{"id":29345,"date":"2026-06-08T07:36:48","date_gmt":"2026-06-08T07:36:48","guid":{"rendered":"https:\/\/support.buildsoft.eu\/?post_type=ht_kb&#038;p=29345"},"modified":"2026-06-15T10:13:38","modified_gmt":"2026-06-15T10:13:38","slug":"is-it-possible-to-ask-the-optimal-h_opt-and-minimal-beam-height-h_min-in-diamonds","status":"publish","type":"ht_kb","link":"https:\/\/support.buildsoft.eu\/nl\/knowledge-base\/is-it-possible-to-ask-the-optimal-h_opt-and-minimal-beam-height-h_min-in-diamonds\/","title":{"rendered":"Is it possible to ask the optimal h_opt and minimal beam height h_min in Diamonds?"},"content":{"rendered":"\n<p>Unfortunately that&#8217;s not possible at the moment, but you can calculate it using the tool below (EN 1992-1-1:2002). <\/p>\n\n\n\n<!DOCTYPE html>\n<html lang=\"en\">\n<head>\n  <meta charset=\"UTF-8\" \/>\n  <meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\"\/>\n  <link href=\"https:\/\/fonts.googleapis.com\/css2?family=Bitter:wght@400;600;700&#038;family=Lato:wght@300;400;700&#038;display=swap\" rel=\"stylesheet\"\/>\n  <script src=\"https:\/\/cdnjs.cloudflare.com\/ajax\/libs\/jquery\/3.7.1\/jquery.min.js\"><\/script>\n  <!-- MathJax for LaTeX rendering -->\n  <script>\n    window.MathJax = {\n      tex: { inlineMath: [['\\\\(','\\\\)']], displayMath: [['\\\\[','\\\\]']] },\n      options: { skipHtmlTags: ['script','noscript','style','textarea','pre'] }\n    };\n  <\/script>\n  <script src=\"https:\/\/cdnjs.cloudflare.com\/ajax\/libs\/mathjax\/3.2.2\/es5\/tex-chtml.min.js\"><\/script>\n  <style>\n    *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }\n\n    :root {\n      --red: #e74c3c;\n      --red-light: #fdf2f1;\n      --red-mid: #f9d6d3;\n      --dark: #1a1a2e;\n      --mid: #4a4a6a;\n      --light: #7a7a9a;\n      --border: #e0e0ee;\n      --bg: #ffffff;\n      --card: #f8f8fc;\n    }\n\n    body {\n      font-family: 'Lato', sans-serif;\n      background: var(--bg);\n      color: var(--dark);\n      min-height: 100vh;\n      padding: 40px 20px 80px;\n    }\n\n    .container {\n      max-width: 720px;\n      margin: 0 auto;\n    }\n\n    .topbar {\n      display: flex;\n      align-items: center;\n      gap: 8px;\n      font-size: 13px;\n      color: var(--light);\n      margin-bottom: 32px;\n    }\n    .topbar span { color: var(--red); font-weight: 700; }\n    .topbar .sep { color: var(--border); }\n\n    .section-heading {\n      font-family: 'Bitter', serif;\n      font-size: 13px;\n      font-weight: 700;\n      letter-spacing: 0.12em;\n      text-transform: uppercase;\n      color: var(--red);\n      margin-bottom: 18px;\n      padding-bottom: 8px;\n      border-bottom: 2px solid var(--red-mid);\n    }\n\n    .card {\n      background: var(--bg);\n      border: 1px solid var(--border);\n      border-radius: 10px;\n      padding: 28px 32px;\n      margin-bottom: 20px;\n      box-shadow: 0 2px 12px rgba(0,0,0,0.04);\n    }\n\n    .field-grid {\n      display: grid;\n      grid-template-columns: 1fr 1fr;\n      gap: 18px 24px;\n    }\n    @media (max-width: 540px) {\n      .field-grid { grid-template-columns: 1fr; }\n      .card { padding: 20px 18px; }\n    }\n\n    .field { display: flex; flex-direction: column; gap: 6px; }\n\n    label {\n      font-size: 13px;\n      font-weight: 700;\n      color: var(--mid);\n      letter-spacing: 0.02em;\n    }\n    label sub { font-size: 10px; font-style: italic; }\n\n    .input-wrap {\n      display: flex;\n      align-items: stretch;\n      border: 1.5px solid var(--border);\n      border-radius: 6px;\n      overflow: hidden;\n      transition: border-color 0.2s;\n      background: #fff;\n    }\n    .input-wrap:focus-within {\n      border-color: var(--red);\n      box-shadow: 0 0 0 3px rgba(231,76,60,0.08);\n    }\n    .input-wrap input {\n      flex: 1; border: none; outline: none;\n      padding: 10px 12px; font-size: 15px;\n      font-family: 'Lato', sans-serif;\n      color: var(--dark); background: transparent; min-width: 0;\n    }\n    .input-wrap input::placeholder { color: #c0c0d8; }\n    .unit-badge {\n      display: flex; align-items: center; padding: 0 12px;\n      background: var(--card); border-left: 1.5px solid var(--border);\n      font-size: 12px; font-weight: 700; color: var(--light);\n      white-space: nowrap; letter-spacing: 0.04em;\n    }\n\n    .hint { font-size: 11.5px; color: var(--light); margin-top: 1px; }\n\n    \/* National Annex *\/\n    .annex-group { display: flex; gap: 12px; }\n    .annex-option { flex: 1; position: relative; }\n    .annex-option input[type=\"radio\"] { position: absolute; opacity: 0; width: 0; height: 0; }\n    .annex-option label {\n      display: flex; align-items: center; justify-content: center;\n      gap: 8px; padding: 10px 14px;\n      border: 1.5px solid var(--border); border-radius: 6px;\n      cursor: pointer; font-size: 14px; font-weight: 700;\n      color: var(--mid); transition: all 0.2s; background: #fff; text-align: center;\n    }\n    .annex-option input[type=\"radio\"]:checked + label {\n      border-color: var(--red); background: var(--red-light);\n      color: var(--red); box-shadow: 0 0 0 3px rgba(231,76,60,0.08);\n    }\n    .annex-option label:hover { border-color: #c0c0d8; background: var(--card); }\n    .annex-alpha { font-size: 11px; font-weight: 400; opacity: 0.7; }\n\n    \/* \u2500\u2500 Results card \u2013 always visible, white bg \u2500\u2500 *\/\n    .results-card {\n      background: #ffffff;\n      border: 1px solid var(--border);\n      border-radius: 10px;\n      padding: 28px 32px;\n      margin-bottom: 20px;\n      box-shadow: 0 2px 12px rgba(0,0,0,0.04);\n    }\n\n    .results-heading {\n      font-family: 'Bitter', serif;\n      font-size: 13px;\n      font-weight: 700;\n      letter-spacing: 0.12em;\n      text-transform: uppercase;\n      color: var(--red);\n      margin-bottom: 18px;\n      padding-bottom: 8px;\n      border-bottom: 2px solid var(--red-mid);\n    }\n\n    .results-grid {\n      display: grid;\n      grid-template-columns: 1fr 1fr;\n      gap: 16px;\n      margin-bottom: 24px;\n    }\n    @media (max-width: 600px) { .results-grid { grid-template-columns: 1fr; } }\n\n    .result-block {\n      background: var(--card);\n      border-radius: 8px;\n      padding: 20px 24px 24px;\n      border: 1px solid var(--border);\n    }\n    .result-block.highlight {\n      background: var(--red-light);\n      border-color: var(--red-mid);\n    }\n\n    .result-label {\n      font-size: 12px; font-weight: 700;\n      letter-spacing: 0.06em; text-transform: uppercase;\n      color: var(--light); margin-bottom: 8px;\n    }\n    .result-value {\n      font-family: 'Bitter', serif;\n      font-size: 30px; font-weight: 700;\n      color: var(--dark); line-height: 1;\n    }\n    .result-value.red { color: var(--red); }\n    .result-unit {\n      font-family: 'Lato', sans-serif;\n      font-size: 14px; font-weight: 400;\n      color: var(--light); margin-left: 4px;\n    }\n    .result-placeholder {\n      font-family: 'Bitter', serif;\n      font-size: 22px; font-weight: 400;\n      color: #c0c0d8; line-height: 1;\n    }\n\n    \/* Formula rendered below each result value *\/\n    .result-formula {\n      margin-top: 12px;\n      padding-top: 10px;\n      border-top: 1px solid rgba(0,0,0,0.07);\n      font-size: 13px;\n      color: var(--mid);\n    }\n    .result-block.highlight .result-formula {\n      border-top-color: var(--red-mid);\n    }\n\n    \/* Param chips *\/\n    .params-row {\n      display: flex; flex-wrap: wrap; gap: 8px;\n      margin-top: 16px; padding-top: 16px;\n      border-top: 1px solid var(--border);\n    }\n    .param-chip {\n      background: var(--card);\n      border: 1px solid var(--border);\n      border-radius: 4px; padding: 4px 10px;\n      font-size: 11.5px; color: var(--light);\n    }\n    .param-chip span { color: var(--dark); font-weight: 700; }\n\n    .pending-msg {\n      text-align: center;\n      padding: 20px 0 8px;\n      font-size: 14px;\n      color: #c0c0d8;\n      font-style: italic;\n    }\n  <\/style>\n<\/head>\n<body>\n<div class=\"container\">\n\n  <!-- Material & Section -->\n  <div class=\"card\">\n    <div class=\"section-heading\">Material &amp; Section Properties<\/div>\n    <div class=\"field-grid\">\n      <div class=\"field\">\n        <label>Characteristic concrete strength f<sub>ck<\/sub><\/label>\n        <div class=\"input-wrap\">\n          <input type=\"number\" id=\"fck\" placeholder=\"e.g. 25\" min=\"0\" step=\"any\"\/>\n          <span class=\"unit-badge\">N\/mm\u00b2<\/span>\n        <\/div>\n      <\/div>\n      <div class=\"field\">\n        <label>Partial safety factor \u03b3<sub>c<\/sub><\/label>\n        <div class=\"input-wrap\">\n          <input type=\"number\" id=\"gamma_c\" placeholder=\"1.5\" value=\"1.5\" min=\"0\" step=\"any\"\/>\n          <span class=\"unit-badge\">\u2014<\/span>\n        <\/div>\n        <span class=\"hint\">Default value: 1.5<\/span>\n      <\/div>\n      <div class=\"field\">\n        <label>Beam width b<\/label>\n        <div class=\"input-wrap\">\n          <input type=\"number\" id=\"b\" placeholder=\"e.g. 300\" min=\"0\" step=\"any\"\/>\n          <span class=\"unit-badge\">mm<\/span>\n        <\/div>\n      <\/div>\n      <div class=\"field\">\n        <label>Gross concrete cover c<\/label>\n        <div class=\"input-wrap\">\n          <input type=\"number\" id=\"c\" placeholder=\"e.g. 40\" min=\"0\" step=\"any\"\/>\n          <span class=\"unit-badge\">mm<\/span>\n        <\/div>\n      <\/div>\n    <\/div>\n  <\/div>\n\n  <!-- Loading & Annex -->\n  <div class=\"card\">\n    <div class=\"section-heading\">Loading &amp; National Annex<\/div>\n    <div class=\"field-grid\">\n      <div class=\"field\">\n        <label>Applied ULS bending moment M<sub>Ed,ULS<\/sub><\/label>\n        <div class=\"input-wrap\">\n          <input type=\"number\" id=\"M_Ed\" placeholder=\"e.g. 120\" min=\"0\" step=\"any\"\/>\n          <span class=\"unit-badge\">kNm<\/span>\n        <\/div>\n      <\/div>\n      <div class=\"field\">\n        <label>National Annex (\u03b1<sub>cc<\/sub>)<\/label>\n        <div class=\"annex-group\">\n          <div class=\"annex-option\">\n            <input type=\"radio\" name=\"annex\" id=\"annex_none\" value=\"1.0\" checked\/>\n            <label for=\"annex_none\">[&#8211;] <span class=\"annex-alpha\">\u03b1<sub>cc<\/sub> = 1.00<\/span><\/label>\n          <\/div>\n          <div class=\"annex-option\">\n            <input type=\"radio\" name=\"annex\" id=\"annex_be\" value=\"0.85\"\/>\n            <label for=\"annex_be\">BE <span class=\"annex-alpha\">\u03b1<sub>cc<\/sub> = 0.85<\/span><\/label>\n          <\/div>\n        <\/div>\n      <\/div>\n    <\/div>\n  <\/div>\n\n  <!-- Results \u2013 always visible -->\n  <div class=\"results-card\" id=\"results\">\n    <div class=\"results-heading\">Calculated Results<\/div>\n\n    <!-- Placeholder shown before inputs are complete -->\n    <div id=\"pending-msg\" class=\"pending-msg\">Fill in all input fields above to see the results.<\/div>\n\n    <!-- Result blocks \u2013 always shown; values hidden until calculated -->\n    <div class=\"results-grid\">\n      <div class=\"result-block highlight\">\n        <div class=\"result-label\">Optimal effective depth d<sub>opt<\/sub><\/div>\n        <div class=\"result-value red\" id=\"res_dopt\" style=\"display:none;\">\u2014<span class=\"result-unit\">mm<\/span><\/div>\n        <div class=\"result-formula\">\n          \\( d_\\text{opt} = 2.51 \\cdot \\sqrt{\\dfrac{M_{Ed,ULS}}{b \\cdot \\alpha_{cc} \\cdot \\dfrac{f_{ck}}{\\gamma_c}}} \\)\n        <\/div>\n      <\/div>\n      <div class=\"result-block\">\n        <div class=\"result-label\">Optimal total height h<sub>opt<\/sub><\/div>\n        <div class=\"result-value\" id=\"res_hopt\" style=\"display:none;\">\u2014<span class=\"result-unit\">mm<\/span><\/div>\n        <div class=\"result-formula\">\n          \\( h_\\text{opt} = d_\\text{opt} + c \\)\n        <\/div>\n      <\/div>\n      <div class=\"result-block\">\n        <div class=\"result-label\">Minimum effective depth d<sub>min<\/sub><\/div>\n        <div class=\"result-value\" id=\"res_dmin\" style=\"display:none;\">\u2014<span class=\"result-unit\">mm<\/span><\/div>\n        <div class=\"result-formula\">\n          \\( d_\\text{min} = 1.78 \\cdot \\sqrt{\\dfrac{M_{Ed,ULS}}{b \\cdot \\alpha_{cc} \\cdot \\dfrac{f_{ck}}{\\gamma_c}}} \\)\n        <\/div>\n      <\/div>\n      <div class=\"result-block\">\n        <div class=\"result-label\">Minimum total height h<sub>min<\/sub><\/div>\n        <div class=\"result-value\" id=\"res_hmin\" style=\"display:none;\">\u2014<span class=\"result-unit\">mm<\/span><\/div>\n        <div class=\"result-formula\">\n          \\( h_\\text{min} = d_\\text{min} + c \\)\n        <\/div>\n      <\/div>\n    <\/div>\n\n    <div class=\"params-row\" id=\"params_row\" style=\"display:none;\"><\/div>\n  <\/div>\n\n<\/div>\n\n<script>\n$(function () {\n\n  function getVal(id) { return parseFloat($('#' + id).val()); }\n  function fmt(v) { return isFinite(v) ? Math.ceil(v).toString() : '\u2014'; }\n\n  function calculate() {\n    var fck     = getVal('fck');\n    var gamma_c = getVal('gamma_c');\n    var b       = getVal('b');\n    var c       = getVal('c');\n    var M_kNm   = getVal('M_Ed');\n    var alpha   = parseFloat($('input[name=\"annex\"]:checked').val());\n\n    if (![fck, gamma_c, b, c, M_kNm].every(function(v){ return isFinite(v) && v > 0; })) {\n      $('.result-value').hide();\n      $('#params_row').hide();\n      $('#pending-msg').show();\n      return;\n    }\n\n    \/\/ Convert M: kNm \u2192 N\u00b7mm\n    var M_Nmm = M_kNm * 1e6;\n    \/\/ denom: b[mm] \u00b7 alpha \u00b7 (fck\/gamma_c)[N\/mm\u00b2] \u2192 [N\/mm]\n    \/\/ ratio: M_Nmm[N\u00b7mm] \/ denom[N\/mm] \u2192 [mm\u00b2]  \u2192 sqrt \u2192 [mm] \u2713\n    var denom = b * alpha * (fck \/ gamma_c);\n    var ratio = M_Nmm \/ denom;\n\n    var d_opt = 2.51 * Math.sqrt(ratio);\n    var d_min = 1.78 * Math.sqrt(ratio);\n    var h_opt = d_opt + c;\n    var h_min = d_min + c;\n\n    $('#res_dopt').html(fmt(d_opt) + '<span class=\"result-unit\">mm<\/span>');\n    $('#res_hopt').html(fmt(h_opt) + '<span class=\"result-unit\">mm<\/span>');\n    $('#res_dmin').html(fmt(d_min) + '<span class=\"result-unit\">mm<\/span>');\n    $('#res_hmin').html(fmt(h_min) + '<span class=\"result-unit\">mm<\/span>');\n\n    var annexLabel = alpha === 0.85 ? 'BE' : '[--]';\n    $('#params_row').html(\n      '<div class=\"param-chip\">f<sub>ck<\/sub> = <span>' + fck + ' N\/mm\u00b2<\/span><\/div>' +\n      '<div class=\"param-chip\">\u03b3<sub>c<\/sub> = <span>' + gamma_c + '<\/span><\/div>' +\n      '<div class=\"param-chip\">b = <span>' + b + ' mm<\/span><\/div>' +\n      '<div class=\"param-chip\">c = <span>' + c + ' mm<\/span><\/div>' +\n      '<div class=\"param-chip\">M<sub>Ed<\/sub> = <span>' + M_kNm + ' kNm<\/span><\/div>' +\n      '<div class=\"param-chip\">\u03b1<sub>cc<\/sub> = <span>' + alpha + ' (' + annexLabel + ')<\/span><\/div>'\n    ).show();\n\n    $('#pending-msg').hide();\n    $('.result-value').show();\n  }\n\n  $('input[type=\"number\"], input[type=\"radio\"]').on('input change', calculate);\n  calculate();\n});\n<\/script>\n<\/body>\n<\/html>\n","protected":false},"excerpt":{"rendered":"<p>Unfortunately that&#8217;s not possible at the moment, but you can calculate it using the tool below (EN 1992-1-1:2002). Material &amp; Section Properties Characteristic concrete strength fck N\/mm\u00b2 Partial safety factor \u03b3c \u2014 Default value: 1.5 Beam width b mm Gross concrete cover c mm Loading &amp; National Annex Applied ULS&#8230;<\/p>\n","protected":false},"author":3,"comment_status":"closed","ping_status":"closed","template":"","format":"standard","meta":[],"ht-kb-category":[68],"ht-kb-tag":[],"_links":{"self":[{"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/ht-kb\/29345"}],"collection":[{"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/ht-kb"}],"about":[{"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/types\/ht_kb"}],"author":[{"embeddable":true,"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/comments?post=29345"}],"version-history":[{"count":3,"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/ht-kb\/29345\/revisions"}],"predecessor-version":[{"id":29830,"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/ht-kb\/29345\/revisions\/29830"}],"wp:attachment":[{"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/media?parent=29345"}],"wp:term":[{"taxonomy":"ht_kb_category","embeddable":true,"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/ht-kb-category?post=29345"},{"taxonomy":"ht_kb_tag","embeddable":true,"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/ht-kb-tag?post=29345"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}