||divi||400″ icon_color=”#ffc000″ icon_placement=”left” image_icon_width=”24px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”0px|0px|0px|0px|false|false” image_icon_custom_padding=”0px|0px|0px|0px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px||false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}” locked=”off” global_colors_info=”{%22gcid-secondary-color%22:%91%22icon_color%22%93}”]<\/p>\n
Before and after the works<\/strong>: Verification of the railway platform to ensure that no disruption has occurred that could affect the surrounding environment. Depending on the depth of the trenchless installation, the survey can be carried either<\/p>\n[\/et_pb_blurb][et_pb_blurb use_icon=”on” font_icon=”||fa||900″ icon_color=”gcid-primary-color” icon_placement=”left” image_icon_width=”6px” content_max_width=”100%” _builder_version=”4.27.0″ _module_preset=”default” body_font=”|300|||||||” body_text_color=”#FFFFFF” body_font_size=”16px” image_icon_custom_margin=”|||0px|false|false” image_icon_custom_padding=”9px|||14px|false|false” module_alignment=”left” custom_margin=”||0px||false|false” custom_padding=”||0px|20px|false|false” custom_css_free_form=”.et_pb_blurb_position_left .et_pb_blurb_container {|| padding-left:0px;||}||ul{|| padding:0px!important||}” locked=”off” global_colors_info=”{%22gcid-primary-color%22:%91%22icon_color%22%93}”]<\/p>\n